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2. Trauma MCQs

Practice Set 182 of 640

This practice set contains high-yield board review questions covering key concepts in 2. Trauma. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.

Question 3621

Topic: 2. Trauma

A 46-year-old man fell 20 feet and sustained the injury shown in Figure 3. The injury is closed; however, the soft tissues are swollen and ecchymotic with blisters. The most appropriate initial management should consist of

. a long leg cast.
. a short leg cast.
. immediate open reduction and internal fixation.
. a temporizing spanning external fixator.
. primary ankle fusion.

Correct Answer & Explanation

. a long leg cast.

Explanation

DISCUSSION: Although this is a fracture of the medial and lateral malleoli, the degree of displacement and comminution of the medial dome indicate that this injury is similar to a pilon fracture.  Initial management should consistent of stabilization to allow for soft-tissue healing.  The use of temporizing spanning external fixation should be the initial step, followed by limited or more extensive open reduction and internal fixation when the soft-tissue status will allow.  Initial placement in either a short or long leg cast does not provide the needed stability and does not allow for care and monitoring of soft tissues.  In addition, maintaining reduction of the talus may be very difficult.  Immediate open reduction and internal fixation through an injured soft-tissue envelope adds the risk of difficulties with incision healing and a higher risk of deep infection.  In the acute setting, a primary ankle fusion through this soft-tissue envelope isnot indicated.REFERENCES: Marsh JL, Bonar S, Nepola JV, et al: Use of an articulated external fixator for fractures of the tibial plafond.  J Bone Joint Surg Am 1995;77:1498-1509.Wyrsch B, McFerran MA, McAndrew M, et al: Operative treatment of fractures of the tibial plafond: A randomized, prospective study.  J Bone Joint Surg Am 1996;78:1646-1657.Thordarson DB: Complications after treatment of tibial pilon fractures: Prevention and management strategies.  J Am Acad Orthop Surg 2000;8:253-265.

Question 3622

Topic: 2. Trauma

A 52-year-old woman slipped on ice in her driveway. Radiographs are shown in Figures 19a and 19b. The patient was treated in a short leg cast with weight bearing as tolerated for 6 weeks. Due to persistent tenderness at the fracture site, a CAM walker was used for an additional 8 weeks. Nine months after the injury, the patient still walks with a limp and reports pain with deep palpation at the fracture site. What is the next most appropriate step in management? Review Topic

. CT scan
. Repeat period of immobilization
. Referral to pain management for sympathetic blocks
. Continued observation and physical therapy
. Acupuncture

Correct Answer & Explanation

. CT scan

Explanation

Persistent pain at the fracture site in the absence of infection is most likely due to a nonunion, best detected by CT. Walsh and DiGiovanni reported on a series of closed rotational fibular fractures in which nonunions were detected by CT in the absence of standard ankle radiographic findings. Repeat immobilization would not be appropriate at this late date. Pain management/sympathetic blocks would be considered if the patient displayed pain with light touch and disproportionate pain consistent with a complex mediated pain syndrome. Acupuncture would be expected to be of limited benefit.

Question 3623

Topic: 2. Trauma

A 36-year-old man sustains blunt chest trauma, an open right femur fracture, and a closed left tibia fracture following a high-speed MVC. Upon presentation to the emergency room, blood pressure is 80/40, HR 135, and urine output is .4 cc/kg/hr. Fluids and blood products are administered, and the patient is transferred to the ICU for further care. Which of the following indicates adequate resuscitation has been achieved?

. Systolic blood pressure > 120
. Heart rate between 60-100
. Urine output equals 0.4 cc/kg/hr
. Gastric intramucosal pH of 7.4
. Normal mentation

