Impact of Significant Coracoid Graft Resorption on Clinical Outcomes After Arthroscopic Latarjet Procedure: Development and Validation of a Refined Classification System for Coracoid Bone Graft Resorption

BACKGROUND: The clinical impact of coracoid graft resorption after the Latarjet procedure has been controversial and likely underestimated. PURPOSE: To (1) develop and validate a refined classification system-coracoid graft resorption based on degree and location (CRDL); and (2) correlate clinical and radiological outcomes with the CRDL classification system. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Between January 2015 and December 2018, 63 patients who underwent the arthroscopic Latarjet procedure were evaluated with computed tomography imaging preoperatively, immediately postoperatively, and at a minimum 5-year follow-up. According to the resorption location, the coracoid graft resorption was classified as grade 0 (no resorption), grade 1 (resorption on the proximal-medial and/or distal-medial part), grade 2 (resorption on the proximal-lateral part with no resorption on the distal-lateral part), and grade 3 (resorption on the distal-lateral part). Resorption severity was categorized as mild (grades 0 and 1) and severe (grades 2 and 3). The incidence, classification, and location of graft resorption were described. Intrarater and interrater reliability were calculated. Correlations between the classification and clinical and radiological outcomes were analyzed. RESULTS: After a mean follow-up of 85.3 months, coracoid graft resorption was observed in 84.1% of cases: grade 0 in 15.9%, grade 1 in 47.6%, grade 2 in 30.2%, and grade 3 in 6.3%. Mild and severe resorption were found in 63.5% and 36.5% of patients, respectively. Resorption mainly occurred on the proximal-medial part of the graft. Intra- and interrater reliability of the classification system were both almost perfect (κ = 0.865 and 0.822, respectively). Significant differences were found in the postoperative American Shoulder and Elbow Surgeons (ASES) and visual analog scale for pain (VAS) scores among different grades and between mild and severe resorption. Correlation and multivariable regression analyses identified higher-grade graft resorption as a risk factor for worse postoperative ASES and VAS scores. CONCLUSION: CRDL classification is a reliable and clinically relevant classification system for coracoid graft resorption evaluation. Application of the CRDL system reveals that while high-grade resorption is a significant risk factor for postoperative shoulder pain, it has no major impact on shoulder function or stability.