Abstract
Stiffness after a TKA might be said to be present when reasonable functions of daily living cannot be performed or can only be performed with difficulty or pain. This will certainly be true if flexion is less than 75 degrees and/or there is a 15-degree lack of full extension. The purpose of this presentation is to discuss the causes of a stiff TKA, consider the aspects of surgical technique that are associated with the occurrence of stiffness, present post-surgical management that impacts on the development of stiffness and summarise the results of the surgical treatment of a stiff TKA.
Pre-operative stiffness is strongly correlated with post-operative limitation of motion. Therefore, pre-surgical measures to optimise motion should be carried out. These include appropriate physical therapy, adequate pain management and a discussion with the patient of the issues likely to affect post-operative range of motion. It is particularly important to discuss with the patient appropriate expectations with regard to the likely range of motion that will be achieved following TKA surgery.
There are a number of steps that can be taken during the performance of a TKA that have an impact on range of motion. Osteophytes must be removed. Correctly sized implants must be used to avoid over-stuffing the tibio-femoral and patello-femoral compartments. Mal-positioning implants and the extremity can adversely affect range of motion. Inadequate bone resection will also lead to a reduced range of motion. Improper soft tissue balancing in both flexion and extension may be associated with post-surgical stiffness.
Post-operative management must include adequate pain management as well as appropriate rehabilitation. Close post-surgical surveillance will help identify those patients likely to achieve unsatisfactory range of motion. Manipulation of appropriate patients within the first 6 weeks following surgery is usually associated with a satisfactory final range of motion.
When persistent stiffness occurs, an attempt must be made to identifying possible causes, including component mal-alignment or mal-rotation, component mis-sizing or mis-positioning and inadequate soft tissue balancing. The surgical treatment of a stiff total knee include: 1) arthroscopic debridement and manipulation; 2) arthrotomy with debridement; and 3) single or complete component revision. Although surgical intervention often results in improved range of motion, the results are variable and somewhat limited.
