This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Letters to the Editor: Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when Letters to the Editor are posted
Right arrow Alert me if a correction is posted
Services
Right arrow E-mail this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My File Cabinet
Right arrow Download to citation manager
Right arrowReprints and Permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by LIU, J.
Right arrow Articles by AN, K.-N.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by LIU, J.
Right arrow Articles by AN, K.-N.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us   Add to Technorati  
What's this?
The Journal of Bone and Joint Surgery 80:853-9 (1998)
© 1998 The Journal of Bone and Joint Surgery, Inc.

Biomechanical Effect of Medial Advancement of the Supraspinatus Tendon. A Study in Cadavera*

JAIN LIU, M.D.{dagger}, RICHARD E. HUGHES, PH.D.{ddagger}, SHAWN W. O'DRISCOLL, M.D., PH.D.{ddagger} and KAI-NAN AN, PH.D.{ddagger}, ROCHESTER, MINNESOTA

Investigation performed at the Division of Orthopedic Research, Mayo Clinic and Mayo Foundation, Rochester

During the repair of some rotator-cuff tears, the torn tendon cannot be freed up adequately to permit reattachment at its original anatomical site of insertion. An option is to advance the site of insertion medially and reattach the tendon to a trough in the sulcus or to the humeral head. The biomechanical effects of such medial advancement on the moment arm of the supraspinatus muscle during glenohumeral elevation were studied in ten fresh-frozen shoulders from cadavera. Medial advancement of the site of insertion of the supraspinatus tendon was simulated by the placement of suture anchors in the sulcus of the proximal part of the humerus at points three, ten, and seventeen millimeters medial to the junction of the supraspinatus tendon and the bone. These distances were chosen not because they represent clinical options but because the large range allowed biomechanical study of medial advancement. Nylon lines were attached to the suture anchors and were passed back through an eyehook at the midpoint of the supraspinatus muscle. The excursion of each line was measured as the humerus was elevated, and the moment arm was estimated from the joint angle and excursion data with use of the principle of virtual work. Three and ten millimeters of medial advancement of the tendon (attachment in the sulcus) had a minimum (non-significant) effect on the moment arm during elevation compared with the value determined for the intact condition. However, seventeen millimeters of medial advancement was found to reduce the moment arm significantly (p < 0.05). CLINICAL RELEVANCE: Our study of cadavera indicates that a limited amount of medial advancement (as much as ten millimeters) is acceptable from a biomechanical point of view, although the clinical maximum is dictated by other clinical factors.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Technorati Technorati    What's this?