Unicompartmental or Total Knee Arthroplasty?

Abstract

There are few direct comparative studies evaluating results after unicompartmental knee arthroplasty and total knee arthroplasty. We determined the active range of motion, Knee Society score, and 5-year survivorship rate after 54 consecutive unilateral unicompartmental knee arthroplasties compared with a matched group of 54 unilateral total knee arthroplasties. The two groups of patients were matched for age, gender, body mass index, preoperative active range of movement, and preoperative Knee Society scores. All patients had osteoarthritis of the knee. Patients were assessed prospectively at 6, 18, 36, and 60 months postoperatively, and the mean followup was 59 months in both groups. The mean postoperative active range of motion was greater after unicompartmental knee arthroplasty, but there were no differences in the overall Knee Society knee and function scores. The 5-year survivorship rate based on revision for any reason was 88% for unicompartmental knee arthroplasty and 100% for total knee arthroplasty. The worst case 5-year survivorship rate, assuming all patients lost to followup had revision surgery, was 85% for unicompartmental knee arthroplasty and 98% for total knee arthroplasty. Total knee arthroplasty was a more reliable procedure. Midterm clinical outcomes were similar for both procedures, but the complication rate may be greater for unicompartmental knee arthroplasty.

Unicompartmental Versus Total Knee Arthroplasty Database Analysis: Is There a Winner?

“…Proposed advantages of UKA over TKA include both technical factors (less invasive surgery, preservation of bone stock, comparative ease of revision) [5,32,37,41,56] and improved clinical outcomes (superior knee kinematics, less blood loss, faster recovery, shorter inpatient stay) [4, 20-22, 25-27, 50, 62]. Clinical outcome scores have previously focused on absolute values at preoperative and postoperative review.…”

“…TKA, including minimal access surgery, preservation of bone stock, and ease of revision [5,32,37,41,56], as well as superior knee ROM and kinematics, less blood loss, faster recovery, and a decreased hospital admission [4, 20-22, 25-27, 50, 62]. Satisfaction after either TKA or UKA is similar [54].…”

Does Interlimb Knee Symmetry Exist After Unicompartmental Knee Arthroplasty?

“…Use of unicompartmental knee arthroplasty (UKA) has increased considerably in recent decades as a result of improved implant technology and surgical techniques [3,28]. It has been suggested that UKA should result in a more normal restoration of knee function compared with TKA because the procedure requires less soft tissue dissection and both cruciate ligaments are preserved [7,14].…”

“…However, studies on survival rates and clinical measures (eg, Knee Society scores) of UKA demonstrate mixed results [3,12,15,28,30], and some evidence of early failure rates has been reported [21]. Therefore, some surgeons are reluctant to use this procedure as a result of conflicting evidence of effectiveness [3,12,15,28,30].…”

An Analysis of Risk Factors for Short-Term Complication Rates and Increased Length of Stay Following Unicompartmental Knee Arthroplasty

“…In the setting of isolated unicompartmental knee osteoarthritis, many surgeons elect to perform UKA citing its potential benefits, including decreased operative time, smaller incision, less aggressive bony resection, preservation of cruciate ligaments, improved range of motion, shorter hospital length of stay, decreased morbidity and mortality, and its preserved knee kinematics [2,15,22,23,26,36]. Despite these benefits, there appears to be conflicting reports in the literature with regards to the long-term survival of UKA implants; with registry data demonstrating increased rates of revision compared to TKA [20,21,28], while case series demonstrate equivalent outcomes [5,10,16,17,25,27,30,32,34].…”