Risk factors for unexpected admission following arthroscopic and open treatment of shoulder instability: a national database study of 11,230 cases

BACKGROUND: Shoulder instability procedures have low morbidity; however, complications can arise that result in readmission to an inpatient healthcare facility. The purpose of this study is to identify the demographics and risk factors associated with unplanned 30-day readmission and reoperation following arthroscopic and open treatment for shoulder instability. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was queried to find patients who underwent shoulder instability surgery from 2015 to 2019. Independent sample Student t-tests, chi-square, and (where appropriate) Fisher’s exact tests were used in univariate analyses to identify demographic, lifestyle, and perioperative variables related to 30-day readmission and reoperation following repair for shoulder instability. Multivariate logistic regression modeling was subsequently performed. RESULTS: Of the 11,230 cases included in our sample, only 0.54% were readmitted, and 0.23% underwent reoperation within the 30-day postoperative period. Multivariate logistic regression modeling confirmed that the following patient variables were associated with statistically significantly increased odds of readmission and reoperation: open repair, congestive heart failure (CHF), and hospital length of stay. CONCLUSIONS: Unplanned 30-day readmission and reoperation after shoulder instability surgery is infrequent. Patients with American Society of Anesthesiologists class II, CHF, longer than average hospital length of stay, or an open procedure have higher odds of readmission than patients without those factors. Patients who have CHF, longer than average hospital length of stay, and open surgery have higher odds of reoperation than others. Arthroscopic procedures should be used to manage shoulder instability, if possible. LEVEL OF EVIDENCE: III.