What Percentage of Patients is a Candidate for Unicompartmental Knee Replacement at a Chinese Arthroplasty Center?

Abstract

Background:Data on indication of Unicompartmental Knee Arthroplasty (UKA) in the Asian population are currently not available. The current paper evaluates patients undergoing knee replacement at a Chinese Orthopaedic Specialty Hospital to report the percentage of patients who meet radiographic and clinical indication criteria for UKA.Methods:Over a one-year period 463 consecutive patients (515 knees) underwent primary knee replacement surgery. Clinical data were recorded and preoperative radiographs were assessed. Patients were classified as suitable candidates for UKA based on the degree of deformity, preoperative ROM and radiographic appearance of osteoarthritis. The different indication criteria for body weight and extend of patellofemoral osteoarthritis as reported by Kozinn and Scott as well as the Oxford Group were applied.Results:160 knees (31%) were excluded because of inflammatory and posttraumatic arthritis. 55 knees had to be excluded because of incomplete radiographs. Of the remaining 300 knees with osteoarthritis, 241 knees were excluded because of extend of deformity (n=156), decreased range of motion (n=119), advanced patellofemoral arthritis with bone loss (n=11) and AP instability (n=1). Of the remaining 63 knees, 54 knees (18%) met the modified Oxford criteria for mobile UKA and only 25 knees (8%) met the Scott and Kozinn criteria for fixed UKA.Conclusion:The current paper suggests that in comparison to Caucasian population, only a smaller percentage of patients at a Chinese Orthopaedic Specialty Hospital meet the indication criteria for UKA. Therefore, it might make sense to concentrate UKA surgeries in high volume centers.

Most unicompartmental knee replacement revisions could be avoided: a radiographic evaluation of revised Oxford knees in the National Joint Registry

“…In only 3% of cases was the disease more severe than recommended (2% with lateral joint space narrowing and 1% with radiographic evidence of a non-functional ACL). The recommended indications are satisfied in up to 50% of knee replacements [ 11 , 13 , 38 ], yet the NJR shows that UKR is used in only 10% of cases [ 28 ]. This study, therefore, suggests that many surgeons are implanting UKR in patients with early disease, without bone-on-bone arthritis, and are not adhering to the recommended indications.…”

“…Better patient reported outcomes can be obtained with UKR [ 20 ], and patients recover quicker and can be discharged earlier so there are appreciable cost savings [ 3 ]. Up to 50% of knees requiring replacement satisfy the recommended indications for UKR [ 11 , 13 , 38 ], yet less than 10% are treated with UKR. If the causes for the high revision rates in registers could be identified and addressed then more patients could be treated with UKR with benefits to patients and the health service.…”