Oxford phase 3 unicondylar knee arthroplasty through a minimally invasive approach: long-term results

Abstract

Purpose Surgical treatment options for medial compartment osteoarthritis of the knee include high tibial osteotomy, total knee arthroplasty or unicompartmental knee arthroplasty (UKA), depending on the patient's age, level of physical activity and the degree of deformity. Methods In this study, we evaluated the long-term results of patients who underwent the Oxford cemented meniscalbearing unicondylar knee prosthesis through a minimally invasive approach including a clinical, functional and radiographic assessment. Results Favourable clinical and radiological outcomes were registered overall at ten years after surgery. Overall results of UKA according to the American Knee Society (AKS) using Insall's criteria showed an excellent or good outcome for 492 knees (96.28 %), fair for 11 (2.15 %) and poor for eight (1.57 %) in the post-operative long term. Conclusions We believe that with appropriate surgical technique, patient selection, prosthetic design and specific training, surgeons should achieve good outcomes with the added advantages of a minimally invasive approach. High volume for this technique is important in our opinion.

Evidence-Based Indications for Mobile-Bearing Unicompartmental Knee Arthroplasty in a Consecutive Cohort of Thousand Knees

“…If surgeons do small numbers of UKR or have UKR 276 utilisation of less than 20% data from the National Joint Registry has shown the failure rate 277 increases [20]. This further supports the recommendation that if surgeons want to use mobile-278 bearing UKR they should base their indications on the pathoanatomy and ignore the contra-279 indications proposed by Kozinn and Scott [21][22][23][24][25][26]. 280…”

“…The limitations are that is that this is a designer series and the results 282 observed may not be representative, however similar results have been published at 283 independent centres at shorter follow up providing further support for using broad indications 284 for mobile-bearing UKR [22][23][24][25]27]. A further limitation is that, whilst all comparisons were 285 appropriately powered, larger subgroups of patients, with more data at longer term follow up 286 would increase the confidence in the observations made.…”

Radiological Decision Aid to determine suitability for medial unicompartmental knee arthroplasty

“…There are also multiple published or presented series from surgeons who use UKA for about half of their knee arthroplasties in which the Oxford Phase 3 UKA has achieved a ten-year survival of around 95%. 23 , 31 - 33 Analysis of data from the National Joint Registry of England and Wales demonstrates that surgeons undertaking the Oxford UKA in less than 20% of knee arthroplasties, and in particular less than 10%, have a high revision rate, partly because the number is small, and partly because they are using the wrong indications. 1 At 20% and above the revision rate is acceptable, however, best results are achieved when surgeons undertake the Oxford UKA in about half of knee arthroplasties.…”

Mobile-bearing medial unicompartmental knee arthroplasty restores limb alignment comparable to that of the unaffected contralateral limb

“…2013). However, there is no consensus regarding what the ideal postoperative alignment is after medial UKA; it is generally stated and assumed that alignment is restored to the pre-disease status, but thus far there has been no supporting evidence for this.…”