1. Does a Critical Rotator Cuff Tear Stage Exist? by Joo Han Oh, Bong Jae Jun, Michelle H. McGarry, and Thay Q. Lee J Bone Joint Surg Am Volume 93(22):2100-2109 November 16, 2011 ©2011 by The Journal of Bone and Joint Surgery, Inc.

2. Custom shoulder testing system. Joo Han Oh et al. J Bone Joint Surg Am 2011;93:2100-2109 ©2011 by The Journal of Bone and Joint Surgery, Inc.

3. Front view of custom shoulder testing system, demonstrating 30° of shoulder abduction with a 2:1 ratio of glenohumeral to scapulothoracic abduction. Joo Han Oh et al. J Bone Joint Surg Am 2011;93:2100-2109 ©2011 by The Journal of Bone and Joint Surgery, Inc.

4. Rotator cuff tear progression based on footprint anatomy. Joo Han Oh et al. J Bone Joint Surg Am 2011;93:2100-2109 ©2011 by The Journal of Bone and Joint Surgery, Inc.

5. The abduction capability at each tear progression stage with increasing middle deltoid loading from 30 N to 70 N in increments of 10 N (*p < 0.05 vs. intact, +p < 0.05 vs. Joo Han Oh et al. J Bone Joint Surg Am 2011;93:2100-2109 ©2011 by The Journal of Bone and Joint Surgery, Inc.

6. The humeral head apex anterior-posterior position relative to the intact condition for each tear stage at 30° of abduction with rotator cuff and deltoid loading (*p < 0.05 vs. intact). Joo Han Oh et al. J Bone Joint Surg Am 2011;93:2100-2109 ©2011 by The Journal of Bone and Joint Surgery, Inc.

7. Anterior-posterior and superior-inferior position of humeral head apex at each humeral rotation angle in each cuff tear stage at 60° of abduction with rotator cuff, deltoid, pectoralis major, and latissimus dorsi muscle loading condition. Joo Han Oh et al. J Bone Joint Surg Am 2011;93:2100-2109 ©2011 by The Journal of Bone and Joint Surgery, Inc.

8. Effect of deltoid, pectoralis major, and latissimus dorsi muscle-loading on position of the humeral head apex at 0° of abduction with Stage-IV rotator cuff tear. Joo Han Oh et al. J Bone Joint Surg Am 2011;93:2100-2109 ©2011 by The Journal of Bone and Joint Surgery, Inc.

9. Balanced force couple. Joo Han Oh et al. J Bone Joint Surg Am 2011;93:2100-2109 ©2011 by The Journal of Bone and Joint Surgery, Inc.

10. Unbalanced force couple. Joo Han Oh et al. J Bone Joint Surg Am 2011;93:2100-2109 ©2011 by The Journal of Bone and Joint Surgery, Inc.