1. General Principles & Basic Science MCQs

A subpectoral biceps tenodesis requires an additional incision at the insertion of the pectoralis major tendon on the humerus. This can be difficult to do in the lateral decubitus position and certainly this technique does not decrease surgical time when compared to arthroscopic soft-tissue techniques. There have been no level I studies comparing the two techniques; however, the theoretical advantage of the open biceps subpectoral tenodesis is that the biceps tendon is removed from the bicipital groove, which may eliminate a source of pain in the biceps tendon.

Drooping of the left eyelid is a presenting feature of Horner's syndrome. Horner's syndrome represents a disruption of the sympathetic chain via C8 and/or T1 root avulsion after trauma.Brachial plexus injuries are often classified as preganglionic vs. postganglionic injuries. Preganglionic injuries are typically avulsion injuries proximal to the dorsal root ganglion. Clinical features suggestive of lower root avulsion injury include a person falling from height clutching on object to save himself, Horner’s syndrome (drooping of the eyelid (ptosis), pupillary constriction (miosis) and anhidrosis), absence of a Tinel sign or tenderness to percussion in the neck, and a normal histamine test (C8-T1 sympathetic ganglion - intact triple response (redness, wheal, flare)).Caporrino et al. reviewed 102 patients to assess the best modality (e.g. physical examination, MRI and nerve conduction studies [NCSs]) for diagnosing and localizing brachial plexus injuries. They found the best diagnostic performance with physical examination (sensitivity = 97.8%; specificity = 30.8%) and NCSs (sensitivity= 98.9%; specificity = 23.1%). MRI had inferior performance for all measurements. They conclude that NCSs exhibited superior performance to MRI, and should be considered a more reliable supporting tool after detailed physical examination.Incorrect Answers:

TNFα has been implicated in the pathogenesis of many chronic inflammatory diseases. Selective blockade with agents such as etanercept decreases the activation of mesenchymal cells, thereby reducing pannus formation, cartilage destruction, and osteoclastic bone resorption. IL-1 production in response to inflammatory stimulus contributes to the rapid loss of proteoglycans, leading to cartilage destruction and osteoclastic bone resorption. Recombinant forms of IL-1 antagonists such as the drug anakinra effectively block IL-1 by competitively binding to the IL-1 type I receptor. Nonsteroidal anti-inflammatory drugs inhibit the enzymes COX-1 and COX-2, which are necessary for the production of prostaglandins. Abatacept is a selective costimulation modulator that inhibits T lymphocyte activation implicated in pathogenesis of juvenile idiopathic arthritis. Methotrexate is an effective agent in the treatment of rheumatoid arthritis. The mechanism of action of this drug has not been fully elucidated. Proposed actions include decreasing cytokine production through promotion of adenosine release and inhibition of transmethylation reactions that otherwise result in accumulation of toxic compounds (spermine and spermidine).

DISCUSSION: Disk nutrition occurs via diffusion through pores in the end plates. The disk has no direct blood supply, and the anulus is not porous to allow diffusion. The dorsal root ganglion does not provide blood supply to the disc. REFERENCES: Biyani A, Andersson GB: Low back pain: Pathophysiology and management. J Am Acad Orthop Surg 2004;12:106-115. Urban JG, Holm S, Maroudas A, et al: Nutrition of the intervertebral disc: Effect of fluid flow on solute transport. Clin Orthop 1982;170:296-302. Park AE, Boden SD: Intervertebral disk: Form and function, in Einhorn TA, O’Keefe RJ, Buckwalter JA (eds): Orthopaedic Basic Science: Foundations of Clinical Practice, ed 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, in press.

The loss of hair or alopecia, is the only nonreversible effect of anabolic steroid use. Once anabolic steroids are stopped, muscle hypertrophy and training gains are quickly lost and the HDL/LDL ratios return to their preexisting levels. Fortunately, the personality effects and the acute acne are reversible.

Spontaneous osteonecrosis of the medial femoral condyle is seen in the MRI scans, and is most common in women older than age 60 years. Although usually present in the weight-bearing portion of the medial femoral condyle, spontaneous osteonecrosis has also been described involving the lateral femoral condyle and patella. Most patients are seen postcollapse, and the treatment of choice is arthroplasty. Optimal treatment in precollapse stages is controversial.

