2. Trauma MCQs

DISCUSSIONFigure 26 shows lucent areas of both femoral condyles. This may represent a variation of ossification, in which case this boy’s knee pain is coincidental. Another possibility is atypical osteochondritis dissecans. An MRI will distinguish between the 2 entities and will guide treatment.Figures 27a and 27b show healing rib and distal tibia fractures. These fractures likely are attributable to child abuse. A plain radiographic skeletal survey is sufficient for orthopaedic needs.A triplane fracture of the distal tibia is revealed in Figure 28. A CT scan will quantify displacement and identify fracture fragments for planning of screw trajectories if open reduction and internal fixation is indicated (displacement > 2 mm).In Figure 29, the linear lucency of the capitellum indicates an early osteochondritis dissecans. An MRI will allow staging of the lesion.Figure 30 shows that the left radius and ulna do not align with the humerus; this is the likely result of a transphyseal fracture of the distal humerus. An arthrogram will outline the unossified distal humerus and allow for reduction. For an unstable neonate, this likely can be performed in the NICU.Figures 31a and 31b reveal a widely displaced lateral condyle fracture for which open reduction and internal fixation is required. No advanced imaging is necessary.

The degree of acetabular dysplasia and the age of the child are important considerations when choosing what type of osteotomy to perform. The ability to obtain concentric reduction is a prerequisite of all osteotomies that redirect the acetabulum. Procedures that cut all three pelvic bones allow more displacement and, therefore, correction of acetabular dysplasia. The closer the osteotomy is to the acetabulum, the greater the coverage of the femoral head. Compared with the other acetabular osteotomies, the Ganz periacetabular osteotomy provides the greatest potential for correcting acetabular deficiency because there are no bone or ligamentous restraints to limit correction, but it has the disadvantage of being a technically demanding procedure. The amount of coverage provided by the Salter osteotomy is limited.

In pediatric Monteggia fractures, the annular ligament is commonly interposed in the radiocapitellar joint. Type III is the one most commonly associated with irreducibility of the radial head because of interposition of the annular ligament. The incidence of posterior interosseous nerve injury is high with this lesion. The nerve deficit usually completely resolves rapidly and spontaneously.

A stress fracture of the hip is a relatively common problem in endurance sports. These fractures are classified as compression-side, tension-side, and displaced femoral neck fractures. The MRI scan shows a compression-side stress fracture. Compression-side fractures usually occur in the inferior or calcar area of the proximal femur, and non-weight-bearing crutch ambulation for 6 to 7 weeks will most likely result in healing. Because tension-side fractures have a high risk of displacement, treatment should consist of immediate internal fixation.

The most sensitive study in the diagnosis of exertional compartment syndrome is intracompartmental pressures taken at rest compared to pressures taken immediately after exercise. MRI often can reveal nonspecific muscle edema in exertional compartment syndrome, but this is usually not diagnostic. Arterial Doppler studies are usually unremarkable unless they are taken after exercise, in which case these findings may be abnormal.

Flap necrosis and infection rates are lowest if free flap coverage is performed within 72 hours of injury. Delays beyond 72 hours are associated with a higher rate of complications.

Impaired pronation/supination can be seen if the K-wire is advanced either too radial or too far through the volar (anterior) cortex of the proximal ulna. The anterior interosseous nerve is also at risk with overpenetration. Conversely, migration and loosening of the K-wire is reduced with involvement of the anterior cortex. The etiology of limited rotation was found to be from direct overpenetration of the K-wire, which led to a mechanical block.

