Fate of coracoid grafts after the Latarjet procedure: will be analogous to the original glenoid by remodelling.

PURPOSE: To evaluate the location, magnitude, and change over time of osteolysis of coracoid grafts after Latarjet procedure.

METHODS: This is a retrospective study of 54 patients (55 shoulders) who underwent the Latarjet procedure. Three-dimensional computed tomography (CT) scans were performed preoperatively, immediately postoperatively, and at follow-up (mean 7.7 and 31.7 months postoperative). "En face" views of the glenoid, size of glenoid defect and changes in the glenoid surface area postoperatively were measured relative to the area of an assumed outer-fitting circle. On the oblique sagittal planes, location and subsequent severity of osteolysis of the graft at follow-up were documented.

RESULTS: The mean glenoid surface area increased significantly from 79.7 ± 4.8% of the original circle preoperatively to 111.3 ± 8.0% immediately postoperatively. At 7.7 and 31.7 months of follow-up, glenoid surface area decreased to 102.2 ± 6.0% and 100.3 ± 5.3%, respectively. Osteolysis occurred on the outer side of the graft in all cases, but did not occur on the inner side. Maximum osteolysis was observed in the superior third of the graft (78.5 ± 17.1%), followed by the middle third (15.8 ± 10.4%), and the inferior third (8.0 ± 5.1%). No significant difference in magnitude of osteolysis was observed between 7.7 and 31.7 months of follow-up.

CONCLUSION: Osteolysis of the grafted coracoid mainly occurred on the outer side of the superior portion, resulting in reshaping of the rectangular shape of graft coracoids after Latarjet procedure. Coracoid graft remodelling was almost completed approximately 8 months postoperatively to reach the original glenoid dish with no further changes thereafter. These results may help surgeons to understand changes of grafts after the surgery.

LEVEL OF EVIDENCE: IV.