The type of health insurance in the pediatric population has shown to be a significant factor for access to specialized healthcare in the United States.Access to pediatric orthopaedic management has been well investigated. Numerous Level 4 studies have shown that orthopaedic offices in urban and rural areas prefer treating patients with private insurance over patients with Medicaid.Iobst et al. telephoned 100 urban and rural orthopaedic outpatient offices to schedule an appointment for a 10-year-old patient with a forearm fracture. They showed that 8/100 offices would schedule an appointment within 1 week to the child with Medicaid insurance, as compared to 36/100 that gave an appointment to a child with private insurance.Pierce et al. contacted 42 orthopaedic practices to schedule an appointment for a 14- year-old patient with an ACL injury. They showed that 38/42 offices scheduled an appointment for the child within 2 weeks with private insurance. This compared to 6/42 that scheduled an appointment for a similar child with Medicaid.Incorrect Answers:The perioperative use of which medication has been shown to increase the risk of post-operative infection following orthopaedic procedures in patients with rheumatoid arthritis (RA)?NaproxenLeflunomideSulfasalazineEtanerceptAspirinOf the medications listed, only etanercept has been shown to increase the risk of post- operative infection following orthopaedic procedures in patients with RA.Etanercept is a TNF-alpha antagonist with a short half-life that is administered once or twice weekly in patients with RA. Since TNF-alpha plays a central role in the pathogenesis of RA and is instrumental in causing joint destruction, the inhibition of this molecule has shown excellent results in controlling disease. The most powered study on TNF-alpha inhibitor use in the perioperative period following an orthopaedic procedures demonstrated a significant increase inpost-operative infection.Howe et al. review the medical management of patients with RA who underwent orthopaedic procedures. They state that while there is conflicting information regarding TNF-alpha antagonists, they recommend holding them prior to major orthopaedic interventions.Giles et al. review 91 patients with rheumatoid arthritis who underwent an orthopaedic procedure. They found TNF-alpha inhibitor therapy to be significantly associated with the development of a serious postoperative infection (p=.041)Perhala et al. review 61 patients with RA who were treated with methotrexate during the perioperative period surrounding a total joint arthroplasty. Theyfailed to find a significant increase in complications in this patient group, stating the perioperative use of methotrexate does not affect wound healing or increase the likelihood of periprosthetic infection.Illustration A shows the site of action of TNA-alpha inhibitors in the RA pathway.Incorrect Answers:Communication breakdown is the leading cause of which of the following?Delayed diagnosesMedication errorsSurgical site infections1 and 2All of the aboveCommunication failures are the leading cause of wrong side surgeries, medication errors and diagnostic delays.Poor communication sets up environments in which medical errors can take place. Per the Joint Commission, medical errors may be the among the top 10 causes of death in the United States. Establishing open lines of communication is critical to reduce the risk of error and enhance patient safety.Gandhi et al. designed a framework to study missed or delayed diagnoses and their causes. The most significant factors contributing to errors were poor handoffs, failures in judgment, failures in memory and failures in knowledge.O’Daniel et al. review the importance of professional communication and collaborative team efforts. They note that patient safety is at risk when poor communication is in place. The leading cause for medication errors, treatment delays and wrong-site surgeries is communication failure.Illustration A shows the leading causes of death in the United States. This includes “preventable errors” as a cause.Incorrect Answers:treatment, medication errors and wrong side surgeryWhich of the following is true regarding osteoprotegerin (OPG)?It is secreted by osteoclastsIt increases bone resorptionBinds to prostoglandin E2 before stimulating osteoclastsOsteoprotegerin knock-out mice develop osteopetrosisBinds to and sequesters RANKLOsteoprotegerin is a decoy receptor for RANKL. Binding to RANKL causes decreased production of osteoclasts by inhibiting the differentiation of osteoclast precursors.Bone resporption/remodeling is a complex process regulated by a large variety of molecules. Molecules that have shown to inhibit osteoclasts include OPG, calcitonin, estrogen, TGF-B, and IL-10. Corticosteroids have been shown to decrease production of OPG, thereby enhancing osteoclast formation and longevity. Prolia, or denosumab, is a newly approved drug used to treat osteoporosis and has a mechanism of action similar to osteoprotegerin(inhibits binding of RANKL to RANK).Boyle et al. review osteoclast differentiation and activation. The authors state that targeted disruption of OPG causes increased osteoclastogenesis and/or activation resulting in osteopenia.Illustration A shows how OPG binds to RANKL inhibiting the stimulation of osteoclasts.Incorrect Answers:A 55-year-old woman has T-score -2.0 at the femoral neck. According to the World Health Organization Fracture Risk Assessment Tool (FRAX), she has a ten- year probability of sustaining a hip fracture of 1.5% and a ten-year probability of sustaining a major osteoporotic fracture of 8.9%. Which of the following statements is true regarding her antiresorptive therapy management?Antiresorptive therapy should be started based on her T-scoreAntiresorptive therapy should be started based on her risk of hip fracture aloneAntiresorptive therapy should be started based on her risk of major osteoporotic fracture aloneAntiresorptive therapy should not be startedAntiresorptive therapy should be started based on her risks of both hip fracture and major osteoporotic fractureThis patient has osteopenia. Assessment by FRAX shows that ten-year risk of hip fracture is less than 3% and her ten-year risk of major osteoporosis- related fracture is less than 20%. Therefore, antiresorptive therapy is not indicated at this time.According to the 2008 National Osteoporosis Foundation guidelines, pharmacologic treatment for osteoporosis should be considered if patients arepostmenopausal women or men greater than 50 years old AND meet one of the following criteria: (1) they have a prior hip or vertebral fracture, (2) they have a T score -2.5 or less at the femoral neck or spine, (3) they have a T score between -1.0 and -2.5 at the femoral neck or spine AND a 10-year risk of hip fracture greater than 3% or 10-year risk of major osteoporosis-related fracture greater than 20%.FRAX (World Health Organization Fracture Risk Assessment Tool) calculatesyear risk of fracture based on the following variables: age, sex, race, height, weight, BMI, history of fragility fracture, parental history of hip fracture, use of oral glucocorticoids, secondary osteoporosis and alcohol use to calculate 10-year risk of fracture.Unnanuntana et al. reviewed the assessment of fracture risk. Besides FRAX score and T-score, they discussed biochemical markers of bone formation and resorption, which are useful for monitoring the efficacy of antiresorptive / anabolic therapy, and may help identify patients at high risk for fracture.Ekman et al. reviewed the role of the orthopaedic surgeon in minimizing mortality and morbidity associated with fragility fractures. The surgeon should consider prescribing appropriate medications, physical therapy, assessing fall risk and preventing falls and changing lifestyle factors (exercise, smoking and alcohol).Illustration A shows the FRAX online tool (http://www.shef.ac.uk/FRAX/tool.aspx?country==9).Illustration B shows theclinical risk factors considered in FRAX calculation.Incorrect Answers:A 32-year-old runner sustains a trimalleolar left ankle fracture. She undergoes open reduction and internal fixation and is kept non- weightbearing after surgery. At 2 months, what changes will occur in the articular cartilage of both her knees as a result of her current weightbearing regimen?Cartilage thickening in the left (ipsilateral) knee and no change in cartilage thickness in the right (contralateral) kneeCartilage thinning in both kneesCartilage thinning in the left (ipsilateral) knee and no change in cartilage thickness in the right (contralateral) kneeCartilage thinning in the left (ipsilateral) knee and increased cartilage thickness in the right (contralateral) kneeIncreased cartilage thickness in both kneesAfter a period of off-loading, the off-loaded limb will experience cartilage thinning. The contralateral limb will not demonstrate any cartilage changes.Physiologic loading of cartilage increases proteoglycan synthesis and cell proliferation and is chondroprotective. Joint immobilization leads to cartilage thinning, tissue softening, and reduced proteoglycan content, leading to cartilage erosion. Joint overuse leads to cartilage damage (in vitro only).Hinterwimmer et al. examined cartilage atrophy after partial load bearingusing quantitative MRI. They found cartilage thinning in all knee compartments (greatest thinning, medial tibia; least thinning, patella). There was no change in cartilage morphology in the contralateral knee.Sun reviewed the relationship between mechanical loading and cartilage degeneration. In OA, cartilage breakdown occurs at the articular surface, and is then fueled by synovial proteases and cytokines. In RA, synovial cells and macrophages are the source of degradative enzymes and incite cartilage destruction.Milward-Sadler et al. examined mRNA levels following mechanical stimulation in normal and osteoarthritic chondrocytes. Normal chondrocytes showed increased aggrecan mRNA and decreased matrix metalloproteinase 3 (MMP-3) mRNA after stimulation. Thischondroprotective response was absent in osteoarthritic chondrocytes.Illustration A shows pro- and anti-inflammatory mechanisms of mechanical loading on chondrocytes. Underloading and overloading induce cartilage damage through pathways involving the upregulation of MMPs and ADAMTSs (ADAMTS, a disintegrin and metalloproteinase with thrombospondin motifs, or aggrecanase). Physiological loading blocks these increases.Incorrect Answers:A morbidly obese 40-year-old man is scheduled to undergo hemilaminectomy for resection of an painful osteoid osteoma of the T6 lamina. He is positioned prone on a Jackson table and localization is performed with intraoperative fluoroscopy prior to the start of the case. At close to the end of the case, intraoperative frozen section reveals only normal bone fragment from the resected lamina. A probe is placed and a cross-table lateral radiograph reveals that the T7 lamina was resected instead of T6. At this point, the surgeon shoulddo all of the following EXCEPTComplete the surgeryAbort the case and obtain further imagingApologize to the patient and familyFormally document the error in the operative reportInform the patient and family immediately after the operationFluoroscopic localization of the correct thoracic vertebra can be difficult in the obesepatient. Upon detection of wrong level surgery, he should not abort the case. Rather, he should perform the desired procedure at the correct site, and advise the patient and  family upon completion.Adverse events are inevitable. The correct action following wrong-site surgery is to perform the desired procedure at the correct site followed by frank and honest communication with the patient/family. Open, honest communication favorably affects patient behavior, health outcomes, patient satisfaction, and often reduces the incidence of medical professional liability actions. Thediscussion should include a disclosure of known facts and an explanation as to the likely cause, as well as ongoing treatment, follow up care, and prognosis.The AAOS Information Statement about Wrong Site Surgery identifies 3 treatment steps following discovery of an error during surgery under general anesthesia: Return the patient to his preoperative condition, perform the correct procedure at the correct site, and advise the patient and family of what occurred and the likely consequences, if any, of the wrong- site surgery.The AAOS Information Statement on Communicating Adverse Events states that the surgeon has an ethical and professional obligation to disclose the error to the patient and/or family. Disclosure should include what happened, why it happened, health implications, and what measures are being instituted to prevent recurrences.Incorrect Answers:All of the following are Standards of Professionalism relating to interactions with industry for practicing orthopaedic surgeons EXCEPT:Decline gifts from industry with a market value over $100 (unless they are medical textbooks or patient educational materials)Disclose to the patient any financial arrangements with industry that relates to the patient's treatmentAccept no direct financial inducements from industry for utilizing a particular implantDisclose any relationship with industry to colleagues who may be influenced by your workDecline to participate in industry sponsored non-CME courses orconferencesThe AAOS has adopted the Standards of Professionalism (SOP). These SOP’s establish mandatory, minimum levels of acceptable conduct for fellows and members of the AAOS to engage in relationships with industry. There are 17 standards with relation to industry. Answer choice 5 is not a SOP as surgeons are allowed to participate in or consult in meetings that are conducive to the effective exchange of information. The SOP also stipulate that tuition, travel, and modest hospitality (including meals and receptions) are allowed to attend an industry-sponsored non-CME course.A prospective randomized trial is conducted to test the efficacy of Vitamin C versus placebo in treating patients who develop chronic regional pain syndrome (CRPS) after distal radius fractures. At first follow-up, the rates of CRPS are 1% and 9% in the study and placebo group, respectively. Which statistical test is most appropriate to determine significance?Single factor analysis of varianceChi-square testStudent t-testMann-Whitney rank sum testWilcoxon rank sum testIn the study provided, we