This practice set contains high-yield board review questions covering key concepts in 2. Trauma. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.
Question 10481
Topic: Upper Extremity Trauma
In the surgical treatment of a high-grade acromioclavicular (AC) joint separation, reconstruction of the coracoclavicular (CC) ligaments is planned. What is the normal anatomic orientation of the native conoid and trapezoid ligaments?
Correct Answer & Explanation
. Conoid is lateral and anterior; trapezoid is medial and posterior
Explanation
The coracoclavicular ligament complex consists of the conoid and trapezoid. The conoid is situated medial and posterior, while the trapezoid is lateral and anterior. Anatomic reconstruction aims to replicate these specific footprint locations.
Question 10482
Topic: 2. Trauma
During the surgical planning for a diaphyseal femur fracture, the surgeon selects a solid intramedullary nail. The torsional stiffness of a solid intramedullary nail is proportional to its radius raised to what power?
Correct Answer & Explanation
. 1st power
Explanation
The torsional stiffness of a solid cylinder is defined by its polar moment of inertia, which is proportional to the radius to the 4th power (r^4). Therefore, small increases in the radius of a nail dramatically increase its torsional rigidity.
Question 10483
Topic: 2. Trauma
During plate fixation of a fracture, a surgeon must maximize the pullout strength of the cortical screws placed into osteoporotic bone. The pullout strength of a bone screw is most significantly increased by an increase in which of the following screw parameters?
Correct Answer & Explanation
. Core diameter
Explanation
Screw pullout strength is primarily determined by the volume of bone caught between the threads. It is directly proportional to the outer (thread) diameter, the length of engagement in the bone, and the shear strength of the host bone.
Question 10484
Topic: 2. Trauma
A surgeon applies a locking compression plate (LCP) to bridge a comminuted diaphyseal fracture. Which of the following biomechanical principles best describes how a purely locked plate construct achieves stability?
Correct Answer & Explanation
. Relies strictly on frictional forces between the undersurface of the plate and the bone
Explanation
Locking plates function as internal fixators. The threaded screw heads lock into the threaded plate holes to create a rigid, fixed-angle construct that does not rely on friction between the plate and bone, eliminating the need for precise contouring.
Question 10485
Topic: 2. Trauma
A surgeon is repairing a highly comminuted midshaft humerus fracture in an osteoporotic patient and wishes to maximize the pullout strength of the cortical screws. Which of the following screw modifications will most significantly increase screw pullout strength in this osteoporotic bone?
Correct Answer & Explanation
. Decreasing the major (outer) diameter
Explanation
Pullout strength is directly proportional to the outer diameter and the volume of bone caught between the threads. Decreasing the pitch increases the number of threads per unit length (thread density), thereby capturing more bone and significantly increasing pullout strength.
Question 10486
Topic: 2. Trauma
In a randomized controlled trial comparing two fracture fixation devices, the authors report no statistically significant difference in nonunion rates (p = 0.15). However, a true difference in efficacy exists between the devices in the general population. This study result is an example of:
Correct Answer & Explanation
. Type I error
Explanation
A Type II error (beta) occurs when a study fails to reject a false null hypothesis, meaning it misses a true difference. This is often caused by an inadequate sample size and resulting low statistical power.
Question 10487
Topic: Lower Extremity Trauma
An orthopedic manufacturer creates two solid circular intramedullary nails. If the radius of the second nail is increased by 10% compared to the first, approximately how much does its bending rigidity increase?
Correct Answer & Explanation
. 10%
Explanation
The bending rigidity (area moment of inertia) of a solid cylinder is proportional to the radius to the fourth power (r^4). Increasing the radius by 10% (1.1x) increases the rigidity by 1.1^4 = 1.4641, representing a roughly 46% increase.
Question 10488
Topic: 2. Trauma
A 45-year-old male undergoes a hip resurfacing arthroplasty. Six months later, he sustains a fracture of the femoral neck. Which of the following surgical factors most significantly increases the risk of this specific complication?
Correct Answer & Explanation
. Valgus positioning of the femoral component
Explanation
Varus positioning of the femoral component in hip resurfacing shifts the load laterally, increasing tensile forces on the superior femoral neck. This significantly increases the risk of a post-operative femoral neck fracture.
