Abstract
Purpose: The purpose of our work was to study the effects of sequential arthroscopic section of the anterior capsule of the shoulder joint using an experimental model of retractile capsulitis induced by heat treatment.
Material and methods: Twelve cadaver shoulders were studied. Passive mobility was initially normal. Anterior capsule retraction was first created under arthroscopic control (Arthrocare® generator, power 2). Twelve programmed sequential sections were then performed successively using the thermal probe (Arthrocare®, power 9) on: the coracohumeral ligament (CHL) and the superior glenohumeral ligament (SGHL), the middle gleno-humeral ligament (MGHL), the inferior glenohumeral ligament (IGHL), and the intra-articular portion of the subscapular muscle tendon (SST). The posterior capsule was not studied. At each step, motion was measured independently by two operators. At the end of the sequence, the articulation was opened to verify the sections as was the absence of any injury to noble structures.
Results: Measures were reproducible (mean difference 5° between two series). The sections were correctly achieved. Macroscopically, there were no injuries to noble structures. The role of the different elements studied were as follows: — rotator interval (CHL, SGHL): gain in RE1 (mean 40°) and RE2 (mean 35°) (greater than loss during retraaction; — IGHL: gain in elevation (mean 33°); — IGHL and rotator interval: potentialisation of gain in FE2 (mean 41°) and elevation (mean 50°); — MGHL: moderate increase in external rotation at 45° antepulsion and elevation (mean 20°); —SST: discrete gain in RE1 (10°) but risk of dislocation (n=1).
Discussion: Our model was reproducible. Section of the anterior capsule by a thermal method did not produce macroscopic injury to neighboring tissues. Our study pointed out the preeminent importance of sectioning the rotator interval for recovering external rotation. This section, combined with section of the IGHL has a potentialsing effect. The limitation of our study is the absence of examination of the posterior capsule.
The abstracts were prepared by Docteur Jean Barthas. Correspondence should be addressed to him at Secrétariat de la Société S.O.F.C.O.T., 56 rue Boissonade, 75014 Paris.