Correct Answer & Explanation

. Systolic blood pressure > 120

Explanation

DISCUSSION: Of the following variables, only a normal gastric mucosal pH (>7.3) is associated with restoration of tissue oxygenation.Shock is an abnormality of the circulatory system that results in inadequate organ perfusion and tissue oxygenation. This leads to anaerobic metabolism with the development of lactic acidosis and oxygen debt. Shock is either classified as compensated or uncompensated. Compensated shock exists when there is evidence of ongoing inadequate tissue perfusion despite the normalization of blood pressure, heart rate, and urine output. Uncompensated shock occurs when there is inadequate tissue perfusion and abnormal blood pressure, heart rate, and urine output. Thus, a patient may have normal vital signs but still be in a state of compensated shock that requires additional resuscitation.Porter et al. review the optimal end points of resuscitation in trauma patients. They conclude that using traditional end points such as blood pressure, urine output and heart rate, may leave up to 85% of patients in "compensated" shock. They urge the use of lactate, base deficit, and gastric intramucosal pH as appropriate end points of resuscitation.Roberts et al. discuss various aspects of damage control orthopaedics in the multiply injured trauma patient. Although they do not discuss the end points for resuscitation, they note that they presence of shock is a clinical parameter associated with adverse outcomes in the trauma patient.Incorrect answers:

Question 3624

Topic: 2. Trauma

Lateral 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 screws
. Increased rigidity
. Decreased need for delayed hardware removal
. Decreased peroneal irritation
. Improved distal fixation

Correct Answer & Explanation

. Decreased joint penetration of distal screws

Explanation

DISCUSSION: Posterior 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.

Question 3625

Topic: 2. Trauma

A 16-year-old high school football player sustains an injury to the left hip. The avulsed fragment identified by the arrow in Figure 34 represents the origin of which of the following structures?

. Ischiofemoral ligament
. Pubofemoral ligament
. Rectus femoris
. Sartorius
. Gluteus minimus

Correct Answer & Explanation

. Ischiofemoral ligament

Explanation

DISCUSSION: The avulsed fragment represents the origin of the rectus femoris from the anterior inferior iliac spine and the brim of the acetabulum.  Avulsion of the anterior inferior iliac spine is much less common than avulsion of the anterior superior iliac spine with its origin of the sartorius.  The origin of the gluteus minimus is from the outer cortex of the iliac wing and has not been reported as a source of bony avulsion.  The hip capsule is composed of the ischiofemoral and pubofemoral ligaments, in addition to the iliofemoral ligament.  The pelvic attachment of the ischiofemoral ligament is from the ischial part of the acetabulum posteriorly, while the pubofemoral ligament attaches to the pubic portion inferiorly.  Technically, ligaments do not have origins and insertions as muscle tendon groups do, but have attachment sites.REFERENCES: Metzmaker JN, Pappas AM: Avulsion fractures of the pelvis.  Am J Sports Med 1985;13:349-358.Mader TJ: Avulsion of the rectus femoris tendon: An unusual type of pelvic fracture.  Pediatr Emerg Care 1990;6:198-199.

Question 3626

Topic: 2. Trauma

Which of the following factors increase the risk of nonunion in midshaft clavicle fractures when treated nonoperatively?

. Sling immobilization
. Displacement and comminution
. Age less than 40 years old
. Immediate motion exercises
. Male

Correct Answer & Explanation

. Sling immobilization

Explanation

DISCUSSION: Robinson et al have shown that lack of cortical apposition, comminution, female gender, and advancing age are the 4 factors that contribute to nonunion.The Canadian Orthopaedic Trauma Society in a randomized, prospective study showed that for midshaft fracture in adults with 100% displacement, ORIF results in improved DASH and Constant scores (p = 0.001 and p < 0.01, respectively), lower nonunion (2 vs. 7, p=0.042) & lower malunion (0 vs. 9, p=0.001). Surgery resulted in quicker radiographic union (16.4 weeks vs. 28.4 weeks, p=0.001). However, 15% had hardware and wound complications. At one year, the operative group was more likely to be satisfied with the shoulder in general (p=0.002) and the appearance of the shoulder in particular (p=0.001) in comparison to the nonoperative group.Prior studies have shown that greater than 2cm of shortening treated non-operatively results in increased fatigueability and poor outcome, but not necessarily nonunion. The Lazarides article concluded that “Final clavicular shortening of more than 18 mm in male patients and of more than 14 mm in female patients was significantly associated with an unsatisfactory result.”Studies have shown no difference in outcome when treated with a Figure-of-8 harness compared to a simple sling

Question 3627

Topic: 2. Trauma

A 30-year-old man presents with a distal third tibia fracture that has healed in 25 degrees of varus alignment. The patient is at greatest risk of developing which of the following conditions as a result of this malunion?

