Total Knee Replacement
Related narratives: Total Knee Replacement
Arthritis and related conditions are leading causes of disability in our nation. The knee is one of the most common areas involved in the degenerative process and almost 200,000 Americans undergo Total Knee Replacement (TKR) yearly. The techniques used have been developed over many years and technological advances are continually emerging.
Patients generally present with a combination of severe, debilitating knee pain, loss of motion, instability, painful swelling, inability to ambulate and difficulty with activities of daily living. Physical findings may include gait disturbances, flexion contractures, decreased range of motion, painful effusions, painful osteophytes and joint instability. X-rays may reveal decreased joint space, deformity, sclerosis, osteophyte formation and cyst formation with varying degrees of bone loss. Hip arthritis and spinal conditions may cause knee and lower leg pain so these conditions must be carefully excluded.
Initial treatments involve activity modification, physical therapy, aerobic conditioning and weight loss. Patients may benefit from shoe modifications and the use of assistive devices such as a cane or a walker.
Medical intervention is targeted at decreasing swelling and pain and is initially managed with over the counter analgesics and anti-inflammatory agents.
When conservative non-operative treatments fail and patients develop end stage disabling arthritis, surgical intervention is considered. Patients must be screened and selected carefully. Most patients have multiple medical issues and preoperative risk assessment including medical and cardiac evaluation and clearance is essential. Occasionally patients will require invasive cardiac procedures and cardiac bypass surgery prior to considering total joint reconstruction. Patients must be willing and capable to comply with a progressive organized physical therapy protocol in order to maximize post-operative outcome.
The ultimate goals of TKR are pain relief and return to a higher level of functioning. Paramount to the technical success of the operation are reestablishing the joint line, improvement of the mechanical pull of the quadriceps mechanism and restoration of the mechanical alignment of the lower extremity.
A tremendous amount of research is dedicated to developing new techniques, refining and developing implant materials and providing the best combination of form and function, which will allow the patient the greatest longevity. Current techniques and materials are expected to provide excellent patient satisfaction and total knee replacements that will last fifteen (15) years or more.
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