Total hip arthroplasty after a previous pelvic osteotomy: A systematic review and meta-analysis.

BACKGROUND: There are several reports regarding total hip arthroplasty (THA) after a previous pelvic osteotomy (PO). However, to our knowledge, until now there has been no formal systematic review and meta-analysis published to summarize the clinical results of THA after a previous PO. Therefore, we conducted a systematic review and meta-analysis of results of THA after a previous PO. We focus on these questions as follows: does a previous PO affect the results of subsequent THA, such as clinical outcomes, operative time, operative blood loss, and radiological parameters.

METHODS: Using PubMed, Web of Science, and Cochrane Library, we searched for relevant original papers. The pooling of data was performed using RevMan software (version 5.3, Cochrane Collaboration, Oxford, UK). A p-value<0.05 was judged as significant. Standardized mean differences (SMD) were calculated for continuous data with a 95% confidence interval (CI) was reported. Statistical heterogeneity was assessed based on I2 using standard χ2 test. When I2 >50%, significant heterogeneity was assumed and a random-effects model was applied for the meta-analysis. A fixed-effects model was applied in the absence of significant heterogeneity.

RESULTS: Eleven studies were included in this meta-analysis. The pooled results indicated that there was no significant difference in postoperative Merle D'Aubigne-Postel score (I2 =0%, SMD=-0.15, 95% CI: -0.36 to 0.06, p=0.17), postoperative Harris hip score (I2 =60%, SMD=-0.23, 95% CI: -0.50 to 0.05, p=0.10), operative time (I2 =86%, SMD=0.37, 95% CI: -0.09 to 0.82, p=0.11), operative blood loss (I2 =82%, SMD=0.23, 95% CI: -0.17 to 0.63, p=0.25), and cup abduction angle (I2 =43%, SMD=-0.08, 95% CI: -0.25 to 0.09, p=0.38) between THA with and without a previous PO. However, cup anteversion angle of THA with a previous PO was significantly smaller than that of without a previous PO (I2 =77%, SMD=-0.63, 95% CI: -1.13 to -0.13, p=0.01).

CONCLUSION: Systematic review and meta-analysis of results of THA after a previous PO was performed. A previous PO did not affect the results of subsequent THA, except for cup anteversion. Because of the low quality evidence currently available, high-quality randomized controlled trials are required.

LEVEL OF EVIDENCE: Level III, meta-analysis of case-control studies.