. Degenerative lumbar spine changes
. Ipsilateral ankle pain and stiffness
. Ipsilateral hip joint degenerative changes
. Contralateral hip joint degenerative changes
. Ipsilateral medial knee degenerative changes

Correct Answer & Explanation

. Degenerative lumbar spine changes

Explanation

CORRECTDISCUSSION: A significant malunion of the distal tibia has important consequences for patient outcome, including pain, gait changes, and cosmesis.The first referenced article by Milner et al looked at long-term outcomes of tibial malunions and noted that varus malunion led to increased ankle/subtalar stiffness and pain regardless of the amount of radiographic degenerative changes.The second referenced article by Puno et al reinforced the concept of decreased functional outcomes of the ankle with tibial malunions, and noted that other lower extremity joints (ipsilateral and contralateral) do not have increased rates of degeneration from such a malunion.

Question 3628

Topic: 2. Trauma

A 29-year-old male sustained a mid-shaft femur fracture in a motor cycle accident. Even if asymptomatic, what additional radiographs must be obtained either preoperatively or intraoperatively before performing intramedullary nailing of the femoral shaft fracture?

. ipsilateral foot/calcaneus
. ipsilateral hip
. contralateral hip
. ipsilateral tibia/fibula
. thoracic spine

Correct Answer & Explanation

. ipsilateral foot/calcaneus

Explanation

DISCUSSION: Ipsilateral femoral neck fractures are seen in 1-9% of femoral shaft fractures and the femoral neck must be properly imaged either preoperatively or intraoperatively in any patient with a femoral shaft fracture. Dedicated hip films, possibly including an internal rotation AP, should be obtained before entering the OR. Daffner et al reported that in 11 of 20 cases of combined femoral shaft and neck fractures, the initial preoperative radiographs did not demonstrate the femoral neck fracture. Intraoperative fluoroscopy should also be used to evaluate for a femoral neck fracture both before (to evaluate for unrecognized fx) and after (to evaluate for iatrogenic fx) IM nailing. Tornetta et al also describe using preoperative CT scans to evaluate for a femoral neck fracture and found that they were able to reduce the number of missed ipsilateral femoral neck fractures.

Question 3629

Topic: 2. Trauma

Figure 26 is the radiograph of a 33-year-old woman who was involved in a high-speed motor vehicle crash. Her initial blood pressure is 80/50 mm Hg and she has a pulse rate of 120 bpm. After hemodynamic stabilization and temporizing measures have been performed, the patient is cleared for surgery. What is the most appropriate method of definitive fixation?

. External fixation
. Open reduction and internal fixation of the pubic symphysis with a two-hole plate
. Open reduction and internal fixation of the pubic symphysis with a two-hole plate and posterior triangular osteosynthesis
. Open reduction and internal fixation of the pubic symphysis with a multi-hole plate
. Open reduction and internal fixation of the pubic symphysis with a multi-hole plate and posterior plate osteosynthesis

Correct Answer & Explanation

. External fixation

Explanation

The patient has sustained an anterior posterior compression (APC) grade II pelvic ring injury. Initial management should consist of pelvic volume reduction with pelvic binding or sheeting. Once the patient is hemodynamically stable, the decision for definitive management should be made. In a retrospective review of more than 200 patients, Sagi and Papp investigated plate osteosynthesis of the pubic symphysis. They found significantly fewer malunions in the multi-hole plate group and a trend toward fewer surgeries in the same group. Typically external fixation should be reserved for temporary fixation and not a definitive management in stable patients. Posterior fixation is reserved for injuries with disruption of the posterior ligamentous constraints, typically APC grade III injuries. Triangular osteosynthesis is a strategy for fixation of unstable vertical shear fractures that require fixation of the pelvis to the lumbar spine.