need to determine whether distributions of categorical variables differ from one another. The appropriate study is the chi- square test.Data can be classified as numerical (continuous) or categorical (proportional). Responses to such questions as "What is your major?" or Do you own a car?" are categorical because they yield data such as "biology" or "no." In contrast, responses to such questions as "How tall are you?" or "What is your G.P.A.?" are numerical. When comparing two independent means from numeric data, a t-test is performed. However, if categorical data is being compared, the chi- square test will determine if the proportions are really different.Kocher et al. review basic clinical epidemiology and biostatistics relevant to orthopaedic surgery. Amongst other things, they describe that data can be summarized in terms of measures of central tendency, such as mean, median, and mode, and in terms of measures of dispersion, such as range, standard deviation, and percentiles.Illustration A shows an algorithm for determining which test to use for varying data. Incorrect Answers:distributed.A 35-year-old patient is involved in a motor vehicle accident and sustains multiple fractures including a closed comminuted proximal meta-diaphyseal tibia fracture. The surgeon is considering bridge plating the fracture using a minimally invasive approach. Which of the following is true regarding bridge plating?A locked plate construct (locked screws) or hybrid construct (locked and non- locked screws) is necessary.Periosteal stripping is performed through two incisions proximal and distal to the fracture.Bridge plating is performed following direct reduction of the fracture.AO Type A diaphyseal fractures are best treated with this technique.Bridge plating with a long working length creates a flexible, axially stable construct.In bridged plating, only the most proximal and distal screw holes are filled. This creates a flexible, axially stable construct.Bridge plating is applicable to all long-bone fractures with complex fragmentation and where intramedullary nailing or conventional plate fixation is not suitable. The construct preserves the blood supply to the fracture fragments as the fracture site is undisturbed during the operative procedure. It provides RELATIVE stability, allowing for some motion at the fracture site, leading to callus formation and secondary bone healing. The construct is FLEXIBLE because of increased distance between the 2 screws closest to the fracture (long working length), allowing for stress distribution and permitting more motion at the fracture site. The construct is also AXIALLY STABLE because the plate acts as an extramedullary splint and resists axial compression.Livani et al. advocate using an anterior or antero-lateral approach for minimally invasive plating of the humerus. They recommend that distal access is obtained first, allowing identification of the lateral antebrachial cutaneous nerve. For distal fractures, they recommend extending the plate down to the lateral column.Apivatthakakul et al. defined minimally-invasive plate osteosynthesis (MIPO) danger zones from the lateral epicondyle. They found the musculocutaneous nerve averaged 18- 43% of the humeral length, the danger zone for the radial nerve averaged 36-59% of the humeral length, and the most dangerous screws that penetrated or touched the radial nerve lay 47-53% of the humeral length.Illustration A shows a distal tibia fracture. Illustration B shows radiographs 5 months after bridge plating of this fracture. There is callus formation, characteristic of indirect bone healing.periosteal blood supply is critical.Which of the following components of bone is most responsible for compressive strength?Type I collagenOsteocalcinProteoglycansOsteonectinOsteopontinProteoglycans, in addition to calcium hydroxyapatite [Ca10(PO4)6(OH)2], are most responsible for providing compressive strength.Bone is composed of both organic and inorganic components. Inorganic components include calcium hydroxyapatite and osteocalcium phosphate. Organic components include collagen, proteoglycans, matrix proteins, cytokines and growth factors. While Type I collagen is responsible for providing the tensile strength of bone, proteoglycans and calcium hydroxyapatite [Ca10(PO4)6(OH)2] are most responsible for providing compressive strength. Proteoglycans contain a core protein with variousnumbers of covalently attached side chains of glycosaminoglycans. In addition to providing compressive strength, they are also responsible for binding growth factors and inhibiting mineralization.Knothe et al. review the osteocyte. They discuss that osteocytes are the most abundantcells in bone, are actively involved in maintaining the bony matrix, and may act as mechanosensors.Illustration A shows a proteoglycan aggregate, which can form when individual molecules link onto a chain of hyaluronic acid.Incorrect Answers:A prospective, randomized controlled trial of 150 patients undergoing total hip arthroplasty is performed to test whether repair of the capsule during a posterior approach reduces post-operative dislocations in the first three months. The study found no difference in dislocation rate if the capsule was repaired versus not repaired (p =.34). Subsequently, a multicenter follow-up study of 2000 patients showed that repairing the capsule led to a decreased dislocation ratein the first three months (p = .03). Assuming the second study reflects reality, which of the following errors occurred in the first study?Observer biasType-II errorAlpha errorType-I errorConfounding errorIn this situation, the null hypothesis was accepted when it should have been rejected.This is a type-II error.A study can have two types of errors. Type-I errors, or alpha errors, occur when the null hypothesis is rejected when it should have been accepted. The alpha level refers to the probability of a type-I error. By convention, the alpha level of significance is set at 0.05, which means that we accept the finding of a significant association if there is less than a one in twenty chance that the observed association was due to chance alone. Type-II errors, or beta errors, occur when the null hypothesis is accepted when it should be rejected. Thisoften occurs when studies are underpowered. In the example above, the null hypothesis is that repair of the capsule does not reduce dislocations within the first three months. Since the first study did not show a statistically significant difference, the null hypothesis was accepted. Since a more powered study showed that repair of the capsule does reduce dislocations, the null hypothesis should have been rejected in the initial study (if it was adequately powered).Fosgate et al. review the importance of sample size calculations when performing research. They state that sample size ensures statistical significance if the subsequent data collection is perfectly consistent with the assumptions made for the sample size calculation (assuming power was set as50% or greater).Illustration A shows the difference between type-I and type-II errors. Video V is a lecture discussing statistical definition review of PPV, NPV, sensitivity and specificity.Incorrect Answers:that properly constructed studies attempt to avoid.Which of the following is a potential cause of fretting corrosion?The micromotion at the femoral head-neck junction in a modular total hip replacementA stainless-steel cerclage wire is in contact with a titanium-alloy femoral stemFriction between polyethylene liner and femoral head leading to osteolysisThe formation of pits within a stainless-steel plate and the subsequent release of metal ionsThe formation of an adherent oxide coating on titanium implantsMicromotion at the femoral head-neck junction can lead to fretting corrosion, one of the most common causes of failure of a modular implant.Modular components give surgeons excellent intraoperative flexibility, but are susceptible to various types of corrosion. While titanium and cobalt-chrome contain a protective surface oxide layer, continued micromotion at the modular junction may disrupt the protective layer leading to fretting corrosion, defined as micromotion at contact sites under load. This may eventually lead to a painful synovitis that necessitates a revision procedure.Srinivasan et al. review modularity in total hip arthroplasty. Amongst other things, they discuss the modularity of the femoral head/neck junction, describing the morse taper interlocking system that provides both axial and rotational stability.Illustration A shows an example of corrosion at the head/neck junction of a total hip arthroplasty.Incorrect Answers:Which of the following situations is most likely to decrease sentinel event errors?Physician and nurse training is lengthened by 20%Resident hours are decreased to 55 hours per weekAn environment is created where all members of the healthcare team feel empowered to express their concerns and beliefsHolding individuals responsible for errors in clinical judgementPhysicians and nurses are assigned to a smaller number of patientsCreating an environment where all members of the healthcare team feel empowered to express their beliefs increases communication, the key element in decreasing sentinel events.Research has shown that 70% of sentinel event errors are caused by improper communication. Specific ways to improve communication include effective clinical handover between shifts and breaking down the "hierarchy" so that all members of the team can discuss their expectations and concerns. Barriers to effective communication include distractions, cultural differences, power distance relationships, time pressures, and lack of organization.Leonard et al. describe specific clinical experiences in the application of surgical briefings, properties of high reliability perinatal care, the value of critical event training and simulation, and benefits of a standardised communication process in the care of patients transferred from hospitals to skilled nursing facilities. They recommend embedding standardized tools and behaviors to bridge differences in communications styles between clinicians.Incorrect Answers:Which of the following side effects is most strongly associated with the use of NSAIDs?Hepatic dysfunctionRenal impairmentProlonged QTcSeizuresHematuriaAll NSAIDs have the potential to cause serious renal impairment.NSAIDs work by inhibiting the cyclooxygenase pathway (COX), which is comprised of the COX-1 and COX-2 pathways. The COX-1 pathway is involved in prostaglandin E2– mediated gastric mucosal protection and thromboxane effects on coagulation, while the COX-2 pathway is mainly involved with the modulation of pain and fever without effect on platelet function. While selective COX-2 inhibitors have a decreased side effect profile, all NSAIDShave the potential to cause renal impairment and their use should be limited in patients with underlying renal disease.Horlocker et al. review multimodal pain management in the perioperative setting of a total joint arthroplasty. Specifically, they note that NSAIDs should be used cautiously in patients with underlying renal dysfunction who are to undergo a procedure with major blood loss.Griffin et al. reviewed 1,799 patients hospitalized for acute renal failure. They found that NSAIDs increased the risk of renal failure by 58% and that NSAID use resulted in 25 excess hospital admissions per 10,000 years of use.Illustration A shows the COX pathways and their inhibition by NSAIDs. Incorrect Answers:It is recommended that invasive dental work be completed prior to the initiation of which of the following medications?GlucosamineCholecalciferolLevothyroxineTeriparatideBisphosphonatesBisphosphonate therapy combined with invasive dental work increases the risk for development osteonecrosis of the jaw.Bisphosphonates are a class of drugs that prevent bone mass loss by inhibiting osteoclast resorption. They are used in the treatment of vertebral compression fractures, non- vertebral fragility fractures, osteogenesis imperfecta, multiple myeloma, and avascular necrosis. Because bisphosphonates have been associated with osteonecrosis of the jaw, it is suggested that all invasivedental work be completed prior to initiation of treatment.Pazianas et al. (2011) review the safety profile of bisphosphonates. Specifically, they cite gastrointestinal discomfort, atypical femur fractures, osteonecrosis of the jaw, ocular inflammation, and musculoskeletal pain as common side effects. They state there is limited evidence surroundingbisphosphonate's association with esophageal cancer and atrial fibrillation.Pazianas et al. (2007) reviewed 11 publications that reported 26 cases of osteonecrosis of the jaw following initiation of bisphosphonate treatment. Age>60 years, female sex, and previous invasive dental treatment were the most common characteristics of those who developed ONJ.Illustration A shows the various bisphosphonates and their mechanisms of action. Illustration B shows an example of osteonecrosis of the jaw, a side effect that has been linked to bisphonphonate treatment.Incorrect Answers:Figures A and B show radiographs of a 24-year-old female with a soccer injury. A physical examination reveals an isolated, closed injury with no clinical features of neurovascular injury or compartment syndrome. She has been consented to be treated with intramedullary nail fixation. A pre-operative note by the anaesthesiology team makes reference to the patients fair skin and natural red-hair color. How will this information affect the post-operative management of this patient?Longer duration of anticoagulation due to increased risk of DVTAvoiding anticoagulation medications due to increased risk of bleedingRequire higher dosages of post-operative analgesiaLonger period of non-weight bearing on surgical limbAvoiding opioids due to higher risk of unrecognized allergiesFemale patients with natural red-hair may require higher dosages of post- operative analgesia compared to other hair types.Melanocortin-1-receptor (MC1R) is one of the key proteins involved in hair color and skin tone. Mutations of the MC1R alleles can render this protein non- functional, which results in a phenotype of red-hair and fair skin. Mutations of the MC1R have shown to modulate the pain response and opioid efficacy in these patients. Women are more commonly affected and often require more anaesthetic and higher dosages of opioid to