Introduction
Total knee replacement (TKR) is a common orthopedic procedure performed to relieve pain and restore function of the knee joint damaged by osteoarthritis or other joint injuries. This surgical intervention involves replacing the entire surface of the knee joint with prosthetic components to create a new artificial joint. In this case review essay, I will present the case of a 67-year-old female patient named Ms. Jane Doe who underwent a unilateral primary total knee arthroplasty for treatment of osteoarthritis. The case will be analyzed by discussing pertinent clinical and diagnostic details, surgical procedure details, postoperative care and rehabilitation, as well as short-term and long-term outcomes.
Clinical Presentation and Diagnosis
Ms. Doe presented to her orthopedic surgeon with a several month history of progressively worse right knee pain localized to the medial joint line and patellofemoral region. Her pain was worse with activity such as walking or stair usage and improved with rest. On physical examination, the surgeon noted pain on palpation of the medial and lateral joint lines, crepitus with range of motion, limited flexion to 110 degrees, and tenderness of the patella on compression. Standard knee X-rays revealed significant tricompartmental osteoarthritis with medial joint space narrowing, bone spurs (osteophytes), and sclerosis. MRI was not indicated in this case given the clinical and radiographic findings were consistent with advanced osteoarthritis. Based on the history, physical exam findings, and imaging studies, the diagnosis of advanced tricompartmental osteoarthrosis (osteoarthritis) of the right knee was made. Conservative treatment with pain medication and bracing had failed to provide adequate relief, so the patient elected to proceed with surgery.
Surgical Procedure
Ms. Doe underwent a unilateral right total knee arthroplasty done under general anesthesia and antibiotic prophylaxis in a sterile operating room setting. A midline skin incision was made over the knee joint and the patella was everted to expose the articular surfaces. Using an extramedullary alignment guide, femoral and tibial resection guides were placed to establish correct leg alignment and femoral-tibial sizing. An oscillating bone saw was used to remove approximately 8-10mm of bone from the distal femur and proximal tibia in a sequential fashion to create flat surfaces for implantation of prosthetic components. The patellar was replaced and prepared for tracking over the new femoral component. Cemented prostheses were selected given the patient’s bone quality and age. Sizing trials were used to determine correct femoral, tibial, and patellar component sizes. The femoral component with a built-in articulating surface was secured to the distal femur using bone cement. The tibial baseplate with a polyethylene insert was cemented into place on the proximal tibial cut surface. The patellar was checked for appropriate tracking and tightness. Hemostasis was achieved and layered soft tissue closure was performed in anatomic fashion over a drain.
Postoperative Care and Rehabilitation
Early postoperative care consisted of leg elevation, cryotherapy, compression stockings, medication for pain and thrombosis prophylaxis. Ms. Doe began physical therapy on postoperative day one for range of motion and muscle strengthening exercises. She progressed to use of a walker initially for ambulation and advanced to a cane over the next few weeks. Strict weight-bearing restrictions were applied during the six week postoperative period. At subsequent clinic visits, radiographs showed maintained prosthetic position and alignment. Range of motion improved quickly from 0-90 degrees initially to 0-115 degrees by six weeks postop. The patient’s leg swelling and pain diminished significantly. Therapy focused on advancing strength, gait, and functional activities. By three months postop, she was able to walk without an assistive device, climb stairs normally, and perform daily living activities independently.
Outcomes
At one year follow up, Ms. Doe reported being very pleased with the outcome of her total knee replacement. She had virtually no pain in the right knee and full active and passive range of motion from 0-125 degrees. Her leg strength returned to normal levels and she was again able to engage in leisure activities such as golfing, gardening, and hiking without limitations. Repeat radiographs showed stable prosthetic components in anatomic alignment without evidence of loosening or osteolysis. She had resumed her normal daily and recreational activities without difficulty. Her Knee Society clinical rating score increased from a preoperative 40 to a postoperative 95, indicating an excellent functional result. Overall, the TKR achieved its goal of relieving knee pain and fully restoring function in this patient with advanced osteoarthritis. She was extremely satisfied that surgery provided high quality improvement in her quality of life. Barring any future complications, the cemented prosthesis was expected to function well for 10-15 years.
Discussion and Conclusion
This case review has described the clinical presentation, diagnosis, surgical management and both short-term and long-term outcomes of a 67-year-old female who underwent unilateral primary total knee arthroplasty for severe osteoarthritis. Key points were discussed such as the preoperative clinical and imaging findings consistent with advanced tricompartmental arthrosis, the cemented prosthetic technique utilized in surgery, early postoperative rehabilitation protocols emphasizing range of motion and strengthening, and excellent functional recovery by one year postop with pain relief, activity restoration, and prosthetic stability on radiographs. Total knee replacement is one of the most commonly performed and successful orthopedic procedures worldwide for end-stage arthritis of the knee joint. When the surgery is appropriately indicated and performed by an experienced surgeon, most patients can expect significant pain relief and functional improvement as was seen in this case. Total knee arthroplasty provides highly effective treatment for osteoarthritis and enables individuals to return to a high quality of life through restoration of mobility and independence in daily activities.
Andrew Stroud