Question 3630

Topic: 2. Trauma

A 36-year-old woman was injured in a train derailment. She has a significant open depressed skull fracture with active bleeding, a hemopneumothorax, and blood in the left upper quadrant and colic gutter by Focused Assessment with Sonography for Trauma (FAST) examination. Additionally, she has the pelvic injury seen on the CT scans in Figures 18a and 18b. The mortality rate for this patient approaches

. less than 10%.
. 30%.
. 50%.
. 70%.
. greater than 90%.

Correct Answer & Explanation

. less than 10%.

Explanation

DISCUSSION: Mortality following trauma that requires surgical intervention for head, chest, and abdominal injury exceeds 90%.  The type of pelvic fracture is a predictor of associated injury, blood requirements, and overall mortality.  AP III pelvic fractures require the most blood, and are associated with significant abdominal trauma and shock.  Lateral compression pelvic fractures are more associated with head, chest, and occasionally abdominal trauma, and mortality often occurs from associated injuries.REFERENCES: Dalal SA, Burgess AR, Siegel JH, et al: Pelvic fracture in multiple trauma: Classification by mechanism is key to pattern of organ injury, resuscitative requirements and outcome.  J Trauma 1989;29:981-1000.Eastridge BJ, Burgess AR: Pedestrian pelvic fractures: 5-year experience of a major urban trauma center.  J Trauma 1997;42:695-700.Gilliland MD, Ward RE, Barton RM, et al: Factors affecting mortality in pelvic fractures.J Trauma 1982;22:691-693.

Question 3631

Topic: 2. Trauma

All of the following are considered contraindications to the use of functional bracing of a humeral shaft fracture EXCEPT:

. Mid-diaphyseal segmental fracture with ipsilateral pilon fracture
. Mid-diaphyseal fracture with radial nerve palsy from penetrating injury
. Proximal one-third oblique fracture
. Mid-diaphyseal closed fracture with a radial nerve palsy on presentation
. Mid-diaphyseal fracture with a L1 burst fracture and paraplegia on presentation

Correct Answer & Explanation

. Mid-diaphyseal segmental fracture with ipsilateral pilon fracture

Explanation

DISCUSSION: A closed mid-diaphyseal humerus fracture with a radial nerve palsy on presentation is not a contraindication to functional brace management.Commonly accepted parameters for closed treatment include less than 30 degrees of varus angulation, 20 degrees of anterior/posterior angulation, and 3 cm of shortening. Operative indications are: associated vascular injuries, bilateral humeral shaft fractures, polytrauma patient (including paraplegia), segmental fractures, injury to the brachial plexus, pathological fractures, floating elbow, and floating shoulder.The article by Rutgers and Ring found that proximal one-third oblique humeral shaft fractures had an unacceptably high 29% rate of nonunion treated with a functional brace.The article by Sarmiento et al found a 97% rate of union, a radial nerve palsy incidence of 11%, and no contraindication to the use of functional braces in humeral shaft fractures associated with radial nerve palsy.The review article by Defranco and Lawton states that 70% of these radial nerve injuries recover spontaneously. They note that it "seems reasonable, however, to consider surgical intervention (radial nerve exploration) between 4 and 6 months based on the patient’s clinical course."

Question 3632

Topic: 2. Trauma

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?

. CT
. MRI
. Standing radiographs
. Measurement of compartment pressures
. Bone scan

Correct Answer & Explanation

. CT

Explanation

DISCUSSION: 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.REFERENCES: 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.Hunt SA, Ropiak C, Tejwani NC: Lisfranc joint injuries: Diagnosis and treatment.  Am J Orthop 2006;35:376-385.

Question 3633

Topic: Lower Extremity Trauma

Figure 1 is the MR image of a high school soccer player who sustained a right knee injury during a game while making a cut toward the ball. He felt a pop and his leg gave way. During physical examination, as the knee is moved from full extension into flexion with an internal rotation and valgus force, you notice a "clunk" within the knee. What is the most likely biomechanical basis for the "clunk"?

. In extension with internal rotation/valgus force, the medial tibial plateau is subluxated; with flexion, the medial tibial plateau reduces.
. In extension with internal rotation/valgus force, the medial tibial plateau is reduced; with flexion, the medial tibial plateau subluxates.
. In extension with internal rotation/valgus force, the lateral tibial plateau is reduced; with flexion, the lateral plateau subluxates.
. In extension with internal rotation/valgus force, the lateral tibial plateau is subluxated; with flexion, the lateral plateau reduces.

