Abstract
BACKGROUND: There has been increased emphasis in orthopaedics on high-quality prospective research to provide evidence-based treatment guidelines, particularly in sports medicine/shoulder surgery. The external validity of these studies has not been established, and the generalizability of the results to clinical practice in the United States is unknown. HYPOTHESIS: Comparison of patient demographics in major prospective studies of arthroscopic sports and shoulder surgeries to patients undergoing the same procedures in the National Surgical Quality Improvement Program (NSQIP) database will show substantial differences to question the generalizability and external validity of those studies. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: This study utilized patients undergoing arthroscopic anterior cruciate ligament reconstruction (ACLR), meniscectomy (MX), rotator cuff repair (RCR), and shoulder stabilization (SS) from the NSQIP database (2005-2013). Two prospective studies (either randomized controlled trials or, in 1 case, a major cohort study) were identified for each of the 4 procedures for comparison. Demographic variables available for comparison in both the identified prospective studies and the NSQIP included age, sex, and body mass index (BMI). RESULTS: From the NSQIP database, 5576 ACLR patients, 18,882 MX patients, 7282 RCR patients, and 993 SS patients were identified. The comparison clinical studies included cohort sizes as follows: ACLR, n = 121 and 2683; MX, n = 146 and 330; RCR, n = 90 and 103; SS, n = 88 and 196. Age differed significantly between the NSQIP and the patients in 6 of the 8 prospective clinical studies. Sex differed significantly between the NSQIP and the patients in 7 of the 8 prospective clinical studies. BMI differed significantly between the NSQIP and the patients of all 4 of the prospective clinical studies that reported this demographic variable. CONCLUSION: Significant differences exist for patient age, sex, and BMI between patients included in major sports medicine/shoulder prospective studies and corresponding patients undergoing the same procedures in a nationwide database of academic and community centers in the United States. Future work is needed to understand whether major prospective clinical studies-frequently performed in high-volume, specialized practices-are truly indicative of the types of patients treated and expected results in the general orthopaedic practice. This study additionally argues for the importance of initiating a national registry dedicated to patients undergoing orthopaedic procedures in the United States.