Pectoralis Major- Anatomy and Surgical Considerations

Courtesy: Prof Nabile Ebraheim, University of Toledo, Ohio, USA

 

Anatomical  &  surgical consideration of Pectoralis Major

• Pectoralis major extends from Sternum to humerus
• Consists of 2 heads- clavicular head from clavicle to upper humerus
• Sternocostal head – from sternum+first rib Through sixth rib to upper humerus
• Inserted into lateral lip of bicipital groove
• Innervation- medial & lateral pectoral nerve
• Action: Adduction + internal rotation of arm

–          Tear occurs in young weight lifters

Symptoms-   pain around shoulder, loop feeling on bench press, discoloration + burning sensation over pectoralis major+ axilla, lose of contour of axillary fold, palpable defect

Investigation: MRI to differentiate between  complete & partial tear & to locate the tear.

Treatment: reinsertion of tendon into shaft of humerus lateral to biceps groove

Chronic case: tendon graft

POLAND SYNDROME:

• Unilateral chest wall hypoplasia due to the absence of sternocostal head of  Pectoralis major
• absence of metacarpals+phalanges
• hypoplasia of hand n forearm
• syndactyly

Pectoralis minor:

• Origin: surface of superior margin of 3,4 n 5 ribs
• Insertion:medial border of coracoid process of scapula
• Innervation: medial pectoral nerve
• Action: stabilizes scapula by drawing scapula inferiorly and anteriorly