Pectoralis major tendon rupture: a biomechanical analysis of repair techniques

Rupture of the insertion of the pectoralis major muscle to the proximal humerus is becoming a common injury. Repair of these ruptures increases patient satisfaction, strength, and cosmesis, and shortens return to competitive sports. Several repair techniques have been described, but recently many surgeons are using suture anchors. The traditional repair technique uses transosseous sutures, but no study has biomechanically compared the strength of these two repair techniques in human cadavers. Twelve fresh-frozen human shoulder specimens were dissected. The pectoralis major tendon insertion was cut from the bone and repaired using one of the two repair techniques: specimens were randomly assigned to transosseous trough with suture tied over bone versus four suture anchors. The fixation constructs were pulled to failure at 4 mm/s on a materials testing system. The mean ultimate failure load of the transosseous repairs was 611 N and the mean ultimate failure load of the suture anchor repair was 620 N. The mean stiffness of the transosseous repair was 32 and 28 N/mm for the suture anchor group. We found no statistically significant difference between these two repair techniques.