JOA - 2026-03-20 - Journal Article
Failure Incidence and Predictors Following Manipulation Under Anesthesia for the Stiff Total Knee Arthroplasty.
Hurn MT, Balbuena JR, Heironimus EE, Henningsen JD, Smith LS, Tillett ED, Malkani AL
Topics
Key Takeaway
MUA for post-TKA stiffness fails in 17.2% of cases, with ROM <96.4° at two weeks post-MUA, younger age, and cruciate-retaining implants independently predicting need for additional surgical intervention.
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Summary
This study evaluated predictors of MUA failure in 227 knees treated for post-TKA arthrofibrosis, comparing 39 patients requiring additional intervention to 174 who did not. ROM at two weeks post-MUA was significantly lower in the failure group (96.4° vs. 107.4°, P<0.001), and multivariate analysis identified younger age, cruciate-retaining implants, and two-week ROM as independent failure predictors. At final follow-up, failed MUA patients had significantly worse KSS Knee (79.1 vs. 89.0), KOOS-JR (65.0 vs. 80.2), FJS-12 (39.1 vs. 62.0), and Likert satisfaction (3.5 vs. 4.5).
Key Limitation
Retrospective design cannot establish whether CR implant design caused failure or was a surrogate for other surgical or patient factors driving both implant choice and stiffness.
Original Abstract
BACKGROUND
Manipulation under anesthesia (MUA) is a common treatment for stiffness following total knee arthroplasty (TKA). The purpose of this study was to evaluate the outcomes following MUA and identify risk factors for additional surgical intervention.
METHODS
This study analyzed 227 knees that underwent MUA following primary TKA with 1-year follow-up. The 39 patients (17.2%) who required additional intervention were compared to 174 patients who underwent MUA without further interventions. There were no differences in body mass index, American Society of Anesthesiologists class, and prior knee surgeries. The mean follow-up was 38.5 months (range, 12 to 119.5) in the failure group and 39.2 (range, 12 to 124.2) in the control cohort.
RESULTS
Of the 39 patients requiring additional procedures, 29 (74%) underwent arthroscopic lysis of adhesions and 15 (38%) revision TKA. Range of motion (ROM) two weeks following MUA was lower in patients who had additional interventions (96.4 versus 107.4°, P < 0.001), as was ROM at one year (103.1 versus 112.9°, P < 0.001). Multivariate analyses found age, cruciate-retaining implants, and ROM two weeks after MUA as independently associated with failure. There were no differences in preoperative Knee Society Score (KSS) Function, KSS Knee, and Knee Injury and Osteoarthritis Outcome Score for Joint Replacement scores. At the latest follow-up, patients who failed MUA had inferior KSS Knee (79.1 versus 89.0, P = 0.003), Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (65.0 versus 80.2, P < 0.01), Forgotten Joint Score-12 (39.1 versus 62.0, P < 0.01), and Likert satisfaction scores (3.5 versus 4.5, P < 0.01).
CONCLUSIONS
This study demonstrated a 17.2% reoperation incidence following MUA. Decreased ROM at two weeks, age, and cruciate-retaining implants were associated with additional intervention. These findings underscore the importance of early ROM recovery following MUA and the need for better understanding the biologic aspects of arthrofibrosis.