Access to complex intra-articular fractures is best achieved by an olecranon osteotomy (OO). Fixation can be with parallel plating or orthogonal plating.Bicolumnar fixation of distal humerus fractures should follow the principles outlined by O'Driscoll: Distal fragments should be held by as many screws as possible; every screw in the distal fragments should pass through a plate; each screw should engage as many articular fragments as possible.Galano et al. review treatment for bicolumnar distal humerus fractures. They note that the olecranon osteotomy, Alonso-Llames triceps sparing and Campbell triceps splitting approaches expose 57%, 46% and 35% of the articular surface, respectively. The OO and paratricipital (triceps sparing) approaches allow for early ROM. Protected motion is required for the O'Driscoll TRAP and Bryan-Morrey approaches for tendon-to-bone healing.Coles et al. retrospectively reviewed the OO in fixation of 70 fractures. Osteotomy fixation was with an intramedullary screw and dorsal ulnar wiring, or with a plate.The rate of OO increased with fracture difficulty (from AO type C1-C3). There was 1 delayed union but no nonunions.Figures A and B show a AO/OTA type C2 intraarticular distal humerus fracture. Figure C is a coronal CT scan showing intraarticular comminution. Illustration A shows fixation of the fracture with bicolumnar plating through an olecranon osteotomy approach. Illustration B shows the various approaches to the distal humerus (left, Campbell triceps splitting; center left, O'Driscoll triceps reflecting anconeus pedicle; center right, Bryan-Morrey approach, leaving the triceps attached laterally to the fasciocutaneous flap, but elevating it off the ulna; right, olecranon osteotomy). Illustration C shows 3 methods of olecranon osteotomy (A and B, Intraarticular transverse; C-F, Extra-articular oblique; G, Intra-articular chevron).Incorrect Answers:(SBQ12TR.84) Figure A shows a radiograph of a 30-year-old male who underwent fixation of a left leg injury just over two years ago. He presents with persistent pain and drainage from the distal wound despite 4 months of oral antibiotics. He has no systemic symptoms. He has a past medical history of Grave's disease and Irritable Bowel Syndrome. What would be the best management at this stage?ReviewTopicChronic suppressive, culture-directed, antibiotic therapyAbove knee amputationEndocrine consultation, irrigation and debridement, removal of hardware and negative-pressure wound therapyIrrigation and debridement, removal of hardware, over-reaming medullary canal, external fixation and culture-directed antibioticsIrrigation and debridement, retention of hardware, acute bone grafting and culture-directed antibioticsThis is a case of fracture nonunion in the setting of chronic osteomyelitis and infected hardware. The best treatment option available would be irrigation and debridement, removal of hardware, ring external fixator and culture directed antibiotics.The management of infected nonunion in the setting of chronic osteomyelitis is technically demanding. The aims of treatment are to eradicate the infection and obtain bone union. Non-surgical options are largely unsuccessful in patients with draining chronic osteomyeltis in the setting of infected hardware and nonunion. Surgical options involve incision and debridement of necrotic tissue followed by reconstruction of bone and possible soft tissue (to provide healthy viable coverage). The most common techniques are ringed fixator/circular frames, staged intramedullary device with or without external fixator, free tissue transfer, or radicaldebridement, bone grafting, and fixation.Motsitsi et al. reviewed the management of infected nonunion of long bones. They suggest that the Ilizarov technique is regarded as a standard treatment in infected nonunion of the tibia. When there is bone defect after debridement, the bone can be shortened or treated with bone transport.Egol et al look at a series of patients with chronic osteomyelitis. Limb salvage should be attempted in all patients. The presence of a chronic draining sinus requires surgical debridement and culture directed antibiotics. Infected hardware should be removed. A two-stage strategy is the best and well-proven treatment option.Figure A shows a intramedullary nail in the left tibia. There is a moderate amount of bone loss at the fracture site with mixed sclerotic bone suggestive of osteomyelitis.Incorrect Answers:

Discussion: All of the answer choices are correct except the risk of compartment syndrome. Intramedullary nailing can increase the risk of compartment syndrome. In comparing IM nailing to non-op, Bone et al showed that IM nailing had a shorter time to union, lower non-union rate, decreased incidence of shortening, and quicker return to work, but no difference in compartment syndrome.

Anterior superior iliac spine avulsion fractures are caused by sudden, forceful contractions of the sartorius and tensor fascia lata. These injuries occur in young athletes through the growth plate with the hip extended and the knee flexed, such as while sprinting or swinging a baseball bat. The athlete will often report a pop or snap at the time of injury. Displaced fractures usually can be seen on radiographs. CT or MRI can be obtained to confirm the diagnosis. In most patients, nonsurgical management consisting of rest and protected weight bearing yields satisfactory outcomes. Surgery is usually reserved for fractures with displacement of more than 3 cm and painful nonunions.

