There are two purpose of this study, first is to find whether arthroscopic rotator cuff repair is changing the appearance of supraspinatus muscle atrophy in each and every patient. Second, is to find how much approximate change one can expect depending on age and tendon retraction

Retrospective review of 209 patients having both preoperative and immediate postoperative MRI done. Both preoperative and immediate postoperative occupancy ratio calculated and from that change in occupancy ratio calculated for each and every patient. Patient were divided in two major group according to age that is <60 years and >60 years and 3 subgroups of mild, moderate and severe depending on preoperative supraspinatus tendon retraction on coronal view of MRI. Postoperative occupation ratio was compared with preoperative occupation ratio within the subgroups and change in occupation ratio was used for comparison between the subgroup. Change in occupation ratio was also used for comparison between 2 major groups

Inclusion Criteria:

1. Patients with degenerative rotator cuff tear who underwent single-row arthroscopic rotator cuff repair in our hospital.
2. Patients with preoperative MRI and postoperative MRI within 1 week of surgery in our hospital.
3. Patients with minimum grade 1 supraspinatus atrophy in preoperative MRI.

Exclusion Criteria:

1. Patients with preoperative MRI from outside hospital.
2. Patients with isolated subscapularis tear.
3. Patients with previous operation on the same shoulder joint.
4. Patients with MRI images that were not usable due to poor quality or absence of appropriate Y-view.

209 patients with degenerative rotator cuff tear who underwent single-row arthroscopic rotator cuff repair between March 2012 and April 2015 in CM hospital

Sharing of data on the website is against the policy of IRB Korea