Question 10489
Topic: 2. Trauma
A 55-year-old male sustained the injury in Figure A. His injury was complicated by an acute compartment syndrome. He underwent external fixation of his extremity and four compartment fasciotomy. When should the treatment shown in Figure B be performed to minimize the risk of infection?
Correct Answer & Explanation
. Before fasciotomy closure
Explanation
The timing of definitive fixation of tibial plateau fractures in patients with fasciotomies has no impact on infection risk.The incidence of compartment syndrome is high in tibial plateau fractures. In the presence of tense anterior and lateral tibial compartments, combined with pain with passive stretch of involved muscles or unrelenting pain, compartment pressures should be measured and fasciotomies performed when necessary.Schatzker type V and VI fractures are more likely to have this potential complication. Examination of leg compartments should be repeated at regular intervals because compartment syndrome may occur 24 hours or more after injury.Zura et al. performed a study to analyze whether there is an association between infection and the timing of definitive fracture fixation in relation to fasciotomy closure or coverage. They found that no statistical difference in the rate of infection when tibial plateau fractures with four-compartment fasciotomies were treated with open reduction and internal fixation before fasciotomy closure, at fasciotomy closure, or after fasciotomy closure. They conclude that timing of definitive fracture treatment can be determined by the medical condition of the patient.Shah et al. performed a retrospective chart review of all bicondylar tibial plateau fractures that had fixation with two incisions. They reported an infection rate of 13.8% which is lower than historical reports. They concluded that the lower infection rate was due to their treatment algorithm that requires recovery of the soft tissue envelope prior to definitive fixation.Figure A demonstrates a bicondylar tibial plateau fracture. Figure B demonstrates fixation of a tibial plateau fracture through a dual plating technique.Incorrect Answers:Answers 1, 2, 3, and 4 are incorrect as infection risk is unchanged with timing of definitive fracture fixation.
Question 10490
Topic: 2. Trauma
A 37-year-old male sustained the injury shown in figure A. He was treated with an intramedurally nail and a post-operative radiograph is shown in figure B. He underwent a post-operative CT Scanogram to assess for rotation. Figures C and D are of the operative side and Figures E and F are of the uninjured side. What is the version of the injured side and should any further procedures be undertaken for correction?
Correct Answer & Explanation
. Femoral anteversion of 36 degrees, no further procedures required
Explanation
This patient has neutral version on the operative side and 6 degrees of anteversion on the normal side, therefore no further procedures are required.Rotational malalignment or torsional deformity is expressed as a difference in femoral version between the injured and uninjured leg. It can be measured clinically, radiograpically, and most accurately by CT scan. CT scan is the method of choice because of its reliability and reproducibility. The incidence of rotational malalignment may be as high 30% in some fracture patterns.Fracture comminution is a risk for rotational malalignment as it alters the ability to obtain a cortical read. Differences between sides of <10 degrees are considered variations of normal while differences of >15 degrees are considered true torsional deformities and likely require de-rotation.Jaarsma et al. detail how to obtain a rotational profile of the femur. Rotational alignment is determined by the angle between a line tangential to the femoral condyles and a line drawn through the axis of the femoral neck. The difference in angle between the fractured and unaffected side determines the rotational alignment. A decrease in anteversion of the femoral neck of the fractured side implies increased external rotation and an increase denotes increased internal rotation of the distal fragment.Koerner et al. measured 328 normal femora and found that there were no statistically significant differences in mean version between African American, white, and Hispanic patients for males or females. They found retroversion to be common in white males, African American males, and all females. They conclude that this may have implications in proper alignment restoration after IM nailing of femur fractures.Gardner et al. performed a cadeveric study and found that freehand distal interlocking may be a substantial cause of rotational deformity. They found that freehand insertion may cause a 7 degree change in alignment. They saw that when inserting the drill freehand, drill/nail contact caused a visible shift of the fracture site. They conclude that the use of computer navigation systems may improve this issue.Figure A demonstrates a subtrochanteric femur fracture, while Figure B demonstrates the same fracture, stabilized with a piriformis entry nail. Figures C-F demonstrate axial CT cuts to determine femoral version. Figure C demonstrates hip anteversion of 18 degrees, while figure D reveals knee external rotation of 18 degrees. This side exhibits neutral rotation (18-18).Figure E demonstrates hip anteversion of 9.2 degrees while figure F demonstrates knee external rotation of 3.2 degrees. This side exhibits 6 degrees of anteversion (9.2-3.2).Incorrect Answers:Answers 1, 2, 4, 5 do not have the correct combination of version and need for further procedures.
