Orthopedic Trauma MCQs: Acute Fracture & ABOS Prep

Question 1

A 26-year-old woman sustained a nondisplaced femoral neck fracture and treatment consisted of use of percutaneous cannulated screws. At her 3-month follow-up visit, she reports hip pain and is unable to ambulate. A radiograph is shown in Figure 1. What is the next most appropriate treatment?

Explanation

Femoral neck fracture nonunion is a challenging problem for orthopaedic surgeons. Vertical fractures are more prone to nonunion due to shear stress rather than compressive forces across the fracture site. Several authors have suggested these fractures are more common in young adults due to injury type and bone composition. It is widely regarded that an effort should be made to salvage the femoral head if vascularity remains. The most common method to treat this complication is valgus intertrochanteric osteotomy of the femur. This functionally makes a vertical fracture more horizontal, converting shear into compressive forces. It also helps correct the varus position of the fracture nonunion. Hartford JM, Patel A, Powell J: Intertrochanteric osteotomy using a dynamic hip screw for femoral neck nonunion. J Orthop Trauma 2005;19:329-333.

Question 2

Which of the following choices best describes the fracture pattern shown in Figures 2a through 2c?

Explanation

The fracture pattern shown in the radiographs is a fracture of the posterior column. The only line interrupted on the AP pelvis is the ilioischial line. The obturator oblique view shows that the iliopectineal line is intact as is the outline of the posterior wall. The iliac oblique view shows an interruption of the ilioischial line and an intact anterior wall. Therefore, this fracture is a fracture of the posterior column. Letournel E, Judet R: Fractures of the Acetabulum, ed 2. Berlin, Germany, Springer Verlag, 1993.

Question 3

The correct starting point for an external fixation half pin placed into the anterior inferior iliac spine (AIIS) is labeled by what letter in Figure 3?

Explanation

Half pins placed in the AIIS are an alternative to pins placed in the iliac crest. A strong pillar of bone runs from the AIIS to the posterior iliac crest and less soft tissue is typically present in this area. The starting point is best seen on an obturator outlet view. The obturator outlet view is a combination of the pelvic outlet view and the obturator view of Judet and Letournel. The beam is rotated "over the top" of the patient since the iliac wing is externally rotated as well as cephalad to best visualize this column of bone running from the AIIS to the posterior iliac spine. This corridor of bone will appear as a teardrop. Once the correct view is obtained, the pin should be started at least 2 cm proximal to the hip joint to avoid placing a pin within the hip capsule. Blunt dissection and a guide sleeve should be used to prevent damage to the lateral femoral cutaneous nerve. An iliac oblique view is used after the pin has been partially inserted to make sure the pin is passing superior to the superior gluteal notch, and an obturator inlet view can be used at the completion of the procedure to make sure the pin is contained within the bone for its entire length. Gardner MJ, Nork SE: Stabilization of unstable pelvic fractures with supra-acetabular compression external fixation. J Orthop Trauma 2007;21:269-273. Haidukewych GJ, Kumar S, Prpa B: Placement of half-pins for supra-acetabular external fixation: An anatomic study. Clin Orthop Relat Res 2003;411:269-273.

Question 4

Figures 4a and 4b show the radiographs of a 53-year-old woman who was injured in a fall. After initial closed reduction, what is the preferred treatment for this fracture?

Explanation

This elbow fracture-dislocation involves a radial head fracture, coronoid fracture, and ulnohumeral dislocation (terrible triad). Several algorithms exist for treatment; surgical treatment is indicated. The treatment should address the radial head. Studies have shown replacement to be superior to repair in comminuted fractures. The coronoid may be addressed in unstable cases at the time of radial head excision and replacement. Lateral ligamentous repair is carried out during closure of the lateral elbow capsule. Medial ligamentous repair also may be undertaken but usually in concert with bony repair. Hinged external fixation remains an option when instability exists following bony and soft-tissue repair. Acute ulnar nerve transposition is rarely indicated. Ring D, Jupiter JB, Zilberfarb J: Posterior dislocation of the elbow with fractures of the radial head and coronoid. J Bone Joint Surg Am 2002;84:547-551.

Question 5

A 25-year-old semiprofessional football player sustains a hyperextension injury to the left foot. He is unable to bear weight. Examination reveals tenderness along the midfoot with swelling and plantar ecchymosis. Radiographs are negative. What is the next step in evaluation of this patient?

Explanation

The patient has a suspected Lisfranc sprain based on the plantar ecchymosis. The first step in diagnosis is a dynamic radiographic study. This should include a physician-assisted midfoot stress examination or standing weight-bearing radiographs to evaluate for displacement. There is no evidence of compartment syndrome, and a bone scan, CT, and MRI are expensive tests that are not warranted. Early JS: Fractures and dislocations of the midfoot and forefoot, in Bucholz R, Heckman JD, Court-Brown CM (eds): Rockwood and Green's Fractures in Adults. Philadelphia, PA, Lippincott Williams and Wilkins, 2006, pp 2337-2400.

Question 6

A 52-year-old woman slips in her bathroom and strikes her right hand on a cabinet. She notes swelling, ecchymosis, and pain with attempted motion. There are no open wounds. Radiographs are shown in Figures 5a through 5c. What is the most appropriate treatment?

Explanation

Nondisplaced transverse fractures of the phalanges are stable. Immobilization in the intrinsic plus position will prevent MCP joint stiffness. Displaced oblique fractures are more at risk for instability. Stern PJ: Fractures of the metacarpals and phalanges, in Green DP, Hotchkiss RN, Pederson WC, et al (eds): Green's Operative Hand Surgery, ed 5. Philadelphia, PA, Elsevier, 2005, p 281.

Question 7

A 19-year-old college student reports a 1-week history of wrist pain following an intramural rugby match. A PA radiograph is shown in Figure 6. He denies any prior wrist injury. What is the best course of action?

Explanation

The patient has a scaphoid fracture involving the proximal pole. Surgical treatment is recommended for such fractures because of the prolonged period of cast immobilization necessary and the increased risk of delayed union, nonunion, and/or osteonecrosis with nonsurgical management. A cannulated compression screw, inserted in the central scaphoid via a dorsal approach, is biomechanically advantageous and provides greater stability for fracture healing than Kirschner wires. Recently, good outcomes have been reported with arthroscopic-assisted percutaneous fixation of nondisplaced or minimally displaced scaphoid fractures. Rettig ME, Raskin KB: Retrograde compression screw fixation of acute proximal pole scaphoid fractures. J Hand Surg Am 1999;24:1206-1210. Chan KW, McAdams TR: Central screw placement in percutaneous screw scaphoid fixation: A cadaveric comparison of proximal and distal techniques. J Hand Surg Am 2004;29:74-79. Bedi A, Jebson PJ, Hayden RJ, et al: Internal fixation of acute non-displaced scaphoid waist fractures via a limited dorsal approach: An assessment or radiographic and functional outcomes. J Hand Surg Am 2007;32:326-333.

