0 Item(s)
Reverse Total Shoulder Arthroplasty for Rotator Cuff Tear Arthropathy
The rotator cuff muscles provide a dynamic and balanced force couple to center the humeral head on the glenoid during all ranges of shoulder motion. This arrangement allows the deltoid and larger muscles to efficiently generate a rotary force to elevate and rotate the arm with power and direction. With a massive rotator cuff tear, the balanced axial and coronal force couples between the rotator cuff and deltoid are lost, and the deltoid loses the ability to generate effective elevation or rotational torque. Consequently, the deltoid pulls the humerus proximally, eventually resulting in anterior-superior glenohumeral instability and a pathologic articulation between the humeral head and acromion. Massive irreparable rotator cuff tear inciting the development of glenohumeral arthritis and eventual humeral head osteonecrosis was first described in 1983, and this phenomenon was termed rotator cuff tear arthropathy. In some instances, a massive irreparable rotator cuff tear can occur without glenohumeral arthritis; however, this chapter focuses on the classic description of rotator cuff tear arthropathy.