Initiatory biomechanical study on humeral head migration after coracoacromial ligament cut.

OBJECT: To design and evaluate the strength of muscles in preventing humeral head migration after acromioplasty by biomechanical research on cadaver models.

METHODS

Six fresh shoulder cadavers were studied. The coracoacromial ligament cut model was prepared in five shoulders for the study. Different forces were applied to the head of humerus with designed strengthened force on rotator cuff muscles. The results were calculated with SPSS software.

RESULTS

The anterior and superior pulling force caused obvious migration of humeral head in coracoacromial ligament cut model; after strengthening the rotator cuff muscles, especially the supraspinatus and subscapular muscle, the humeral head migration was reduced.

CONCLUSION

Modified acromioplasty with supraspinatus and subscapular muscle, strengthened in our experiment, helped to control the migration of humeral head.