This is the correct answer for various reasons, based on the question. Key points isolated fracture, distal and middle thirds, and only 25% displace. The author is implying minimal displacement. According to Gebuhr, Holmich a fracture such as describe in the question which does not require close reduction and only initial mobilization are better satisfied with a functional brace. Their study revealed that elbow extension/flexion and forearm pronation/supination had no difference with long arm cast, but wrist extension/flexion greatly improved with the functional bracing. Selections (1) more indicated for midshaft (3) is not inappropriate, but the authors felt it was not necessary because there was greater patient satisfaction with functional bracing and same results except wrist motion was better. (4), (5) are indicated for greater severity of fracture and failed union.

Positioning the screw deep in the center of the densest portion of cancellous bone is beneficial. Trumble and associates have shown time to union for scaphoid nonunions to be decreased for centrally placed scaphoid screws. McCallister and associates documented improved biomechanical stability for scaphoid waist fractures repaired with a centrally placed screw vs an eccentrically placed screw.

DISCUSSION: The risk of intraoperative fracture in osteoporotic bone in patients with rheumatoid arthritis is significant. Fractures most often occur during humeral head dislocation and positioning for canal reaming. If the fracture occurs at the greater tuberosity, cerclage suture fixation of the tuberosity fracture with autogenous cancellous bone graft from the resected humeral head is the treatment of choice. REFERENCES: Wright TW, Cofield RH: Humeral fractures after shoulder arthroplasty. J Bone Joint Surg Am 1995;77:1340-1346. Norris TR (ed): Orthopaedic Knowledge Update: Shoulder and Elbow. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 215-225. Frankle MA, Ondrovic LE, Markee BA, et al: Stability of tuberosity reattachment in proximal humeral hemiarthroplasty. J Shoulder Elbow Surg 2002;11:413-420.

DISCUSSION: The risk of infection in a 3B open tibia fracture is most directly related to the timing of the soft-tissue coverage and less related to the size or location of the wound. The wound VAC does not lower or raise the risk of infection in open fractures. It does appear to increase the window of time to obtain coverage without increasing the risk of infection. Additionally, the wound VAC may decrease the probability of needing free tissue coverage. Intramedullary nailing has not been shown to lower the risk of infection in 3B fractures. REFERENCES: Godina M: Early microsurgical reconstruction of complex trauma of the extremities. Plast Reconstr Surg 1986;78:285-292. Dedmond BT, Kortesis B, Punger K, et al: The use of negative-pressure wound therapy (NPWT) in the temporary treatment of soft-tissue injuries associated with high-energy open tibia shaft fractures. J Orthop Trauma 2007;21:11-17. Herscovici D Jr, Sanders RW, Scaduto JM, et al: Vacuum-assisted wound closure (VAC therapy) for the management of patients with high-energy soft tissue injuries. J Orthop Trauma 2003;17:683-688.

DISCUSSION: The patient sustained a comminuted extra-articular distal humeral diaphyseal fracture. In isolation, this fracture would still be amenable to an attempt at closed treatment. His radial nerve palsy alone does not warrant open management, as early exploration has not shown a significant benefit in a closed fracture. In addition, despite the comminution and distal extent of the fracture, it is still amenable to closed treatment, though it may be at higher risk for malunion. However, in this patient with multiple lower extremity injuries, fixation of the humerus can facilitate early mobilization and weight-bearing with his right upper extremity, representing a relative indication for surgical management. The posterior triceps-reflecting approach described can be extended proximally to the level of the axillary nerve. The radial nerve must be found and protected, but the dissection can be carried well proximal to it and the medial triceps origin. The anatomic neck of the humerus cannot be visualized through this approach. The plate functions as a neutralization plate, as multiple lag screws are seen placed outside of the plate, suggesting anatomic reduction and fixation of the fracture prior to applying the plate.

This is a rupture of the anterolateral ligament complex and a portion of the IT band. This injury is highly correlated with a complete ACL injury. In the MRI, the curvilinear or elliptic bone fragment (Segond fracture) projected parallel to the lateral aspect of the tibial plateau, the lateral capsular sign, is seen. The lateral capsular sign is also associated with ACL tears. Thus, this is an MRI showing a complete ACLtear.

