Comparison of outcomes in retrospective vs. prospective Latarjet studies for shoulder instability.

BACKGROUND: The method of data collection can introduce bias and influence data results. The purpose of this study was to determine the difference in outcomes in retrospective vs. prospective studies investigating Latarjet procedure for shoulder instability.

METHODS: PubMed, Embase, and Scopus were queried for studies investigating outcomes following Latarjet procedure for shoulder instability. Inclusion criteria were (1) described study design, (2) was in English, (3) had full text available. Exclusion criteria included systematic reviews, meta-analyses, case reports, abstracts, and presentations. For each study, year, study design, Coleman Methodology Score, follow-up time, intraoperative complications, postoperative complications, rate of postoperative instability events, return to play rate, and revision rate were collected. A Welch's 2-sample t-test or Mann-Whitney U test was used to compare between prospective and retrospective studies where applicable. Statistical significance was defined as a P value <.05.

RESULTS: A total of 78 studies were included for analysis. There were 24 prospective studies, consisting of 1,482 patients and 1,493 shoulders, and 54 retrospective studies, consisting of 4,478 patients and 4,766 shoulders. Retrospective studies had significantly longer follow-up time (5.67 years vs. 3.96 years, P = .034). There were significantly higher rates of postoperative instability (3.02% vs. 1.24%, P = .007), dislocations (2.51% vs. 0.76%, P = .009), complications (11.42% vs. 4.40%, P = .002), and return to play rates (91% vs. 28%, P = .024) in retrospective studies compared to prospective studies. There were no significant differences in intraoperative complications, postoperative subluxation, or revision rates (P > .05).

CONCLUSION: Retrospective studies report more postoperative complications and instability in Latarjet studies. This may be related to the significantly increased follow-up time in retrospective studies compared to prospective studies, but may also be confounded by recall bias or inconsistencies in data collection. It is important to account for potential biases or confounders when designing or evaluating retrospective studies. Standardized criteria for reporting complications would help improve reliability and generalizability of Latarjet studies.