The five-year radiological results of the uncemented Oxford medial compartment knee arthroplasty

Abstract

This study reports on the first 150 consecutive Oxford cementless unicompartmental knee arthroplasties (UKA) performed in an independent centre (126 patients). All eligible patients had functional scores (Oxford knee score and high activity arthroplasty score) recorded pre-operatively and at two- and five-years of follow-up. Fluoroscopically aligned radiographs were taken at five years and analysed for any evidence of radiolucent lines (RLLs), subsidence or loosening. The mean age of the cohort was 63.6 years (39 to 86) with 81 (53.1%) males. Excellent functional scores were maintained at five years and there were no progressive RLLs demonstrated on radiographs. Two patients underwent revision to a total knee arthroplasty giving a revision rate of 0.23/100 (95% confidence interval 0.03 to 0.84) component years with overall component survivorship of 98.7% at five years. There were a further four patients who underwent further surgery on the same knee, two underwent bearing exchanges for dislocation and two underwent lateral UKAs for disease progression. This was a marked improvement from other UKAs reported in New Zealand Joint Registry data and supports the designing centre's early results.

Sport and physical activity following unicompartmental knee arthroplasty: a systematic review

“…In a recent study on 150 consecutive cementless UKAs, Hooper et al [ 15 ] were able to demonstrate a significant improvement according to the High Activity Arthroplasty Score following UKA (Table 3 ).…”

“…Thirteen of seventeen studies used validated activity scores to evaluate the pre- and post-operative level of physical activity. Ten of these studies reported a statistically significant improvement following UKA according to the UCLA activity score [ 51 ], the Tegner activity score [ 38 ] or the High Activity Arthroplasty Score [ 1 , 10 , 15 , 18 , 21 , 26 , 30 , 44 , 45 , 47 ] (Table 3 ).…”

“…Orthop. UCLA, Tegner, Heidelberg Sports Activity Score Before surgery 6.2 ± 1.3 4.1 ± 1.4 23.8 ± 18.5 6.3 ± 1.1 4.0 ± 1.0 29.3 ± 18.5 p < 0.01 p = 0.27 p < 0.01 Weston-Simons et al [ 17 ] BJJ Tegner Before surgery 2.2 ± 1.2 2.9 ± 1.2 p < 0.01 Walker et al [ 44 ] KSSTA UCLA, Tegner, Schulthess Clinic Activity Score Before surgery Before surgery Before onset of restricting symptoms 5.3 ± 2.3 2.9 ± 1.6 N/A 6.7 ± 1.5 3.5 ± 0.8 N/A p < 0.01 p < 0.01 N/A Walker et al [ 45 ] JOA UCLA, Tegner, Schulthess Clinic Activity Score Before surgery Before surgery Before onset of restricting symptoms 3.3 ± 1.5 2.0 ± 1.1 N/A 6.8 ± 1.5 3.8 ± 1.1 N/A p < 0.001 p < 0.001 N/A Hooper et al [ 15 ] BJJ High Activity Arthroplasty Score Before surgery 4.33 ± 2.5 10.55 ± 1.93 p < 0.001 Ho et al [ 14 ] J Knee Surg. UCLA Before onset of restricting symptoms 8.1 ± 1.5 7.4 ± 1.6 Not calculated JOA Journal of Arthroplasty; AMJSM American Journal of Sports Medicine; KSSTA ...…”

“…Orthop. 159 (178) 52.8 63.5 (range 36–86) Prospective 24 (range 1.47) 8/16 Medial Mobile Oxford (Zimmer Biomet, Bridgend, UK) Not specified Weston-Simons et al [ 47 ] BJJ 258 (265) 35.2 63.6 (range 32–90) Prospective 49.2 (range 6–99.6) 14/16 Lateral Mobile Oxford phase 3 domed unicompartmental knee prothesis (Zimmer Biomet, Bridgend, UK) Cemented Walker et al [ 44 ] KSSTA 45 (45) 42.2 60.1 (range 36–81) Retrospective 35.4 (range 24–51) 11/16 Lateral Mobile Oxford (Zimmer Biomet, Bridgend, UK) Cemented Walker et al [ 45 ] JOA 93 (109) 49.4 55 (range 26–60) Prospective 52.8 (range 27.6–100.8) 10/16 Medial Mobile Oxford phase 3 unicompartmental knee prosthesis (Zimmer Biomet, Bridgend, UK) Cemented Hooper et al [ 15 ] BJJ 126 (150) 53.1 63.6 (range 39–86) Prospective Minimum 60 11/16 Medial Mobile …”

Advantages of a Cementless Unicompartmental Knee Arthroplasty Approach

“…Bone-implant partial radiolucency was 7% and complete radiolucency was 0% in the cementless cases compared with 65% and 29%, respectively, in the cemented group. Hooper et al 44 independently confirmed these results. In a large multicenter study of more than 1000 knees undergoing cementless Oxford UKA, implant survival was 97.2% at 6 years with no increased complication rate compared with cemented UKA.…”