Chapter 171. Forearm and Elbow Injuries

Clinical Features

Patients with proximal long-head biceps tendon ruptures typically describe a “snap” or “pop” and complain of pain in the anterior shoulder. Examination reveals tenderness, swelling, and crepitus over the bicipital groove in the anterior shoulder. A midarm “ball” (the distally retracted biceps) appears when the elbow is flexed. Elbow flexion strength is maintained due to the preserved action of the brachialis and supinators. This is in contrast to distal bicep tendon rupture where elbow flexion and supination is weak. Examination of distal biceps rupture reveals swelling, ecchymosis, tenderness, and inability to palpate the tendon in the antecubital fossa. With the patient seated and the elbow flexed and forearm resting on the patient's lap, the examiner squeezes the muscle belly of the biceps causing the forearm to supinate (biceps squeeze test). If no supination is noted, then this is a positive test indicating a distal biceps tendon rupture. Patients with triceps tendon ruptures present with pain, swelling, and tenderness proximal to the olecranon; a sulcus with a proximal mass (the proximally retracted triceps tendon) may be palpable. Forearm extension is weak. A modified Thompson test can be used to assess triceps function. With the arm supported, elbow flexed at 90°, and forearm hanging in a relaxed position, squeezing the triceps muscle should produce extension of the forearm unless a complete tear is present.

Diagnosis and Differential

Diagnosis is clinical. Obtain radiographs to exclude an associated avulsion fracture.

Emergency Department Care and Disposition

Treatment includes sling, ice, analgesics, and referral to an orthopedic surgeon for definitive management. Complete tendon tears in young active individuals often require surgical repair.

Clinical Features

The majority of elbow dislocations are posterolateral. On examination, the patient holds the elbow in 45° flexion. Significant swelling of the elbow often obscures the olecranon, which is directed posteriorly. Neurovascular assessment is essential (Table 171-1). An open dislocation, absence of radial pulse before reduction, and presence of systemic injuries are all factors associated with arterial injury.

Diagnosis and Differential

Radiographs confirm the diagnosis. The lateral view reveals both the ulna and radius displaced posterior. The AP view reveals either medial or lateral displacement of the ulna and radius with maintenance of their normal relationship to each other. The presence of associated fractures, especially to the radial head and coronoid process, can render the elbow joint unstable and complicate treatment.

Emergency Department Care and Disposition

The goals of treatment are reduction with procedural sedation and recognition of neurovascular complications, associated fractures, and postreduction instability. Closed reduction of the elbow is achieved by placing gentle longitudinal traction on the wrist and forearm while an assistant applies countertraction on the arm. Any medial or lateral displacement is corrected with the other hand. A palpable clunk indicates a successful reduction. Range the elbow fully to assess stability. Assess neurovascular status after reduction and for a period of observation. Obtain postreduction films. Immobilize the elbow in a long-arm posterior splint with the elbow in slightly less than 90° of flexion, and arrange for close orthopedic follow-up. Immediate orthopedic consultation is necessary for patients with instability in extension, neurovascular compromise, or open dislocations.

Clinical Features

Radial head fractures present with pain, swelling, and tenderness over the lateral elbow, and inability to fully extend the elbow. Supracondylar and intercondylar fractures present with significant swelling, tenderness, and limited range of motion at the elbow. Supracondylar fractures may resemble a posterior elbow dislocation. Olecranon fractures present with pain, swelling, and crepitus over the posterior elbow. A neurovascular assessment is essential in all elbow fractures. Potential complications of supracondylar fractures are numerous (Table 171-2). A decreased or absent radial pulse is common in children and often secondary to transient vasospasm. Signs of Volkmann ischemic contracture include refusal to open the hand, pain with passive extension of the fingers, and forearm tenderness.

Diagnosis and Differential

Fracture lines may not be visible on standard AP and lateral radiographs of the elbow. Abnormal fat pads, posterior fat pad sign, or prominent anterior fat pad (“sail sign”) may be the only evidence of injury. Disruption of the radiocapitellar line may be another clue to injury. A line drawn from the center of the radial shaft should transect the radial head and capitellum in all views.

Emergency Department Care and Disposition

Immobilization in a splint and orthopedic referral are appropriate for nondisplaced fractures. Treat nondisplaced radial head fractures with sling immobilization. Immediate orthopedic consultation is warranted for all displaced fractures, open fractures, and evidence of neurovascular compromise. Admit patients with significant swelling and displaced fractures for observation of neurovascular status.

Clinical Features

Both bone fractures present with swelling, tenderness, and deformity of the forearm. Isolated ulna or radius fractures present with localized swelling and tenderness. Monteggia fracture-dislocation, a fracture of the proximal third of the ulna with a radial head dislocation, presents with significant pain and swelling over the elbow. Galeazzi fracture-dislocation, a fracture of the distal radius with an associated distal radioulnar joint dislocation, presents with localized tenderness and swelling over the distal radius and wrist.

Diagnosis and Differential

AP and lateral radiographs confirm the diagnosis. In a Monteggia fracture, the radiocapitellar line is disrupted, and the apex of the ulna fracture points in the direction of the radial head dislocation. In a Galeazzi fracture, the distal radioulnar joint space is widened on the AP view, and the ulna is displaced dorsally on the lateral view.

Emergency Department Care and Disposition

Treat nondisplaced fractures with long-arm splint immobilization and referral to orthopedics. Immediate orthopedic consultation is necessary for all displaced fractures. Closed reduction is often adequate for both bone fractures in children. Open reduction and internal fixation is usually required for displaced fractures in adults and for Monteggia and Galeazzi fracture-dislocations.