2. Trauma MCQs

DISCUSSION: Illustration A found below depicts the method to calculate Tip-apex distance (TAD). The tip-apex distance is the sum of the distances from the tip of the lag screw to the apex of the femoral head as seen on the AP and lateral radiographs. Baumgaertner et al reported that he had no screws cut out if the tip-apex distance was less than 25mm. Tip-apex distance was the strongest predictor of cutout. Increasing age of the patient, poor reduction, use of a high angle sideplate, and unstable fracture were weaker predictors of cutout. Kyle et al demonstrated that obtaining an anatomic reduction when using a sliding hip screw with intertrochanteric fractures leads to the best radiographic and clinical outcomes.

According to Haidukewych and associates, treatment of reverse obliquity trochanteric femoral fractures with 95-degree fixed angle plates or with cephalomedullary intramedullary nails provides results superior to sliding hip screw devices. Moroni and associates demonstrated that external fixation with hydroxyapatite-coated pins provides satisfactory results for complex trochanteric fractures. Hip arthroplasty is not indicated for reverse obliquity fractures because this procedure still requires healing of the greater trochanteric fracture fragment to the shaft.

OrthoCash 2020Lateral malleolus fractures can be treated with a variety of techniques, including posterior antiglide plating or lateral neutralization plating. What is an advantage of using lateral neutralization plating instead of posterior antiglide plating?Decreased joint penetration of distal screwsIncreased rigidityDecreased need for delayed hardware removalDecreased peroneal irritationImproved distal fixationCorrent answer: 4Posterior antiglide plating is a technique that involves placement of a plate on the posterior aspect of the distal fibula, using the plate as a reduction tool and direct buttress against distal fracture fragment displacement.Schaffer et al showed from a biomechanical standpoint that posterior antiglide plating was superior to lateral neutralization plating for distal fibula fracture fixation.Weber et al reported a (30/70) 43% rate of plate removal secondary to peroneal discomfort. In addition, peroneal tendon lesions were found in 9 of the 30 patients.OrthoCash 2020A 24-year-old female sustains a surgical neck proximal humerus fracture in a motor-vehicle collision. She undergoes open reduction and internal fixation but heals in 45 degrees of varus and has significant limitation of shoulder range of motion despite 9 months of conservative treatments. What is the most appropriate treatment at this time?Manipulation under anesthesiaHumeral head resurfacingShoulder hemiarthroplastyRevision open reduction internal fixation with osteotomyReverse total shoulder arthroplastyCorrent answer: 4Malunions of the proximal humerus typically result in significant restrictions in range of motion. This young patient has sustained a proximal humeral malunion, and treatment should include a corrective osteotomy for improved outcomes, as she has failed conservative treatment.The cited reference by Williams et al as well as the referenced article by Siegel et al explain various techniques in management of proximal humerus malunions. They state that the two primary indications for surgical management of proximal humerus malunion include 1) pain and 2) diminished function resulting from limited range of motion. Because this patient is young, you would attempt revision ORIF/osteotomy as opposed to humeral head arthroplasty.OrthoCash 2020A 6-year-old boy with progressive bilateral genu varum undergoes the surgeries shown in Figure A. On postoperative rounds later that day, the patient appears sedated after several doses of pain medication. His toes are pink with brisk capillary refill however, passive motion of his toes causes pain. Among the answer choices listed, what is the best management strategy for this child?Elevate his legs and reevaluate on morning roundsAdjust his pain medication to accommodate for his increasing painAdminister a muscle relaxant for leg spasmsCast removal and measurement of compartment pressures with a standard deviceExamine the cast for areas of constriction and reevaluate in the morningCorrent answer: 4Intracompartmental pressure measurements should be performed when pain with passive motion of the toes is found in young patients with insufficient clinical data to establish a definitive diagnosis of compartment syndrome. The child in this clinical vignette has Blount’s disease which was treated with bilateral tibial osteotomies, a procedure commonly associated with compartment syndrome.Pain with passive stretch is the most sensitive clinical sign of elevated compartment pressures prior to the onset of ischemia in compartment syndrome. Pain is difficult to assess in children at baseline, therefore, a high level of suspicion should exist and compartment pressure monitoring should be performed in unreliable patients.Mubarak et al. reported on a series of 27 patients subjected to intracompartmental pressure monitoring for a clinical suspicion of acute compartment syndrome. The wick catheter technique was employed not only to aid in the diagnosis of compartment syndrome at an early stage but also to indicate the effectiveness of the decompressions when used intraoperatively during fasciotomies.Matsen et al. reported on 24 children with compartment syndrome following injuries and surgery. The most common etiologies identified were fractures, vascular injuries, and tibial osteotomies. Compartment pressure measurements were helpful in establishing the diagnosis of compartment syndrome in young patients and in those with neurologic or vascular injuries with ambiguous clinical findings.Figure A reveals an AP radiograph of bilateral knees status post valgus-producing tibial osteotomies and epiphysiolyses of the medial tibial physes in a 6-year-old male with Blount’s disease.Incorrect Answers:OrthoCash 2020A 16-year-old male was struck by an automobile while riding his bicycle. He sustained the injuries in Figure A. Which of the following orthopedic injuries is MOST associated with this injury?Brachial plexus injuryIpsilateral clavicle fracturePelvic ring injuryRib fractureSpine fractureFigure A demonstrates a scapula body fracture. Rib fractures are the most common orthopedic injury associated with these high-energy fractures, with a 52% incidence.Scapula fractures are associated with high-energy trauma and have a reported mortality rate of 2-5%. Approximately 50% of high-energy scapular fractures involve the body and spine. Most scapular fractures may be treated conservatively with sling immobilization followed by early motion with no expected functional deficits. Indications for operative management of scapular fractures include glenohumeral instability with >25% of glenoid involvement or>5mm of articular step-off, excessive medialization of the glenoid, displaced scapular neck or coracoid fractures, and open fractures.Baldwin et al. retrospectively reviewed 9,543 scapular fractures utilizing the US National Trauma Database. They reported that the most commonly associated fractures were rib fractures (52.9%), followed by fractures of the spine (29.2%), clavicle (25.2%), and pelvis (15.3%). They concluded that lung and head injuries occurred in 47.1% and 39.1% of the cases, respectively.Brown et al. retrospectively reviewed the association between scapular fractures (SF) and blunt thoracic aortic injury (BTAI). They found that in 35,541 blunt trauma admissions, SF and BTAI occurred in 1.1% and 0.6% of patients, respectively. They noted that most of the patients with SF had associated injuries (99%), but only four patients with SF had BTAI. The most common injuries associated with SF were rib (43%), lower extremity (36%), and upper extremity (33%) fractures. They concluded that SF is uncommon after blunt trauma, but patients with SF almost always have significant associated injuries and indicates a high amount of energy.Figure A demonstrates a high-energy scapular body fracture which may benefit from surgical interventionIncorrect Answers:OrthoCash 2020Which of the following amputations will lead to the greatest oxygen requirement per meter walked following prosthesis fitting?Above-knee-amputation (transfemoral)Below-knee-amputation (transtibial)Through KneeSymeMidfootThe general trend is increasing energy requirement for more proximal amputations. Amputation should be performed at the lowest possible level in order to preserve the most function.Pinzur compared 5 patients with amputations at midfoot, Syme’s, BKA, through knee, and AKA with five controls. Walking speed and cadence decreased while oxygen consumption per meter walked increased with each more proximal amputation.The only exception is the Syme which was the most energy efficient even though it is more proximal to the midfoot amputation.OrthoCash 2020An otherwise healthy 30-year-old male sustains a left forearm injury as a result of a fall from a ladder. Initial examination in the emergency room reveals a clean 2 centimeter laceration over the volar forearm