achieve comparable MAC level and pain-relief, respectively, as women with other hair types.Liem et al. showed that a greater concentration of induction and maintenance agents (sevoflurane and desflurane, respectively) were required to sustain comparable MAC levels in red-haired patients as dark haired patients.Fillingim et al. reviewed the affect of gender, sex and pain. They concluded there is a biopsychosocial element of pain that is perceived differently by men and women. In terms of postoperative and procedural pain, the outcome might be more severe in women than men.Delaney et al. looked at the involvement of the melanocortin-1 receptor in acute pain in mice. They found that while the MC1R is better known as a gene involved in mammalian hair colour, it was shown to be involved in the pain pathway of inflammatory but not neuropathic origin. Mutations of MC1R showed increased tolerance to noxious pain stimulus in mice.Figures A and B are AP and lateral radiographs of a left tibia. There is a low energy, distal third shaft fracture with no cortical apposition on the AP view.Incorrect Answers:Which of the following medications used for thromboprophylaxis following orthoapedic surgery is a direct inhibitor of factor Xa?DextranRivaroxaban (Xarelto)CoumadinFondaparinux (Arixtra)AspirinRivaroxaban (Xarelto), an oral anticoagulant, is a direct inhibitor of factor Xa.Rivaroxaban (Xarelto) is a member of a new class of oral, direct (antithrombin- independent) factor Xa inhibitors, which restrict thrombin generation both in vitro and in vivo. Inhibition of Factor Xa interrupts the intrinsic and extrinsic pathway of the blood coagulation cascade, inhibiting both thrombin formation and development of thrombi.Eriksson et al. compare rivaroxaban to enoxaparin for the prevention of symptomatic venous embolism following total hip arthroplasty. Major venous thromboembolism occurred in 4 of 1686 patients (0.2%) in the rivaroxaban group and in 33 of 1678 patients (2.0%) in the enoxaparin group. Additionally, major bleeding events were similar between the two groups.Illustration A shows the mechanisms of action of various agents used for thromboprophylaxis.Incorrect Answers:as Protein C and Protein S.The origin of bovine derived grafts is particularly important to which of the following religious groups?ChristianityIslamHinduismBuddhismJudaismThe origin of bovine-derived surgical implants should be discussed in further detail with patients ascribing to Hinduism.Patients come from a variety of religious backgrounds. Depending on a patient’s religion, the origin of surgical implants may have implications for their use. In Hinduism, bovine animals are considered sacred. Use of cow by- products is considered purifying in nature. Subsequently, the origin of bovine derived implants should be discussed with patients ascribing to Hinduism.Easterbrook et al. evaluated the utility of porcine and bovine surgical implants amongst those of Jewish, Muslim and Hindu faiths. Hindu religious leaders, who were surveyed, did not approve of the use of bovine surgical implants.Enoch et al. evaluated the acceptability of biological products amongst various religious groups. The Hindu religious leaders were found to not have an objection to the use of biological implants derived from cows.Illustration A shows a clinical photo of a fetal bovine derived dermal substitute. Incorrect Answers:Immunological testing of anti-cyclic citrullinated peptide antibodies (anti- CCP) is most commonly used for the diagnosis and prognosis of which immunological condition?Ankylosis spondylitisRheumatoid arthritisPsoriatic arthritisSystemic lupus erythematosusReiter's syndromeAnti-cyclic citrullinated peptide antibodies (anti-CCP) are commonly used as a marker for the diagnosis and prognosis of rheumatoid arthritis (RA).Immunological studies are commonly performed to investigate cases of suspected rheumatoid arthritis. Rheumatoid factor has historically been used as a primary marker for RA. However, in more recent years, the use of anti- CCP antibodies has shown to be as sensitive as, and more specific than, rheumatoid factor (RF) in early and fully established disease. In general, anti-CCP assays equate to a sensitivity of 50-75% and a specificity of 90-95%. High levels of anti-CCP have been shown to be indicative of a more erosive disease process and may be detected before the onset of arthritis.Gardner and Kadel reviewed the laboratory studies most commonly used in rhuematologic diseases. Standard ordering for clinically suspected RA include Rf, anti- CCP, ESR/CRP as well as other markers of autoimmune diseases such as antinuclear antibodies, anticardiolipin antibodies and lupus anticoagulant, HLA-B27, and uric acid levels.Illustration A shows the sensitivity and specificity of anti-CCP vs. RF in a variety of autoimmune diseases.Incorrect Answers:Vitamin C has been shown to decrease the likelihood of which of the following complications following surgery on the foot and ankle in non-diabetic patients?NonunionComplex Regional Pain Syndrome, type IIMalunionComplex Regional Pain Syndrome, type IWound infectionVitamin C has been shown to decrease the likelihood of developing complex regional pain syndrome (CRPS), type 1, when given post-operatively to patients undergoing foot and ankle and wrist surgery.CRPS is a frequent post-operative complication, with rates varying from 10-37%. Type I CRPS does not have an identifiable nerve lesion, while type II has an identifiable nerve lesion. Multiple studies have shown that vitamin C decreases rates of CRPS following distal radius fractures, and more recently, the same has been shown following foot and ankle surgery. While the exact mechanism of CRPS is unknown, vitamin C has been shown to reduce lipid peroxidation, scavenge hydroxyl radicals, protect the capillary endothelium, and inhibit vascular permeability. All of these characteristics of vitamin C may play a role in modulating the pain pathway.Zollinger et al. perform a double-blind, prospective, multicenter trial where416 patients with 427 wrist fractures were randomly allocated to treatment with placebo or treatment with 200, 500, or 1500 mg of vitamin C daily for fifty days. The prevalence of complex regional pain syndrome was 2.4% in the vitamin C group and 10.1% in the placebo group.Besse et al. compare two groups of patients undergoing surgery on the foot and ankle to determine the effect of vitamin C on the development of CRPS, type I. CRPS type I occurred in 18 cases (9.6%) in the group not given vitamin C, and 4 cases (1.7%) in the group given vitamin C.Illustration A shows an example of a limb affected by CRPS. Note the increased swelling, a common physical exam finding in patients afflicted with the disease.Incorrect Answers:A 25-year-old Spanish speaking male presents to the emergency department 6 hours after sustaining the injury seen in Figure A. He is grossly intoxicated and screaming in pain. Physical examination reveals a closed injury with overlying muscular compartments that are extremely firm to palpation. After sedating the patient, measurements of the intracompartmental pressures were all found to be>75mmHg. His wife is Spanish speaking and expected to arrive to the hospital in 2-3 hours with a relative to help with translation. No medical translator isavailable. You attempt to outline the risk and benefits of surgery to the patient, but the he repeatedly interrupts you and yells out ,"No surgery!". An English-Spanish speaking friend is with the patient and says that he has known the patient for over 2 years and will help with any decision making. What would be the next most appropriate step in the management of this patient?Delay surgery to monitor the patient for impending compartment syndromeProceed with surgery with urgent fasciotomy after documenting the necessity of treatment without consentDelay the surgery until the wife arrives and able to give informed consent with the aid of a translatorProceed with surgery for urgent fasciotomy after obtaining informed consent from the patients friendRespect the patients autonomy and reassess the patient in the morning when he demonstrates capacity to accurately comprehend the proposed treatmentThis patient is presenting with compartment syndrome of the right tibia. In a situation of required surgery for limb threatening injury without available legal consent the surgeon should confirm and document the necessity of care with a fellow colleague.Physicians are responsible for whether a patient is able to reasonably understand their medical condition and the nature of any proposed medical procedure, including the risks, benefits, and available alternatives. If the patient lacks this capacity, disclosure imposed by the doctrine of informedconsent are excused because irreparable harm that may result from the physician’s hesitation to provide treatment. Detailed documentation is also important. In addition, the attending physician should contact the Risk Management Dept at the hospital for support prior to surgical intervention or have a medical translator involved to ensure information is being translated properly.Katz et al. reviewed the medical decision making process of Hispanic people. They showed that Hispanic people are more likely to permit their physician to take the predominant role in making health decisions compared to Non- Hispanic people.Figure A shows a comminuted tibia and fibula fracture. Incorrect AnswersA Spanish speaking child sustained the injury seen in Figure A after a fall at school. He was casted in the emergency department without the assistance of an interpreter and advised to return to see an orthopaedic surgeon in 1 week. However, the family returns to the emergency department with the child 3 months later, still in the cast. What is the most likely reason the child did not attend the recommended orthopaedic follow-up visit.?The child is a victim of neglectThe child had no symptoms of painHe was allowed to return to school wearing the castConcerns of costFollow-up instructions were not effectively communicatedThe most likely reason the child did not attend the recommended orthopaedic follow-up visit was a language barrier preventing effective communication of the intended follow-up instructions.Communication skills and cultural competence is a key element in good orthopaedic care. Poor communication can often lead to devastating outcomes. In this example, poor communication resulted in this patient being lost tofollow-up. Language barriers must be accommodated and alternative methods of communication must be utilized.Levinson et al. examined how patients present their medical issues in clinical encounters and how physicians respond to these clues in routine primary care and surgical settings. They showed that good communication relies mostly on the physicians ability to identify patient clues within the clinical encounter.Poor communication between the physician tended to delay clinical visits, poor follow-up and unsatisfactory outcomes.Figure A is an AP radiograph of the elbow in a skeletally immature patient. Figure B is a lateral radiograph of the elbow with a posterior fat pad sign, suggestive of an occult fracture.Incorrect Answers:A 25-year-old female presents to the emergency room within increasing left shoulder pain after walking into a door 5 months ago. She previously sustained a femoral fracture 2 years ago after tripping on a rug. Relevant skeletal survey radiographs and tissue biopsy results are shown in Figures A through D. Laboratory investigations show normal glomerular filtration rate and creatinine clearance. Dual energy x-ray absorptiometry (DEXA) scan shows T-score of -1.4 and-1.2 at the hip and lumbar spine, respectively. Which of the following laboratory values in Figure E most likely reflects this patient's condition?ABCDEThis patient has primary hyperparathyroidism. Laboratory investigations are likely to show elevated serum intact parathyroid hormone (PTH), alkaline phosphatase (ALP) and ionized serum calcium, and low serum phosphate.Primary hyperparathyroidism is most commonly caused by a single adenoma (80-90%). Besides the signs and symptoms of hypercalcemia, patients presentwith calcification of menisci and articular cartilage, erosions in hand bones, "salt and pepper skull", and brown tumors (osteoclastomas), which appear as lytic regions expanding the cortex and causing pathological fractures, so named because of hemosiderin deposition.Singhal et al. reviewed primary hyperparathyroidism. They advocate routine serum calcium levels for patients with pathologic fractures. If this is elevated, total and ionized calcium and intact PTH levels should be obtained. They feel that surgery for orthopaedic stabilization and parathyroidectomy should be performed simultaneously for better outcome.Mankin et al. reviewed metabolic bone disease. They suggest that patients with mild disease with normal calcium levels do not require treatment. For patients with high calcium levels, treatment should include maintenance of fluid balance, localization and removal of the adenoma, bony stabilization, and medications (calcitonin, estrogen, bisphosphonates, and calcimimetics such as cinacalcet).Figure A is an AP radiograph showing a lytic expansile lesion with pathological fracture in metadiaphyseal region of left humerus with similar lesion in thefifth posterior rib. Figure B is an AP radiograph showing a lytic expansile lesion in the third metacarpal of the right hand and the fifth metacarpal of the left hand. Figure C is a low power micrograph of a brown tumor demonstrating a central zone of bone resorption, and filling with fibroblastic tissue, with a peripheral rim of osteoid production. Figure D is a high power micrograph of a brown tumor. In areas of bone resorption, there are numerous osteoclast-like giant cells amidst a fibrous stroma. This is unlike a true giant cell tumor, which lacks a fibrogenic stroma.Incorrect Answers:and impaired 1,25-dihydroxyvitamin D production by the diseased kidneys. This patient has normal renal function. Answer 3: Elevated PTH, ALP, serum calcium and phosphate occur in tertiary hyperparathyroidism. This again occurs in chronic renal disease after prolonged chronic secondary hyperparathyroidism or after renal transplantation, where the parathyroid glands become autonomous and PTH levels do not normalize. This patient has normal renal function.elevated.FOR ALL MCQS CLICK THE LINK ORTHOMCQ BANK

