Comparison of clinical outcomes associated with arthroscopic cyst wall preservation or resection in the treatment of popliteal cyst: a systematic review and meta-analysis

Objective Arthroscopy is commonly used to treat popliteal cysts, but the influence of the cyst wall on treatment outcomes remains controversial. The goal of this study was to compare clinical outcomes associated with arthroscopic cyst wall resection versus preservation in patients undergoing treatment for popliteal cysts. Methods We searched the PubMed, Embase, Web of Science, and Cochrane Library databases to identify all relevant articles published as of April 2020. STATA v15.1 was used for all statistical analyses. Relative risk (RR) and corresponding 95% confidence intervals (CIs) pertaining to study outcomes were calculated. Study heterogeneity was evaluated using the I 2 statistic and the χ 2 test, with I 2 > 50% and P < 0.10 as respective significance threshold values. The risk of bias was gauged with the Cochrane Collaboration’s risk of bias tool and the Newcastle–Ottawa Scale (NOS). Results In total, 18 relevant studies were included in this meta-analysis, of which 16 were observational studies and 2 were randomized controlled trials (RCTs). These studies included 573 total patients, of whom 346 underwent arthroscopic cyst resection and 227 underwent arthroscopic cyst preservation. Pooled analyses revealed that clinical outcomes (RR = 0.98, 95% CI 0.94–1.00) and postoperative recurrence rates (RR = 0.90, 95% CI 0.85–0.95) were significantly better among patients that underwent cyst wall resection relative to those that underwent cyst wall preservation (RR = 0, 95% CI 0–0.02 and RR = 0.05, 95% CI 0.02–0.10, respectively). However, complications occurred more often in the cyst wall resection group relative to the cyst wall preservation group (RR = 0.05, 95% CI 0.01–0.12 vs. RR = 0.01, 95% CI 0–0.03). Sensitivity analyses confirmed the stability of these pooled results, and we detected no significant risk of publication bias. Conclusions Relative to cyst wall preservation, popliteal cyst wall arthroscopic resection can yield more satisfactory clinical results and decrease rates of recurrence, but can also increase the incidence of complications. Future prospective studies comparing the outcomes associated with cyst wall resection and preservation will be required to validate our results.