Abstract
Stiffness remains one of the most common, and challenging post-operative complications after TKA. The exact definition of stiffness varies, and patient expectations of post-operative motion vary as well. Pre-operative motion and diagnosis (such as post-traumatic arthritis) can influence post-operative motion, and careful patient counseling about expectations is important. Post-operative stiffness should be evaluated by ruling out infection, evaluating rehabilitation efforts, and careful physical and radiographic examination. Manipulation under anesthesia (MUA) in selected cases can be helpful. The author generally prefers to perform MUA between the 6- and 8-week mark post-operatively. Careful technique is required to minimised the risk of fracture or soft tissue injury. For more chronic stiffness, revision may be indicated, especially if an etiology is identified pre-operatively (for example, an excessively thick patellar resurfacing, an oversized femoral component, gross malrotation, etc.). CT scanning can be helpful for pre-operative evaluation and planning. During revision, thorough synovectomy and release of contractures and ligamentous balancing is performed as required. Careful attention to gap balancing, component rotation, and sizing is critical. Patients should be counseled that the results of revision for stiffness are mixed and somewhat unpredictable unless a clear etiology was found intra-operatively (for example, a grossly oversized femoral component). More frequent post-operative office visits may be helpful to guide rehabilitation progress in these challenging cases.