Question 10491
Topic: 2. Trauma
A 33-year-old male suffers a gunshot to the right forearm as seen in figure A. There is a 2 cm radial-sided wound with exposed bone. What is the most appropriate treatment?
Correct Answer & Explanation
. Irrigation and debridement with open reduction and internal fixation of the radius and ulna with 3.5-mm LC-DCP bridge plate
Explanation
The patient has a comminuted, relatively high-energy open fracture of the right radius and ulna, which is best treated with irrigation and debridement of the gunshot wounds followed by early internal fixation if possible using a 3.5 mm LC-DCP plate placed with a bridging technique.Diaphyseal forearm fractures are best treated with open reduction and internal fixation to restore anatomic alignment and absolute stability. Typically this is achieved by the use of 3.5 mm plates, placed in such a manner to produce interfragmentary compression. Due to the comminution in this case, bridge plating will provide a superior outcome as it will minimize interfragmentary strain and preserve the local bone biology. Multiple studies have demonstrated that open reduction and internal fixation at the initial encounter is appropriate, even if there is comminution, bone loss, or an open injury requiring multiple debridements.Anderson et al. performed a retrospective study of 87 patients with 129 diaphyseal forearm fractures treated with dynamic compression plates. Open fractures were fixed primarily and the overall union rate was 98%. Refracture occurred in 2 patients after removal of 4.5 mm plates, whereas there were no refractures after removal of the 3.5 mm plates.Moed et al. reviewed 57 patients that underwent immediate internal fixation of a diaphyseal forearm fracture. Functional results were good to excellent in 85% of patients and there were 2 deep infections and 6 non-unions overall.The authors conclude immediate plate fixation is an appropriate treatment method for open diaphyseal forearm fractures and recommend autogenous grafting at the time of wound closure.Jones et al. analyzed a retrospective case series of 18 patients with grade 3 open diaphyseal forearm fractures treated with irrigation and debridement and immediate open reduction and internal fixation followed by aggressive soft tissue management over the following weeks. Their treatment protocol provided good to excellent results in 66% of patients, indicating immediate reduction and fixation may be an acceptable treatment for some patients.Figure A demonstrates comminuted radius and ulna shaft fractures with retained bullet fragments.Incorrect answers:Answer 2: The patient has an open fracture which requires urgent debridement Answer 3: Compression plating will not work for this comminuted fracture pattern.Answer 4: While bridge plating is appropriate, 4.5mm plates are too large and have an increased risk of refracture if later removal is requiredAnswer 5: External fixation is not necessary, this fracture can be treated with immediate open reduction and internal fixation.
Question 10492
Topic: 2. Trauma
A 29-year-old obese patient is transferred from an outside facility for the management of a closed-head injury and the fracture shown in Figure A. He presents to the trauma bay as a transient responder to blood products, and undergoes urgent pre-surgical angiography embolization. Surgery is performed within 8 hours from the time of injury. The patient develops a deep wound infection 1 week post-operatively. Which of the following factors would be considered the MOST statistically significant predictor for post-operative infection in this patient.
Correct Answer & Explanation
. Head injury
Explanation
From the following options, only obesity has been shown to be associated with a statistically higher incidence of wound complications following pelvic and acetabular fracture fixation for trauma.Wound complications following pelvic and acetabular fracture fixation is relatively uncommon. Literature suggests and prevalence of 2-8% with closed fracture injuries. Factors shown to increase infection rates include both patient and surgical factors. They include obesity, diabetes, immunocompromised, elderly, pre-operative embolization and open fractures.Sagi et al. looked at the factors contributing to wound infection after pelvic and acetabular surgery. Open pelvic or acetabular fractures were excluded. Of all the factors, only obesity (OR 8, PPV 33%), obesity plus leukocytosis (OR 12, PPV 39%), and preoperative angioembolization (OR 11, PPV 67%) were strong predictors of postoperative infection.Manson et al. aimed to determine if embolization of pelvic arterial injuries before open reduction and internal fixation (ORIF) of acetabular fractures is associated with an increased rate of deep surgical site infection. They retrospective reviewed 1440 patients who underwent ORIF of acetabular fractures. They found a 58% infection rate of the patients who underwent embolization before ORIF vs, historical controls (2%-5%) and angiography without embolization (14%).Figure A shows an AP radiograph and 3D CT reconstruction of a APC3 pelvic ring fracture.Incorrect Answers:Answer 1: Head injury has not been shown to increase infection rates. It has been shown to increase heterotrophic ossification.Answer 3: Gender has not shown to increase infection ratesAnswer 4: Early surgery has not been shown to affect infection rates. Answer 5: Transfer from an outside facility has not been shown to affect infection rates.
