Understanding Pectoralis Major Tears: A Comprehensive Guide for Athletes, Sports Coaches, and Clinicians

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 Understanding Pectoralis Major Tears: A Comprehensive Guide for Athletes, Sports Coaches, and Clinicians

Keywords: pectoralis major tear, chest muscle rupture, shoulder injury MRI, pectoralis tendon rupture, sports injury chest, pectoralis major imaging, muscle tear MRI, pectoralis major recovery

Introduction

The pectoralis major tear is a relatively uncommon but clinically significant injury, particularly prevalent among active individuals and athletes engaged in high-intensity resistance training such as bench pressing. Due to its dramatic presentation and the importance of early intervention, accurate diagnosis through imaging and appropriate management are essential for favorable outcomes. This article provides a comprehensive overview of the etiology, pathophysiology, clinical presentation, imaging features, treatment, and prognosis of pectoralis major tear, integrating illustrative MRI examples for educational purposes.

Anatomy of the Pectoralis Major

The pectoralis major is a thick, fan-shaped muscle located on the anterior chest wall, consisting of two heads:

  • Clavicular head: originates from the medial half of the clavicle.

  • Sternocostal head: arises from the sternum and the upper six costal cartilages.

Both heads converge to insert on the lateral lip of the bicipital groove of the humerus, facilitating adduction, internal rotation, and flexion of the shoulder joint.

Etiology and Risk Factors

Pectoralis major tear typically results from a violent eccentric contraction of the muscle. It often occurs during weightlifting, especially during bench press activities, where the muscle is suddenly overloaded while lengthening.

Common risk factors include:

  • Male sex (predominantly affects males aged 20–40)

  • Anabolic steroid use

  • Competitive athletics (e.g., bodybuilders, football players)

  • Improper weightlifting technique

  • Previous history of shoulder trauma

Pathophysiology

The tear usually occurs at the musculotendinous junction, where the muscle fibers transition to tendon, a region vulnerable to tensile stress. In severe cases, the rupture may involve the tendinous insertion at the humerus or even avulsion from the bone.

Following the injury:

  • Acute inflammatory response triggers edema and hemorrhage.

  • Disruption of normal muscular continuity leads to pain and functional impairment.

  • Over time, if not treated, fibrosis and fatty infiltration may develop.

Clinical Presentation

Patients with a pectoralis major tear typically present with:

  • Sudden, sharp pain in the chest or upper arm

  • A "popping" sensation during exertion

  • Swelling and bruising over the chest or upper arm

  • Weakness in shoulder adduction and internal rotation

  • Visible deformity or asymmetry in the anterior chest wall

Imaging Features

MRI is the gold standard for evaluating soft tissue injuries of the pectoralis major.

[Figure 1] Coronal T2 Weighted Image

This coronal T2-weighted image shows marked edema and muscle fiber discontinuity at the musculotendinous junction of the pectoralis major.

[Figure 2] Axial T2 Weighted Image

The axial T2 image demonstrates hyperintensity consistent with muscle edema and partial fiber rupture.

[Figure 3] Axial T2 Fat Saturated Image

Fat-saturated T2 imaging highlights fluid-sensitive changes more clearly, showing significant soft tissue swelling and intramuscular bleeding.

[Figure 4] Coronal STIR Image

This sequence confirms extensive soft tissue edema, aiding in delineating the extent of injury and surrounding involvement.

MRI Findings Summary:

“A nearly complete rupture of the pectoralis major muscle was observed at the musculotendinous junction, with contusion/edema of the muscle and surrounding soft tissues.”

MRI helps in grading the tear:

  • Grade I: Strain or contusion

  • Grade II: Partial-thickness tear

  • Grade III: Full-thickness tear (either at the musculotendinous junction or tendon insertion)

Treatment Strategies

Management depends on the extent of the tear, patient activity level, and functional demands.

Non-Surgical Management:

  • Reserved for partial tears or low-demand patients

  • Includes rest, physical therapy, and anti-inflammatory medications

  • May lead to cosmetic deformity and decreased strength

Surgical Repair:

  • Indicated for complete ruptures, especially in athletes

  • Involves reattaching the torn tendon to the humerus using suture anchors

  • Outcomes are better when surgery is performed within 6 weeks of injury

Rehabilitation

Rehabilitation is critical post-injury or surgery and follows a structured protocol:

  1. Immobilization phase (0–3 weeks): Sling use, pain control

  2. Passive ROM phase (3–6 weeks): Gentle stretching

  3. Active ROM and strengthening (6–12 weeks): Progressive resistance training

  4. Return to sport (3–6 months): After full range of motion and strength recovery

Prognosis

With early surgical repair and proper rehabilitation, most patients regain 90–100% of pre-injury strength and function. Delayed treatment may result in:

  • Persistent weakness

  • Muscle atrophy

  • Cosmetic deformity

  • Chronic pain

Differential Diagnosis

  • Deltoid strain

  • Biceps tendon rupture

  • Rotator cuff tear

  • Costochondral injury

  • Sternoclavicular joint dislocation

MRI plays a pivotal role in differentiating these conditions.

Quiz

1. Which of the following best describes the most common site of rupture in a pectoralis major tear?

A. Clavicular head origin
B. Musculotendinous junction
C. Humeral shaft
D. Sternocostal junction

2. Which MRI sequence is most sensitive to soft tissue edema and muscle contusion?

A. T1-weighted imaging
B. Proton density
C. T2 fat-saturated imaging
D. Gradient echo

Answer & Explanation

1. Answer: B. Musculotendinous junction. Explanation: The most frequent site of pectoralis major tear is the musculotendinous junction, where the muscle transitions into tendon, making it structurally vulnerable.

2. Answer: C. T2 fat-saturated imaging. Explanation: T2-weighted fat-saturated sequences best highlight fluid-sensitive pathology such as edema and hemorrhage, making them ideal for evaluating acute muscle tears.

Conclusion

A pectoralis major tear is a serious yet treatable injury, especially among athletic populations. Early recognition, accurate imaging using MRI, and prompt surgical management are key to restoring function and preventing long-term disability. This review aims to assist radiologists, sports medicine physicians, and orthopedic surgeons in identifying and managing this uncommon but important condition.

References

[1] T. ElMaraghy, E. Devereaux, and D. Ravichandiran, "Pectoralis major tears: Diagnosis and management," Clin. Sports Med., vol. 31, no. 2, pp. 233–248, Apr. 2012.
[2] S. A. Zeman, G. Rosenberg, and J. D. Poulos, "Pectoralis major rupture: A case report and review of the literature," Am. J. Sports Med., vol. 7, pp. 343–347, 1979.
[3] J. A. Schepsis, J. J. Grafe, and G. P. Jones, "Rupture of the pectoralis major muscle: Outcome after repair of acute and chronic injuries," Am. J. Sports Med., vol. 28, no. 1, pp. 9–15, Jan. 2000.
[4] R. Kakwani et al., "Pectoralis major ruptures: Surgical repair using suture anchors," Int. J. Shoulder Surg., vol. 1, pp. 56–59, 2007.
[5] M. K. Connell et al., "MR imaging of pectoralis major injuries," Radiographics, vol. 26, no. 5, pp. 1335–1346, Sep.-Oct. 2006.
[6] D. M. White et al., "Clinical and MRI evaluation of pectoralis major tears," Orthop. J. Sports Med., vol. 3, no. 4, pp. 2325–2344, 2015.
[7] M. A. Ritsch, "Pectoralis major tendon rupture in athletes: Surgical repair and outcomes," Oper. Tech. Sports Med., vol. 21, no. 3, pp. 248–254, Jul. 2013.

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