associated with the radiographs shown in Figures A and B. Treatment should consist of irrigation and debridement of the wound followed by which of the following?Closed reduction and casting of left radius and ulnaTemporary external fixation of the left radius and ulnaDefinitive external fixation of the left radius and ulnaOpen reduction and internal fixation of the left radius and ulna with delayed skin closureOpen reduction and internal fixation of the left radius and ulna with immediate skin closureThe clinical scenario is consistent with an open fractures of the distal radial and ulnar shafts. Literature shows that definitive plating of an open forearm fracture followed by primary closure of the wound is acceptable treatment at the time of injury.Chapman et al performed a retrospective review of 50 patients with immediate internal plate fixation of an open diaphyseal fracture of the forearm. The functional results were excellent or good in 85%.The review by Levin is a comprehensive review of the literature on early versus delayed closure of open fractures, and covers the change in thought from previous literature, including change in technology, surgical techniques, and a more critical review of previous literature.OrthoCash 2020During a Lisfranc (tarsometatarsal) amputation of the foot, which of the following is crucial to prevent the patient from having a supinated foot during gait.Releasing the posterior tibialis tendonPreserving the soft-tissue envelope (peroneus brevis, tertius and plantar fascia) around the fifth metatarsal baseMyodesis of the anterior tibialis to the medial and middle cuneiformsLengthening of the gastrocsoleus (achilles tendon)Osteotomy through 1st metatarsalCorrent answer: 2A Lisfranc amputation is through the tarsometatarsal joints, except the 2nd metatarsal, which is osteotomized to preserve the stability of the medial cuneiform. To prevent the patient from supinating the foot following this amputation, the evertors on the foot must be maintained. The principal evertors are the peroneus brevis and longus (Illustration A). Therefore, the function of the peroneus brevis must be preserved. Technically this is done preserving the soft-tissue envelope (peroneus brevis, tertius and plantar fascia) around the fifth metatarsal base.Illustration B depicts the level of a Lisfranc amputation of the foot. Incorrect Answers:The posterior tibialis is the primary supinator of the foot, and releasing itwould lead to an eversion deformity. The tibialis posterior tendon attachment to the bases of the second and third metatarsals will actually be released with this amputation, but the main attachment to the navicular preserved.The anterior tibialis dorsiflexes and inverts the foot, but transferring it to the medial and middle cuneiforms would mimick its native function to dorsiflex and invert the foot.A lengthened Achilles would lead to increased dorsiflexion, not supination.Osteotomy of 2nd MT is crucial to preserve the medial cuneiform and midfoot stable.OrthoCash 2020A 39-year-old male is thrown from his motorcycle into a fast-food restaurant and sustains a closed pelvic ring injury. During placement of percutaneous iliosacral screws, the outlet radiograph in Figure A is obtained. What purpose does this view serve?Evaluation of possible injury to L5 nerve rootEvaluation of anterior-posterior position of screw(s)Best visualization of sagittal curvature of sacral alaBest visualization of spinal canalBest visualization of sacral neural foraminaCorrent answer: 5Figure A shows an intraoperative outlet view, which provides the best visualization of the neural foramina (and possible screw placement into these foramina). This view provides information regarding cephalad-caudad placement of the screw, whereas the inlet view provides information regarding the anterior-posterior position of the screw. The lateral sacral view provides information regarding the sagittal curvature of the sacral ala and gives information regarding possible iatrogenic L5 nerve injury as it goes over the sacral ala.The referenced article by Routt et al is a review article regarding the safety and techniques of percutaneous pelvic ring fixation.OrthoCash 2020A 35-year-old male sustains a closed Schatzker VI tibial plateau fracture. Two weeks following external fixation, examination reveals intact sensation, palpable pulses and no soft tissue compromise. An axial CT image is shown in Figure A. What is the optimal surgical plan?Medial and lateral plate fixation through two approachesMedial and lateral plate fixation through a single anterior approachLateral locking plate fixationContinued external fixation until unionMultiplanar transarticular external fixatorCorrent answer: 1The Figure shows a bicondylar tibial plateau fracture. The goals that need to be met when treating tibial plateau fractures are the following: restoration of mechanical axis alignment, restoration of condylar width, articular reduction, and restoration of knee stability. Since the soft tissue envelope is favorable, open reduction internal fixation with dual incisions and dual plates will provide the best probablity of achieving those goals.Gosling et al did a biomechanical evaluation in cadavers comparing lateral locked plating with a combined medial and lateral plate and found no difference in resistance to vertical subsidence even with loads exceeding the average body weight. However, this was a cadaveric study with no mention and capability of analyzing articular reduction. Lateral locked plating only allows for indirect reduction of the medial plateau.Barei et al in a retrospective review found that comminuted bicondylar tibial plateau fractures can be successfully treated with open reduction and medial and lateral plate fixation using 2 incisions, and postulate that the use of 2 incisions may contribute to a lower wound complication rate. A two incision approach allows not necessarily for a stronger construct as some studies are controversial, but for a more accurate reduction and restoration of alignment.OrthoCash 2020Which of the following is true regarding the use of the saline injection load test to diagnose traumatic knee arthrotomies?Addition of methylene blue to the saline load test increases the sensitivity of the testInjection of 110ml of saline will diagnose 95% of knee arthrotomiesInjection of 175ml of saline will diagnose 99% of knee arthrotomiesA superomedial injection location requires significantly less fluid than a inferoeromedial injection locationA history and physical exam by an orthopaedic surgeon has equivalent sensitivity to saline load test at detecting a traumatic arthrotomyInjection of 175ml of saline will diagnose 99% of knee arthrotomies.Clinical evaluation alone to determine if a periarticular laceration has penetrated the joint can often be incorrect. A Saline Load Test (SLT) is an effective methods to detect intraarticular penetration. New studies have shown addition of methylene blue does not improve the diagnostic value of the saline load test. The use of a CT scan can be helpful, especially in the presence of intra-articular air.Voit et al. investigated the sensitivity of the clinical exam and a saline load test in 50 consecutive patients with periarticular lacerations suggestive of joint penetration. In 14 there was leakage of fluid on saline load test. In six of these patients, the clinician had judged there was no traumatic arthrotomy based on physical exam and clinical history. They therefore concluded performing a saline load test is important adjunct and the clinical exam alone can not be relied on to detect traumatic arthrotomies.Nord et al. found that the volumes of saline that were needed in order to effectively diagnose 75%, 90%, 95%, and 99% of the knee arthrotomies were110, 145, 155, and 175 mL, respectively. They also found that an inferomedial injection location required significantly less fluid than a superomedial injection location did.Metzger et al. studied 58 patients that underwent saline load test with about 100ml of saline injected (methylene blue 29, normal saline 29). They found that the false-negative rate was 67% (methylene blue 69%, normal saline 66%). They concluded the addition of methylene blue does not improve the diagnostic value of the saline load test.Konda et al. performed a study evaluationg the role of CT scan versus saline load test. They found that the sensitivity and specificity of the CT scan to detect traumatic arthrotomy was 100%. In a subgroup of 37 patients that received both a CT scan and the conventional saline load test, the sensitivity and specificity of the CT scan was 100% compared to 92% for the saline load test (p<0.001).Incorrect Answers:OrthoCash 2020A 36-year-old rancher is involved in a tractor roll-over accident and sustains the injury shown in Figure A to his dominant right arm. After undergoing rigid anatomic fixation of the fracture, the distal radio-ulnar joint (DRUJ) remains incongruent. What is the next step in management?Revision plating of the fractureRevision reduction and intramedullary fixationReduction of interposed extensor carpi ulnaris tendonReduction of interposed