Early outcomes of twin-peg mobile-bearing unicompartmental knee arthroplasty compared with primary total knee arthroplasty

Abstract

AimsSince redesign of the Oxford phase III mobile-bearing unicompartmental knee arthroplasty (UKA) femoral component to a twin-peg design, there has not been a direct comparison to total knee arthroplasty (TKA). Thus, we explored differences between the two cohorts.Patients and Methods A total of 168 patients (201 knees) underwent medial UKA with the Oxford Partial Knee Twin-Peg. These patients were compared with a randomly selected group of 177 patients (189 knees) with primary Vanguard TKA. Patient demographics, Knee Society (KS) scores and range of movement (ROM) were compared between the two cohorts. Additionally, revision, re-operation and manipulation under anaesthesia rates were analysed.ResultsThe mean follow-up for UKA and TKA groups was 5.4 and 5.5 years, respectively. Six TKA (3.2%) versus three UKAs (1.5%) were revised which was not significant (p = 0.269). Manipulation was more frequent after TKA (16; 8.5%) versus none in the UKA group (p < 0.001). UKA patients had higher post-operative KS function scores versus TKA patients (78 versus 66, p < 0.001) with a trend toward greater improvement, but there was no difference in ROM and KS clinical improvement (p = 0.382 and 0.420, respectively).ConclusionWe found fewer manipulations, and higher functional outcomes for patients treated with medial mobile-bearing UKA compared with TKA. TKA had twice the revision rate as UKA although this did not reach statistical significance with the numbers available. Cite this article: Bone Joint J 2016;98-B(10 Suppl B):28–33.

Patient relevant outcomes of unicompartmental versus total knee replacement: systematic review and meta-analysis

“…A further 36 cohort studies were included in group 3. Of these studies including data comparisons between UKAs and TKAs,15 31 82 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 only five included data specifically in patients with anteromedial osteoarthritis 1585 99 103 111 Again, we saw some crossover in the data presented from the same unit in multiple papers, but the maximum number of implants was 26 418.…”

Unicompartmental knee replacement – Current perspectives

“…Recent studies have highlighted the advantages of UKR over total knee replacement (TKR) in patients with medial compartment OA, including reduced blood loss and risk of transfusion, 15,16 better restoration of physiological gait pattern, 17 shorter length of stay and a lower 30-day readmission rate, 18 better patientreported pain and function scores and forgotten joint scores. [19][20][21][22] Furthermore, a matched comparison of UKA and TKA based on NJR data including over 100,000 knee arthroplasties demonstrated that major medical complications, such as thromboembolism, infection, stroke and myocardial infarction occurred between a quarter and a half times less frequently in UKR than in TKR. Moreover, the mortality was significantly lower for UKR.…”

Total versus partial knee replacement in patients with medial compartment knee osteoarthritis: the TOPKAT RCT

“…45 Potential advantages of undergoing a PKR over a TKR for patients with medial compartment OA have been discussed in several registry and cohort studies. For example, studies have demonstrated reduced blood loss and risk of transfusion at the time of operation; 48,49 shorter length of stay and a lower 30-day re-admission rate; 50-52 more cost-effective, 53,54 better restoration of physiological gait pattern; 55 and better patient-reported pain and function scores and forgotten joint scores [56][57][58][59][60] for PKR compared with TKR. In addition, PKR has been reported to be more cost-effectiveness, 53,54 have lower incidence of medical complications, such as thromboembolism, infection, stroke and myocardial infarction, and lower mortality rates than TKR.…”