Learning objectives
Knowing the MR anatomy and protocol to optimally scan humeral insertion of the pectoralis maior muscle.
Describe the findings in both complete and partial rupture of the pectoralis muscle tendon
Describe the normal findings in successful postoperative repair of the tendon
Background
Rupture of the pectoralis major muscle is becoming more prevalent due to increasing number of both professional and recreational athletes increase.
Complete rupture typically occurs when the muscle is under full tension and subject to additional stress,
is particularly common in activities that include weight liftingandare seen most often in young,
athletic males.
Patients with a ruptured pectoralis major present in the acute phase,
with pain,
extensive swelling,
and ecchymosis of the anterior chest wall,
axilla,
and medial aspect of the affected arm.
A "pop"...
Imaging findings OR Procedure Details
Anatomy
The pectoralis major muscle is a fanshaped muscle with three origins (clavicular,
sternal and abdominal) separated by a distinct interval.
-The clavicular headforms the anterior lamina of the tendonandarises from the anterior surface of the medial twothirds of the clavicle and upper sternum.
- The sternal head comprises the manubrial head(middle lamina) arising from the mid portion of thesternum and the first-to-fifth costal cartilages.
-Theabdominal head (posterior lamina)arises from the fifth and sixth ribs and the fasciaeof the external oblique and transversus abdominis
muscles...
Conclusion
Pectoralis mayor muscle tendon rupture is an increasing lesion that should be readily diagnosed to allow early surgical specially in young athletic individuals.
Ultrasound and MRI are reliable to depict muscle tendon ruptures and distinguish between partial and compete tendo ruptures
References
1.-Connell et al.Injuries of the Pectoralis MajorMuscle: Evaluation with MR
Imaging(Radiology 210:785-791,
1999)
2.-Lee et al.MR Imaging Assessment of thePectoralis Major Myotendinous Unit: An MR Imaging–AnatomicCorrelative Study with SurgicalCorrelation.AJR 2000;174:1371–1375.
3.- Wolfe et al.
Ruptures of the pectoralis major muscle: an anatomic and clinical analysis.
Am J Sports Med 1992; 20:587–593.
4.-Carrino et al.Pectoralis major muscle and tendon tears:diagnosis and grading using magneticresonance imaging.Skeletal Radiol (2000) 29:305–313
5.-Zvijac et al.Pectoralis Major TearsCorrelation of Magnetic Resonance Imagingand Treatment Strategies.The American Journal of Sports Medicine,
Vol.
34,...