Total Knee Arthroplasty in Patients With Prior Ipsilateral Hip Fusion: A Surgical Technique

Background: In patients with severe osteoarthritis of the knee with prior ipsilateral hip fusion who require total knee arthroplasty (TKA), a controversial issue is whether to first convert the hip fusion to a total hip arthroplasty (THA) or to perform TKA without reconstruction of the hip. Also, immobility of the ipsilateral, fused hip adds significant technical challenge because the usual positioning of the leg requires modification in order to gain access needed for the TKA. Technique: In such cases, we position the patient with the knee suspended, similar to how we perform knee arthroscopy. In our experience, the ipsilateral knee has significant deformity and is best addressed with a constrained, hinged TKA. Results: In 3 patients with severe knee osteoarthritis with prior ipsilateral hip fusion—a 72-year-old man and a 79-year-old woman with hip arthrodesis due to posttraumatic arthritis and an 81-year-old woman with hip arthrodesis due to congenital dislocation of the hip—rotating-hinge knee prostheses were implanted due to severe knee instability. All 3 patients had satisfactory results, without complications, after follow-up of 1 to 5 years. Conclusions: We obtained satisfactory results in the short and medium term without previously converting the hip arthrodesis to THA by positioning patients with the knee suspended, in a way similar to when knee arthroscopy is performed, and implanting rotating hinge TKAs due to severe preoperative knee instability.

Review of complications, functional outcome, and long-term survival following conversion of hip fusion to total hip arthroplasty

Aims Improvements in functional results and long-term survival are variable following conversion of hip fusion to total hip arthroplasty (THA) and complications are high. The aim of the study was to analyze the clinical and functional results in patients who underwent conversion of hip fusion to THA using a consistent technique and uncemented implants. Methods A total of 39 hip fusion conversions to THA were undertaken in 38 patients by a single surgeon employing a consistent surgical technique and uncemented implants. Parameters assessed included Harris Hip Score (HHS) for function, range of motion (ROM), leg length discrepancy (LLD), satisfaction, and use of walking aid. Radiographs were reviewed for loosening, subsidence, and heterotopic ossification (HO). Postoperative complications and implant survival were assessed. Results At mean 12.2 years (2 to 24) follow-up, HHS improved from mean 34.2 (20.8 to 60.5) to 75 (53.6 to 94.0; p < 0.001). Mean postoperative ROM was flexion 77° (50° to 95°), abduction 30° (10° to 40°), adduction 20° (5° to 25°), internal rotation 18° (2° to 30°), and external rotation 17° (5° to 30°). LLD improved from mean -3.36 cm (0 to 8) to postoperative mean -1.14 cm (0 to 4; p < 0.001). Postoperatively, 26 patients (68.4%) required the use of a walking aid. Complications included one (2.5%) dislocation, two (5.1%) partial sciatic nerve injuries, one (2.5%) deep periprosthetic joint infection, two instances of (5.1%) acetabular component aseptic loosening, two (5.1%) periprosthetic fractures, and ten instances of HO (40%), of which three (7.7%) were functionally limiting and required excision. Kaplan-Meier Survival was 97.1% (95% confidence interval (CI) 91.4% to 100%) at ten years and 88.2% (95% CI 70.96 to 100) at 15 years with implant revision for aseptic loosening as endpoint and 81.7% (95% CI 70.9% to 98.0%) at ten years and 74.2% (95% CI 55.6 to 92.8) at 15 years follow-up with implant revision for all cause failure as endpoint. Conclusion The use of an optimal and consistent surgical technique and cementless implants can result in significant functional improvement, low complication rates, long-term implant survival, and high patient satisfaction following conversion of hip fusion to THA. The possibility of requiring a walking aid should be discussed with the patient before surgery. Cite this article: Bone Joint J 2021;103-B(7 Supple B):129–134.

Hip Fusion Takedown with Subsequent Hip and Knee Arthroplasty. Case Study

There is no uniform standard of treatment for patients with hip fusion and accompanying symptomatic osteoarthritis of the ipsilateral knee. Fusion takedown is associated with an increased risk of complications, and often the results are not satisfactory for patients. Therefore, each case should be considered individually. We present a case report regarding a 70-year-old patient with hip fusion as a result of tuberculosis at a young age who underwent hip fusion takedown with total hip arthroplasty followed by total knee arthroplasty as a second step. The 70-year-old patient with end-stage renal failure and hip fusion as a complication of tuberculosis in adolescence complained of increasing pain in the left knee. After taking into account his comorbidities and discussing with the patient possible treatment options and their limitations, he was qualified for 2-step surgery involving hip replacement and total knee replacement spaced 5 months apart. At the last follow-up visit the patient did not report any pain, with a hip joint mobility of 110° flexion and -10° extension and internal and external rotation of 35° each. The range of knee flexion was 110°. On a VAS scale, the patient’s quality of life was rated 85/100 vs. 30/100 preoperatively. In patients with hip fusion, satisfactory results can be achieved with 2-stage hip and knee replacement, even despite significant co-morbidities. However, this requires careful intraoperative planning and management of patient expectations.