Strain is defined as the change in length/original length (L) and is created by a deformation of a material from an applied force.The mechanical environment at the fracture site has a major influence on fracture healing. Granulation tissue can withstand higher strain, which stabilizes the mechanical environment and forms a scaffold on which cartilage and bone eventually form; this occurs after strain decreases incrementally. Optimal healing, however, depends on duration, rate, timing and type of mechanical influence. Bone is formed by osteoblasts that are adapted to the very low strains of over 1% change in length. Osteoblast synthesis and proliferation is stimulated at uniaxial strain of between 0.3% and 2.8%. It is known that limited inter-fragmentary movement of 0.2 mm to 1 mm is optimal for fracture healing, resulting in promotion of callus and increase in rigidity. Excessive movement, on the other hand, prolongs fracture healing. Researchers have identified that tissue strain of 2% is suitable for primary bone healing and secondary bone healing takes place at tissue strain of 2-10%. Strain of 10-100% results in fibrous tissue formation and 100% strain to non-union. This is known as Perren's theory.Stokes published a review article on the effects of stress on bone healing and growth, and notes the importance of the 'Hueter-Volkmann Law' (growth is retarded by increased mechanical compression, and accelerated by reduced loading in comparison with normal values) in bone growth. Stokes also notes that sustained compression of physiological magnitude inhibits growth by 40% or more, while distraction increases growth rate by a much smaller amount.Illustration A shows an example of a stress-strain curve, with several key definitions labeled on the diagram.Incorrect Answers:

Sickle cell crises resulting in bone infarcts can be difficult to differentiate from acute osteomyelitis with physical exam and plain radiographs alone. This child is undergoing a bone infarct as confirmed by his radionuclide scans. Skaggs et al. reviewed 79 cases of acute extremity pain in sickle cell patients. Radionuclide bone marrow and bone scan were used to differentiate osteomyelitis from bone infarct. Four cases of infection were diagnosed by normal uptake on the bone marrow scan and abnormal uptake on the bone scan. These cases were confirmed osteomyelitis by positive culture. Seventy cases were diagnosed as bone infarct by decreased uptake on the bone marrow scan and abnormal uptake on the bone scan. Chambers et al. reviewed the charts of 2000 known sickle cell patients. Fourteen patients had an episode of osteomyelitis or septic arthritis. Radiographs and bone scans were not helpful in differentiating infection from an acute bone infarct. Salmonella was the most frequent organism cultured from the osteomyelitis cases. The authors recommend bone aspiration or biopsy in a sickle cell patient with extremity pain, swelling, and a fever greater than 38.2 degrees C.

The corona mortis ('crown of death') is a common vascular anastomosis between the external iliac or inferior epigastric vessels and the obturator vessels (a branch of the internal iliac system). It is located on the posterior aspect of the superior pubic ramus and is highly vulnerable during anterior pelvic approaches.

A complete posterior root tear of the medial meniscus disrupts the circumferential hoop stresses of the meniscus, resulting in radial extrusion. This functional incompetence alters tibiofemoral joint contact pressures and areas to levels biomechanically equivalent to a total meniscectomy, predisposing the patient to rapid articular cartilage degeneration.

