Pectoralis Major Tendon Rupture

By admin Last updated Feb 20, 2024

Ovid: 5-Minute Orthopaedic Consult

Editors: Frassica, Frank J.; Sponseller, Paul D.; Wilckens, John H.

Title: 5-Minute Orthopaedic Consult, 2nd Edition

> Table of Contents > Pectoralis Major Tendon Rupture

Pectoralis Major Tendon Rupture

Mark Clough MD

John H. Wilckens MD

Basics

Description

The pectoralis major is an adductor, flexor, and internal rotator of the humerus.
Muscular origins are on the clavicle, sternum, ribs, and external oblique fascia.
The insertion is on the crest of the lateral aspect of the midhumerus.
The muscle twists so that the lower fibers insert highest on the humerus.
Anatomic classification system (1):
- Type I: Muscle strain, microscopic tear
- Type II: Partial tear
- Type III: Complete tear

General Prevention

Avoid extreme weightlifting, including bench press and butterfly curls.
Avoid anabolic steroid use.

Epidemiology

Usually occurs in male power athletes 20–40 years old (2)
Can occur in the elderly (>65 years old) (3)

Incidence

Unknown

Prevalence

Unknown

Risk Factors

Anabolic steroid use
Power lifting, weightlifting

Pathophysiology

Depends on the location of the rupture

Etiology

Strains and partial tears:
- Most common forms of injury
- Involve the muscle belly
- Partial ruptures generally occur at the musculotendinous junction or are intramuscular.
Total rupture:
- Rare injury
- The mechanism of injury is usually a
  sudden forceful overload of an eccentrically contracted muscle, such as
  during a weightlifter’s bench press.
- Usually occurs as avulsion at or near the muscular insertion on the humerus

Diagnosis

Signs and Symptoms

History

Patients often present with a history of sudden onset of severe arm and shoulder pain associated with the time of injury.
- Audible “snap” or “pop” during injury
- Limited ROM
- Local swelling
- Ecchymosis

Physical Exam

Disruption in the anterior axillary contour
A thin anterior axillary fold or a sulcus may be seen at the deltopectoral groove
A defect may be palpable.
A bulging may be seen at the muscular origins when a patient is asked to tension the muscle.

Tests

Manual muscle testing of adduction and internal rotation will show weakness.

Imaging

Plain radiographs:
- Always start with plain radiographs to rule out any bony pathology.
- Bony avulsions also may appear on plain radiographs.
Ultrasonography:
- Can help locate tears and help define diagnosis when diagnosis is unclear clinically
- Safe and cost-effective, but user-dependent
MRI:
- Has been used to diagnose and localize muscle tears
- Can be helpful in the acute setting when physical examination is limited by swelling and pain
- Is now the imaging modality of choice
  because it can distinguish acute and chronic tears and can determine
  the exact location and size of the tear

Diagnostic Procedures/Surgery

The diagnosis of a pectoralis major muscle tear is generally a clinical one.
For purposes of surgical planning, the location of the tear should be localized with MRI.

Pathological Findings

Torn muscle and tendon fibers may be visualized at time of surgery.
Muscle attenuation and atrophy can be seen in the elderly population.

Differential Diagnosis

Pectoralis major tendon rupture
Pectoralis major tendon strain
Proximal humerus fracture
Coracoid avulsion fracture

Treatment

Treatment options include operative and nonoperative management.

Initial Stabilization

The patient should be stabilized initially in a sling and/or swath.

General Measures

Nonoperative treatment:
- Includes rest, immobilization, analgesia, and ice.
- Can lead to a functional result but will not restore full preinjury strength or cosmetic appearance
- Regard the patient as an individual when considering treatment options.
  - An elderly patient of limited functional status may prefer nonoperative treatment
  - A professional athlete may require surgery to have the best chance of returning to the preinjury level of activity.

Activity

The patient’s activity status is dictated by whether nonoperative or operative therapy is chosen.

