MANIPULATION UNDER ANAESTHETIC FOLLOWING TOTAL KNEE ARTHROPLASTY - PREDICTIONS AND OUTCOMES

Purpose To review the outcomes of patients undergoing manipulation under anaesthetic (MUA) after primary total knee arthroplasty (TKA) and predict those that may require such a procedure. Methods We prospectively analysed all patients who required MUA post TKA performed by 2 surgeons using the same prosthesis from 2003 to 2008 and compared them to a control group of primary TKA matched for age, gender and surgeon. All patients in both groups had pre- and post-operative measurements of range of movement. In addition risk factors were identified including warfarin and statin use, diabetes and body mass index. Results Seventy-two patients required an MUA out of 1313 TKAs (5.5%) and were compared to a control group of 50 patients. The mean arc of motion preoperatively was 89.0° (MUA group) vs 92.2° (control) (p=0.47), at discharge 71.0° vs 76.8° (p 12 months (7 patients) 81° to 89° (p=0.32). Mean increase of extension was 3.7° on table and 3.6° at 12 months. Mean flexion increase was 40.5° on table and 15.7° at 12 months. The relative risk factor for requiring an MUA was 6.97 warfarin (p Conclusions MUA for patients with stiffness after primary TKA improves their range of motion if done within 12 months, however only 40% flexion improvement is maintained. Patients who will require an MUA have a reduced motion at discharge. Patients on warfarin therapy are more likely to get stiffness.