Question 8

A 29-year-old woman was injured in a high-speed motor vehicle accident 3 hours ago. Radiographs are shown in Figures 7a through 7e. Her right foot injury is open and contaminated. Her associated injuries include a closed head injury and a ruptured spleen requiring resection. She has had 6 units of packed red blood cells and the trauma surgeon has turned her care over to you. Her current base deficit is 10 and her urinary output has averaged 0.4 mL/kg for the last 2 hours. What is the best treatment at this time?

Explanation

The patient appears to be a borderline or unstable surgical patient following her initial trauma and spleenectomy (high base excess and low urine output). She needs continued resuscitation and minimal additional blood loss. This is best accomplished with irrigation and debridement of the ankle, external fixation of the ankle, foot, and femur, and splinting of the forearm. A traction pin for the femoral fracture will not control bleeding as well as an external fixator. Intramedullary nailing of the femur and open reduction and internal fixation of the forearm would be appropriate in patients that are euvolemic and stable. Pape HC, Hildebrand F, Pertschy S, et al: Changes in the management of femoral shaft fractures in polytrauma patients: From early total care to damage control orthopedic surgery. J Trauma 2002;53:452-461. Taeger G, Ruchholtz S, Waydhas C, et al: Damage control orthopedics in patients with multiple injuries is effective, time saving, and safe. J Trauma 2005;59:409-416. Harwood PJ, Giannoudis PV, van Griensven M, et al: Alterations in the systemic inflammatory response after early total care and damage control procedures for femoral shaft fracture in severely injured patients. J Trauma 2005;58:446-452.

Question 9

A 45-year-old man who is a smoker has a significant hemothorax and bilateral closed femoral fractures. On insertion of a chest tube, 1,100 mL of blood was returned. He has had 75 mL of chest tube output over the last 2 hours while being resuscitated in the ICU. His base deficit is now 2 and his urine output has been 3 mL/kg over the last hour. What is the next most appropriate step in management?

Explanation

Although this patient had a hemothorax, the bleeding has stopped and he has been resuscitated to a euvolemic status with a small base deficit and good urine output. External fixation of both femurs is an option but an unnecessary step in the treatment algorithm. Nork SE, Agel J, Russell GV, et al: Mortality after reamed intramedullary nailing of bilateral femur fractures. Clin Orthop Relat Res 2003;415:272-278.

Question 10

A 47-year-old woman falls and sustains a direct blow to her middle finger. She notes pain and swelling and is unable to move the proximal interphalangeal (PIP) or distal interphalangeal (DIP) joints. Radiographs are shown in Figures 8a through 8c. Proper management should consist of

Explanation

The oblique nature of the fracture and extension of the fracture to the condyles implies an unstable fracture. Lag screw fixation provides an excellent chance of union, and the ability to start early range of motion. Stern PJ: Fractures of the metacarpals and phalanges, in Green DP, Hotchkiss RN, Pederson WC, et al (eds): Green's Operative Hand Surgery, ed 5. Philadelphia, PA, Elsevier, 2005, p 281.

Question 11

Figures 9a and 9b show the radiographs of a 4-year-old child who sustained an elbow injury. What is the most likely complication resulting from this fracture if treated in a cast?

Explanation

The radiographs show a lateral condyle fracture with 2 mm of displacement. As opposed to other pediatric elbow fractures, lateral condyle fractures have a higher incidence of nonunion. This may be due to minimal metaphyseal bone on the distal fragment, the intra-articular nature of the fracture, or from further displacement when treated nonsurgically. These fractures with 2 mm and greater of displacement should be treated with reduction and stabilization. Osteonecrosis and fishtail deformity may be seen in very rare cases of lateral condyle fractures. The incidence is certainly less than the rates of nonunion seen in nonsurgically treated fractures with 2 mm and greater of displacement. Varus malunion from overgrowth and elbow stiffness are more likely seen in fractures treated surgically. Pirker ME, Weinberg AM, Hollwarth ME, et al: Subsequent displacement of initially nondisplaced and minimally displaced fractures of the lateral humeral condyle in children. J Trauma 2005;58:1202-1207. Finnbogason T, Karlsson G, Lindberg L, et al: Nondisplaced and minimally displaced fractures of the lateral humeral condyle in children: A prospective radiographic investigation of fracture stability. J Pediatr Orthop 1995;15:422-425.

Question 12

Which of the following is most commonly associated with an open clavicular fracture?

Explanation

Open clavicular fractures are rare and result from high-energy trauma. In a series of 20 patients with open clavicular fractures, 13 (65%) sustained a closed head injury. Fifteen (75%) had associated pulmonary injuries and 35% had a cervical or thoracic spine fracture. Only one demonstrated scapulothoracic dissociation. Screening for pulmonary and closed head injuries should be considered in the setting of traumatic open clavicular fractures.

Question 13

A 22-year-old woman injures her neck in a motor vehicle accident. Examination reveals no sensory or motor function below T8. Radiographs and an MRI scan show a burst fracture at T7. Forty-eight hours later, the bulbocavernosus reflex is present but there is no evidence of motor or sensory recovery in the lower extremities. What is the most likely diagnosis?

Explanation

Spinal shock typically ends after 48 hours with the return of reflexes, including the bulbocavernosus reflex. Lack of motor or sensory recovery in the lower extremities with the return of reflexes generally indicates a complete cord syndrome. Spivak JM, Connolly PJ (eds): Orthopaedic Knowledge Update: Spine 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, pp 179-187.

Question 14

A 26-year-old man falls off a motorcycle and injures his left wrist. There are no open wounds and the neurovascular examination is normal. Radiographs are shown in Figures 10a and 10b. Definitive management should consist of

Explanation

The patient has a high-energy injury with resultant comminution of the distal radius metaphysis. Cast immobilization is likely to lead to radial shortening and angulation due to the comminution. Similarly, while external fixation and pinning has been successful in the past, some loss of radial length and volar angulation is typically noted. Present plate fixation devices for the distal radius employing locking screw technology have a superior ability to resist radial shortening and dorsal angulation. Fixation of the ulnar styloid is warranted when there is distal radioulnar joint instability or significant displacement of the styloid. This is more likely to occur with a fracture at the base of the styloid. In this instance, the distal radioulnar joint does not appear to be disrupted. May MM, Lawton JN, Blazar PE: Ulnar styloid fractures associated with distal radius fractures: Incidence and implications for distal radioulnar joint instability. J Hand Surg Am 2002;27:965-971.

Question 15

Which of the following studies best increases the ability to diagnose femoral neck fractures in patients with femoral shaft fractures?

Explanation

Tornetta and associates and Yang and associates found that nearly half of all femoral neck fractures associated with femoral shaft fractures were being missed at their institution. On the basis of the delayed diagnosis of these injuries, a best-practice protocol was developed by the attending trauma surgeons for the evaluation of the femoral neck in patients with a femoral shaft fracture. This protocol includes a preoperative AP internal rotation radiograph of the hip, a fine-cut (2-mm) CT scan through the femoral neck (as a part of the initial trauma scan), and an intraoperative fluoroscopic lateral evaluation of the hip just prior to fixation of the femoral shaft. In addition, postoperative AP and lateral radiographs of the hip are made in the operating room to specifically evaluate the femoral neck before the patient is awakened. They found that fine-cut CT (2 mm was the best screening tool in this group of patients) identified 12 of the 13 fractures, whereas 8 of the 13 fractures were visible on the dedicated preoperative AP internal rotation hip radiographs. Tornetta P III, Kain MS, Creevy WR: Diagnosis of femoral neck fractures in patients with a femoral shaft fracture: Improvement with a standard protocol. J Bone Joint Surg Am 2007;89:39-43.

