title: Total Knee Arthroplasty After Failed Unicompartmental Knee Arthroplasty. Clinical Results, Radiologic Findings, and Technical Tips.
abstract: 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.
  
  
  
  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.
  
  
  
  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.
  
  
  
  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: Department of Trauma and Orthopaedics, Virgen del Rocío University Hospital, Seville, Spain.
authors: Estrella
authors: E
authors: Borrego Paredes
authors: Department of Trauma and Orthopaedics, Virgen del Rocío University Hospital, Seville, Spain.
authors: Pablo
authors: P
authors: Barrena Sánchez
authors: Department of Trauma and Orthopaedics, Virgen del Rocío University Hospital, Seville, Spain.
authors: David
authors: D
authors: Serrano Toledano
authors: Department of Trauma and Orthopaedics, Virgen del Rocío University Hospital, Seville, Spain.
authors: Andrés I
authors: AI
authors: Puente González
authors: Department of Trauma and Orthopaedics, Virgen del Rocío University Hospital, Seville, Spain.
authors: Salvador
authors: S
authors: Fornell Pérez
authors: Department of Trauma and Orthopaedics, Virgen del Rocío University Hospital, Seville, Spain.
authors: Gabriel
authors: G
authors: Domecq Fernández de Bobadilla
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000601:surgery; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D010329:Patella; D011859:Radiography; D012086:Reoperation / Q000379:methods*; D012189:Retrospective Studies; D013977:Tibia / Q000601:surgery; D017211:Treatment Failure
keywords: arthroplasty; knee; revision; total; unicompartmental