Glenoid rim fracture through anchor points after arthroscopic Bankart repair for shoulder instability.

PURPOSE: We studied the incidence of postoperative glenoid rim fractures and analysed the relationships of glenoid rim fracture with osteolysis, fracture pattern, number of anchors and postoperative activity after arthroscopic Bankart repair with suture anchor fixation.

METHODS

Among 570 patients of the Bankart repair group, nine patients who had undergone revision arthroscopy for glenoid rim fracture after initial Bankart repair with at least two years post-revision follow-up were enrolled. Mean age was 28.8 years (range, 18-49 years), and mean follow-up was 36.4 months (range, 25-64 months). The mean time from Bankart repair to failure of initial surgery following trauma was 27.3 months (range, four to-84 months). Initial suture anchors were made of bioabsorbable composites (poly-D-L-lactic acid, PDLLA) without ceramic osteo-filler (seven cases) and metals (two cases). PDLLA without ceramic osteo-filler suture anchors were used for revision surgery. We reviewed 570 patients for relationship between osteolysis and glenoid rim fracture.

RESULTS

Five patients including three and two with bioabsorbable and metal suture anchors, respectively, experienced glenoid rim fracture at more than two years postoperatively. Osteolysis around initial suture anchors groups showed higher glenoid rim fracture incidence compared with the control group (odd ratio =4.186 [95 % CI, 1.108-15.818]; p = 0.037).

CONCLUSIONS

Osteolysis related to insertion of metal or PLDDA suture anchors may lead to glenoid rim fracture. Remnant metal or bioabsorbable suture anchors without ceramic composite could be a stress riser at two years postoperatively.