Question 16

The axis of forearm rotation occurs between what two anatomic points?

Explanation

Forearm rotation results from a complex interaction of osseous articulations and soft tissues including the radiocapitellar articulation, proximal and distal radioulnar joints, the interosseous membrane, and the adjacent forearm muscles. The rotation occurs around a longitudinal forearm axis extending from the center of the radial head proximally through the foveal region of the ulnar head distally. Werner FW, An KN: Biomechanics of the elbow and forearm. Hand Clin 1994;10:357-373.

Question 17

Figure 11 shows the radiograph of a 26-year-old man with type I diabetes mellitus who was struck by a motor vehicle. What is the most common complication associated with this pelvic fracture?

Explanation

The most common complication following acetabular or pelvic ring injury is deep venous thrombosis (DVT). Without prophylaxis, rates of DVT are as high as 70% to 80%. With prophylaxis, the rates are around 10%. Infection rates in surgical repair of acetabular fractures are relatively low but a history of diabetes mellitus and a significant Morel-Lavalle lesion certainly increase the risk. However, even with these two complicating factors, the rates of infection are still lower than 10%. Sciatic nerve palsy rates from the injury alone approach 20% and iatrogenic injury is usually less than 2%. Degenerative changes to the hip following this injury approach 20% to 25%, even with an anatomic reduction. Geerts WH, Code KI, Jay RM, et al: A prospective study of venous thromboembolism after major trauma. N Engl J Med 1994;331:1601-1606.

Question 18

Which of the following factors is a significant predictor of reoperation following open reduction and internal fixation of intertrochanteric fractures with a sliding-compression hip-screw device?

Explanation

As shown by Palm and associates from the Hip Fracture Study group, the integrity of the lateral femoral cortex in intertrochanteric hip fractures is a significant predictor of reoperation. Baumgartner and associates have shown that a tip-apex distance of greater than 25 mm is associated with a high risk of femoral head cut-out. Lastly, intertrochanteric hip fractures can be described as standard obliquity or reverse obliquity when describing the fracture pattern. Mechanistically, a reverse obliquity pattern is important to recognize because it reflects the presence or absence of a lateral buttress to which the proximal fracture fragment may compress. Palm H, Jacobsen S, Sonne-Holm S, et al: Integrity of the lateral femoral wall in intertrochanteric hip fractures: An important predictor of a reoperation. J Bone Joint Surg Am 2007;89:470-475. Sadowski C, Lübbeke A, Saudan M, et al: Treatment of reverse oblique and transverse intertrochanteric fractures with use of an intramedullary nail or a 95 degrees screw-plate: A prospective, randomized study. J Bone Joint Surg Am 2002;84:372-381.

Question 19

Following fixation of a displaced intra-articular fracture of the distal humerus through a posterior approach, what is the expected outcome?

Explanation

Following repair of a displaced intra-articular distal humerus fracture, the ability to regain full elbow range of motion is rare. Recent reports of olecranon osteotomy have yielded healing rates of between 95% to 100%. According to McKee and associates, patients can be expected to have residual loss of elbow flexion strength of 25%. McKee MD, Wilson TL, Winston L, et al: Functional outcome following surgical treatment of intra-articular distal humeral fractures through a posterior approach. J Bone Joint Surg Am 2000;82:1701-1707.

Question 20

A 15-year-old boy falls from his bicycle and sustains an injury to his elbow. Prereduction radiographs are shown in Figure 12a. Closed reduction is performed without difficulty and postreduction radiographs are shown in Figure 12b. What is the next most appropriate step in treatment?

Explanation

Elbow dislocations in children are rare injuries and usually result from a fall on an outstretched arm. The incidence of these injuries increases as patients age and concurrently the incidence of supracondylar humerus fractures decreases. In adolescent patients, simple elbow dislocations are treated with splint immobilization and the initiation of physical therapy once comfortable. The practitioner must be aware of structures that may get caught in the joint on reduction. These include the median nerve as well as the medial epicondyle. In this patient, the radiographs reveal a medial epicondyle fracture. Postreduction radiographs show the joint to be incongruous secondary to intra-articular displacement. At this point, the most appropriate treatment is to perform an open reduction and repair of the medial epicondyle fragment. Rasool MN: Dislocations of the elbow in children. J Bone Joint Surg Br 2004;86:1050-1058.

Question 21

A 7-year-old boy is seen in the emergency department with an isolated and displaced supracondylar humerus fracture and absent radial and ulnar pulses. Despite a moderately painful attempt at realignment, examination reveals that his hand remains pulseless. What is the next most appropriate step in management?

Explanation

Displaced supracondylar humerus fractures in children may have associated vascular compromise. Decreased blood flow may be due to vessel injury, entrapment within the fracture site, kinking from fracture displacement, or from vessel spasm. Optimal initial treatment in the emergency department includes gentle realignment of the limb and vascular assessment. Angiography is not required in isolated injuries as the level of the vessel compromise is always at the site of the fracture. When blood flow is not restored, the next best step in treatment is to proceed urgently to the operating room. A formal closed reduction and pinning is performed, and then the vascular status is reassessed. Exploration and vascular repair is required if the hand is cool, white, and without pulses. Ay S, Akinci M, Kamiloglu S, et al: Open reduction of displaced pediatric supracondylar humeral fractures through the anterior cubital approach. J Pediatr Orthop 2005;25:149-153. Sabharwal S, Tredwell SJ, Beauchamp RD, et al: Management of pulseless pink hand in pediatric supracondylar fractures of humerus. J Pediatr Orthop 1997;17:303-310.

Question 22

A 28-year-old cowgirl was injured while herding cattle 1 week ago. A radiograph and CT scans are shown in Figures 13a through 13c. What is the most appropriate management for this injury?

Explanation

The patient has an AP I pelvic ring disruption with minimal symphyseal widening. The best treatment is nonsurgical management and weight bearing as tolerated. This will help close the anterior pelvic ring during the healing process. Pelvic binders are excellent for acute treatment of widely displaced pelvic fractures but are not recommended for long-term use. Open reduction and internal fixation is not indicated for this injury and furthermore, the posterior ring is not injured. Matta JM: Indications for anterior fixation of pelvic fractures. Clin Orthop Relat Res 1996;329:88-96. Templeman DC, Schmidt AH, Sems SA, et al: Diastasis of the symphysis pubis: Open reduction internal fixation, in Wiss D (ed): Masters Techniques in Orthopaedic Surgery-Fractures, ed 2. Philadelphia, PA, Lippincott Williams and Wilkins, 2006, pp 639-648.

