Manipulation and Injection after Total Knee Arthroplasty: Incidence and Outcomes.

Following total knee arthroplasty (TKA), stiffness can lead to poor outcomes. Manipulation under anesthesia (MUA) is sometimes combined with corticosteroid injection (CSI). This study sought to describe the incidence of CSI with MUA after TKA, as well as the odds of prosthetic joint infection (PJI). A database was queried to identify 754,421 primary TKA patients. The incidences of MUA, injection, revision, and PJI were investigated, along with patient characteristics before and after matching. Overall, 22,015 (2.9%) underwent MUA alone, and 3,272 (14.9% of MUA procedures) underwent MUA with injection. The odds of all-cause revision (1.0, p = 1.0) and revision with PJI (1.1, p = 0.83) were not significantly higher following injection, even after matching (0.9, p = 0.29 and 0.9, p = 0.77, respectively). Overall, the incidence of MUA following TKA within 90 days of index surgery was low and one in seven underwent injection. Injection during MUA did not increase odds of PJI. (Journal of Surgical Orthopaedic Advances 34(3):134-137, 2025).