Abstract
Stiffness after knee arthroplasty is an important complication that the orthopaedic surgeon must be prepared to manage. In some cases, patients have a low-pain threshold or unidentifiable etiologic findings with no clinical indicators of septic or aseptic failure, and no radiographic evidence of mechanical complications. Psychosocial issues are important to consider, such as patient motivation and etiologic findings related to a worker's compensation claim. For patients who fail to achieve satisfactory ROM after TKA with no identifiable cause, treatment options may be categorised as non-surgical and surgical interventions. Non-surgical interventions would be physical therapy and pharmaceutical control for pain management. Surgical interventions include non-invasive options such as manipulation under anesthesia, and invasive options such as arthroscopy and mini-arthrotomy. Manipulation under anesthesia is indicated in the TKA that has less than 90° ROM after six weeks, no progression or regression in ROM. A modified technique has evolved for patients with persistent stiffness after standard-technique manipulation. The modified technique uses epidural anesthesia continued for post-operative analgesia, hospital stay of 1–3 days, CPM for 2–3 days, and daily PT. Continuous epidural infusion with local anesthetic is administered to provide complete analgesia, but allows muscle activation to be maintained during the hospital stay. Although open revision is sometimes required, arthroscopic management may be an effective alternative in certain instances, and also is helpful in diagnosis and treatment of other conditions of the knee that include prosthetic loosening and failure, retained cement, loose bodies, and sub-clinical infections. However, the painful TKA without evidence of significant intra-articular pathologic findings does not always respond well to arthroscopic management. Another option is open arthrotomy, done mainly to excise scar tissue. A synovectomy may be done as well. The polyethylene insert may be removed and an examination of the posterior cruciate ligament (PCL) performed. If the PCL is tight, it can be released and the existing components may be retained. Sometimes the polyethylene liner may be exchanged to a lipped insert to maintain stability. Revision surgery represents another option of treatment that can provide improved results whether manipulation or arthroscopic debridement has been done (14). Revision of one or all components combined with arthrolysis continues to have a role in improvement of ROM and outcomes in the stiff TKA.