Question 23

As reflected by the SF-36 scores, patients with which of the following conditions demonstrate the most disability in physical function?

Explanation

Pollak and associates found that the average SF-36 score for patients who sustained a pilon fracture was significantly lower than patients with diabetes mellitus, AIDS, hypertension, asthma, migraines, pelvic fracture, polytrauma, and AMI. Moreover, patients having undergone pilon fixation scored lower on all but three of the SF-36 scales (vitality, mental health, and emotional health).

Question 24

A 25-year-old man is involved in a motor vehicle accident and brought to the emergency department at 4 am on Sunday morning. He has a closed distal third femoral shaft fracture. His leg is initially pulseless but after applying inline traction, a distal pulse can be palpated and the limb appears to be viable. The pulse in the injured limb "feels" different than the pulse in the uninjured limb. What is the next step in assessing the vascular status of this limb?

Explanation

The patient initially has a distal third femoral fracture and a pulseless limb. The first step is to reduce the fracture and reassess the vascular status. Although the pulse returns, it feels different than the quality of the pulse in the contralateral uninjured extremity. There is a risk of a vascular injury with this fracture pattern due to tethering of the femoral vessels at the adductor hiatus; therefore, the vascular status needs further assessment since the pulses are not symmetrical. A physical examination is not very accurate in assessing whether a vascular injury is present; therefore, serial examinations are not appropriate. Angiography is very sensitive and specific but is time consuming and can cause complications secondary to the dye and the arterial puncture required to perform it. Duplex ultrasound is effective but is very operator-dependent and may not be available 24 hours a day. The ABI is easily performed and has been shown to be sensitive and specific. If the value is greater than 0.9, the negative predictive value is 99% and when the value is less than 0.9, it is 95% sensitive and 97% specific for a major arterial injury. It has been shown to be useful for blunt lower extremity injuries as well as knee dislocations. Levy BA, Zlowodzki MP, Graves M, et al: Screening for extremity arterial injury with the arterial pressure index. Am J Emerg Med 2005;23:689-695. Abou-Sayed H, Berger DL: Blunt lower-extremity trauma and politeal artery injuries: Revisiting the case for selective arteriography. Arch Surg 2002;137:585-589.

Question 25

What is the most appropriate treatment for a 50-year-old woman who sustains the injury shown in Figures 14a and 14b?

Explanation

This intra-articular distal humerus fracture with displacement at the joint surface is best treated with surgical fixation. The most biomechanically sound construct is two plates applied to either column 180 degrees from one another. Elbow arthroplasty is most appropriate for low demand elderly patients. Schemitsch EH, Tencer AF, Henley MB: Biomechanical evaluation of methods of internal fixation of the distal humerus. J Orthop Trauma 1994;8:468-475. McCarty LP, Ring D, Jupiter JB: Management of distal humerus fractures. Am J Orthop 2005;34:430-438.

Question 26

A 35-year-old male is brought to the ED after a motorcycle crash. His blood pressure is 80/40 mmHg and heart rate is 120 bpm. Primary survey reveals an unstable pelvis. A pelvic binder is applied. Which of the following is the most appropriate anatomical landmark for the correct placement of a pelvic binder to optimize reduction and control hemorrhage?

Explanation

Pelvic binders should be placed centered over the greater trochanters to effectively close the pelvic volume and stabilize the pelvic ring. Placement over the iliac crests is a common error and fails to adequately close the symphysis.

Question 27

A 35-year-old hypotensive male is brought to the emergency department after a motorcycle collision. Radiographs demonstrate an 'open-book' pelvic ring injury. In the trauma bay, a circumferential pelvic binder is applied. To most effectively reduce the pelvic volume and stabilize the fracture, the binder should be centered over which of the following anatomic landmarks?

Explanation

Pelvic binders are most effective in reducing pelvic volume when centered directly over the greater trochanters. Placement over the iliac crests is less effective and may inadvertently increase the pelvic volume or exacerbate the deformity.

Question 28

A 40-year-old farmer sustains a Gustilo-Anderson Grade IIIB open tibial shaft fracture with severe soil and fecal contamination following a tractor rollover. According to current orthopedic trauma guidelines, what is the most appropriate initial prophylactic antibiotic regimen?

Explanation

For Grade III open fractures with severe organic/agricultural contamination, guidelines recommend a first-generation cephalosporin, an aminoglycoside for gram-negative coverage, and penicillin to cover anaerobic organisms such as Clostridium species.

Question 29

A 25-year-old male is admitted with a highly comminuted tibial shaft fracture. Twelve hours later, he complains of severe leg pain out of proportion to the injury, unrelieved by opioids. Passive stretch of the toes exacerbates the pain. Which of the following pressure measurements is the most reliable threshold for diagnosing acute compartment syndrome?

Explanation

A 'delta pressure' (diastolic blood pressure minus the measured compartment pressure) of less than 30 mmHg is considered the most reliable objective diagnostic threshold for acute compartment syndrome.

Question 30

A 28-year-old woman sustains a displaced femoral neck fracture. Which of the following factors has been shown in the literature to be the most significant predictor for the development of avascular necrosis (AVN) of the femoral head in young adults?

Explanation

The initial magnitude of fracture displacement is the most critical predictor for the development of AVN in young patients with femoral neck fractures. While early fixation is recommended, recent literature suggests time to surgery has less impact on AVN rates than the initial traumatic insult.

Question 31

A polytrauma patient presents with bilateral closed femur fractures, a severe closed head injury, and bilateral pulmonary contusions. On admission, arterial blood gas reveals a base deficit of 9 mEq/L and a lactate of 4.5 mmol/L. What is the most appropriate initial management of the femur fractures?

Explanation

This patient is 'borderline' or 'in extremis' based on the severe base deficit, elevated lactate, head injury, and pulmonary contusions. Damage control orthopedics (DCO) using bilateral external fixation minimizes the systemic 'second hit' of prolonged surgery and reaming.

Question 32

According to the Lower Extremity Assessment Project (LEAP) study, which of the following scoring systems most accurately predicts the functional outcome and need for amputation in a patient with a mangled lower extremity?

Explanation

The LEAP study demonstrated that none of the existing limb salvage scoring systems (including MESS, LSI, NISSSI, and PSI) are highly predictive of the ultimate need for amputation or the final functional outcome.

Question 33

A 45-year-old man sustains a severe pelvic crush injury. Clinical examination reveals a large, fluctuant, soft-tissue mass overlying the greater trochanter. What is the pathophysiology of this specific soft-tissue injury?

Explanation

A Morel-Lavallee lesion is a closed degloving injury caused by severe shearing forces that separate the skin and subcutaneous fat from the underlying fascial layer, creating a potential space that fills with blood and lymphatic fluid.

Question 34

A 50-year-old male undergoes a dual-incision four-compartment fasciotomy for acute compartment syndrome associated with a Schatzker VI tibial plateau fracture. Despite the procedure, he continues to have progressive ischemic pain and toe flexion contractures. Incomplete release of which compartment is the most likely cause of his ongoing symptoms?

Explanation

The deep posterior compartment is the most commonly missed or incompletely released compartment during a lower leg fasciotomy. This is often due to an inadequate surgical release of the fascial attachments of the soleus bridge.

