Does Labral Reconstruction Prevent Osteoarthritis After Posterior Shoulder Instability: A Population-Based Study

OBJECTIVES: Diagnosis of and treatment for posterior shoulder instability (PSI) has improved with advances in surgical technique and radiographic imaging. It is unknown if PSI, or surgical measures to correct PSI, affect the progression of osteoarthritis in the glenohumeral joint. The purpose of this study is to evaluate the effect of posterior capsulolabral reconstruction (PCLR) and demographic risk factors on the rate of radiographic progression of osteoarthritis in shoulders with PSI. METHODS: The study population included 115 patients (14 females, 101 males) diagnosed with PSI between January 1994 and July 2012 with an average follow up of 12.5years (range 5-23). Medical records were reviewed to evaluate patient demographics, surgical intervention, and radiographic progression of osteoarthritis. Kaplan Meier survival was used to estimate survival and Cox models were used to examine associations with osteoarthritis progression. RESULTS: Overall, 16/115 (14%) patients had radiographic progression of glenohumeral arthritis with 5-year survival at 88.3% (95% CI 79.7%-97.3%). Age ≥30 at the time of instability was associated with arthritis progression (p<0.05). The number of previous dislocations, sport, and gender each did not affect progression (p>0.05). PCLR with at least one anchor along the posterior glenoid rim was performed in 56/115 (48%) of patients. There was no difference in the rate of radiographic arthritic progression in those who underwent PCLR and those who did not (7/56, 13% vs 10/59, 17%, p>0.05). One male patient who underwent PCLR progressed to end-stage arthritis, necessitating a shoulder arthroplasty at age 53. CONCLUSION: Radiographic progression of glenohumeral arthritis occurred 14% of patients with PSI. Age ≥30 at the time of initial instability was associated with radiographic progression of glenohumeral arthritis.