Is indentation of the distal bicep (biceps brachii muscle) normal after distal bicep tendon repair?

Indentation of Distal Biceps After Repair

Indentation of the distal biceps muscle is a normal finding after distal biceps tendon repair and does not typically indicate a complication or failure of the repair. While imaging studies like ultrasound and MRI can be used to evaluate the integrity of the repair, the presence of an indentation alone is not a cause for concern.

Normal Anatomy and Post-Repair Appearance

• The distal biceps tendon attaches to the radial tuberosity and is crucial for elbow flexion and forearm supination
• After surgical repair, the following are normal findings:
  • Indentation or contour change at the distal aspect of the biceps muscle
  • Altered muscle appearance on imaging studies
  • Some degree of muscle retraction even with successful tendon reattachment

Imaging Evaluation of Distal Biceps Repairs

Ultrasound

• Ultrasound can effectively evaluate the distal biceps tendon post-repair 1
• Shows good accuracy in detecting complete tears (95% sensitivity) 1
• Less effective for partial tears (sensitivity 59.1%) 1
• Can identify successful tendon reattachment despite muscle indentation

MRI

• Gold standard for evaluating tendon integrity post-repair
• Superior for detecting partial tears compared to ultrasound 1
• Can distinguish between normal post-surgical changes and re-rupture
• The FABS view (flexion-abduction-supination) may provide better visualization 1

Clinical Significance of Indentation

The presence of an indentation in the distal biceps after repair should be evaluated in the context of:

1. Functional outcomes: Assess elbow flexion and forearm supination strength
2. Pain levels: Persistent pain may indicate complications
3. Time since surgery: Some indentation is expected during the healing process

Potential Complications vs. Normal Findings

Normal Findings:

• Visible indentation or contour change
• Mild strength deficits that improve over time
• Negative hook test (inability to hook finger under the biceps tendon)

Concerning Findings (Not Normal):

• Complete absence of tendon on imaging
• Significant weakness in flexion and supination
• Positive hook test
• Re-rupture (rare at 1.5% according to research) 2

Rehabilitation Considerations

Post-repair rehabilitation should follow a phased progression 3:

• Initial protection phase with limited motion
• Progressive strengthening as healing progresses
• Return to full activities typically by 4-6 months

Key Points for Clinicians

• Indentation of the distal biceps after repair is a normal finding and not indicative of repair failure
• Clinical assessment should focus on function rather than appearance
• Re-rupture rate is very low (1.5%) and typically occurs within 3 weeks of surgery 2
• Long-term outcomes after distal biceps repair are generally excellent with 88% subjective satisfaction rates 4
• Complications are more related to nerve injury or heterotopic ossification than to the appearance of the muscle 5

If there are concerns about repair integrity, MRI is the most accurate imaging modality to assess the status of the repair 1, though ultrasound can be a reasonable alternative with good sensitivity for complete tears 1.