Question 35

A 60-year-old woman presents to the emergency department after a fall onto an outstretched hand, sustaining a severely displaced, apex volar distal radius fracture. She complains of dense numbness in her thumb, index, and long fingers, and severe pain. What is the most appropriate next step in management?

Explanation

The initial management of acute median nerve neuropathy associated with a displaced distal radius fracture is prompt closed reduction and splinting in a neutral position. If symptoms fail to improve or worsen after reduction, surgical decompression is indicated.

Question 36

A 32-year-old man is brought to the emergency department after a high-speed motor vehicle collision. Imaging reveals a traumatic spondylolisthesis of the axis (Hangman's fracture) with bilateral pars interarticularis fractures. Which of the following is the classic mechanism of injury for this fracture pattern?

Explanation

A Hangman's fracture (traumatic spondylolisthesis of C2) is classically caused by a combination of hyperextension and axial loading forces, leading to fractures through the bilateral pars interarticularis.

Question 37

A 6-year-old boy presents with a Gartland type III extension-type supracondylar humerus fracture. On examination, the radial pulse is absent, but the hand is warm and pink with brisk capillary refill. What is the most appropriate next step in management?

Explanation

A 'pulseless but pink' (well-perfused) hand following a displaced pediatric supracondylar humerus fracture indicates adequate collateral circulation. The initial treatment is urgent closed reduction and pinning to relieve pressure on the brachial artery.

Question 38

A 65-year-old woman on long-term alendronate therapy presents with prodromal thigh pain followed by a low-energy transverse fracture of the femoral shaft. Radiographs show lateral cortical thickening at the fracture site. What is the primary pathophysiologic mechanism leading to this atypical fracture?

Explanation

Long-term bisphosphonate use suppresses targeted osteoclastic bone remodeling. This impairs the normal repair of daily microdamage, leading to an accumulation of microcracks, increased bone brittleness, and eventually an atypical femur fracture.

Question 39

A 40-year-old male sustains an APC-III (Anteroposterior Compression type III) pelvic ring injury and is profoundly hypotensive. In the setting of severe pelvic trauma, which of the following is statistically the most common source of major pelvic hemorrhage?

Explanation

Although arterial bleeding can be catastrophic and require embolization, approximately 80-90% of significant pelvic hemorrhage originates from the presacral venous plexus and exposed cancellous bone surfaces.

Question 40

According to the Lauge-Hansen classification, what is the sequential order of anatomic structures injured in a Supination-External Rotation (SER) ankle fracture?

Explanation

The SER sequence progresses anterolaterally to posteromedially: Stage 1 is AITFL rupture; Stage 2 is an oblique/spiral distal fibula fracture; Stage 3 is PITFL rupture or posterior malleolus fracture; Stage 4 is a medial malleolus fracture or deltoid ligament rupture.

Question 41

A 22-year-old unrestrained passenger presents after a head-on motor vehicle collision with severe hip pain. Radiographs demonstrate a posterior dislocation of the hip without an associated fracture. In what position is the injured lower extremity classically held upon clinical presentation?

Explanation

Patients with a posterior hip dislocation classically present with the affected lower extremity in a flexed, adducted, and internally rotated position. Conversely, anterior dislocations typically present externally rotated and abducted.

Question 42

A 35-year-old male falls from a ladder and sustains a 'terrible triad' injury of the elbow. Operative management is planned. According to standard principles of surgical reconstruction for this specific injury, what is the recommended sequence of repair?

Explanation

The standard surgical approach to a terrible triad injury proceeds from deep to superficial. The recommended sequence is stabilization of the coronoid (or anterior capsule), followed by radial head repair or replacement, and finally repair of the LUCL complex.

Question 43

A 25-year-old competitive cyclist falls directly onto his shoulder and sustains a closed, isolated midshaft clavicle fracture. Which of the following radiographic findings represents the strongest indication for operative fixation (ORIF) over nonoperative management?

Explanation

A midshaft clavicle fracture with complete (100%) displacement and shortening greater than 2 cm is strongly associated with higher rates of nonunion, symptomatic malunion, and poorer functional outcomes if treated nonoperatively.

Question 44

A 30-year-old man sustains a low-velocity civilian gunshot wound to the thigh, resulting in a comminuted midshaft femur fracture. The bullet passed cleanly through the soft tissues without massive tissue destruction. His distal pulses are intact. What is the standard of care for the management of this fracture?

Explanation

Low-velocity civilian gunshot fractures of the femur without significant soft tissue devitalization or vascular injury can be safely treated with early intramedullary nailing. Routine formal debridement of the bullet track is not required.

Question 45

A 40-year-old man sustained a Hawkins Type II talar neck fracture and underwent open reduction and internal fixation. At his 8-week follow-up, an AP radiograph of the ankle reveals 'Hawkins sign'. What does this radiographic finding indicate?

Explanation

Hawkins sign is a subchondral radiolucent band visible in the talar dome 6 to 8 weeks post-injury. It represents subchondral atrophy due to bone resorption, which requires an intact blood supply, thereby indicating a good prognosis against AVN.

Question 46

A hemodynamically unstable trauma patient presents with an anterior-posterior compression (APC) type III pelvic ring injury. The trauma team decides to apply a noninvasive pelvic binder. What is the correct anatomical landmark for placing the center of the binder to optimally reduce pelvic volume?

Explanation

A pelvic binder should be centered over the greater trochanters to effectively compress the pelvic ring and reduce volume in open-book injuries. Placement over the iliac crests is incorrect as it can paradoxically widen the pubic symphysis.

Question 47

A 28-year-old female sustains a Gustilo-Anderson type IIIB open tibia fracture. She has a documented history of anaphylaxis to penicillin. Which of the following intravenous antibiotic regimens is most appropriate in the emergency department?

Explanation

For type III open fractures, gram-positive and gram-negative coverage is required. In patients with a severe penicillin allergy (anaphylaxis), clindamycin or vancomycin should replace a first-generation cephalosporin, combined with an aminoglycoside or fluoroquinolone.

Question 48

A 30-year-old man sustains a closed tibial shaft fracture. His blood pressure in the emergency department is 120/80 mm Hg. Compartment pressures are measured as follows: Anterior 45 mm Hg, Lateral 35 mm Hg, Superficial Posterior 40 mm Hg, Deep Posterior 50 mm Hg. What is the Delta P and the most appropriate next step?

Explanation

Delta P is calculated as the diastolic blood pressure minus the highest compartment pressure (80 - 50 = 30 mm Hg). A Delta P of 30 mm Hg or less indicates inadequate capillary perfusion pressure and is an absolute indication for emergency fasciotomy.

Question 49

A 25-year-old male sustains bilateral femoral shaft fractures in a motor vehicle collision. On post-injury day two, he develops acute respiratory distress. Which of the following represents the classic clinical triad of fat embolism syndrome?

Explanation

The classic clinical triad of fat embolism syndrome consists of hypoxemia, neurologic abnormalities (such as confusion or altered mental status), and a petechial rash. It typically presents 24 to 72 hours after severe long bone fractures.

