Pectoralis Major Ruptures: Tear Patterns and Patient Demographic Characteristics

Area of Science:

• Orthopedic surgery
• Sports medicine
• Musculoskeletal research

Background:

• Pectoralis major (PM) muscle has a complex, multilaminar insertion on the proximal humerus, with distinct anterior and posterior tendon layers.
• Understanding tear patterns and patient demographics in surgically treated PM ruptures is limited.

Purpose of the Study:

• To detail demographic characteristics of patients with clinically significant PM ruptures.
• To describe surgical findings of PM tear patterns.

Main Methods:

• Retrospective analysis of a single-surgeon case series (2003-2017) involving surgically treated PM tears.
• Data collected included patient demographics, tear pattern classification, and treatment type (repair/reconstruction).
• Study design: Case series with Level of evidence, 4.

Main Results:

• 104 surgical cases of PM tendon rupture were analyzed; 100 underwent primary repair, 4 had dermal allograft reconstruction.
• All patients were male, with an average age of 36.5 years.
• Chronic tears (>6 weeks) comprised 63.6% of cases, with 96% occurring at or near the musculotendinous junction/insertion. The most common pattern was a partial-thickness, complete-width tear of the posterior tendon layer.

Conclusions:

• Pectoralis major ruptures typically occur at or between the musculotendinous junction and insertion, frequently involving the posterior tendon layer.
• Primary repair is a safe and effective treatment for the majority of chronic PM tears.