Question 10493
Topic: 2. Trauma
A 40-year-old man sustains a fall while mountain biking and presents with a posterior elbow fracture-dislocation. The elbow is reduced in the ER and noted to be grossly unstable with varus and valgus stress. Imaging demonstrates a two part radial head fracture involving 40% of the articular surface and a fracture involving less than 10% of the coronoid tip. He is taken to the OR for surgical reconstruction. After fixation of the radial head and repair of the LCL complex, the elbow is fluoroscopically examined and noted to be unstable with valgus stress. The elbow is ranged and dislocates at less than 45 degrees of flexion with the forearm in full supination. What is the next best step in management?
Correct Answer & Explanation
. Repair of the medial collateral ligament
Explanation
This patient has persistent elbow instability likely secondary to medial collateral ligament (MCL) rupture and therefore should undergo repair of the MCL, followed by repeat fluoroscopic examination. Small coronoid fractures involving less than or equal to 10% of the coronoid tip do not confer major elbow instability and do not necessitate repair. Terrible triad injuries of the elbow are characterized by: 1. Radial head fracture, 2. Coronoid fracture, and 3. Elbow dislocation. Whether to surgically address the coronoid fracture depends on the size of the fragment as well as elbow stability. Gross elbow instability in the presence of a type I fracture is most likely due to an independent MCL injury and NOT the coronoid avulsion.
Question 10494
Topic: 2. Trauma
A 40-year-old man fell off of a ladder at work sustaining the injury shown in Figures A and B. On examination, his skin is intact, but the pulses in his foot are absent. Following closed reduction and splinting, what would be the next best step?
Correct Answer & Explanation
. Re-evaluate pulses
Explanation
This patient sustained a posterior ankle fracture/dislocation. After closed reduction and splinting, the next best step should be to re-evaluate pulses.With any dislocation, an immediate closed reduction should be performed. Though the initial vascular examination was abnormal in this case, the dislocation is contributing to this finding. This unique ankle fracture is known as the hyperplantarflexion variant. It is composed of a posterior tibial lip fracture with posterolateral and posteromedial fracture fragments separated by a vertical fracture line.Gardner et al. review the hyperplantarflexion variant and found that the fracture of the posteromedial tibial rim was the main feature of this injury which is sustained by a hyperflexion mechanism. They also reported that posterior malleolus fractures are present in a majority of these injuries as well.On MRI they determined that the deltoid and posterior tibiofibular ligaments were intact in all cases. They conclude, when treating these fractures with ORIF of the posteromedial and posterior fragments with antiglide fixation, excellent results were obtained.Hinds et al. name the unique double cortical density at the inferomedial tibial metaphysis the "spur sign." They found the spur sign to be present in 79% of variant ankle fracture cases. They found the positive predictive value and negative predictive value to be 100% and 99%, respectively when this sign is present.Figures A and B demonstrate the hyperplantarflexion variant ankle fracture. Illustration A demonstrates the spur sign, as indicated by the red arrow.Incorrect Answers:Answer 2: Vascular consultation may be obtained if the vascular exam is abnormal.Answer 3: CT angiography may be obtained after closed reduction to aid in the diagnosis of vascular injury if the exam is abnormal after closed reduction.Answer 4: A formal angiogram may be necessary if there is an abnormality in the vascular exam.Answer 5: Surgical exploration and stabilization may eventually be necessary, but are not the next best step in treatment.
Question 10495
Topic: 2. Trauma
A young male patient underwent intramedullary nail fixation for a diaphyseal femur fracture. A post-operative CT scanogram is performed to assess rotational alignment between the surgical and non-surgical femur. Which of the following measurement(s) are considered acceptable differences in regards to femoral rotational
malreduction after intramedullary nail fixation as compared to the uninjured femur?