pronator quadratus tendonReduction of interposed flexor carpi ulnaris tendonCorrent answer: 3The most likely cause of persistent DRUJ incongruity after anatomic reduction and fixation of the radial shaft fracture of the answers above is interposition of the extensor carpi ulnaris (ECU) tendon. The tendon must be extricated from the joint to permit DRUJ reduction.Gaeleazzi fracture-dislocations, such as that seen in Figure A, are typically stable once the radial shaft fracture is anatomically reduced. After fixation, the DRUJ is translated in pronation, supination, and in a neutral position to test for stability. A “clunk” during passive motion of the DRUJ is further evidence of gross instability. Gross laxity can be treated by splinting in supination or by pinning the DRUJ. However, ECU tendon interposition has been reported as a possible cause of a persistently irreducible DRUJ. Radiographic findings typically demonstrate a dorsally displaced ulnar head and a widened DRUJ. The interposed tendon must be removed from the joint, often through a separate dorsal approach to permit DRUJ reduction.Bruckner et al. review the evaluation and management of complex dislocations of the DRUJ. The authors note that these injuries are associated with frequent irreducibility, recurrent subluxation, or soft reduction of the DRUJ secondary to interposed tissue. In their institutional series, four of the 11 cases of Galeazzi fractures were associated with complex DRUJ dislocations, most commonly due to displacement of the ECU tendon volar to the ulna, necessitating open reduction. They cautioned that unobtainable or unconvincing reductions should warrant surgical exploration.Paley et al. reported two cases of an irreducible DRUJ after radial shaft fracture fixation. The authors describe an empty ECU tendon sulcus on the dorsum of the wrist in both cases. One case was noted and addressed intraoperatively.However, the second case was not identified and this patient went on to endure persistent subluxation and diastasis of the DRUJ, ultimately experiencing a poor result. The authors advocate a separate dorsal exposure to reduce the ECU.Hanel and Scheid reported a case of entrapment of the ECU in the DRUJ in a skeletal immature 12 year old boy. They noted that intraoperative radiographic analysis was significant for a widened DRUJ and dorsally displaced ulnar head. These authors too advocated a separate dorsal exposure to approach and extricate the ECU tendon.Incorrect answersOrthoCash 2020A 58-year-old right-hand-dominant computer programmer trips and falls onto his right arm. He reports right arm pain and that his elbow felt "sloppy". His initial lateral radiograph is shown in Figure A. The orthopedic junior resident counsels him that he will likely need a radial head arthroplasty, ligament repair, and possible fixation of the ulna. What factor would most significantly affect the decision to surgically address the ulna fracture?Degree of radial head comminutionThe deforming force acting on the avulsed fracture fragmentSize of fragment and elbow stability after radial head replacementThe degree of fracture displacementPatient age and bone qualityCorrent answer: 3The size of the fragment and degree of elbow instability following radial head fixation or replacement most often determines the intraoperative decision on coronoid fragment fixation.The radial head is a secondary restraint to posterolateral rotatory instability (PLRI) of the elbow, while the coronoid provides an anterior and varus buttress to the ulnohumeral joint, resisting posterior dislocation. The medial ulnar collateral ligament attaches to the anteromedial facet of the coronoid, so large medial facet fractures may displace and cause varus posteromedial instability (PMRI). However, in terrible triad injuries (causing PLRI), small coronoid tip fractures are more common. These are typically left as they most often do not contribute to elbow instability. Therefore in most cases, radial head replacement and lateral ligamentous repair are sufficient to restore stability.However larger coronoid base fractures may require fixation in order to stabilize the elbow. In these cases, the coronoid fracture may be addressed through the lateral window after radial head resection and before the trial implant is assessed. The anterior capsule can be tied down to the ulna or if the fracture is large enough, it may sometimes tolerate internal fixation.Conversely, a buttress plate for the coronoid may be applied via a medial approach in the setting of a large coronoid base fracture as in PMRI.Ring et al. reviewed 11 terrible triad injuries including 7 of which had the radial head surgically addressed and 4 of which had undergone radial head excision. The authors found that all four patients who underwent radial head excision dislocated after surgery. Only four patients had a satisfactory result, and all of these had fixation of the radial head, two requiring concomitant repair of the lateral ulnar collateral ligament (LUCL). The authors concluded that terrible triad injuries were unstable, prone to redislocation and that radiocapitellar contact is critical for ulnohumeral stability.Pugh et al. reviewed 36 cases of terrible triad injuries in which all coronoid fractures were addressed, either with screw fixation or suture repair of the anterior capsule. The authors reported that the average arc of motion postoperatively was 112 degrees, Mayo score was 88, and concentric stability was restored in 34/36. There were 8 complications requiring re-operation. They concluded that coronoid fixation with radial head fixation or replacement yields a stable elbow suitable for early motion.Schneeberger et al. evaluated elbow instability after simulated terrible triad injuries. They found that radial head excision even in the setting of an intact LUCL lead to posterolateral laxity. Furthermore, if 30% of the coronoid tip was excised, the elbow dislocated at 60 degrees of flexion, but stability was restored with a radial head replacement. However, if 50% of the coronoid wasexcised, even with a radial head replacement dislocation occurred. They concluded that so long as the radial head is replaced, small coronoid fractures may not need to be repaired.Figure A demonstrates a comminuted radial head fracture, a small coronoid fracture, and subluxation of the ulnohumeral joint.Incorrect answers:OrthoCash 2020What is the most appropriate plating technique utilized for the medial malleolus fracture typically seen in a displaced supination-adduction ankle fracture?Tension band platingAntiglide platingBridge platingNeutralization platingSubmuscular platingA supination-adduction ankle fracture leads to a vertical fracture of the medial malleolus. Traditional fixation of the medial malleolus with oblique screws from the tip of the malleolus directed proximally will ineffectively protect against shear forces at the fracture site; these also are directed quite obliquely to the vertical fracture line, and therefore have poor biomechanical resistance to failure. An antiglide plate is used medially to prevent displacement of the fracture segment due to shear forces.According to the referenced article by Toolan et al, placement of two horizontal (perpendicular to the fracture line) lag screws from medial to lateral arebiomechanically the most important aspect of the construct whether a plate is used or not.OrthoCash 2020A 25-year-old Norwegian amateur curler slips on the ice, falling onto an outstretched right elbow. He is taken to the local teaching hospital and radiographs demonstrate a significantly comminuted radial head fracture and coronoid base fracture. His elbow is reduced and splinted. To restore stability and allow early range of motion, which of the following will most likely need to be performed in most cases?Radial head fixation or replacementRadial head fixation or replacement and coronoid fixationRadial head fixation or replacement, coronoid fixation, and lateral ulnar collateral ligament (LUCL) repairRadial head fixation or replacement, coronoid fixation, LUCL and medial ulnar collateral ligament (MUCL) repairRadial head fixation or replacement, coronoid fixation, LUCL and MUCL repair, and application of a hinged fixatorThe patient has sustained a "terrible triad" injury, classically involving a radial head fracture, coronoid fracture, and elbow dislocation. These often involve LUCL injuries and a traumatic injury in the radiocapitellar joint. Stability is achieved with radial head replacement (or fixation), coronoid fixation (in cases with a large coronoid fracture), and lateral soft tissue repair.Posterolateral rotatory instability (PLRI) following a terrible triad injury is usually caused by a fall on an extended arm that produces a valgus, axial, and rotatory force. The mechanism of injury begins laterally and moves medially.Hence, the LUCL fails first, followed by the anterior capsule (or coronoid), and lastly the MUCL. Even following fixation, patients often lose some degree of their flexion-extension arc, may develop post-traumatic arthritis, or most commonly may have persistent instability. The radial head