What are the clinical signs and management options for a biceps tendon rupture?

Biceps Tendon Rupture: Clinical Signs and Management

Complete distal biceps tendon ruptures should be treated with early surgical reattachment for optimal functional outcomes, while partial tears <50% can be managed conservatively with rest, immobilization, and progressive rehabilitation. 1, 2

Clinical Signs and Diagnosis

Physical Examination Findings

• Visible and palpable deformity: Proximal retraction of the biceps muscle belly creating an abnormal contour
• Ecchymosis: Bruising in the antecubital fossa
• Pain: Acute antecubital pain, often described as a "tearing sensation" 2
• Weakness: Decreased strength in elbow flexion and forearm supination 2
• Hook test: Inability to hook the examiner's finger under the biceps tendon in the antecubital fossa (indicates complete rupture)
• Asymmetry: Comparison with the unaffected arm reveals differences in contour and function 1

Distinguishing Complete vs. Partial Ruptures

• Complete rupture: Inability to palpate the tendon in the antecubital fossa, visible deformity, significant weakness
• Partial rupture: Tendon still palpable, pain with resisted flexion and supination, less obvious deformity 3

Imaging

1. Plain radiographs (3-view series: AP, lateral, oblique):

   • May show hypertrophic bone formation at the radial tuberosity
   • Can detect avulsion fractures or calcific tendinopathy 1, 2

2. Ultrasound:

   • First-line imaging for suspected tendon rupture
   • Non-invasive, readily available, cost-effective
   • Sensitivity 95%, specificity 71% for complete vs. partial tears 1

3. MRI:

   • Superior for definitive assessment and tear classification
   • Particularly useful for partial tears or when surgical intervention is being considered
   • Sensitivity 76%, specificity 50% 1

Management

Complete Ruptures

• Early surgical reattachment is recommended for optimal results, especially in active individuals 2, 4
• Surgical options include:
  • Modified two-incision technique (most widely used)
  • Anterior single-incision technique (equally effective if radial nerve is protected)
  • Suspensory cortical button technique (maximum peak load to failure in biomechanical studies) 4
• Surgical repair should ideally be performed within 2-3 weeks of injury for best outcomes 2

Partial Ruptures

• Management based on tear size:
  • <50% tear: Conservative management or surgical debridement of surrounding synovitis 3
  • >50% tear: Division of remaining tendon and complete surgical repair 3

Conservative Management

• Indicated for:

  • Partial tears <50%
  • Elderly or low-demand patients
  • Patients with significant comorbidities
  • Chronic ruptures where surgical repair is challenging

• Components include:

  • Relative rest and activity modification
  • Brief immobilization (avoid prolonged immobilization to prevent stiffness) 1
  • Pain management with acetaminophen and NSAIDs (if not contraindicated)
  • Progressive rehabilitation

Rehabilitation Protocol

1. Early phase (0-2 weeks):

   • Protection, relative rest
   • Gentle range of motion exercises to prevent stiffness 1

2. Intermediate phase (2-8 weeks):

   • Gradual progressive strengthening exercises
   • Continued range of motion exercises 1

3. Advanced phase (8+ weeks):

   • Formal strengthening program
   • Return to unrestricted activities by 5 months post-injury/surgery 2

Potential Complications

Surgical Complications

• Sensory and motor neurapraxia (particularly of the radial nerve)
• Infection
• Heterotopic ossification 4
• Rerupture

Conservative Management Pitfalls

• Persistent weakness in supination and flexion
• Chronic pain
• Decreased functional capacity, especially for high-demand activities 5

Special Considerations

• Distal biceps ruptures occur most commonly in men aged 40-60 years, typically in the dominant arm 2
• The injury typically occurs during eccentric contraction when an unexpected extension force is applied to the flexed arm 2
• Degenerative changes, decreased vascularity, and tendon impingement may precede rupture 4
• Delayed diagnosis can lead to tendon retraction, making later surgical repair more challenging and potentially requiring tendon augmentation 2