Correct Answer & Explanation

. In extension with internal rotation/valgus force, the medial tibial plateau is subluxated; with flexion, the medial tibial plateau reduces.

Explanation

This patient sustained an isolated anterior cruciate ligament (ACL) injury based upon the mechanism described and examination findings. The finding that produces the “clunk” is the pivot-shift maneuver, which is positive in a knee with an incompetent ACL. With an ACL-deficient knee in full extension and internal rotation, the lateral tibial plateau subluxates anteriorly. As the knee is flexed, the lateral tibial plateau slides posteriorly into a reduced position, causing an audible clunk. Response D correctly describes the pathomechanics that result in the audible clunk heard during the pivot-shift maneuver. Responses A and B are incorrect because they describe the medial tibial plateau, which is not part of the pathomechanics of the pivot shift. Response C is incorrect because in extension, the lateral tibial plateauis subluxated, not reduced.

Question 3634

Topic: 2. Trauma

A 22-year-old man who sustained a Gustilo-Anderson grade IIIC open fracture of the right tibia and fibula was treated with an immediate open transtibial amputation. After two serial debridements, he underwent wound closure with a posterior myocutaneous soft-tissue flap. What is the preferred method of early rehabilitation?

. Bulky gauze dressings with no compression of the traumatized tissues and early non-weight-bearing ambulation
. Bulky gauze dressings with snug compression of the residual limb and early non-weight-bearing ambulation
. Immediate intraoperative prosthetic fitting with a vacuum-formed prosthetic limb, followed by immediate weight bearing
. Rigid plaster dressing, a cast change at 5 to 7 days, and partial weight bearing with an attached pylon when the wound shows signs of healing without infection
. Compression dressing and delayed application of a weight-bearing pylon until the sutures are removed and the wound is well healed

Correct Answer & Explanation

. Bulky gauze dressings with no compression of the traumatized tissues and early non-weight-bearing ambulation

Explanation

DISCUSSION: There is no evidence that early weight bearing enhances ultimate rehabilitation.  At the other extreme, weight bearing should not be delayed for a prolonged period of time.  In a young, healthy individual, the rigid plaster dressing appears to be the safest method of protecting the wound during the early postoperative period.  If the wound appears to be secure, early partial weight bearing can be safely initiated.REFERENCES: Burgess EM, Romano RL, Zettl JH: The Management of Lower Extremity Amputations.  Washington, DC, US Government Printing Office, 1969, also at: www.prs-research.org.Smith DG, McFarland LV, Sangeorzan BJ, et al: Postoperative dressing and management strategies for transtibial amputations: A critical review.  J Rehabil Res Dev 2003;40:213-224.

Question 3635

Topic: 2. Trauma

A 29-year-old obese patient is transferred from an outside facility for the management of a closed-head injury and the fracture shown in Figure A. He presents to the trauma bay as a transient responder to blood products, and undergoes urgent pre-surgical angiography embolization. Surgery is performed within 8 hours from the time of injury. The patient develops a deep wound infection 1 week post-operatively. Which of the following factors would be considered the MOST statistically significant predictor for post-operative infection in this patient.

. Head injury
. Obesity
. Male
. Early surgery
. Transfer from an outside facilityCorrent answer: 2From the following options, only obesity has been shown to be associated with a statistically higher incidence of wound complications following pelvic and acetabular fracture fixation for trauma.Wound complications following pelvic and acetabular fracture fixation is relatively uncommon. Literature suggests and prevalence of 2-8% with closed fracture injuries. Factors shown to increase infection rates include both patient and surgical factors. They include obesity, diabetes, immunocompromised, elderly, pre-operative embolization and open fractures.Sagi et al. looked at the factors contributing to wound infection after pelvic and acetabular surgery. Open pelvic or acetabular fractures were excluded. Of all the factors, only obesity (OR 8, PPV 33%), obesity plus leukocytosis (OR 12, PPV 39%), and preoperative angioembolization (OR 11, PPV 67%) were strong predictors of postoperative infection.Manson et al. aimed to determine if embolization of pelvic arterial injuries before open reduction and internal fixation (ORIF) of acetabular fractures is associated with an increased rate of deep surgical site infection. They retrospective reviewed 1440 patients who underwent ORIF of acetabular fractures. They found a 58% infection rate of the patients who underwent embolization before ORIF vs, historical controls (2%-5%) and angiography without embolization (14%).Figure A shows an AP radiograph and 3D CT reconstruction of a APC3 pelvic ring fracture.Incorrect Answers:

Correct Answer & Explanation

. Head injury

Explanation

OrthoCash 2020

Question 3636

Topic: 2. Trauma

A 40 year-old-man was involved in a motor vehicle accident and sustained the pelvic injury seen in Figures 24a and 24b. Definitive management of the injury should consist of reduction by

. skeletal traction and bed rest.
. anterior external fixation.
. internal fixation of the symphysis pubis.
. internal fixation of the symphysis pubis with supplemental external fixation.
. internal fixation of the symphysis pubis and sacral fracture.

Correct Answer & Explanation

. skeletal traction and bed rest.

Explanation

DISCUSSION: The radiograph reveals disruption of the symphysis pubis and a displaced left sacral fracture.  A posterior injury with displacement of greater than 1 cm is unstable, and a sacral fracture is particularly unstable.  Surgical stabilization is required for these unstable anterior and posterior injuries.  External fixation provides little stability to an unstable posterior pelvic injury. Reduction and internal fixation of the symphysis pubis and sacral fracture will provide the most stable pelvis with the least resultant deformity and allow patient mobilization.REFERENCES: Tile M: Management of pelvic ring injuries, in Tile M, Helfet DL, Kellam JF (eds): Fractures of the Pelvis and Acetabulum, ed 3.  Philadelphia, PA, Lippincott Williams & Wilkins, 2003, pp 168-202.Kabak S, Halici M, Tuncel M, et al: Functional outcome of open reduction and internal fixation for completely unstable pelvic ring fractures (type C): A report of 40 cases.  J Orthop Trauma 2003;17:555-562.

Question 3637

Topic: 2. Trauma

An olecranon fracture-dislocation of the elbow in which the fracture line exits distal to the coronoid process is best managed by open reduction and

. tension band wire fixation of the olecranon.
. plate fixation of the olecranon.
. elbow bridging external fixation
. transarticular Kirschner wire fixation.
. cast immobilization.

Correct Answer & Explanation

. tension band wire fixation of the olecranon.

Explanation

DISCUSSION: Fracture-dislocations of the elbow present difficult management problems.  Standard olecranon fractures normally are not associated with a dislocation; however, the surgeon needs to recognize that some fractures that have a dislocation, in particular a posterior dislocation, represent a Monteggia equivalent.  These injuries are not ulnar shaft fractures because they are fractured at or just distal to the coronoid; however, because of the unstable fracture-dislocation, the forces across this reduction are high.  Two Kirschner wires and a tension band wire provide inadequate fixation.  Therefore, the preferred method of fixation is plate osteosynthesis with a 3.5-mm low-contact dynamic compression plate or reconstruction plate.REFERENCES: Jupiter JP, Kellam JF: Fractures of the forearm, in Browner BD, Jupiter JP, Levine AM, Trafton P (eds): Skeletal Trauma, ed 2.  Philadelphia, PA, WB Saunders, 1998,pp 421-454.Quintero J: Fracture of the forearm, in Ruedi TP, Murphy WM (eds): AO Principles of Fracture Management.  Stuttgart, Thieme, 2000, pp 323-337.Jupiter JB, Leibovic SJ, Ribbans W, Wilk RM: The posterior Monteggia lesion.  J Orthop Trauma 1991;5:395-402.

Question 3638

Topic: 2. Trauma

Which of the following is an FDA approved adjunctive treatment for an acute open tibia fracture being treated with an intramedullary nail?