is a primary restraint to PLRI and must be either replaced with a prosthesis or fixed in the setting of a terrible triad injury. Replacement is typically chosen when the radial head is in more than 3 fragments. Coronoid fractures should be fixed when they involve >30-50% of the coronoid base. However, the best way to determine if coronoid fixation is necessary is with an intraoperative fluoroscopic examination.Forthman et al. reviewed outcomes following the management of 34 elbow fracture-dislocations. In all cases, the radial head was replaced or underwent fixation. The MUCL was not repaired in any case. The authors noted only 2 cases of post-operative instability, one terrible triad, and one combined capitellum and trochlea fracture. The authors noted that both cases were related to non-compliance. The remaining 32 averaged 120 degrees of flexion-extension and 74% had good-excellent outcomes. The authors concluded that MUCL repair is not required for elbow dislocations so long as the radial head, large coronoid fractures, and LUCL are addressed.Schneeberger et al. evaluated elbow instability after simulated terrible triad injuries. They found that radial head excision even in the setting of an intact LCL leads to posterolateral laxity. If 30% of the coronoid was excised, the elbow dislocated at 60 degrees of flexion, but stability was restored with a radial head replacement. However, if 50% of the coronoid was excised, even with a radial head replacement, dislocation occurred. This led the authors to conclude that long as the radial head was replaced, small coronoid fractures may not need to be repaired.Papatheodorou et al. reviewed 14 terrible triad injuries (all of which had Regan-Morrey type 1 or 2 coronoid fractures) that underwent surgical fixation or replacement of the radial head combined with LUCL repair. The authors noted that intraoperative stability was confirmed in all cases without coronoid fixation, MCL repair, or an external fixator. The authors concluded that coronoid fixation is not required in fractures up to 50% the height of the coronoid and that MCL repair is not necessary.Incorrect answers:OrthoCash 2020A 32-year-old female sustains the injury shown in Video A. The right-sided pelvic injury is best classified as which of the following?Lateral compression 1Lateral compression 2Vertical shearAnterior-posterior compression 2Anterior-posterior compression 3The injury shown in Video V reveals a right sided posterior ilium fracture, which is known as a crescent fracture. The presence of a crescent fracture is consistent with a lateral compression type 2 injury; this differentiates this from a type I injury. The ipsilateral anterior sacrum has a small impaction injury anteriorly while the contralateral SI joint has a minor amount of anterior sacral impaction indicative of a lateral compression type I injury.The reference by Burgess et al is the primary source of the mechanism classification of pelvic ring injuries. Overall blood replacement averaged 5.9 units (lateral compression, 3.6 units; anteroposterior compression, 14.8 units; vertical shear, 9.2 units; combined mechanical, 8.5 units). Overall mortality was 8.6% (lateral compression, 7.0%; anteroposterior, 20.0%, vertical shear,0%; combined mechanical, 18.0%).Incorrect answers:1: The presence of a crescent fracture means this is at least a LC-2 injury. The left-sided fracture pattern is consistent with an LC-1 pattern.3: A vertical shear fracture pattern would exhibit some vertical displacement and does not typically exhibit the crescent fragment.4: The fracture pattern does not match an anterior-posterior compression pattern.5: The fracture pattern does not match an anterior-posterior compression pattern.OrthoCash 2020A 35-year-old zookeeper fell 10 feet while preparing an exhibit for a grand reopening, landing on his left arm. The patient is then evaluated by a keen orthopedic resident in the emergency room who describes the zookeeper's injuries to his chief. He describes a comminuted radial head fracture and posterolateral ulnohumeral dislocation. The chief resident orders a CT scan which demonstrates a coronoid fracture involving 50% the height with no involvement of the anteromedial facet. During surgery, the trauma surgeon replaces the radial head and repairs the lateral collateral ligament complex. Theelbow is splinted in elbow flexion and pronation. The patient begins range of motion exercises with her occupational therapist 3 days after surgery, and her elbow dislocates. What is the most likely reason for her instability?Length of immobilizationPosition of immobilizationLack of coronoid fixation with medial buttress plateLack of coronoid fixation from lateral approachLack of medial collateral ligament repairCorrent answer: 4The zookeeper sustained a "terrible triad" injury with resulting posterolateral rotatory instability (PLRI). To prevent post-operative instability, large coronoid fractures should be fixed, and this would be performed through a lateral approach given that the radial head will be replaced.The coronoid serves as an anterior and varus buttress to the ulnohumeral joint, resisting posterior dislocation. Though the coronoid tip has no soft tissue attachments, the medial ulnar collateral ligament attaches to the anteromedial facet of the coronoid. A coronoid fracture through the anteromedial facet, such as in the setting of posteroMEDIAL rotatory instability, would require a medial buttress plate to restore varus stability. In a coronoid base fracture involving 50% of the coronoid, fixation is required even when a radial head arthroplasty is performed. This can be done with suture fixation via a bone tunnel through the ulna or with screws from dorsal to volar. Failure to fix a large coronoid base fracture would result in persistent instability, as with the patient in this vignette.Ring et al. reviewed 11 terrible triad injuries - including 7 of which had the radial head surgically addressed and 4 of which underwent radial head excision. They noted that all four patients who underwent radial head excision dislocated after surgery. Moreover, only four patients had a satisfactory result, and all of these had fixation of the radial head, with two requiring concomitant repair of the lateral ulnar collateral ligament (LUCL). The authors concluded that terrible triad injuries are unstable, prone to redislocation and that radiocapitellar contact is critical for ulnohumeral stability.Schneeberger et al. evaluated elbow instability after simulated terrible triad injuries. They showed that radial head excision even with an intact LUCL resulted in persistent posterolateral laxity. If 30% of the coronoid was excised, the elbow dislocated at 60 degrees of flexion, but stability was restored with a radial head replacement alone. If 50% of the coronoid was excised, even witha radial head replacement, dislocation occurred. The authors concluded that so long as the radial head was replaced, small coronoid fractures may not need to be repaired, but large fractures involving 50% or more would require fixation even if the radial head and LUCL were addressed.Moro et al. treated 25 unreconstructible radial head fractures with a metal radial head arthroplasty. The authors reported a DASH score of 17, PRWE of 17, and Mayo elbow score of 80. Poor outcomes were seen in those with psychiatric disorders or those involved in a worker's compensation claim. The authors reported that radial head arthroplasty resulted in stable elbows with mild-moderate physical impairment.Ring, Quintero, and Jupiter reviewed 56 patients with radial head fractures who underwent surgical fixation. Of the comminuted Mason type-3 fractures that underwent ORIF, they found that 13/14 had a poor result. The authors recommend that fractures with 3 or fewer fragments are amenable to fixation while those with 4 or more articular fragments are not.Incorrect answers:OrthoCash 2020Which of the following injuries would require plating of the radius along with closed reduction and evaluation of the distal radioulnar joint (DRUJ)?Nightstick fractureGaleazzi fractureMonteggia fractureRolando fractureSmith fractureA Galeazzi fracture is a fracture of the distal third of the radius with dislocation of the distal radioulnar joint. It commonly results from a fall onto an outstretched hand with the forearm in pronation.A Galeazzi fracture is an injury that requires surgical treatment in an adult. The algorithm includes anatomic reduction and fixation of the radial shaft, and closed reduction of the DRUJ with assessment of stability. If the DRUJ remains unstable, supination of the wrist may reduce the DRUJ. Otherwise, either open or closed reduction with pinning can be undertaken to stabilize the joint. The closer the radius fracture is to the DRUJ, the more likely it is to be unstable.Acute intervention results in improved outcomes as compared to delayed reconstruction.Rettig et al. retrospectively analyzed 40 patients with Galeazzi fracture-dislocations that were treated with open reduction and internal fixation of the radial shaft fracture. They noted that a radial shaft fracture located within

