What is the best course of treatment for a patient with a suspected torn right arm biceps (bicep) injury, presenting with bulging?

Management of Suspected Biceps Tendon Rupture with Bulging Deformity

For a patient presenting with a bulging bicep ("Popeye deformity") suggesting a torn biceps tendon, immediate referral to orthopedic surgery is recommended for early surgical repair, particularly in healthy, active individuals, as this provides superior restoration of forearm supination strength and elbow flexion compared to conservative management. 1

Immediate Assessment and Diagnosis

Clinical Examination

• Confirm the characteristic "Popeye deformity" - visible and palpable bulging of the biceps muscle belly in the mid-arm, which indicates retraction of the ruptured tendon 2, 3
• Palpate the antecubital fossa - inability to palpate the distal biceps tendon confirms complete rupture, while a palpable tendon suggests partial tearing 4, 5
• Test for weakness in elbow flexion and forearm supination, which are the primary functional deficits 1, 5
• Document the mechanism of injury - typically occurs from sudden eccentric contraction or unexpected extension force applied to a flexed arm 3, 5

Initial Imaging Protocol

• Obtain plain radiographs first (anteroposterior in internal/external rotation plus axillary or scapular-Y view) to exclude associated fractures, bony avulsions, or glenohumeral dislocation 6
• Proceed directly to MRI without contrast as the definitive imaging study - this is the gold standard with 92.4% sensitivity and 100% specificity for complete distal biceps tears 2, 6
• Request the FABS view (flexion-abduction-supination) specifically on the MRI order for optimal distal biceps visualization 2, 6
• Avoid relying on ultrasound alone - while rated equally appropriate by the American College of Radiology when MRI is contraindicated, ultrasound has significantly lower accuracy (45.5% vs 86.4% for MRI) and particularly poor performance for partial tears 2, 6

Treatment Decision Algorithm

For Complete Ruptures (Most Likely Given Bulging Deformity)

• Refer urgently to orthopedic surgery for early surgical repair - this is the standard of care for healthy, active patients 1, 5
• Timing is critical - early surgical reattachment (within weeks) provides optimal results, while delayed intervention increases complication risk and makes tendon mobilization more difficult due to proximal retraction and scarring 5, 7
• Expected outcomes with surgery: near-complete restoration of forearm supination strength and improved elbow flexion strength compared to nonoperative management 1, 5

For Partial Ruptures (If MRI Shows <50% Tear)

• Consider nonoperative management with activity modification and physical therapy for tears involving less than 50% of the tendon 4
• Surgical repair is indicated for partial tears greater than 50% - the remaining tendon should be divided and the entire tendon repaired as a single unit 4

Nonoperative Management (Rarely Appropriate for Complete Tears)

• Reserve for elderly, sedentary patients or those with significant medical comorbidities who cannot tolerate surgery 1
• Counsel patients that nonoperative management results in permanent weakness of forearm supination (20-40% deficit) and elbow flexion (10-30% deficit) 1, 5

Common Pitfalls to Avoid

• Do not delay imaging or referral - chronic ruptures (>4 weeks) have worse surgical outcomes due to tendon retraction, muscle scarring, and may require tendon augmentation 5, 7
• Do not assume partial tear based on palpable tendon alone - MRI is essential to quantify the extent of injury and guide surgical planning 2, 4
• Do not use ultrasound as the sole diagnostic modality when MRI is available - its 45.5% accuracy for complete tears and poor performance for partial tears can lead to misdiagnosis 2, 6
• Do not recommend conservative management without discussing functional deficits - patients must understand the permanent strength loss that occurs without surgical repair 1, 5

Surgical Considerations

• Modified two-incision technique is the most widely used repair method, minimizing risk of radial nerve injury but carrying higher risk of heterotopic ossification 5, 7
• Single anterior incision techniques may be equally effective with lower heterotopic bone formation risk but require meticulous protection of the posterior interosseous nerve 5, 7
• Postoperative rehabilitation requires protected motion for 8 weeks, formal strengthening beginning at 8 weeks, and return to unrestricted activities by 5 months 5