We investigated the useful biomaterials for the purpose of the regeneration of the soft tissues of the traumatic instability of the shoulder joint. Based on experimental study, the polyglycolic acid sheet (PGA sheet) was the most suitable material for the regeneration of the soft tissues of the traumatic instability of shoulder joint. We clinically used the PGA sheet for the regeneration of the anteroinferior glenohumeral ligament complex (AIGHL complex) in cases of traumatic instability of the shoulder joint. From 2000, we performed arthroscopic Bankart repair on 330 traumatic instability cases. Out of the 330 cases, we experienced ten cases whose capsule and AIGL complex became thin compared with uninjured cases. 7 cases were male, 3cases were female. The average age was 25.6 years old. The average times of dislocation were 5.8 times. We grafted the PGA sheet to the injured site arranging the size of the graft to adapt to the injured site. We evaluated the clinical results using JSS shoulder instability score. The average JSS shoulder instability score improved from 45.6 points to 91.2 points postoperatively. We did not experience redislocation cases. There was not any difference in the external rotation compared with the uninjured side. There were few reports of the clinical usage of biomaterials for the regeneration of the soft tissues. We applied the PGA sheet for the purpose of the regeneration of the AIGHL complex. The clinical results were preferable.