The clinical presentation is consistent with a Chance fracture of the spine. These fractures are often associated with concomitant bowel injury.A Chance fracture injury is a flexion-distraction injury of the spine. The anterior column (vertebral body) collapses under compression and the posterior elements fail under tension (rupture of the interspinous ligaments or avulsion fracture of the spinous process). A common mechanism is a MVA where the child is wearing a seatbelt, leading to a "seatbelt sign". In the presence of a "seatbelt" sign, on should have a high suspicion for a bowel injury.Reid et al. reported seven cases of pediatric patients with Chance fractures. All had associated intraabdominal bowel injury.Holland et al. retrospectively reviewed 28 pediatric patients with Chance fractures, 71% sustained following road trauma. Eleven percent had associated small bowel injury, but all patients had abnormal abdominal CT scans.Figure A is a clinical photo of a 'seatbelt sign' following a motor vehicle accident. Figure B exhibits a "bony" Chance fracture where the spinous process has been avulsed. Illustration A depict the failure of the anterior column under compression and failure of the posterior column under tension.Incorrect answers:(SBQ12SP.32) A 48-year-old man is involved in a motor vehicle accident and is taken to an outside hospital where he undergoes CT imaging, displayed in Figures A-B. Approximately 36 hours later he is transferred to your hospital for further evaluation and management. On exam, he has tenderness over his upper cervical spine and is neurologically intact with no myelopathic signs. What is the most appropriate treatment method for this patient and why?ReviewTopicSoft cervical orthosis because his gender puts him at a low risk of nonunion.Halo vest immobilization because the degree of fracture displacement puts him at a low risk of nonunion.Anterior screw fixation because his delayed time to treatment puts him at an high risk of nonunion.Posterior C1-C2 fusion with rigid instrumentation because his age puts him at a high risk of nonunion.Posterior C1-C2 fusion with sublaminar wiring because the degree of fracture angulation puts him at a high risk of nonunion.The patient has a type II odontoid fracture and should be managed with halo vest immobilization as he has minimal fracture displacement (< 5mm) and no other risk factors for nonunion.Type II odontoid fractures comprise 35% of all C2 fractures and have the highest nonunion rate. Commonly cited risk factors for nonunion include posterior displacement, posterior angulation, delayed initiation of treatment, fracture comminution and advanced age. Patients without these risk factors can often be successfully managed with halo vest immobilization. Elderly patients are frequently unable to tolerate halo vest immobilization and can be placed in a rigid cervical orthosis. Patients at high risk for nonunion are generally managed surgically with either anterior screw fixation, posterior rigid fixation (C1-C2 transarticular screw construct versus C1 lateral mass screw + C2 pedicle screw construct), or posterior C1-C2 sublaminar wiring.Greene et al found that type II odonotoid fractures that were displaced >/= 6mm had a nonunion rate of 86% compared to 18% in patients with < 6mm displacement. This was statistically significant regardless of direction of displacement. Age was not significantly associated with nonunion.Koivikko et al performed a retrospective review of conservatively treated type II odontoid fractures and identified risk factors for nonunion. Fracture gap > 1mm, posterior displacement > 5mm, posterior angulation > 20°, delayed start of treatment> 4 days and posterior redisplacement > 2mm were all correlated with nonunion. In this study, anterior displacement, gender and age were unrelated to nonunion.Figures A and B are coronal and sagittal CT scans of the cervical spine, respectively, demonstrating a noncomminuted type II odontoid fracture with minimal posterior displacement and angulation.IncorrectResponses:

