A torn rotator cuff often affects the bicep tendon due to the intimate anatomical connection between the two structures in the shoulder. The bicep muscle has two tendons, but the long head of the biceps tendon (LHB) travels through the joint, placing it in direct proximity to the rotator cuff (RC) tissues. Damage to the cuff rarely occurs in isolation, frequently leading to secondary pain and damage in the LHB. A torn RC can quickly become a combined pathology involving both the cuff and the biceps tendon.
Understanding the Shoulder’s Interconnected Anatomy
The long head of the biceps tendon (LHB) plays a unique role in shoulder stability. This tendon originates at the top of the shoulder socket (glenoid) and courses through the joint before exiting into a bony channel on the upper arm bone called the bicipital groove. The LHB is secured in this groove by a complex soft-tissue apparatus referred to as the biceps pulley or sling.
This sling is formed by the superior glenohumeral and coracohumeral ligaments, along with fibers extending from the supraspinatus and subscapularis rotator cuff tendons. Since the LHB is anchored and stabilized by these surrounding RC structures, any tear or degeneration in the cuff directly compromises the LHB’s protective environment. The tendon also functions as a dynamic stabilizer, helping to depress the humeral head and prevent it from migrating upward.
How Rotator Cuff Damage Leads to Bicep Tendon Issues
Damage to the rotator cuff removes the structural support, leading to a cascade of secondary issues for the LHB. Pathology, such as inflammation and instability, is highly common in patients presenting with rotator cuff tears. This correlation is most pronounced when the tear involves the subscapularis tendon, which forms a considerable part of the LHB’s retaining pulley system.
Biceps tenosynovitis, inflammation of the LHB and its protective synovial sheath, is one of the most common secondary issues. Altered shoulder mechanics caused by torn cuff tissue subject the biceps tendon to excessive friction and irritation as it glides within the bony groove. This chronic inflammation and fraying can weaken the tendon over time, making it susceptible to further injury.
Rotator cuff tears also frequently result in LHB instability, where the tendon moves out of its proper position, a condition called subluxation or dislocation. If the tear affects the anterior cuff—specifically the subscapularis tendon—the stabilizing sling is disrupted, allowing the LHB to shift medially out of the bicipital groove. This physical displacement often causes a painful clicking or popping sensation in the front of the shoulder.
Chronic instability and friction can eventually lead to a biceps tendon tear. Approximately half of all complete ruptures of the LHB are associated with an underlying rotator cuff tear, most commonly involving the supraspinatus tendon. The chronic wear and tear caused by the cuff damage ultimately compromises the structural integrity of the LHB, leading to its eventual failure.
Clinical Diagnosis and Combined Treatment Approaches
Diagnosing combined rotator cuff and biceps tendon pathology requires a thorough physical examination paired with diagnostic imaging. Clinicians often use specific maneuvers, such as the Speed’s test or Yergason’s test, to provoke pain in the bicipital groove, indicating potential LHB involvement. Tenderness upon palpation directly over the biceps groove is also a significant clinical finding.
Magnetic Resonance Imaging (MRI) is the standard imaging tool used to visualize both the rotator cuff tear and the long head of the biceps tendon. An MRI can confirm a cuff tear and also show signs of LHB pathology, such as tendon thickening, increased fluid around the tendon (suggesting tenosynovitis), or tendon subluxation or tearing. However, the sensitivity of MRI for subtle findings like partial LHB tears and tendinitis can be limited, which is why clinical tests remain essential.
Treatment for combined injury is often coordinated to address both sources of pain and dysfunction simultaneously. Non-surgical management, including physical therapy and corticosteroid injections, is generally attempted first for isolated tendinitis or small, non-displaced tears. However, when a significant rotator cuff tear requires surgical repair, the associated LHB pathology is usually addressed during the same procedure.
Surgical Options for the LHB
The two main surgical options for the LHB are tenotomy and tenodesis, which are performed to eliminate the LHB as a pain generator.
Biceps Tenotomy
A biceps tenotomy involves simply cutting the LHB at its attachment site and allowing it to retract down the arm. This is generally a simpler and faster procedure.
Biceps Tenodesis
A biceps tenodesis involves cutting the tendon and then reattaching it lower down on the humerus bone, outside of the shoulder joint.
Tenodesis is often preferred for younger or more active patients to maintain the normal length-tension relationship of the muscle and reduce the risk of cosmetic deformity, known as a “Popeye” sign, or muscle cramping. By addressing the damaged biceps tendon concurrently with the rotator cuff repair, surgeons aim to restore a stable, pain-free shoulder with improved long-term functional outcomes.