Outcomes of Early Versus Delayed Manipulation Under Anesthesia for Stiffness Following Total Knee Arthroplasty: A Systematic Review and Meta-Analysis.

BACKGROUND

Stiffness following total knee arthroplasty (TKA) is often treated with manipulation under anesthesia (MUA). However, there is debate regarding the timing of MUA, with many recommending against MUA beyond 3 months after TKA. Therefore, the purpose of this systematic review was to evaluate the functional and clinical outcomes of early versus delayed MUA for stiffness following TKA.

METHODS

A search following Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines was performed in the PubMed, Embase, Scopus, and Cochrane databases in November 2023. Data regarding study characteristics, demographics, knee flexion and extension, patient-reported outcomes, complications, and revisions were collected. A quality assessment was performed using the Methodological Index for Non-randomized Studies. Included were 14 studies analyzing 13,445 knees, 72.1% of which underwent early MUA and 27.8% of which underwent delayed MUA. Of the 14 studies, 10 defined early MUA as being performed within 3 months of the index TKA.

RESULTS

Pre-MUA and post-MUA knee flexion for the early/delayed groups was 71.3°/77.9° and 103.0°/96.1°, respectively. Upon meta-analysis, pre-MUA knee flexion was significantly higher in the delayed group (P = .003), whereas post-MUA flexion was similar in both groups (P = .36). The mean gain in knee flexion for the early and delayed groups was 32.0°/19.2°. The surgical complication and revision TKA rates for the early and delayed groups were 4.9%/10.3% and 5%/9%, respectively. A meta-analysis found the risk of surgical or medical complications and revision TKA to be significantly higher in the delayed MUA group (P < .00001 and = .002, respectively).

CONCLUSIONS

Although post-MUA knee flexion was similar in patients undergoing early and delayed MUA following TKA, the mean gain in flexion for early patients was nearly double that of delayed patients. Delayed patients also had significantly higher risks of surgical or medical complications and revision TKA following MUA.