DISCUSSION: Patients who are in compensated shock have normal vital signs but still have hypoperfusion of organ beds such as the splanchnic circulation due to preferential perfusion of the heart and brain. The response to this continued hypoperfusion may be the development of a systemic inflammatory response that may lead to multiple organ failure. The patients are thought to be at risk for a “primed” immune system due to the ongoing stimulation of the immune system and may have an exaggerated response to a second stimulus such as surgery or infection. Other markers of resuscitation should be used besides vital signs to determine when resuscitation has been completed. The use of temporizing fixation has been shown to lower systemic complication rates, and the infection and union rate after staged fixation is not altered. REFERENCES: Schulman AM, Claridge JA, Carr G, et al: Predictors of patients who will develop prolonged occult hypoperfusion following blunt trauma. J Trauma 2004;57:795-800. Tisherman SA, Barie P, Bokhari F, et al: Clinical practice guideline: Endpoints of resuscitation. J Trauma 2004;57:898-912.

DISCUSSION: The patient's plain radiographs demonstrate a bicondylar tibial plateau fracture with complete separation of the diaphysis from the epiphysis, making this a Schatzker VI injury. Clinically, the patient is neurovascularly intact with symmetric palpable pulses, and ankle brachial indices are not necessary. There is significant lateral tibial plateau displacement with the lateral femoral condyle down into the plateau defect. Considering the swelling, abrasions, and severity of the injury, a bridging external fixator is warranted followed by CT imaging. The ligamentotaxis will provide better definition of the injury and joint fragments and allow for soft-tissue rest and subsidence of the swelling for eventual surgical intervention. Oblique views will not add as much information as CT imaging, which will show the bicondylar nature of the injury and the proximal tibia essentially split centrally with the tubercle as a separate fragment. A midline incision with medial and lateral plating has fallen out of favor secondary to wound-healing complications. Comminution of the metaphysis or the lateral side is not an absolute indication for a medial plate. Open lateral fractures can still be managed with a laterally based plate depending on the soft-tissue injury. RECOMMENDED READINGS: Higgins TF, Kemper D, Klatt J. Incidence and morphology of the posteromedial fragment in bicondylar tibial plateau fractures. J Orthop Trauma. 2009 Jan;23(1):45-51. Higgins TF, Klatt J, Bachus KN. Biomechanical analysis of bicondylar tibial plateau fixation: how does lateral locking plate fixation compare to dual plate fixation? J Orthop Trauma. 2007 May;21(5):301-6. Barei DP, O'Mara TJ, Taitsman LA, Dunbar RP, Nork SE. Frequency and fracture morphology of the posteromedial fragment in bicondylar tibial plateau fracture patterns. J Orthop Trauma. 2008 Mar;22(3):176-82.