. Calcitonin
. rhBMP-2
. rhBMP-7
. Teraparatide
. Bisphosphonates

Correct Answer & Explanation

. Calcitonin

Explanation

rhBMP-2 has FDA approval for use when treating acute open tibia fractures with an intramedullary nail.Open tibial shaft fractures can present many treatment challenges. Although its use remains somewhat controversial, rhBMP-2 has been shown to have many positive effects when used to treat acute open tibia fractures. These benefits include accelerated early fracture healing, decreased rates of hardware failure, decreased need for subsequent bone grafting procedures, and decreased infection rates. rhBMP-2 does have FDA approval specifically for use in open tibia fractures being treated with an intramedullary nail.Alt et al. present a comparison of patients with Grade III open tibia fractures treatedwith un-reamed nails with or without rhBMP-2. They found significant decreases in need for secondary interventions such as bone grafting or nail exchange. Mean time to fracture healing was less in the rhBMP-2 group, but this difference was not statistically significant.Govender et al. present a prospective randomized study of 450 patients with open tibia fractures treated with an intramedullary nail with or without rhBMP-2. They found statistically significant decreases in need for secondary intervention, hardware failure, and infection as well as faster wound healing and faster time to fracture union.Wei et al. provide a meta analysis regarding use of rhBMP-2 in open tibia fractures. Due to decreased rates of secondary interventions they estimated a net savings of$6,000 per case when rh-BMP2 was used. They found no significant difference in rates of infection, postoperative pain, hardware failure, or fracture healing at 20 weeks.Incorrect answers:

Question 3639

Topic: 2. Trauma

Which of the following is considered the best measure of the adequacy of resuscitation in the first 6 hours after injury?

. Blood pressure
. Urine output
. Central venous pressure
. Heart rate
. Base deficit

Correct Answer & Explanation

. Blood pressure

Explanation

DISCUSSION: The end point of resuscitation is adequate tissue perfusion and oxygenation.  Blood lactate is the end point of anaerobic metabolism.  The level of blood lactate reflects global hypoperfusion and is directly proportional to oxygen debt.  Two separate prospective studies have verified a significant difference in mortality when blood lactate was used as a measure of resuscitation when compared to traditional parameters (mean arterial pressure, urine output, central venous pressure, and heart rate).  Base deficit is a direct measure of metabolic acidosis and an indirect measure of blood lactate levels.  It correlates well with organ dysfunction, mortality, and adequacy of resuscitation.  It is easy to measure, can be obtained rapidly, and is an excellent assessment of the adequacy of resuscitation.REFERENCES: Porter JM, Ivatury RR: In search of the optimal end points of resuscitation in trauma patients: A review.  J Trauma 1998;44:908-914.Elliot DC: An evaluation of the end points of resuscitation.  J Am Coll Surg 1998;187:536-547.

Question 3640

Topic: 2. Trauma

A 30-year-old man landed on his shoulder in a fall off his mountain bike. An AP radiograph and CT scan are shown in Figures 34a and 34b. Management should consist of

. immobilization in a sling and swathe.
. open reduction and internal fixation.
. humeral arthroplasty.
. subscapularis transfer into the humeral head articular defect.
. a hanging cast.

Correct Answer & Explanation

. immobilization in a sling and swathe.

Explanation

DISCUSSION: The radiograph shows a valgus impacted four-part fracture.  The humeral head is deeply depressed into the metaphysis but is still articulating with the glenoid as seen on the CT scan.  Unlike a “classic” four-part fracture in which the head is dislocated out of the glenoid and devoid of any soft-tissue attachments (high risk of osteonecrosis), this valgus impacted head will have a medial soft-tissue hinge with a lower risk of osteonecrosis.  It is most amenable to open reduction and internal fixation with minimal soft-tissue stripping techniques.  Bone grafting may be necessary on occasion.  Nonsurgical management for displaced proximal humeral fractures generally results in a poor outcome.  This patient does not have a humeral head defect.  A hemiarthroplasty is not indicated.REFERENCES: Jakob RP, Miniaci A, Anson PS, et al: Four-part valgus impacted fractures of the proximal humerus.  J Bone Joint Surg Br 1991;73:295-298.Resch H, Povacz P, Frohlich R, et al: Percutaneous fixation of three- and four-part fractures of the proximal humerus.  J Bone Joint Surg Br 1997;79:295-300.

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