BiCeps Tendon Rupture

---

Incidence

• Rare
• Distal biceps tendon rupture represents about 10% of biceps ruptures, with majority being proximal
• Ruptures tend to occur in the dominant elbow (86%) of men (93%) in their 40s

Risk factors

• Your muscle builders with their anabolic steroids
• Smoking has 7.5x greater risk than nonsmokers
• Typically, patients will report a snap or pop as the elbow is eccentrically loaded from flexion to extension

• Weakness and pain, primarily in supination, are hallmarks of this injury
• May produce mid-arm "ball", also be referred to as the reverse “Popeye’s sign” = change in contour of the muscle
• Motor exam often shows loss of supination and flexion, with mostly loss of supination
• Distal swelling and tenderness over antecubital fossa
  • For most complete tears, there will be an Inability to palpate distal biceps tendon in antecubital fossa
  • However, there is a great provocative test you can perform called the Hook test. This was a technique first described in 2007 in an article published in the AJSM (Dr. Shawn O’Driscoll), which was found to be ~100% sensitive and specific
    • Performed by asking the patient to actively flex the elbow to 90° and to fully supinate the forearm. Using you index finger, attempt to hook the lateral edge of the biceps tendon.
    • With an intact / partially torn tendon, finger can be inserted 1 cm beneath the tendon
  • Follow-up study using the Hook test has shown once again near 100& specificity, however lower sensitivity at 82%, but overall a great physical exam maneuver if you have high suspicion!
• The biggest challenge is going to be distinguishing between complete tear and partial tears
• Biceps tendon is absent in complete rupture and palpable in partial rupture (otherwise they have a very similar clinical picture)

Evaluation

• Obtain radiographs to rule-out avulsion fracture (Usually normal)
  •  However, occasionally shows a small fleck or avulsion of bone from the radial tuberosity
• Ultrasound can help with diagnosis--> Use linear probe (high frequency probe) to assess for tendon defects
• Ideally, outpatient MRI will often be used to distinguish between complete tear vs. partial tear or muscle substance vs. tendon tear

Management

• Proximal rupture
  • Sling, ice, NSAIDS, physical therapy, referral to ortho
• Distal
  • Nonoperative
    • Supportive treatment followed by physical therapy
    • Older, low-demand or sedentary patients who are willing to sacrifice function. Most becoming asymptomatic at 4-6 weeks
  • Operative
    • Surgical repair of by fixation of tendon to tuberosity 
    • Indications
      • Young healthy patients who do not want to sacrifice function 
      • Partial tears that do not respond to nonoperative management
      • Surgical treatment should occur within a few weeks from the date of injury
      • Further delay may preclude a straightforward, primary repair