The corona mortis is a vascular anastomosis between the external iliac (or inferior epigastric) vessels and the obturator vessels. It is located on the posterior aspect of the superior pubic ramus and is at high risk during the Stoppa approach.

Pudendal nerve neuropraxia is a well-known complication of hip arthroscopy caused by compression against a poorly padded or malpositioned perineal post. It typically presents with groin, perineal, and genital numbness or dysfunction.

The anterolateral approach utilizes the internervous plane between the lateral compartment (fibularis tertius, innervated by the superficial peroneal nerve) and the anterior compartment (extensor digitorum longus, innervated by the deep peroneal nerve).

The pectoralis major tendon twists 180 degrees before inserting on the humerus. This twisting causes the sternal head to insert both proximal and deep to the clavicular head insertion.

The axillary nerve wraps around the surgical neck of the humerus approximately 5 to 7 cm distal to the lateral edge of the acromion. Care must be taken not to place retractors or plate screws blindly in this danger zone.

Camptomelic dysplasia is caused by a heterozygous loss of function of the Sox9 gene. The alternatives have genetic causes, but are not linked to Sox9. Cleidocranial dysplasia is related to a defect in Cbfa-1 (Osf-2, Runx2). Schmid metaphyseal chondrodysplasia is related to Type X collagen. Fibrous dysplasia is related to a defect in the alpha subunit of stimulatory guanine-nucleotide-binding protein (Gs). Achondroplasia is related to a defect in fibroblast growth factor receptor 3.