In this patient, the hardware was intact for 5 months without any evidence of loosening prior to the catastrophic failure. This suggests that the primary cause of nonunion was poor biology rather than insufficient fixation. Biologic compromise can be caused by either infection, poor blood supply, or lack of osteogenic induction cells. Iliac crest bone graft has been used by some for any nonunion of the clavicle, but two studies have shown that bone graft is not necessary to achieve union. Rigid fixation is all that is required. Infection will still complicate any fixation technique. The radiographs show unicortical screw fixation medially, but the construct did not loosen; therefore, it is not the cause of failure.

DISCUSSION: During the late acceleration phase of throwing, the triceps forcibly contracts, extending the elbow as the ball is released. Normally, this force is absorbed by the anterior capsule and the brachialis and biceps muscles. However, if the ulnar collateral ligament is insufficient, the elbow will be in a subluxated position during extension and cause impaction of the olecranon and the olecranon fossa posteromedially. Over time, osteophyte formation is likely to occur. REFERENCES: Conway JE, Jobe FW, Glousman RE, Pink M: Medial instability of the elbow in throwing athletes: Treatment by repair or reconstruction of the ulnar collateral ligament. J Bone Joint Surg Am 1992;74:67-83. Wilson FD, Andrews JR, Blackburn TA, McCluskey G: Valgus extension overload in the pitching elbow. Am J Sports Med 1983;11:83-88.

DISCUSSIONStudies of titanium elastic nailing for femur fractures demonstrated a higher rate of complications, including angular deformity and construct failure, among patients weighing more than 50 kg (100 pounds). Other methods of fixation are recommended for these patients. Flexible nails are not commonly needed, but they also are not associated with a higher complication rate in children younger than age 6.5. Titanium elastic nailing works well in closed or minimally open transverse midshaft fractures, even in the setting of early or immediate weight bearing.Video 8aVideo 8b

The CT scanogram shows the operative left femur is 8 degrees externally rotated compared to the native right femur. No correction is required unless malalignment is>15 degrees and symptomatic. Therefore, the most appropriate next step would be to continue with postoperative observation and close follow-up.The primary purpose of CT scanogram is to measure the angle of rotation of the femoral neck relative to the femoral condyle. To do this, the right and left femurs must be scanned together using a 5mm helical slice scanner at the hip and knee. The first slice should reveal the alignment of the femoral neck, so as to allow for measurement of the femoral neck-to-horizontal (FNH) angle. The second slice should reveal the alignment of the posterior femoral condyles. This allows measurement of the posterior condyle-to-horizontal (PCH) angle. Finally, to calculate the rotational alignment (RA), the FNH angle and PCH angles are subtracted (e.g., RA = FNH -PCH). Normal RA is usually +5 to +20 degrees, which is also referred to as 5 to 20 degrees of femoral anteversion.Lindsey et al. reviewed femoral malrotation following intramedullary nail fixation. They showed the incidence of rotational malalignment was ~28%. Normal femoral neck anteversion (angle of the femoral neck relative to the transverse axis through the femoral condyles) is ~11-13°. However, they noted that some patients have up to 15° difference in rotation in native limbs. Therefore <15 degrees of rotational difference after fixation is considered acceptable.Gugala et al. examined the long-term functional implications for patients with iatrogenic femoral malrotation following femoral intramedullary nail fixation. Theyshowed that patients can compensate for even significant femoral malrotation (up to 30 degrees) and tolerate it well. However, external femoral malrotation (more common) appears to be better compensated/tolerated than internal malrotation.Figure A shows that the left femoral neck is externally rotated (ER) by 15° to the horizontal (ER15). The right femoral neck is externally rotated (ER) by 4° to the horizontal (ER4). The left distal fragment is ER10. The right distal fragment is internally rotated (IR) by 9°. Thus, left femur has a total (ER15)-(ER10)= (+15)-(+10)=(+5), and right femur has (ER4)-(IR9)= (+4)-(-9)=(+13) to the horizontal. Therefore, the difference is 8 degrees.Incorrect Answers:>15 degrees and symptomatic.