Correct Answer & Explanation
. 9 degrees internal rotation
Explanation
The maximum acceptable difference in rotational malreduction between the surgical and contralateral legs for femoral version is 15°. Therefore, answers 1 and 2 are correct.Normal femoral neck anteversion is approximately 11-13°, with a normal range between 5-20°. The variation within the same patients can also be up to 15° difference between limbs. Current literature has shown that this 15° difference is well tolerated by patients, including when this has occured as a result of rotational malreduction following intramedullary nail fixation for a diaphyseal femur fracture.Ayalon et al. aimed to compare the difference in femoral version (DFV) after intramedullary nailing performed by a trauma-trained and non-trauma trained surgeon. The mean post-operative DFV was 8.7° in these patients, compared to 10.7° in those treated by surgeons of other subspecialties. Post-operative version or percentage of DFV >15° did not significantly differ between these two groups.Omar et al. studied the utility of pre-operative 'virtual reduction' of bilateral femoral fractures that were initially stabilized with external fixation. After external fixation, the mean rotational difference between both legs was 15.0°± 10.2°. Following virtual reduction, the mean rotational difference between both legs was 2.1° ± 1.2°, after intramedullary nailing, compared to 6.1° ±2.8° without the pre-operative tool.Illustration A shows the typical CT scanogram cuts used to measure femoral version. Note, femoral version is obtained by measuring an angle between a line along the femoral neck and another line along the posterior condylar axis.Incorrect Answers:Answers 1-5: More than 15° difference in version between femurs is considered the upper limit for acceptable reduction.
Question 10496
Topic: 2. Trauma
A 20-year old male was involved in a motor vehicle accident. He is complaining of bilateral leg pain. He has a mean arterial pressure of 80, heart rate of 90, a lactate level of 1.2 mmol/L, and base deficit of
0.5. On physical examination, he has no open wounds and is neurologically intact in both lower extremities. Imaging of the right femur (Figures A and B) and the left femur (Figures C and D) is shown. What is the next best step in treatment?
Correct Answer & Explanation
. Skeletal traction and observation until the patient is better resuscitated
Explanation
Figures A-D are radiographs demonstrating bilateral femur fractures in an adequately resuscitated patient. This injury pattern is best treated with bilateral, reamed, retrograde femoral nails.This patient has been adequately resuscitated and should undergo definitive stabilization of his injuries. Indicators for adequate resuscitation are mean arterial pressure > 60, heart rate <100, urine output of 30 cc/hour, serum lactate of < 2.5, gastric mucosal pH > 7.3, and a base deficit of -2 to +2.Bilateral femoral shaft fractures are a relative indication for retrograde femoral nailing. When compared to antegrade nailing of this injury pattern, retrograde nailing has a decreased operative time because the extremities may be prepped and draped together, eliminating the need to re-position and re-prep the patient.Nork et al. performed a review of patients treated with reamed intramedullary nailing of a femoral shaft fracture. They found 54 patients with bilateral femoral shaft fractures. They report that mortality in these patients was 5.6% compared to 1.5% in the unilateral group. Bilateral fractures are also associated with a longer length of stay in the hospital and a longer length of stay in the intensive care unit. They conclude that patients with bilateral fractures sustain a higher injury burden than patients with unilateral injuries.Pape et al. performed a study to determine whether the use of a reamer that provides simultaneous irrigation and aspiration of intramedullary contents can lower the risk of pulmonary embolization when performing a femoral nail. The experiment was performed in sheep treated with femoral nails separated into 3 groups: reamed femoral nailing, reaming with irrigation and aspiration, and unreamed nailing. They conclude that in the presence of unilateral pulmonary injury, the effects of reaming may be minimized by irrigating and aspirating the canal.Brumback et al. wrote a review on intramedullary nailing of the femur comparing reamed and unreamed techniques. They report that reamed intramedullary nailing has not been associated increases in pulmonary complications while unreamed nailing has been shown to have slightly higher rates of delayed union and nonunion. They conclude that reamed interlocking intramedullary fixation remains the treatment of choice for femoral shaft fractures in adults.Figures A-D are radiographs demonstrating a femoral shaft fracture. Incorrect Answers:Answers 1 & 2: This patient is adequately resuscitated and definitive fixationmay be performed.Answer 3: Though plate and screw fixation may be used in the treatment of femoral shaft fractures, intramedullary nailing is the preferred treatment.Answer 4: Unreamed nailing should not be performed in adults.