Question 50

In the context of Damage Control Orthopedics (DCO) for a polytraumatized patient, which of the following metabolic parameters best indicates adequate systemic resuscitation, allowing safe conversion from external fixation to definitive intramedullary nailing?

Explanation

Normalization of serum lactate (less than 2.5 mmol/L) and base deficit are the most reliable indicators of adequate tissue perfusion and systemic resuscitation. This normalization implies the patient is physiologically optimized for definitive long surgical procedures.

Question 51

A 40-year-old man presents with a high-energy posterior knee dislocation. After closed reduction, pedal pulses are palpable but appear asymmetric compared to the uninjured limb. What is the most appropriate next step in evaluation?

Explanation

Following reduction of a knee dislocation, if pulses are present but diminished or asymmetric, ABI should be measured. An ABI of less than 0.9 warrants immediate advanced vascular imaging (such as CTA) or surgical consultation.

Question 52

A 28-year-old trauma patient has an estimated blood loss of 35%. His vitals show a blood pressure of 90/60 mm Hg, heart rate of 130 bpm, and respiratory rate of 30 breaths/min. He is confused and his urine output is 10 mL/hr. According to the ATLS classification, what class of hemorrhagic shock does this represent?

Explanation

Class III hemorrhagic shock represents 30-40% blood volume loss. It is classically characterized by hypotension, marked tachycardia (HR > 120), tachypnea, decreased urine output, and a change in mental status.

Question 53

A 35-year-old male sustains a Gustilo-Anderson type II open tibial shaft fracture. Intravenous antibiotics are administered within 30 minutes of arrival. Due to operating room unavailability, surgical debridement is delayed for 10 hours. How does this delay affect his infection risk compared to debridement within 6 hours?

Explanation

Recent literature demonstrates that early administration of appropriate intravenous antibiotics is the most critical factor in preventing infection. Delaying surgical debridement up to 24 hours in low-grade open fractures does not significantly increase infection rates if antibiotics were given promptly.

Question 54

A 22-year-old man presents with a low-velocity civilian gunshot wound to the thigh resulting in a midshaft femur fracture. Vascular examination is normal, with symmetric pulses and an Ankle-Brachial Index (ABI) of 1.1. What is the most appropriate initial management?

Explanation

Low-velocity gunshot wounds resulting in fractures with a normal vascular examination (ABI > 0.9) do not require routine angiography or immediate operative debridement of the tracts. They are treated with local wound care, tetanus prophylaxis, and appropriate fracture stabilization.

Question 55

A 34-year-old polytrauma patient presents with a severe closed head injury (GCS 7) and bilateral femoral shaft fractures. Intracranial pressure (ICP) monitoring reveals an ICP of 25 mm Hg. What is the safest initial orthopedic management for the femur fractures?

Explanation

In patients with severe traumatic brain injury and elevated intracranial pressure, prolonged physiological insults from reaming and definitive fixation can cause a 'second hit' exacerbating secondary brain injury. Damage control orthopedics with rapid external fixation is indicated.

Question 56

The CRASH-2 trial demonstrated a significant mortality benefit for the use of tranexamic acid (TXA) in bleeding trauma patients. What is the mechanism of action and the optimal timing of administration for TXA?

Explanation

Tranexamic acid (TXA) is an antifibrinolytic that competitively inhibits the activation of plasminogen to plasmin. The CRASH-2 trial showed improved survival in bleeding trauma patients when TXA is administered within 3 hours of injury.

Question 57

In the evaluation of a mangled lower extremity, which of the following is considered an absolute indication for primary amputation?

Explanation

Absolute indications for primary amputation are rare but include anatomically complete transection of the limb or an unreconstructible vascular injury resulting in irreversible warm ischemia. Nerve injury and high MESS scores are relative indications.

Question 58

Acute compartment syndrome of the thigh is a rare but devastating complication typically associated with severe blunt trauma or femur fractures. Which compartment of the thigh is most frequently involved?

Explanation

The anterior compartment of the thigh is the most commonly involved compartment in thigh compartment syndrome. It contains the quadriceps muscle group and the femoral nerve.

Question 59

A hemodynamically unstable patient with an anterior-posterior compression (APC) type III pelvic ring injury transiently responds to fluid resuscitation. A pelvic binder has been appropriately placed, but the patient's blood pressure begins to drop again. FAST exam is negative. What is the most appropriate next step in management?

Explanation

In a hemodynamically unstable pelvic fracture patient with a negative FAST exam (ruling out massive intra-abdominal hemorrhage), the bleeding is likely retroperitoneal. Preperitoneal pelvic packing or angioembolization is the standard of care to achieve hemostasis.

Question 60

A 25-year-old male sustains a displaced intracapsular femoral neck fracture from a fall off a ladder. What is the most appropriate timing and goal of surgical intervention?

Explanation

Femoral neck fractures in young adults are high-energy injuries considered orthopedic emergencies. Urgent open reduction and internal fixation (typically within 24 hours) is recommended to decompress the intracapsular hematoma and minimize the high risks of avascular necrosis and nonunion.

Question 61

A 35-year-old male is admitted with a closed tibial shaft fracture following a motor vehicle collision. He is intubated for an associated head injury. Intracompartmental pressure monitoring is initiated. Which of the following thresholds is the most widely accepted absolute indication for a four-compartment fasciotomy?

Explanation

A Delta P (diastolic blood pressure minus compartment pressure) of less than 30 mmHg is the most reliable threshold for diagnosing acute compartment syndrome. Absolute pressure alone is less accurate, especially in hypotensive trauma patients.

Question 62

A 45-year-old male presents in hemorrhagic shock following a motorcycle collision. An anteroposterior pelvic radiograph demonstrates a symphyseal diastasis of 4 cm. What is the most appropriate anatomic landmark for the placement of a circumferential pelvic sheet or commercial binder to ensure optimal mechanical reduction?

Explanation

Pelvic binders should be centered over the greater trochanters to effectively close an anterior ring disruption. Placement over the iliac crests is less mechanically efficient and can inadvertently worsen the displacement.

Question 63

A 28-year-old female sustains a Grade IIIb open tibial shaft fracture with heavy farm soil contamination. According to current evidence-based guidelines, what is the most appropriate initial intravenous antibiotic regimen to administer in the emergency department?

Explanation

For severe open fractures with heavy contamination (e.g., farm injuries), a first-generation cephalosporin, an aminoglycoside, and penicillin are recommended to cover Gram-positive, Gram-negative, and anaerobic organisms. Early administration is critical in reducing infection rates.

Question 64

A 22-year-old male sustains a closed femoral shaft fracture and severe bilateral pulmonary contusions. Which of the following physiologic parameters strongly suggests that Damage Control Orthopedics (DCO) via external fixation is favored over Early Total Care (ETC) with intramedullary nailing?

Explanation

Damage Control Orthopedics (DCO) is indicated in borderline or unstable polytrauma patients. Indicators of inadequate resuscitation and high risk for "second hit" complications include an arterial lactate > 4.0 mmol/L, base deficit > 6.0 mEq/L, and severe lung injury.

