title: Navigated shorter incision or smaller implant in knee arthritis?
abstract: Minimally invasive approaches for unicompartmental knee arthroplasty are well-accepted for treating knee arthritis because of the smaller implant size, shorter operative time, and tissue-sparing nature of the procedure. With the introduction of computer alignment systems, a well-aligned and balanced total knee arthroplasty (TKA) can be achieved even with smaller surgical exposures. We hypothesized a unicompartmental knee arthroplasty would provide better midterm outcomes than a computer-assisted minimally invasive TKA in patients with isolated medial compartment knee arthritis. We matched (preoperative arthritis severity, age, gender, and preoperative range of motion) 64 knees that had a medial unicompartmental knee arthroplasty or a mini-incision computer-assisted TKA. All patients had a varus deformity no greater than 8 degrees and a body mass index lower than 30 kg/m. Patients were followed a minimum of 48 months. In the mini-incision computer-assisted TKA group, all the implants were positioned within 4 degrees of ideal alignment. The surgical time and hospital stay were longer in the computer-assisted TKA group. A unicompartmental knee arthroplasty was estimated to cost at least 3100 euros (approximately US $4100) less. The clinical assessment showed higher functional and Italian Orthopaedic UKA Users Group scores for the unicompartmental knee arthroplasty group.
authors.affiliation: First Orthopaedic Department, Centro Traumatologico ed Ortopedico (CTO)-ICP, Milan, Italy.
authors.forename: N
authors.initials: N
authors.lastname: Confalonieri
authors.forename: A
authors.initials: A
authors.lastname: Manzotti
authors.forename: C
authors.initials: C
authors.lastname: Pullen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000191:economics / Q000295:instrumentation* / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D005102:Health Expenditures / Q000706:statistics & numerical data; D006801:Humans; D007720:Knee Prosthesis; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures; D020370:Osteoarthritis, Knee / Q000503:physiopathology / Q000601:surgery*; D011183:Postoperative Complications / Q000209:etiology / Q000517:prevention & control; D011474:Prosthesis Design; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome