Immediate effect of thermal capsulorrhaphy on glenohumeral joint mobility

Objectives. To evaluate the effects of anterior thermal capsulorrhaphy of the glenohumeral joint by monitoring changes of magnitudes of the anterior and posterior displacements of the humeral head and ranges of motion of abduction and rotation in fresh cadaver shoulders. Design. Single session repeated-measures design. Background. Following thermal shrinkage anterior and posterior displacements of the head of humerus were decreased. However, no studies were focused on the ranges of motion of abduction and rotation of the shoulder joint immediately. The mobility of abduction and rotation are also important indexes for glenohumeral function. Methods and measures. Nine fresh frozen shoulder specimens were used. The dorsal and ventral displacements of humeral head and ranges of motion of abduction and rotation of glenohumeral joint before and after thermal capsulorrhaphy were performed and monitored. Changes after thermal treatment in these linear and angular displacement variables were calculated as outcome measures. Results. After anterior thermal capsulorrhaphy, significant (P<0.001) decreases were found in displacements (−1.80 mm in dorsal direction and −1.24 mm in ventral direction), rotation range of motion (−3.93° in lateral rotation and −2.60° in medial rotation), and abduction range of motion (−3.15°). Conclusions. The results from cadaveric experiments showed that anterior thermal capsulorrhaphy immediately reduced the dorsal and ventral displacements and ranges of abduction and rotation of glenohumeral joint by a small amount.