Question 65

A 30-year-old male sustains a completely displaced transcervical femoral neck fracture following a fall from height. To minimize the risk of avascular necrosis (AVN), what is the optimal surgical timing and management of this injury?

Explanation

Femoral neck fractures in young adults are considered relative orthopedic emergencies. Urgent anatomic reduction and stable internal fixation (typically within 24 hours) is critical to preserve the native hip and reduce the incidence of AVN.

Question 66

A 55-year-old female undergoes volar locking plate fixation for a displaced distal radius fracture. Six months postoperatively, she presents with an inability to actively flex the interphalangeal joint of her thumb. Which of the following technical errors most likely contributed to this complication?

Explanation

Placement of a volar plate distal to the watershed line of the distal radius risks hardware prominence against the flexor pollicis longus (FPL) tendon. This constant friction can lead to delayed FPL rupture.

Question 67

A 40-year-old male sustains a Grade IIIa open tibia fracture. He receives appropriate intravenous antibiotics and tetanus prophylaxis in the emergency department. Based on current literature, what is the single most critical factor in decreasing his risk of deep infection?

Explanation

The early administration of systemic antibiotics (ideally within 1 to 3 hours of injury) is the most critical factor in decreasing the rate of infection in open fractures. Thorough surgical debridement is also essential.

Question 68

A 25-year-old male presents with a gunshot wound to the right distal thigh, an expanding hematoma, and an absent dorsalis pedis pulse. Radiographs reveal a comminuted distal femur fracture. What is the most appropriate sequence of operative management?

Explanation

In the setting of a complex mangled extremity with profound ischemia, temporary vascular shunting is typically performed first to restore perfusion. This is followed by rapid skeletal stabilization (e.g., external fixation) and then definitive vascular repair.

Question 69

A 29-year-old male sustains a posterior hip dislocation. Closed reduction is performed within 4 hours. A post-reduction CT scan demonstrates a 5 mm intra-articular bone fragment and an incongruent hip joint. What is the next most appropriate step in management?

Explanation

An incongruent joint following hip reduction, especially with a retained intra-articular fragment, is an absolute indication for surgical exploration. Failure to remove the fragment leads to rapid articular cartilage destruction.

Question 70

A 35-year-old man sustains a closed tibial shaft fracture in a motor vehicle collision. Six hours after admission, he complains of severe, unrelenting leg pain that is poorly controlled with intravenous narcotics. His leg is tense and markedly swollen. Blood pressure is 110/70 mm Hg. A compartment pressure monitor reveals an absolute anterior compartment pressure of 45 mm Hg. What is the most appropriate next step in management?

Explanation

The patient has acute compartment syndrome. A Delta P (diastolic blood pressure minus compartment pressure) of less than 30 mm Hg (70 - 45 = 25 mm Hg) is an absolute indication for immediate fasciotomy.

Question 71

A 40-year-old man is brought to the trauma bay after a high-speed motorcycle crash. He has an anteroposterior compression (APC) type III pelvic ring injury. His initial blood pressure is 80/40 mm Hg. A pelvic binder is applied correctly, but he remains hypotensive despite initial blood transfusion. Focused assessment with sonography for trauma (FAST) is negative. What is the next most appropriate step?

Explanation

In a hemodynamically unstable patient with a pelvic ring injury and a negative FAST exam, the bleeding is likely retroperitoneal from the pelvic fracture. Pre-peritoneal pelvic packing or pelvic angiography with embolization is the appropriate next step.

Question 72

A 28-year-old man sustains a closed distal third spiral fracture of the humerus (Holstein-Lewis fracture). On initial examination in the emergency department, his radial nerve function is intact. Following a closed reduction and application of a coaptation splint, he is unable to extend his wrist or fingers, and lacks sensation in the first dorsal web space. What is the most appropriate management?

Explanation

Loss of radial nerve function following closed reduction of a humeral shaft fracture suggests nerve entrapment within the fracture site. This is an absolute indication for immediate surgical exploration.

Question 73

A 25-year-old woman is brought to the emergency department after a severe traumatic knee dislocation. The knee is successfully reduced. Dorsalis pedis and posterior tibial pulses are palpable but slightly weaker than the contralateral limb. An Ankle-Brachial Index (ABI) is measured at 0.85. What is the most appropriate next step in management?

Explanation

An ABI less than 0.9 in the setting of a knee dislocation is highly suspicious for a popliteal artery injury. A CT angiogram is indicated to evaluate for an intimal tear or flow-limiting vascular lesion.

Question 74

A 32-year-old farmer sustains an open fracture of the left tibia after being pinned by a tractor in a muddy field. The wound is 12 cm long with extensive soft tissue stripping and visible bone, but vascularity is intact. Which of the following intravenous antibiotic regimens is most appropriate in the emergency setting?

Explanation

This is a Gustilo-Anderson Type IIIb fracture sustained in a highly contaminated agricultural environment. High-dose Penicillin is added to the standard Cefazolin and Aminoglycoside regimen to cover Clostridium species.

Question 75

An 82-year-old woman with a history of atrial fibrillation sustains an intertrochanteric femur fracture. She takes daily warfarin. Her initial INR in the emergency department is 3.5. Which of the following is the most appropriate method to rapidly reverse her coagulopathy for surgical fixation within 24 hours?

Explanation

The most rapid and reliable reversal of warfarin-induced coagulopathy for urgent orthopedic trauma surgery is achieved with Prothrombin Complex Concentrate (PCC) and Intravenous Vitamin K.

Question 76

A 22-year-old man is brought in after an ejection from a vehicle. He has bilateral closed femoral shaft fractures, a pulmonary contusion, and a Glasgow Coma Scale (GCS) of 7. His initial lactate is 4.5 mmol/L, and his pH is 7.15. Which of the following is the most appropriate initial orthopedic management of his femur fractures?

Explanation

This patient is physiologically unstable (acidosis, high lactate, head injury, pulmonary contusion). Damage Control Orthopedics (DCO) using temporary bilateral external fixation is indicated to minimize the second hit of surgical trauma.

Question 77

A 30-year-old man falls from a height and sustains a displaced, completely vertical (Pauwels type III) femoral neck fracture. To maximize biomechanical stability and minimize the risk of nonunion and avascular necrosis, what is the most appropriate surgical construct?

Explanation

In young patients with vertical, high-shear femoral neck fractures (Pauwels III), a fixed-angle construct like a sliding hip screw offers superior biomechanical stability against vertical shear forces compared to parallel cannulated screws.

Question 78

A 45-year-old snowboarder sustains a Hawkins Type II talar neck fracture. She undergoes open reduction and internal fixation. At her 8-week follow-up, an AP radiograph of the ankle demonstrates a subchondral radiolucent band in the dome of the talus. What is the clinical significance of this finding?

Explanation

This radiographic finding is Hawkins sign, which is subchondral osteopenia of the talar dome. It indicates that the talar body retains its blood supply and is undergoing normal disuse osteopenia, making avascular necrosis highly unlikely.