Reamed exchange intramedullary nailing of diaphyseal tibial shaft fractures in which there is less than 30% of cortical bone loss can achieve union rates ranging between 76%-96%. In a review article, Brinker et al discusses the indications and limitations of exchange nailing of ununited fractures. Biological as well as mechanical factors contribute to the healing of nonunions. Anatomically, multiple studies cited in this review article demonstrate that distal femoral nonunions do not readily achieve union following exchange nailing. Humerus nonunions, both diaphyseal and proximal locations, more readily achieve union with plate fixation and bone grafting according to articles cited in this review as well. Banaszkiewicz et al also discusses the difficulties with exchange nailing of femoral nonunions with a large percentage of patients requiring additional surgeries to achieve union. Templeman et al discusses the successful results of reamed exchange intramedullary nailing of delayed union and nonunion of the tibial shaft. The authors recommend the use of bone graft only when there is substantial bone loss, usually exceeding 30% of the cortical diameter.

The radiograph reveals an anterior posterior compression injury to the pelvic ring which is commonly seen after horseback riding injuries. In a large series of patients with this type of injury, 18 of 20 patients had sexual dysfunction after sustaining this injury. Posttraumatic osteoarthritis of the sacroiliac joints may occur, but is less common in this type of injury. Chronic low back pain, gait abnormalities, and quadriceps weakness are not typically seen with this type of injury.

