BACKGROUND: The loss of anatomic references and bone stock turns unicompartmental knee arthroplasty (UKA) revision surgery difficult, and according to some authors, it is technically as challenging as a total knee arthroplasty (TKA) revision surgery. METHODS: A retrospective review of 559 Oxford medial UKA was performed between 2007 and 2013. Nineteen knees were revised to TKA for reasons other than infection, most commonly for osteoarthritis progression. RESULTS: The most frequent cause of failure in our series was osteoarthritis progression (10 cases, 52.63%). In 15 patients (78.95%), tibial stems were needed, and in 10 (55.5%), metallic blocks for augmentation of tibial plateau were used. Postoperative radiographic studies showed a correct implant alignment, preserving adequate joint line (24.8 mm), and patellar (1.1 mm) height (according to Insall-Salvati). After a mean follow-up of 21 months (range 6-51) mean values of 78.8 (standard deviation [SD] = 16.8) and 62.3 (SD = 19.6) were obtained for the physical and mental scores of the Knee Society Score test. In the SF-36 tests mean values of 45.2 (SD = 7.6) and 53 (SD = 5.2) were obtained for the physical and mental scores respectively. In one case, a varus/valgus instability occurred intraoperatively and it required revision with a prosthesis with higher constriction. No thromboembolic or infectious events were observed during postoperative follow-up. CONCLUSION: Following a standardized technique, UKA revision surgery can be achieved with TKA in almost every case despite bone stock loss and lack of anatomic landmarks.
BACKGROUND: The loss of anatomic references and bone stock turns unicompartmental knee arthroplasty (UKA) revision surgery difficult, and according to some authors, it is technically as challenging as a total knee arthroplasty (TKA) revision surgery. METHODS: A retrospective review of 559 Oxford medial UKA was performed between 2007 and 2013. Nineteen knees were revised to TKA for reasons other than infection, most commonly for osteoarthritis progression. RESULTS: The most frequent cause of failure in our series was osteoarthritis progression (10 cases, 52.63%). In 15 patients (78.95%), tibial stems were needed, and in 10 (55.5%), metallic blocks for augmentation of tibial plateau were used. Postoperative radiographic studies showed a correct implant alignment, preserving adequate joint line (24.8 mm), and patellar (1.1 mm) height (according to Insall-Salvati). After a mean follow-up of 21 months (range 6-51) mean values of 78.8 (standard deviation [SD] = 16.8) and 62.3 (SD = 19.6) were obtained for the physical and mental scores of the Knee Society Score test. In the SF-36 tests mean values of 45.2 (SD = 7.6) and 53 (SD = 5.2) were obtained for the physical and mental scores respectively. In one case, a varus/valgus instability occurred intraoperatively and it required revision with a prosthesis with higher constriction. No thromboembolic or infectious events were observed during postoperative follow-up. CONCLUSION: Following a standardized technique, UKA revision surgery can be achieved with TKA in almost every case despite bone stock loss and lack of anatomic landmarks.
Authors: Martijn G M Schotanus; Elke Thijs; B Boonen; B Kerens; B Jong; Nanne P Kort Journal: Knee Surg Sports Traumatol Arthrosc Date: 2017-08-07 Impact factor: 4.342