Automated impaction in uncemented total hip arthroplasty : a systematic review and meta-analysis

Intraoperative periprosthetic femoral fractures (IPFs) are a serious complication of total hip arthroplasty (THA), typically attributed to surgical technique. Manual impaction provides tactile feedback but varies with surgeon fatigue and experience. Automated impaction systems offer consistent energy delivery, potentially improving safety and efficiency. This study aimed, through a systematic review and meta-analysis, to compare the risk of IPF and operating times between automated and manual impaction during primary uncemented THA.

We performed a systematic review and random-effects meta-analysis of primary uncemented THA studies comparing automated and manual impaction techniques. Outcomes included IPFs and operating time. Pooled odds ratios (ORs) were calculated for IPF risk, and differences in mean operating time between techniques were analyzed using mean differences with 95% CIs.

Comparative data were available from five studies (n = 2,607 THAs). Meta-analysis included three studies (n = 2,377), with 1,408 hips in the automated group (14 IPFs) and 969 hips in the manual group (three IPFs). There was no significant difference in IPF risk between techniques (pooled OR 1.29; 95% CI 0.52 to 3.21; p = 0.59). Operating time was reported in three studies. The pooled mean difference suggested a shorter operating time with automated impaction (-1.34 minutes; 95% CI -15.60 to 12.92; p = 0.72).

Automated impaction was not associated with a lower risk of IPF or operating time compared with manual techniques in primary uncemented THA. Fracture risk and efficiency may instead depend on femoral component-femur compatibility and implant sizing. Further randomized studies incorporating diverse femoral component designs and automated impaction systems, alongside formal economic evaluation, are required.