The highest mortality rate after a pelvic fracture is associated with hypovolemic shock, most of which is secondary to extensive intrapelvic arterial injuries.

A compartment syndrome is best diagnosed with a "deltaP" (diastolic pressure minus compartment pressure) of less than or equal to 30 mm Hg. This patient is hypotensive and the "deltaPs" are all less than 30 mm Hg. Emergent fasciotomy is the preferred treatment.

Although flexible intramedullary nails are a good treatment alternative for femoral shaft fractures in older children, patients weighing more than 100 pounds have a higher incidence of complications that include bending of the nails. Therefore, transtrochanteric solid intramedullary nail fixation is most likely the best option for this patient. Using a greater trochanteric entry point avoids the piriformis fossa and the possibility of osteonecrosis. External fixation is not a good alternative for this patient because of the transverse nature of the fracture. External fixation of this fracture pattern has been associated with a high refracture rate. Traction and casting can be performed but results in a lengthy hospital stay and a very large cast in an overweight 10-year-old child.

DISCUSSION: The patient has a prefractured stage of congenital pseudarthrosis of the tibia and is at risk for fracture. The PTB orthosis may prevent or delay the fracture. Osteotomy is frequently complicated by nonunion. When established nonunion does not respond to intramedullary nailing and bone grafting, vascularized grafting may succeed. Amputation is a salvage procedure. REFERENCES: Murray HH, Lovell WW: Congenital pseudarthrosis of the tibia: A long-term follow-up study. Clin Orthop 1982;166:14-20. Crossett LS, Beaty JH, Betz RR, et al: Congenital pseudarthrosis of the tibia: Long-term follow-up study. Clin Orthop 1989;245:16-18.

DISCUSSION: Frankle et al found that passive external rotation of the shoulder placed the most stress on the lesser tuberosity fixation. The subscapularis tendon inserts on the lesser tuberosity and is the deforming force when placed under tension during external rotation. They also found that non-anatomic tuberosity reduction of 4-part proximal humerus fractures treated with hemiarthroplasty increased torque and impaired external rotation kinematics.

What is the most common organism implicated in periprosthetic infection of the shoulder?A. Methicillin-resistant Staphylococcus aureus (MRSA)B. Cutibacterium acnesC. Enterococcus speciesD. Staphylococcus epidermidisC acnes is the most common organism recovered in prosthetic shoulder infections (33%), Coagulase-negative Staphylococcus is second (21%), Methicillin-sensitive S aureus (13%), and S epidermidis (10%). MRSA accounts for 5% and Enterococcus species, 1.5%.

The radiographs reveal a fracture entering the 4-5 intermetatarsal articulation, consistent with a zone 2 injury. This classically is also referred to as a Jones fracture. The history and radiographic findings indicate this is an acute fracture, which guides management. A zone 1 fracture enters the fifth tarsometatarsal joint, and a zone 3 fracture is a proximal diaphyseal fracture distal to the 4-5 articulation. Initial management is usually nonsurgical and consists of non-weight-bearing in a short leg cast. This method has been shown to result in a better healing rate compared to weight bearing as tolerated.

The patient has severe hemophilia with a volar forearm hemorrhage and an emerging compartment syndrome. Therefore, it is critical to normalize the clotting deficiency as the first step in treatment. In a patient who has a factor VIII level of less than 1% and no inhibitors to factor VIII, transfusion with 4 unit/kg will typically raise the factor VIII level to 100%. Continuous transfusion can then be used to maintain this level. Compartment pressures can be safely measured after infusion of factor VIII. Because the hemorrhage is of limited duration and any surgery is considered serious in a patient with hemophilia, the compartment pressure should be measured before making a decision regarding a fasciotomy. However, it is important to note that the use of factor VIII concentrates allows both emergency and elective surgery provided that adequate hematology backup is available. Splinting the elbow and wrist in flexion reduces the pressure in the volar compartments, protects the forearm from further trauma, and makes the patient more comfortable.

Glenoid exposure, while better than with surface replacements, is not improved over traditional stemmed replacements. Metaphyseal comminution would make it unlikely that a stemless implant could be used in most four-part fractures. Stemless replacement does have the unique advantage of allowing placement of a prosthesis with a malunion without an osteotomy, as the prosthesis is not constrained by the position of the stem. While early results are encouraging, there is no long-term data to suggest that survivorship is increasedwith stemless arthroplasty.

The radiographs reveal an extra-articular proximal phalanx fracture of the index finger. The fracture is comminuted with dorsal angulation of the distal fragment. The question specifically asks about the restoration of sagittal alignment. The fracture is comminuted with dorsal angulation of the distal fragment. The other options are incorrect, because overlapping of the digits occurs with rotational malalignment, the development of arthritis may occur with intra-articular fractures, and hyperextension would not occur with this type of deformity.

The patient has an isolated closed injury involving the humeral diaphysis. The lack of wrist and finger extension indicates injury to the radial nerve. Based on these findings, ongoing observation of the nerve is warranted with delayed exploration after 3 to 4 months if there are no signs of progressive return of nerve function. Treatment of the fracture should include external immobilization and fracture bracing. An indication for nerve exploration and surgical stabilization would be an open fracture.