Question 79

A 50-year-old roofer falls 15 feet and sustains a displaced, intra-articular calcaneus fracture. It is treated with open reduction and internal fixation via a classic extensile lateral approach. Which of the following is the most common complication associated with this specific surgical approach?

Explanation

The extensile lateral approach to the calcaneus is notorious for soft tissue complications, with wound margin necrosis and dehiscence occurring in up to 10-25% of cases due to the precarious blood supply of the L-shaped flap.

Question 80

A 65-year-old woman on long-term oral bisphosphonate therapy presents with thigh pain and sustains a low-energy transverse fracture of the subtrochanteric femur. Radiographs reveal lateral cortical thickening and a transverse fracture with a medial spike. What is the most appropriate surgical management?

Explanation

Atypical bisphosphonate-related femur fractures require full-length intramedullary nailing to protect the entire femur, as the bone remodeling defect affects the whole diaphysis and places it at risk for future fractures.

Question 81

A 9-year-old boy falls off monkey bars and presents with forearm pain. Radiographs demonstrate a fracture of the proximal third of the ulna and an anterior dislocation of the radial head. Which nerve is most commonly injured in this specific fracture-dislocation pattern?

Explanation

This is a Monteggia fracture-dislocation. The radial head dislocation (especially anterior or lateral) can stretch or directly injure the Posterior Interosseous Nerve (PIN), leading to weakness in finger and thumb extension.

Question 82

A 27-year-old man is brought to the emergency room with a gunshot wound to the mid-thigh. Radiographs show a highly comminuted midshaft femur fracture with retained bullet fragments. The weapon was a low-velocity civilian handgun. The patient has no vascular deficits or expanding hematoma. What is the standard of care for this injury?

Explanation

Low-velocity gunshot wounds resulting in femur fractures without neurovascular compromise do not require formal operative debridement of the bullet tract. They are treated safely with superficial wound care, tetanus, antibiotics, and standard intramedullary nailing.

Question 83

A 45-year-old man sustains an ankle injury. Radiographs show a spiral fracture of the distal fibula above the level of the syndesmosis (Weber C). The medial clear space is widened to 6 mm. Which of the following structures is unequivocally torn in this injury pattern?

Explanation

A Weber C fracture with widening of the medial clear space indicates a completely unstable syndesmotic injury. The interosseous membrane is torn from the ankle joint up to the level of the fibula fracture.

Question 84

A 38-year-old woman is involved in an MVA. Radiographs and a CT scan of the knee reveal an isolated, displaced coronal plane fracture of the lateral femoral condyle. What is this fracture called, and which screw trajectory is biomechanically superior for its fixation?

Explanation

A coronal plane fracture of the femoral condyle is known as a Hoffa fracture. Biomechanical studies have demonstrated that posterior-to-anterior directed lag screws provide superior fixation and compression compared to anterior-to-posterior screws.

Question 85

When applying a commercial pelvic binder to a hypotensive trauma patient with a presumed open-book pelvic ring injury, what anatomic landmark should be used to center the device to ensure optimal mechanical closure of the pelvic volume?

Explanation

Pelvic binders must be centered directly over the greater trochanters to effectively compress the pelvic ring and reduce the retroperitoneal volume. Placement too high (e.g., over the iliac crests) is less effective and can worsen certain fracture patterns.

Question 86

A 22-year-old rugby player is tackled and sustains a traumatic posterior hip dislocation. Upon evaluation in the emergency department, what is the classic resting position of the affected lower extremity?

Explanation

A classic posterior hip dislocation presents with the affected limb shortened, adducted, and internally rotated. In contrast, an anterior hip dislocation typically presents with the limb abducted and externally rotated.

Question 87

A 55-year-old man presents with a highly comminuted Schatzker VI tibial plateau fracture. He is complaining of extreme pain. What is considered the most reliable and earliest clinical finding of acute compartment syndrome in a conscious patient?

Explanation

Pain out of proportion to the apparent injury and severe pain exacerbated by passive stretch of the compartments involved are the earliest and most sensitive clinical signs of acute compartment syndrome. Pulselessness and pallor are very late signs.

Question 88

A 70-year-old man falls and sustains an unstable odontoid fracture (Type II). Non-operative management with a halo vest is considered. Which of the following is an absolute contraindication to the use of a halo vest in an elderly patient?

Explanation

Halo vests restrict chest excursion and can severely compromise pulmonary mechanics. In elderly patients with severe respiratory disease, a halo vest is contraindicated due to the high risk of pneumonia and respiratory failure.

Question 89

A 45-year-old male falls from a ladder and sustains a high-energy distal tibia fracture.

He presents to the emergency department with massive soft tissue swelling and clear fracture blisters around the ankle. What is the most appropriate initial management to minimize soft tissue complications while providing adequate skeletal stability?

Explanation

For severe pilon fractures with significant soft tissue compromise (e.g., fracture blisters, massive swelling), the standard of care is a staged protocol. Initial management consists of a spanning external fixator to allow soft tissue recovery, followed by definitive internal fixation 1 to 3 weeks later.

Question 90

A 35-year-old male is brought to the trauma bay after a motorcycle collision. He is hypotensive and tachycardic. A pelvic radiograph demonstrates an anteroposterior compression (APC) III injury. The trauma team decides to apply a circumferential pelvic binder. To most effectively reduce the pelvic volume and stabilize the fracture, over which anatomic landmark should the binder be centered?

Explanation

Circumferential pelvic binders are most effective at reducing pelvic volume and stabilizing the pelvic ring when centered over the greater trochanters. Placement over the iliac crests is less effective and can inadvertently increase pelvic volume in certain fracture patterns.

Question 91

A 24-year-old male sustains an isolated Gustilo-Anderson type IIIB open tibial shaft fracture following a farming accident. According to current evidence-based guidelines, which of the following interventions is the most critical factor in reducing his risk of developing a deep-seated infection?

Explanation

Early administration of appropriate intravenous antibiotics is the single most important factor in reducing infection rates in open fractures. The traditional 6-hour rule for surgical debridement has not been strongly supported by modern evidence compared to the timing of antibiotic administration.

Question 92

A 42-year-old male presents with a severely displaced, closed midshaft tibia fracture. He is complaining of intense leg pain out of proportion to the apparent injury, and pain with passive stretch of the hallux. His blood pressure is 110/70 mmHg. Intracompartmental pressures are measured. Which of the following pressure readings definitively indicates the need for an emergent four-compartment fasciotomy?

Explanation

The most reliable physiological indicator for fasciotomy is the Delta P (diastolic blood pressure minus the absolute compartment pressure) being 30 mmHg or less. A compartment pressure of 45 mmHg and a diastolic BP of 70 mmHg yields a Delta P of 25 mmHg, definitively indicating emergent fasciotomy.

Orthopedic Surgery Board Prep: Set 403 (100 MCQs on Fractures & Casting)

AAOS Orthopedic Trauma MCQs (Set 1): Acute Fracture & Emergency Care | ABOS & OITE Review

Key Takeaway

AAOS Orthopedic Trauma MCQs (Set 1): Acute Fracture & Emergency Care | ABOS & OITE Review

Chapter Index