title: Lateral unicompartmental knee arthroplasty relieves pain and improves function in posttraumatic osteoarthritis.
abstract: BACKGROUND
  Posttraumatic arthritis secondary to lateral tibial plateau fracture malunion causes pain and limited function for patients. It is sometimes technically challenging to correct malalignment in these patients with advanced arthritis using osteotomies. Lateral unicompartmental knee arthroplasty (UKA) may be an option to treat such patients.
  
  
  OBJECTIVE
  We asked whether UKA for lateral posttraumatic osteoarthritis (1) reliably alleviates pain and improve function, (2) restores lower limb alignment, and (3) is as durable as UKA for primary lateral osteoarthritis.
  
  
  METHODS
  We retrospectively reviewed 13 patients with lateral cemented UKA (mean age at surgery, 50.1 years) treated at two institutions between 1985 and 2007. We obtained Knee Society scores and evaluated radiographs for evidence of implant loosening or progression of arthritis in the medial compartment. Minimum followup was 3 years (mean, 10.2 years; range, 3-22.1 years).
  
  
  RESULTS
  Mean Knee Society knee score improved from 51 points (range, 29-75 points) preoperatively to 88 points (range, 65-100 points) at last followup, suggesting the procedure relieved pain. Mean function score improved from 51 points (range, 10-89 points) preoperatively to 87 points (range, 35-100 points) at last followup. The mean hip-knee-ankle angle was 188° preoperatively (range, 184°-193º) and 185° (range, 183°-188°) at last followup. Prosthesis survivorship was 100% at 5 and 10 years and 80% at 15 years.
  
  
  CONCLUSIONS
  Despite the limited number of indications and technical considerations, our observations suggest lateral UKA is a reasonable option for treating lateral arthritis secondary to malunited fractures.
authors: Service de Chirurgie Orthopédique, Hôpital de la Croix Rousse, Lyon University, 103 Grande Rue de La Croix Rousse, 69004 Lyon, France. sebastien.lustig@chu-lyon.fr
authors: Sebastien
authors: S
authors: Lustig
authors: Sebastien
authors: S
authors: Parratte
authors: Robert A
authors: RA
authors: Magnussen
authors: Jean-Noel
authors: JN
authors: Argenson
authors: Philippe
authors: P
authors: Neyret
mesh_terms: D000368:Aged; D018771:Arthralgia / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D057072:Intra-Articular Fractures / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D007718:Knee Injuries / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D010147:Pain Measurement; D011474:Prosthesis Design; D011859:Radiography; D016059:Range of Motion, Articular / Q000502:physiology*; D020127:Recovery of Function; D018570:Risk Assessment; D012720:Severity of Illness Index; D013978:Tibial Fractures / Q000000981:diagnostic imaging / Q000601:surgery; D016896:Treatment Outcome