The patient has the classic symptoms of a pulmonary embolism. Symptoms of pulmonary embolism of polymethylmethacrylate (PMMA) following vertebral augmentation may occur with a delay. A symptomatic pulmonary embolism following vertebroplasty can occur either by migration of acrylic or the migration of fat and bone marrow cells. The MRI scan reveals a new superior endplate fracture involving L2. With this now being the third consecutive vertebral compression fracture in 2 months, one must be suspicious that these represent pathologic fractures, rather than osteoporosis. Risk factors for venous thromboembolic disease include increasing age, prolonged immobility, surgery, trauma, malignancy, pregnancy, estrogenic medications (eg, oral contraceptive pills, hormone therapy, tamoxifen [Nolvadex]), congestive heartfailure, hyperhomocystinemia, diseases that alter blood viscosity (eg, polycythemia, sickle cell disease, multiple myeloma), and inherited thrombophilias. In addition to the risk associated with embolization of PMMA, the patient has been immobile for 7 days and was ultimately diagnosed with multiple myeloma.Which key factor that induces osteoclastogenesis is secreted by osteoblasts in response to inflammatory stimuli?Osteoprotegerin (OPG)Tumor necrosis factor (TNF)Insulin growth factor-1 (IGF)Bone morphogenetic protein (BMP)Receptor activator of nuclear factor kappa-B ligand (RANKL)Corrent answer: 5Osteoclasts are derived from cells of the monocyte/macrophage lineage. They are multinucleated and develop by fusion of mononuclear precursors, a process that requires receptor activator for nuclear factor kappa-B ligand (RANKL) and macrophage-colony stimulating factor (M-CSF). RANKL is secreted by osteoblasts in response to inflammatory signals and is a key component of inflammation-mediated osteolysis. OPG binds to and sequesters RANKL, thus inhibiting osteoclast differentiation and activity.BMP and IGF-1 are potent regulators of osteoblast differentiation and activation. TNF is a cytokine secreted by macrophages and degranulating platelets infiltrated in the fracture site and impacts a variety of cells, not osteoclasts.A prospective outcome study is performed at a single institution to analyze the potential differences in treating intertrochanteric hip fractures with a plate/screw device versus an intramedullary device. No specific randomization is performed because an equal number of surgeons have preferences for the use of one of these devices and they are allowed to continue their preferred method. Hip- specific and general health-related outcome measures are used, an excellent follow-up rate of 85% of the patients at 2 years is accomplished, and there appears to be results that favor the intramedullary device but the confidence intervals are wide. This study would be considered to carry what level of evidence?IIIIIIIVVThis is a prospective comparative study but is not randomized or blinded andis therefore a Level II therapeutic study. To qualify as Level I, it would need to be a high- quality randomized trial with narrow confidence intervals regardless of a significant difference or no difference in outcomes. Level III would becase-control studies or retrospective comparisons. Level IV is case series and Level V is expert opinion.The fracture seen in Figures A and B is most likely to occur in which of the following growth plate zones?Resting zoneProliferative zoneZone of maturationZone of degenerationZone of provisional calcificationPhyseal fractures typically occur through the zone of provisional calcification. Answers 3-5 are all part of the hypertrophic zone which is labeled "D" on the histologic illustration A. Illustration B shows the relationship of the physeal zones to the epiphysis and metaphysis of a growing bone. However, the stress concentration is greatest in the sub-layer where there is a transition from the soft cartilagenous physis to the harder calcific metaphysis.As discussed in the review by Ballock and O'Keefe, the growth plate is a remarkable portion of the skeleton that requires precise coordination between multiple endocrine, paracrine, and autocrine signaling systems. While fractures can occur in any portion of the growth plate, the zone of provisional calcification is the most common.Since the adoption by the American Academy of Orthopaedic Surgeons in 1997 of the presurgical protocol in which the surgeon signs the surgical site and the mandate for this protocol by the Joint Commission on the Accreditation of Healthcare Organizations (JCAHO)in 2003, the total number of wrong-site surgeries reported per year in the United States hasincreased.decreased.decreased for orthopaedic surgery but stayed the same for other surgeries.remained the same.only improved for hospital-based surgery.Despite the initiatives by the American Academy of Orthopaedic Surgeons and theJCAHO, the number of reported cases of wrong-site surgery has continued to increase yearly since 1997. Because reporting of these events is not mandated by JCAHO, it is possible that the continued increase is due to a greater awareness of the problem and thereby a greater level of reporting. The U.S. estimates are 12.7 wrong-site surgeries per million cases performed. Orthopaedic surgery and podiatry are the most common specialties associated with wrong-site surgery (41%) followed by general surgery (21%), neurosurgery (14%), and urologic surgery (11%).The use of evidence-based studies among professions associated with health care, including purchasing and management, is known asdecision analysis.cost-utility analysis.cost-benefit analysis.cost-effectiveness analysis.evidence-based health care.Evidence-based health care extends the application of the principles of evidence-based medicine to all professions associated with health care. This concept is becoming more important because data will be used by the different parties for their decision making (policy makers, health insurances, hospitals, doctors, and the public). Cost-benefit analysis refers to the conversion of effects into the same monetary terms as the costs and compares them. Cost- effectiveness analysis refers to the conversion of effects into health terms and describes the costs for some additional health gain (eg, cost per additional event prevented). Cost-utility analysis refers to the conversion of effects into personal preferences (or utilities) and describes how much it costs for some additional quality gain (eg, cost per additional quality-adjusted life-year).Decision analysis refers to the application of explicit, quantitative methods to analyze decisions under conditions of uncertainty.All of the following medications have been associated with an increased risk of osteoporosis EXCEPT:Selective serotonin reuptake inhibitors (SSRI)GlucocorticoidsNon-steroidal anti-inflammatories (NSAIDs)PhenytoinProtease inhibitorsNumerous drugs are associated with an increased risk of osteoporosis inadults, including oral corticosteroids, androgen-deprivation therapy, aromatase inhibitors, protease inhibitors, selective serotonin reuptake inhibitors,prolactin-raising antiepileptic agents and many cytotoxic agents.Additionally, a number of disease states are associated with osteoporosis, including endocrinopathies such as hyperparathyroidism, thyrotoxicosis and type I diabetes, hypogonadism, chronic glucocorticoid therapy, malnutrition, malabsorption states, chronic immobilization, rheumatoid arthritis, alcoholism, vitamin D deficiency, and multiple myeloma.NSAIDs have not been shown to increase risk of osteoporosis.A 65-year-old woman with rheumatoid arthritis is unable to actively extend her index, middle, ring, and little fingers secondary to tendon rupture. In performing a flexor digitorum sublimis (FDS) of the middle/ring finger to extensor digitorum communis (EDC) transfer to restore active metacarpophalangeal (MCP) joint extension, the FDS should be passedulnarly, around the ulna in a dorsal direction.radially, around the radius in a dorsal direction.through the interosseous membrane.through the intermetacarpal spaces between the index, middle, ring, and little fingers.through the lumbrical canals of the index, middle, ring, and little fingers.Corrent answer: 2Although the early use of FDS as a transfer to restore finger extension in patients with radial nerve palsy was performed by passing the tendon through the interosseous membrane, Nalebuff and Patel later modified this procedure for the rheumatoid arthritis patient by passing the FDS radially, around the radius in a dorsal direction. They felt that this provided a number of advantages, including: 1. technical ease, 2. avoidance of synovial disease on the dorsum of the wrist, and 3. correction of ulnar deviation of the fingers through the line of pull from the radial side of the forearm.Based on the clinical photograph, radiographs, and biopsy specimen shown in Figures 68a through 68d, what is the most likely diagnosis?Calcium pyrophosphate deposition diseaseBacterial infectionFungal infectionGoutGiant cell tumorThe patient has gout. Unfortunately, gout may mimic several conditions affecting the small joints of the hand, including infection. The histologic specimen shows negatively birefringent intracellular rods consistent with gout. The histology rules out giant cell tumor and calcium pyrophosphate deposition disease.An otherwise healthy 30-year-old man undergoes right shoulder arthroscopic Bankart repair under regional anesthesia using an interscalene brachial plexus block. In the recovery room, he reports mild difficulty breathing and his chest radiograph shows a high riding diaphragm on the right side. His peripheral oxygenation is 97% on 2 liters of oxygen by nasal cannula. What is the most appropriate management?Continued observation and monitoringObtain arterial blood gas measurementsObtain emergent spiral CT scan to assess for pulmonary embolismInsertion of a chest tubeAirway control and, if necessary, endotracheal intubationBecause the phrenic nerve lies in close proximity to the site of anesthetic injection, temporary hemidiaphragmatic paresis is a very common side effect of interscalene brachial plexus block. Pulmonary function and chest wall mechanics may be slightly compromised, but can easily be compensated in a healthy patient. Therefore, withsufficient oxygenation, aggressive assessments or treatments such as arterial blood gas measurements,emergent spiral CT scans, chest tube insertions, or endotracheal intubation are not warranted. For this stable patient, continued monitoring with gradual withdrawal of oxygen is the most appropriate treatment.A 67-year-old woman with rheumatoid arthritis has had a 3-year history of gradually progressive right elbow pain and limited function despite intra-articular injections and medical management. She previously underwent a rheumatoid hand reconstruction, and has no pain or dysfunction of the ipsilateral shoulder.Radiographs are shown in Figures 93a and 93b. What is the most appropriate treatment?Soft-tissue interposition arthroplasty with radial head resectionArthroscopic synovectomy with radial head resectionElbow arthrodesisTotal elbow arthroplastyResection arthroplastyTotal elbow arthroplasty is the treatment of choice. The patient has end-stage rheumatoid involvement of the ulnohumeral and radiocapitellar joints. Given the advanced nature of the disease and evidence of bony erosion, arthroscopicsynovectomy and interposition arthroplasty are unlikely to provide lasting benefit or functional improvement. Elbow arthrodesis and resection arthroplasty are considered salvage techniques and are generally not considered as a primary treatment method.A 66-year-old woman with known poorly controlled rheumatoid arthritis reports that for the past 4 weeks she has been unable to extend the metacarpophalangeal (MCP) joints of her right hand index, middle, ring and little fingers. She cannot hyperextend the thumb interphalangeal joint. Active wrist extension is possible, but shows radial deviation. Examination reveals mild synovitis at the wrist and MCP joints of the affected hand. There is no ulnar deviation at the MCP joints with normal alignment. When the MCP joints are passively extended, the patient is unable to maintain them in this position.There is no piano key sign at the distal ulna. Passive wrist motion shows a normal tenodesis effect. Which of the following would most likely confirm your diagnosis?Radiographs of the handRadiographs of the cervical spineElectrodiagnostic studies of the affected upper extremitySurgical exploration of the extensor tendon rupturesMRI of the elbowThere are many causes of inability to extend the MCP joints in a patient with rheumatoid arthritis. The most common cause is rupture of the extensor tendons. An intact tenodesis test suggests that the extensor tendons are intact, thus surgical exploration is not indicated and would not confirm the diagnosis. The patient has normal alignment of the fingers without ulnar deviation, suggesting that there are no MCP dislocations to account for the inability to extend the MCP joints; therefore, radiographs would not confirm the diagnosis. The most likely cause of inability to extend the fingers in this patient is posterior interosseous nerve (PIN) palsy. Electrodiagnostic studies would confirm the presence of PIN palsy. An MRI of the elbow may show synovitis at the radiocapitellar joint, which can cause the PIN palsy. This finding however, is nonspecific and many patients without PIN palsy would also demonstrate synovitis at the radiocapitellar joint.Therefore, although an MRI would be helpful in localizing a potential cause of PIN compression, it would not in itself confirm the diagnosis.What is the predominant type of collagen found in the nucleus pulposus of the intervertebral disk?Type IType IIType VType VIType XIICorrent answer: 2Types I and II collagen are the predominant types of collagen found in the intervertebral disk. Type I collagen is present in the highest concentration in the annulus fibrosus and type II collagen in the nucleus pulposus. Type V collagen is present in small concentration in the annulus fibrosus. Type VI collagen is a non-fibrillar, short-helix collagen found in both the annulus and nucleus. Type XII is present in the annulus fibrosus only.What complication is associated with the use of epidural morphine and steroid paste after laminectomy?Surgical site infectionArachnoiditisUrinary retentionDisk space infectionsNerve irritationKramer and associates conducted a retrospective review during an "epidemic" period to identify the risk factors associated with a sudden increase in the rate of surgical site infections. They found in a multivariate analysis that the use of morphine nerve paste resulted in a 7.6-fold increase in postoperative surgical wound debridement, and an 11% rate of surgical site complications. There is no evidence in the literature verifying the incidence of postoperative urinary retention and arachnoiditis.Which of the following materials has the highest modulus of elasticity?Cortical boneCobalt-chromeCeramicTitaniumStainless steelYoung's modulus of elasticity is a measure of the stiffness of a material and its ability to resist deformation. This is the slope of the stress/strain curve in the elastic range. The highest modulus is ceramic, followed by: cobalt-chrome alloy, stainless steel, titanium, and then cortical bone.What medication has been shown to decrease osteolysis after total joint replacement surgery?BisphosphonatesNSAIDsTNF-alpha inhibitorsCalcium and vitamin D supplementationBMP-7Bisphosphonates have been shown to decrease osteolysis after total joint replacement surgery.Aseptic loosening and osteolysis are the primary causes of implant failure in total joint arthroplasty. Early findings indicate that bisphosphonates upregulate bone morphogenetic protein-2 production and stimulate new bone formation, leading to decreased osteolysis in total joint replacement surgery. Whilefurther investigation is required, bisphosphonates may play a future role in improving the long-term duration of joint arthroplasties.Shanabhag et al. reviewed the use of bisphosphonates and reported that they had the potential to enhance bone ingrowth into implant porosities, prevent bone resorption under adverse conditions, and dramatically extend the long- term durability of joint arthroplasties. They recommended further investigation into the subclasses to determine which ones are most beneficial.Arabmotlagh el al. performed a prospective study on use of alendronate after total hip arthroplasty. They reported that the alendronate-treated patients had significantly less periprosthetic bone loss on DXA scans after 6 years.Illustration A shows evidence of osteolysis (arrows) around a total hip arthroplasty.Incorrect Answers:5: These medication classes do not decrease osteolysis after total joint arthroplasty.A 60-year-old woman has progressive neck pain, upper extremity pain, and paresthesias. A lateral cervical spine radiograph and an MRI scan are shown in Figures 52a and 52b. What is the most likely underlying diagnosis?OsteomyelitisAnkylosing spondylitisAge-related degenerative changesRheumatoid arthritisPrevious cervical decompressionCorrent answer: 4The radiograph and sagittal T2-weighted MRI scan show multilevel degenerative changes and subaxial subluxations with anterolisthesis at C3-C4 and C4-C5 and retrolisthesis at C5-C6. In addition, there is evidence of midcervical kyphosis. Such findings are often seen in patients with rheumatoid arthritis. Patients with osteomyelitis typically show increased signal intensity in the disks and vertebral bodies. Patients with ankylosing spondylitis typically show ankylosis of the disks and vertebral bodies. Age-related degenerative changes typically manifest as degenerative disk disease with occasional single- level spondylolisthesis, but not typically multilevel spondylolisthesis, as seen in this patient. The spinous processes are intact; these changes do not appear to be postoperative.Which of the following actions increases radiation exposure to patients and personnel when using fluoroscopy?The use of lead glasses, thyroid shield, and a lead apron with a equivalent lead thickness of 0.25 mmOrienting the cathode ray tube beneath the patient with the image intensifier receptor as close to the patient as possibleLimiting the beam on time to only what is clinically importantThe use of continuous fluoroscopy to ensure proper placement of implantsOrienting the beam in the opposite direction of the working team and keeping the team outside a 6-foot radius from the fluoroscopy machineContinuous fluoroscopy and cineradiography exposes the patient and personnel to markedly increased levels of direct and scatter radiation exposure. Continuous fluoroscopy should be limited to only what is absolutely needed for safe completion of the procedure. By orienting the cathode raytube beneath the patient and placing the image intensifier as close as clinically possible to the patient, scatter radiation exposure to the personnel is minimized.Smoking has been associated with lower fusion rates in both cervical and lumbar fusion. Which of the following statements best describes an explanation for these findings?Nicotine impairs osteoblast activity, thus interfering with bone remodeling.The effects of smoking on bone healing are multifactorial and not yet fully understood.The vasoconstrictive and platelet-activating properties of nicotine inhibit fracture healing.Nicotine inhibits the function of fibroblasts, red blood cells, and macrophages.Hydrogen cyanide inhibits oxidative metabolism at the cellular level.Corrent answer: 2Tobacco smoking is now the leading avoidable cause of morbidity and mortality in the United States. The musculoskeletal effects of smoking have been implicated in osteoporosis, low back pain, degenerative disk disease, poor wound healing, and delayed fusion and fracture healing. A number of studies have demonstrated the relationship between smoking and development of pseudarthrosis. Numerous studies have been performed tooffer an explanation of the mechanism mediating this effect. Whereas all of the above have been postulated as explanations, more recent studies havedemonstrated that nicotine delivered via a transdermal patch significantly enhanced posterior spinal fusion in rabbits. Thus it appears that the effects of smoking on fracture healing are multifactorial and not yet fully understood.In which of the following scenarios should a physician be relieved of their duties?After 24 hours of continuous workA significant error in care is notedThe physician appears fatiguedPhysician is recovering from an ankle fractureChemical impairment is suspectedImpairment of a healthcare professional is the inability or impending inability to practice according to accepted standards as a result of substance use, abuse, or dependency (addiction). A surgeon (resident, fellow or attending) who discovers chemical impairment, dependence, or incompetence in a colleague or supervisor has the responsibility to ensure that the problem is identified and treated. Mechanisms exist for the proper identification and treatment of the impaired physician. Misconduct can be reported to state and local agencies. One must be sure to act in good faith with reasonable evidence when reporting such an incident. If a patient is at risk for immediate harm or injury by an impaired physician, one should assert authority and relieve the physician of the patient care and then address the problem with the senior hospital staff as soon as possible. The referenced article by Baldisseri is a review on the ethics of dealing with impaired healthcare professionals, with a focus on physicians.A 78-year-old woman has a history of chronic low back pain. She denies any extremity problems. Her pain is worse in the morning, and gets better, although it does not go away, as the day goes on. An MRI scan of the lumbar spine is shown in Figure 88. She denies any acute worsening of her symptoms, although in general, her symptoms are slowly worsening. She takes nonsteroidal anti-inflammatory drugs as needed for her pain, but otherwise takes no other medications. What is the next most appropriate step in management?DEXA scanBrace treatment with a Jewett hyperextension braceAnterior lumbar corpectomy and arthrodesis with instrumentationPosterior lumbar decompression and fusionVertebral cement augmentationThe patient has MRI findings throughout her lumbar spine consistent with old compression fractures. Given the imaging findings and advanced age, she is at high risk for osteoporosis and subsequent fragility fractures. Management should consist of a DEXA scan to evaluate her degree of osteoporosis andbegin medical treatment as appropriate. Because acute fracture is unlikely, and she has no neurologic compromise, neither bracing nor surgical treatment is indicated.Figure 10 is the radiograph of a middle-aged woman who has had midfoot pain for the past several years without antecedent trauma. What is the most likely etiology of her condition?OsteomyelitisKohler diseaseRheumatoid arthritisPrimary osteoarthritisOsteochondritis dissecansThe radiograph shows isolated degeneration in the talonavicular joint that is symmetric. The symmetry of the degeneration is characteristic of an inflammatory arthritis. In the absence of trauma, isolated arthritis in this joint is uncommon. The navicular is normal sized, ruling out Kohler disease (as well as the patient being in the wrong age group). There are no erosions indicative of osteomyelitis. Osteochondritis dissecans appears as focal osteochondral lesions, which are not present in the radiograph.Figure 39 is the radiograph of a 67-year-old woman with rheumatoid arthritis who reports an 8-month history of increasing pain, swelling, and deformity. Anti- inflammatory drugs, orthotics, and extra-depth shoes have failed to provide relief. What is the next most appropriate step in treatment?First metatarsophalangeal joint arthrodesis and lesser metatarsal head resectionsFirst metatarsophalangeal joint replacement and lesser metatarsal head resectionsKeller arthroplasty and lesser metatarsal head resectionsDistal Chevron osteotomy and lesser metatarsal head resectionLapidus procedure and Weil osteotomiesThe patient has a severe rheumatoid forefoot deformity involving all metatarsophalangeal joints. Coughlin and Mann have found that 90% of patients have excellent and good results with combined first metatarsophalangeal fusion and lesser metatarsal head resection. Keller arthroplasty does not provide a stable platform for walking and is associated with recurrent deformity and pain. The first metatarsophalangeal joint replacement has not been shown to provide reliable long- term results. Osteotomies may be indicated in patients without erosive joint changes. The Lapidus procedure is an arthrodesis of the first tarsometatarsal joint, which would not address the patient's arthritic first metatarsophalangeal joint.The operative report of a recent patient incorrectly documents the timing of peri-operative antibiotic administration. How should themedical record be legally altered?Obtain written approval from the hospital medical directorObtain written approval from the risk management teamObtain written approval from your lawyer and the senior partners of his law firmNo approval is needed, as you were the treating surgeon and have identifiedthe errorIt is illegal to alter the medical record, but an addendum can be madeIt is illegal to alter the medical record under any circumstance. If a documentation error has occurred, you may addend the medical record by identifying the error and noting the correction.The review article by Bal discusses medical practice and highlights the four legal elements that must be proven in litigation: (1) a professional duty owed to the patient; (2) breach of such duty; (3) injury caused by the breach; and (4) resulting damages.A 31-year-old woman underwent a left Kidner procedure 3 months ago. She now has pain overlying the medial column of the foot. She withdraws the foot when touching of the medial foot is attempted. Examination reveals allodynia, pain, hyperalgesia, and edema of the medial foot. What is the most likely diagnosis?ShinglesCellulitisCharcot footOsteomyelitisReflex sympathetic dystrophyPatients with reflex sympathetic dystrophy (RSD) have a history of trauma, minor rather than major (eg, Colles fracture), in about 50% to 65% of cases. The condition may also follow a surgical procedure. Patients usually have symptoms and signs of RSD including: pain, described as burning, throbbing, shooting, or aching; hyperalgesia; allodynia; and hyperpathia. There are trophic changes within 10 days of onset of RSD in 30% of the extremities affected, including stiffness and edema and atrophy of hair, nails, and/or skin.Finally there can be autonomic dysfunction, such as abnormal sweating, eitherin excess or anhydrosis, heat and cold insensitivity, or redness or bluish discoloration of the extremities. Shingles, also called herpes zoster or zoster, is a painful skin rash caused by the varicella zoster virus (VZV). VZV is the same virus that causes chickenpox. After a person recovers from chickenpox, the virus stays in the body.Usually the virus does not cause any problems; however, the virus can reappear years later, causing shingles. Charcot arthropathy is a progressive condition of the musculoskeletal system that is characterized by joint dislocations, pathologic fractures, and debilitating deformities. This disorder results in progressive destruction of bone and soft tissues at weight-bearing joints; in its most severe form, it may cause significant disruption of the bony architecture. In patients with diabetes, the incidence of acute Charcot arthropathy of the foot and ankle ranges from

DISCUSSION: MRI findings of acute osteomyelitis include a decrease in the normally high signal intensity of bone marrow on T1-weighted imaging; however, a postgadolinium T1-weighted image with fat suppression will show osteomyelitis as a bright marrow signal compared to the surrounding fat. Osteomyelitis is also brighter than normal fat on T2-weighted imaging. There is no rim-enhancing lesion suggesting an abscess, although myositis is seen in the obturator internus and short external rotators. The clinical scenario and imaging studies do not support the diagnosis of septic hip, eosinophilic granuloma, or pelvic fracture.

In long bones, radiographs initially show a radiolucency in the metaphysis that progresses into the diaphysis. The entire progression of the disease takes years.The radiograph here shows the typical Paget’s lesion in the right iliac wing with mixed lytic and sclerotic areas.