Incidence and effectiveness of manipulation under anaesthesia for stiffness following primary total knee arthroplasty

Background: There are various modalities of correction of stiffness following total knee arthro-plasty. Manipulation under anaesthesia (MUA) is generally indicated for people who fail to achieve their pre operative range of motion at 12 weeks. The purpose of this study was to determine: (1) the effect of MUA on Flexion arc (2) the influence of timing of MUA from index procedure and of diabetes mellitus on final flexion achieved. Methods: We retrospectively evaluated patients who underwent manipulation following total knee arthroplasty at our institution between January 2016 to December 2018. For the purpose of analysis, we have divided the patients into two groups. Those who underwent manipulation within 12 weeks and later than 12 weeks. We have also compared the effect of MUA between diabetic and non-diabetic patients. All were operated with posterior stabilised (PS) prosthesis by a single senior arthroplasty surgeon. The final flexion achieved during their last clinical follow-up were recorded and compared with the pre MUA flexion. Results: The incidence of MUA after TKA at our institute during this period is about 1.14 %. There was a significant statistical difference between the pre and post manipulation flexion, with p value <0.01. There was no significant statistical difference between those who were manipulated before 12 weeks and after 12 weeks in improving the Flexion of the operated knees. We have found that both the diabetic and non diabetic group had comparable flexion after the manipulation in our study. Conclusion: Manipulation after anaesthesia is a safe first intervention to improve post operative stiffness and gain additional range of motion following TKA in patients who develop stiffness. It can be done even after 12 weeks of surgery with reasonably good gain in range of motion.