Influence of Subchondral Cysts on the Outcomes of Surgical Treatment for Osteochondral Lesions of the Talus: A Systematic Review and Meta-analysis

Background: Limited literature is available regarding the effect of subchondral cysts on the surgical outcomes for treatment of osteochondral lesion of the talus (OLT).Purpose: To conduct a systematic review and meta-analysis of studies comparing surgical outcomes between OLTs with and without cysts.Study Design: Systematic review; Level of evidence, 4.Methods: Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, the authors searched PubMed, Embase, Web of Science, and the Cochrane Library for relevant studies published up to January 7, 2023. The 4375 retrieved studies were screened, and 9 articles (level of evidence, 2-4) were included, which comprised 165 patients with OLT and subchondral cysts (cyst group) and 223 without cysts (noncyst group). After data extraction, mean differences in outcome scores (American Orthopaedic Foot and Ankle Society [AOFAS] Ankle Hindfoot Scale, visual analog scale [VAS] score for pain) and adverse events were compared between the groups.Results: Functional scores improved after surgery in both groups, with the cyst group having a significantly higher AOFAS score than the noncyst group (P = .005; I2 = 0%); subgroup analysis revealed that this difference was attributable to the size of the osteochondral lesion and the type of surgical procedure. No significant difference was found between the cyst and noncyst groups in VAS pain scores (P = .77; I2 = 0%) or postoperative adverse events (P = .35; I2 = 0%).Conclusion: The results of this review indicated that patients with subchondral cysts improved with surgical treatment of OLT. A relatively low level of evidence was available to indicate that surgical treatment for small OLTs with subchondral cysts will result in better clinical outcomes compared with OLTs without cysts.