Subacromial spacer

Abstract

Implantation of the biodegradable spacer in the subacromial space is one of the surgical treatment options in patients with massive irreparable rotator cuff tear. These patients usually present with diverse clinical picture of pain, loss of range of motion (ROM), and impaired shoulder function. Patients with shoulder dysfunction and predominant pain symptom are best candidates for this kind of treatment. The arthroscopic surgical insertion of the implant in the subacromial space is reported in many articles to be safe, simple, and with low complication rate. The important biomechanical effects of the subacromial spacer implantation are to restore force couples of the glenohumeral joint in coronal plane, to maintain humeral head in the stable position during dynamic movement, and to decrease subacromial friction. It is still not well explained why the results last over the period of spacer biodegradation and even improve over time as it was shown in several clinical reports. Recently, biodegradable subacromial spacer is also used as additional support and protection in repaired massive rotator cuff tears since the spacer can decrease humeral head upward migration, improve the humeral head position, and restore functional abduction force similar to the intact condition.