Systematic review and meta-analysis of studies comparing cyst wall preservation against cyst wall resection during arthroscopic popliteal cyst decompression

The optimal arthroscopic management for popliteal cyst decompression remains uncertain, with ongoing debate between preserving the cyst wall or completely removing it. The purpose of this study is to compare the outcomes and complications of arthroscopic popliteal cyst decompression with cyst wall preservation and cyst wall resection.

A systematic review adhering to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines was conducted. It encompassed studies that focused on arthroscopic popliteal cyst decompression, considering both cyst wall preservation and cyst wall resection. The quality assessment of the included studies was carried out using the Methodology Index for Non-Randomized Research criteria. Following this, meta-analyses were conducted, employing odds ratios (ORs) for dichotomous outcomes and calculating mean differences (MDs) for continuous outcomes.

Four articles included a collective of 214 knees. Each of these studies presented level 3 evidence. The comparison between the cyst wall preservation group and the cyst wall resection group revealed similar clinical outcomes based on the Rauschning and Lindgren grade (grade 0 [OR = 0.66, 95% CI: 0.37–1.19, p = 0.17]; grade I [OR = 1.33, 95% CI: 0.66–2.67, p = 0.43]; grade II [OR = 1.39, 95% CI: 0.46–4.14, p = 0.56]; grade III [OR = 3.46, 95% CI: 0.13–89.95, p = 0.46]) and Lysholm score (MD = 0.83, 95% CI: -0.65–2.32, p = 0.27). However, MRI results indicated a significant improvement in the cyst wall resection group (cyst disappearance [OR = 0.50, 95% CI: 0.28–0.90, p = 0.02]; cyst shrinkage or decrease in size [OR = 1.41, 95% CI: 0.78–2.55, p = 0.26]; cyst persistence or recurrence [OR = 7.63, 95% CI: 1.29–45.08, p = 0.02]). Nevertheless, the operative time for cyst resection was significantly longer compared to cyst preservation (MD = -14.90, 95% CI: -21.96 – -7.84, p < 0.0001), and the cyst wall resection group experienced significantly higher complications than the cyst wall preservation group (OR = 0.24, 95% CI: 0.06 to 1.02, p = 0.05).

During arthroscopic popliteal cyst decompression, cyst wall resection led to longer operative times and higher complication rates but lower recurrence rates and better MRI outcomes. The functional outcomes after surgery were found to be similar.