Proximal Biceps tendon rupture (LHB Rupture)
The Biceps is the muscle that lies at the front of the upper arm. Although it is most commonly associated with flexing the elbow its principal function is to supinate the wrist and forearm (turn the arm palm upwards). It may also help stabilise the shoulder joint.
Proximally (at the shoulder) Biceps has two tendons (thus its name). The main tendon (Short Head) originates as part of the conjoint tendon from the coracoid where it is joined to the Coracobrachialis tendon. The second tendon (Long Head) is much smaller and passes from the Supraglenoid tubercle and labrum across the Gleno-humeral joint and into the biciptal groove between Subscapularis and Supraspinatus. It then passes downwards towards the muscle belly.
The Long Head Biceps (LHB) has a course within the joint where it is particularly vulnerable to damage. Tears may be either partial or complete. The Short head biceps is rarely injured.
Proximal Biceps (LHB) tear (at the shoulder):
Proximally the Long Head Biceps (LHB) may become part torn or scuffed or may tear completely. The distal portion of the tendon will typically retract down the arm as a result of tension in the Biceps muscle belly. The muscle belly will tend to bunch slightly as a consequence of this loss of tension, resulting in a cosmetic deformity termed a ‘Popeye’ sign as the Biceps will tend to look slightly larger.
A complete rupture of the LHB rarely produces a significant functional impairment, as the main Short Head will remain intact and functioning.
The concern with a Long Head Biceps rupture is that it is frequently associated with damage to adjacent structures and in particular the rotator cuff, and more specifically the anterior (front) portion of the Supraspinatus tendon and the superior (top) portion of the Subscapularis muscles.
Distal Biceps tear (at the elbow):
Distally (at the elbow) the biceps has a single tendon attaching to the Biceps tubercle of the Radius. Additional insertion is given as a layer to the forearm fascia as the Lacertus Fibrosis.
A complete rupture of the Biceps tendon distally typically results in some weakness of flexion but more marked weakness of supination. If this involves the right arm there may be some noticeable weakness when screwing a screw into a wall or tightening nut with a spanner.
Cause LHB tears:
Tendon tears may occur as a consequence of a single event or injury or they may occur gradually over time where a partial tear progresses.
The acute tear typically occurs following a fall or sudden unanticipated contraction. Even with an acute tear the tendon is likely not to have been normal at the point the tear occurred but may well have been tendinotic even if there were no symptoms associated with this.
LHB tears typically occur progressively with initial fraying of the tendon extending to a partial and then subsequently a full thickness tear. These tear become increasingly frequent with age. Tears may also be associated with repeated activities, particularly those that are overhead.
Tears may be associated with other pathology such as tendinosis, impingement and rotator cuff tears.
Tears of LHB become increasingly common with age.
Loaded overhead activities associated with sport (in particular swimming and tennis), gym work (vertical or military press) or occupational activities (plastering and painting).
Smoking may affect tendon blood supply, healing and repair.
With an acute tear there may be a sudden sharp pain in the shoulder that may extend down the front of the arm. With a partial tear pain may be the predominant feature and there may not be any deformity or weakness.
Pop or Snap
There may be an audible or perceived pop or snap as the tendon tears.
After the tendon has torn completely there may be a cramping sensation in the upper arm and Biceps.
There may be perceived weakness of flexion (bending the elbow) associated with pain or discomfort. The apparent weakness of flexion typically settles with the pain and there is unlikely to be long-term loss of power. Supination (turning the hand palm upwards) power may be affected but this is typically mild.
In complete tears there is often a prominence of the Biceps muscle or ‘Popeye’ sign.
Diagnosis and Investigation
The diagnosis may be apparent from the history and examination. In a complete tear the diagnosis tends to be more apparent but partial tears may be more difficult to identify. Further investigations may be undertaken to confirm the diagnosis and to exclude additional pathology.
Plain radiographs (X-Rays).
Radiographs of the shoulder are typically taken but are often unremarkable. These may demonstrate acromial shape (morphology) associated with an impingement syndrome or other pathology such as Calcific Tendonitis.
Ultrasound scan (USS) or Magnetic Resonance Imaging (MRI) scan.
Scans may be arranged to identify structural damage such as a rotator cuff tear. These scans may visualize the Long Head Biceps and identify a tear, subluxation or fluid around the tendon.
An injection of local anaesthetic often with steroid may be provided to the region around the tendon as confirmation of the diagnosis as well as part of treatment.
Avoidance of exacerbating activities.
In the first instance activities, which exacerbate symptoms, should be avoided. This typically includes repetitive overhead activities and sports including freestyle swimming etc.. The pain associated with a Long Heads Biceps rupture typically settles with time.
Analgesia Anti-inflammatory medication.
Anti-inflammatories eg: Ibuprofen, Diclofenac and VoltarolTM may be helpful in addition to simple painkillers (analgesia) eg: Paracetamol.
Rehabilitation and physiotherapy.
Physiotherapy may be helpful to maintain range of movement and
condition the shoulder.
Local injections of steroid.
Injections of steroid, normally given with a local anaesthetic agent typically produce symptomatic relief in the short or long term. These are useful as diagnostic test as well as offering treatment benefits. Caution is required when considering repeat injections as the steroids may have a detrimental effect on the tendon tissues.
It is exceptionally rare that surgical intervention is required for complete Long Head Biceps ruptures. Very occasional competitive bodybuilders or elite athletes may consider surgery to optimize performance and cosmesis. Partial tears that cause ongoing pain may treated with an arthroscopy (keyhole surgery) or occasionally a small open operation and either Tenotomy (dividing the tendon and removing the damaged tendon) or Tenodesis (dividing the tendon and then fixing it to the bone or an adjacent tissue). Surgical intervention may also be required to address associate pathology such as impingement and rotator cuff tears.
Complications with surgery of this type are uncommon. Following a tenotomy of a part torn LHB rupture there may be a cosmetic ‘Popeye’ deformity. Following a tenodesis there is the risk of fixation and the development of a cosmetic ‘Popeye’ deformity.
Depnding on the surgery undertaken your shoulder may be immobilised temporarily with a sling. Rehabilitation is typically guided by a physiotherapist. Initially the aim is to maintain range of movement before progressing to strengthening exercises. Compliance with the rehabilitation programme will affect the outcome of the surgery undertaken.
Surgery usually improves the pain associated with a Long Head Biceps tear.