Systematic analysis of painful total knee prosthesis, a diagnostic algorithm.

Remaining pain after total knee arthroplasty (TKA) is a common observation in about 20% of postoperative patients; where in about 60% of these knees require early revision surgery within five years. Obvious causes of this pain could be identified simply with clinical examinations and standard radiographs. However, unexplained painful TKA still remains a challenge for the surgeon. The management should include a multidisciplinary approach to the patient`s pain as well as addressing the underlying etiology. There are a number of extrinsic (tendinopathy, hip, ankle, spine, CRPS and so on) and intrinsic (infection, instability, malalignment, wear and so on) causes of painful knee replacement. On average, diagnosis takes more than 12 months and patients become very dissatisfied and some of them even acquire psychological problems. Hence, a systematic diagnostic algorithm might be helpful. This review article aims to act as a guide to the evaluation of patients with painful TKA described in 10 different steps. Furthermore, the preliminary results of a series of 100 consecutive cases will be discussed. Revision surgery was performed only in those cases with clear failure mechanism.