Predictive Factors for Manipulations Under Anesthesia After Total Knee Arthroplasty: An Analysis of 15,139 Cases

This retrospective cohort study analyzed nearly 1 million total knee replacements from a national database to find out which patients most often need a manipulation under anesthesia (MUA) for postoperative knee stiffness. Among 975,235 TKAs, 15,139 (1.55%) required MUA within 90 days, and younger age, female sex, and Black race were independently associated with higher risk (Black race aOR 1.977, 95% CI 1.876-2.083), while perioperative dexamethasone, daily prednisone, and ARB use were associated with lower risk. Diabetes and statin use were linked to slightly higher risk, while several comorbidities (obesity, depression, alcohol abuse) appeared protective, which the authors themselves suspect may reflect confounding.

AI summary · from the full text · reviewed by Pukhraj Gaheer, Medical Student, Queen's University before publishing

Why it mattersIdentifying who is most likely to stiffen up after TKA, and whether cheap perioperative drugs like dexamethasone or ARBs might lower that risk, could shape preoperative counseling and postoperative anti-inflammatory protocols.

Presenting this at rounds? Start here

• ?The study relies on administrative coding and in-hospital medication data as a proxy for home medication use; how might misclassification of exposures like ARB or statin use bias the observed associations?
• ?Given that a prior multicenter RCT (Abdel et al.) found no benefit of perioperative dexamethasone/celecoxib on ROM after MUA, how should surgeons weigh this large observational association against that negative trial when considering steroid protocols to prevent stiffness?