Getting Straight to the Point on Triceps Tendon Injuries

Tendinopathies of the triceps tendon, and the potential serious sequalae of partial and complete ruptures, are a relatively rare but debilitating condition that can affect power athletes⁽¹⁾. For the power athlete participating in a ‘push’ based sport such as powerlifting, contact football, and martial arts/combat sports, triceps tendon pathology can cause significant symptoms and be functionally limiting^(2-4).

The more common tendon injuries include the lateral and medial epicondyle tendons (extensor origin and flexor origin) and the distal bicep tendon⁽⁵⁾. It has been estimated (using magnetic resonance imaging [MRI]) that only 3.8% of tendinopathies affect the triceps tendon⁽⁶⁾. Along the triceps tendon injury continuum, partial tears are the most common triceps injury comprising around 23% of the distal triceps tendon injuries.

As the average age of those injured is around 46 years, this suggests that developing tendon degeneration is a necessary precursor to partial or complete rupture⁽⁶⁾. The serious end-stage pathology is a tendon rupture; however, this has been estimated to be extremely rare (in less than 1% of serious tendon injuries to the upper limb)⁽¹⁾.

It is more common for serious injuries such as tendon rupture to affect males between the ages of 40-50 at a ratio of 11:1 ratio of males to females^(6,10,11). The incidence of chronic triceps tendinopathy is unknown; many cases of triceps tendon pain may go unreported as often, gym goers simply modify the choice of exercises to avoid tendon pain.

Anatomy

The primary function of the triceps is to extend the elbow, and the long head of the triceps can also assist in shoulder extension movements. The exact anatomy of the distal triceps insertion may therefore be important for the surgeon to understand when repairing the distal triceps tendon.

The triceps brachii is composed of three muscle bellies (see Figures 1 and 2)⁽⁷⁾:

1. The long head arises off the infraglenoid tubercle of the scapula. As this muscle crosses two joints, it is bi-articular and is influenced by the shoulder flexion angle.
2. The medial head originates off the posterior aspect of the humerus distal to the spiral groove.
3. The lateral head originates off the lateral intermuscular septum and the posterolateral aspect of the humerus above the spiral groove.