What physical examination findings and tests should be performed for a suspected elbow dislocation?

Physical Examination Findings and Tests for Suspected Elbow Dislocation

Immediately assess neurovascular status, perform stability testing under stress, and evaluate for associated fractures through systematic palpation and range of motion testing. 1

Initial Assessment

Neurovascular Examination

• Check radial pulse, capillary refill, and sensation in median, radial, and ulnar nerve distributions before any manipulation, as neurovascular injury can complicate elbow dislocations 2, 3
• Test motor function of all three major nerves (median, radial, ulnar) to identify nerve injury 2

Inspection and Palpation

• Observe for obvious deformity, swelling, and ecchymosis around the elbow joint 2, 3
• Palpate bony landmarks systematically: medial epicondyle, lateral epicondyle, radial head, olecranon process, and coronoid process to identify associated fractures 2, 3
• Assess for tenderness along the medial collateral ligament (MCL) and lateral collateral ligament complex, as these are commonly disrupted 4, 5

Post-Reduction Stability Testing

Stress Fluoroscopy (Critical Step)

Perform stress fluoroscopy immediately after reduction to quantify instability, as this directly predicts outcomes and guides treatment decisions 1, 4:

• Test at full extension, 30° of flexion, and with varus/valgus stress in pronation and supination 1, 4
• <10° of joint widening = slight instability (better prognosis, conservative management) 1, 4
• >10° of joint widening = moderate instability (significantly worse Mayo Elbow Performance Scores) 1, 4
• Frank redislocation on stress testing = gross instability requiring immediate surgical fixation 1, 4

Physical Examination Maneuvers for Instability

Posterolateral Rotatory Instability Tests (most common pattern) 6, 7:

• Lateral pivot-shift apprehension test: Most sensitive test—patient experiences apprehension during extension with forearm supination 6, 7
• Posterolateral rotatory instability test: Reproduces actual subluxation with clunk on reduction (often requires anesthesia) 6
• Posterolateral rotatory drawer test: Rotatory version of knee drawer test 6
• Stand-up test: Patient pushes up from sitting with hand at side and elbow fully supinated, reproducing symptoms 6

Valgus Stress Testing (for medial instability) 5:

• Apply valgus stress at 30° of flexion to assess MCL integrity
• Anterior dislocations particularly require careful valgus stress examination, as medial structures are commonly disrupted 5

Range of Motion Assessment

• Test active and passive flexion-extension arc, noting any clicking, snapping, clunking, or locking 6, 7
• Assess pronation-supination with elbow at 90° flexion 4, 2
• Symptoms typically occur in the extension portion of the arc with forearm supination in posterolateral rotatory instability 6, 7

Critical Pitfalls to Avoid

• Never assume stability after reduction—patients with moderate instability (>10° widening) have significantly worse outcomes 1
• Do not miss coronoid fractures, as they indicate severe instability and require CT imaging 1
• Perform examination under anesthesia if instability is suspected but difficult to assess due to patient guarding 5, 7
• Recheck neurovascular status after any manipulation or reduction 2
• Test for both posterolateral and medial instability patterns, as anterior dislocations have different injury patterns than posterior dislocations 5

Dynamic Assessment

• Perform active finger motion testing immediately to prevent hand stiffness 1
• Dynamic ultrasound can demonstrate nerve dislocation in ulnar nerve neuropathy if available 4