Question 10497
Topic: 2. Trauma
Which of the following pelvic injury types has the highest reported mortality rate?
Correct Answer & Explanation
. Anterior posterior compression (APC) III injury
Explanation
Anterior posterior compression (APC) injuries have the highest mortality rates of the fracture patterns listed. APC injuries have high rates of concomitant thoracic and abdominal visceral injuries leading to the highest rates of mortality among pelvic fractures. The overall mortality rate for any pelvic trauma is roughly 15%, with APC III mortality around 37%, and overall APC mortality rates around 26%.
Question 10498
Topic: 2. Trauma
Which of the following is an indication for surgical treatment of an acute humeral shaft fracture?
Correct Answer & Explanation
. radial nerve palsy
Explanation
Humeral shaft fractures can be managed nonoperatively due to a high union rate with infrequent complications. Certain situations, however, favor operative osteosynthesis: failure of closed reduction, associated articular injury, vascular or brachial plexus injuries, associated ipsilateral forearm fractures, segmental fractures, and pathologic fractures. Open fractures should be irrigated and debrided if necessary with subsequent external or internal fixation. Polytrauma patients with multiple extremity or multi-system injuries may also be considered for operative stabilization. A relative indication also may be the transverse or short oblique fracture in an active patient since these fracture patterns are more prone to delayed union. An acute radial nerve palsy associated with a humeral shaft fracture is not an indication for surgery.
Question 10499
Topic: 2. Trauma
A 32-year-old male sustains a closed head injury, a closed pelvic ring injury, as well as the bilateral open femoral fractures shown in Figures A-C. He remains borderline hypotensive with a base deficit of
4.9 after an exploratory laparatomy and splenectomy. After irrigation and debridement of his open fractures, what is the most appropriate treatment for this patient at this time?
Correct Answer & Explanation
. Bilateral retrograde femoral nailing and pelvic binder application
Explanation
Figure A shows a complex pelvic ring injury, while Figures B and C show bilateral femur fractures. Appropriate treatment of an unstable, head-injured patient with the above injuries includes prompt, judicious external fixation of his bilateral femoral fractures and pelvic ring injury. The advantages of early fracture fixation in patients with multiple injuries have been challenged recently, particularly in patients with head injury. External fixation (EF) has been used to stabilize pelvic fractures after multiple injury. It potentially offers similar benefits to intramedullary nail (IMN) in long-bone fractures and may obviate some of the risks. EF is a viable alternative to attain temporary rigid stabilization in patients with multiple injuries. It is rapid, causes negligible blood loss, and can be followed safely by IMN when the patient is stabilized.The referenced article by Scalea et al found that external fixation for femur fractures is a viable alternative to attain temporary rigid stabilization in patients with multiple injuries.
Question 10500
Topic: 2. Trauma
A 25-year-old male is a driver in a motor vehicle accident and sustains the isolated closed injury seen in Figures A and B. He is treated with an intramedullary nail, and postoperative radiographs are shown in Figures C and D. Which of the statements concerning reaming and nails is true?
Correct Answer & Explanation
. Unreamed tibias have the highest amount of mineral apposition rates
Explanation
The patient in the scenario has a closed distal one-third tibia fracture. Canal reaming increases the biologic environment for fracture healing but can potentially disrupt cortical blood flow. As such, many recommend canal reaming 1-2mm greater than the canal width followed by insertion of a nail that matches the native canal width. Reamed and unreamed tibias have similar mineral apposition rates.In 1998, Hupel et al studied the effect of loose and tight unreamed, locked nails on cortical blood flow and strength of union in a canine model. They found that loose nails allowed higher cortical reperfusion at the time of insertion and at eleven weeks.In a later study by the same group in 2001, they studied the effect of non-reamed, limited reamed and standard reamed nails on porosity, new bone formation and mineral apposition. They found the lowest porosity in the limited reaming group but found new bone formation and mineral apposition rates similar at eleven weeks across the three groups. They concluded that limited reaming is preferred in patients with vascular compromise to the tibia.Incorrect Answers:1: Reamed and unreamed tibias have similar mineral apposition rates. 2: Reamed tibias have the highest amount of new bone formation.3: The lowest porosity of bone is seen with limited reaming.5: Nails that are tight to the cortex have less reperfusion than appropriately fitting or loose nails.
Test Yourself
Switch to an interactive, timed exam simulation to truly master this topic.