Special Therapy

Physical Therapy

After the acute injury, patients may begin physical therapy.
Strengthening exercises may start once painless ROM is achieved and the hematoma has resolved.

Medication

NSAIDs
Narcotics may be necessary for severe pain or postsurgical pain.

Surgery

Surgical treatment is based on anatomic repair of the muscle.
The literature supports anatomic surgical
repair as resulting in the best outcomes (as measured by return of
strength, regaining preinjury activity status, and return to work).
- In a review article (4),
  patients who underwent surgical repair had decreased pain and a higher
  rate of return to preinjury strength and activity than did those
  treated nonoperatively.
- Hanna et al. (5) compared measures of strength and subjective functional outcomes in complete tears treated surgically or nonsurgically.
  - Surgical treatment resulted in greater return of muscular strength than did nonoperative treatment.
  - Delays in surgery make surgical repair more difficult, but a good outcome is still possible.
The specific type of surgical repair depends on the classification of the tear (6).
- Tears at the musculotendinous junction require direct suturing of the ruptured ends.
- Ruptures at the tendon or at the
  insertion site require reapproximation of the remaining tendon to the
  bony insertion via drill holes, direct suture, or bone anchors.
- Contracted tendon tears may require interpositional tendon grafting.

P.319

Follow-up

Disposition

The patient is immobilized for 4–6 weeks
with the shoulder adducted, internally rotated, and slightly flexed,
allowing Codman exercises only.
ROM exercises are initiated after the immobilization period.
Once full ROM has been achieved, usually 12–14 weeks after surgery, patients may begin active strengthening.

Prognosis

Generally good
Patients can expect to regain motion and strength, but the degree depends on the type of treatment.
- Nonoperative treatment often leads to loss of adduction strength, shoulder flexion, and internal rotation (7).

Complications

Complications from pectoralis major tendon ruptures are rare.
- Rerupture
- Hematoma infection
- Heterotopic ossification
- Unable to return to prerupture strength

Patient Monitoring

Patients should be seen 10–14 days after surgery for wound check and suture removal.
As therapy progresses, patients should be seen every 2–3 weeks to monitor strength and ROM.

References

1. Tietjen R. Closed injuries of the pectoralis major muscle. J Trauma 1980;20:262–264.

2. Petilon J, Carr DR, Sekiya JK, et al. Pectoralis major muscle injuries: evaluation and management. J Am Acad Orthop Surg 2005;13:59–68.

3. Beloosesky Y, Hendel D, Weiss A, et al. Rupture of the pectoralis major muscle in nursing home residents. Am J Med 2001;111:233–235.

4. Bak K, Cameron EA, Henderson IJP. Rupture of the pectoralis major: a meta-analysis of 112 cases. Knee Surg Sports Traumatol Arthrosc 2000;8:113–119.

5. Hanna CM, Glenny AB, Stanley SN, et al. Pectoralis major tears: comparison of surgical and conservative treatment. Br J Sports Med 2001;35: 202–206.

6. Dodds SD, Wolfe SW. Injuries to the pectoralis major. Sports Med 2002;32:945–952.

7. Aarimaa V, Rantanen J, Heikkila J, et al. Rupture of the pectoralis major muscle. Am J Sports Med 2004;32:1256–1262.

Additional Reading

Quinlan JF, Molloy M, Hurson BJ. Pectoralis major tendon ruptures: when to operate. Br J Sports Med 2002;36:226–228.

Miscellaneous

Codes

ICD9-CM

840.8 Sprains and strains of joints and adjacent muscles, other specified sites of shoulder and upper arm

FAQ

Q: How long after pectoralis tendon rupture can it be repaired successfully?

A:
Generally, repair in the 1st few weeks to months allows for a simple
repair of the ruptured tendon without much difficulty. After 6 months,
considerable scarring around the tendon and retraction of the muscle
has occurred, making a primary repair difficult. In those cases, an
Interpositional tendon graft can bridge the gap with good clinical
results.