Bone defect-induced alteration in glenoid articular surface geometry and restoration with coracoid transfer procedures: a cadaveric study.

BACKGROUND

This study analyzed the alteration in glenoid articular geometry with increasing anterior bone loss, as well as its subsequent correction with 2 modifications of the Latarjet procedure.

METHODS

Anterior defects were simulated by creating glenoid osteotomies (10%, 20%, 30%, and 40%), and defects were reconstructed using 2 Latarjet modifications (classic and congruent arc). A total of 108 computed tomography scans were performed (1) on intact scapulae (n = 12), (2) after each bone defect (n = 48), and (3) after each reconstruction (n = 48). Glenoid parameters (width, area, arc length, and version) were analyzed on computed tomography scans. Statistical analysis was used to determine significant differences between intact, deficient, and reconstructed glenoids.

RESULTS

All parameters were reduced with every 10% defect increment (mean change in width, 2.5 mm; area, 64 mm; version, 2.2°; and arc length, 2.2 mm). Width correction with the classic Latarjet procedure was not statistically significant in 30% and 40% defects. Area correction in 30% defects was not significant with the classic Latarjet procedure and was significantly undercorrected in 40% defects. Version correction was not significant after the classic Latarjet procedure in 20%, 30%, and 40% defects. Arc-length correction was not significant in 20% and 30% defects with the classic Latarjet procedure and was significantly undercorrected in 40% defects. The congruent-arc Latarjet procedure overcorrected glenoid parameters in all defects; however, area and arc length were not significantly different from intact glenoids in 40% defects (P < .05).

CONCLUSION

Glenoid articular geometry is progressively altered with a sequential increase in anterior bone defects from 0% to 40%. The classic Latarjet procedure provided significant correction in bone defects of 10% and 20%. The congruent-arc Latarjet procedure restored and overcorrected most parameters even in 40% glenoid defects.