An Analysis Ten-year Results Of The ASR XL Acetabular System:A Single-centre Investigation From China Retrieval

Background:The revision rate of articular surface replacement(ASR)implants con-tinues to rise in China because of metal debris.However,there are few reports on the clinical results of ASR implants with prolonged follow-up time in China.This study in-vestigated the clinical outcomes and the risk factors of revision surgery in patents with ASR implants.Methods:In total,74 patients(74 hips)who underwent primary total hip arthroplasty(THA)with ASR implants over the past 4 to 10 years were retrospectively analyzed.Relevant clinical,radiographic,Contrast-enhanced ultrasound and biochemical data were examined.Results:The average follow-up time were 88.46(range 23-114)months and the ASR implants of 18 hips(24.3%)were revised.Patients who received revision surgery had worse joint function with significantly lower HHS and WOMAC index than non-revision patients(61.11±6.68 vs 85.30±9.16,p<0.001;61.00±3.83 vs 79.04±14.49,p<0.001;respectively).Higher acetabular abduction angle,serum Co and Cr concentra-tion were significantly relevant to worse joint function as measured by HSS(p=0.018,0.009,0.043,respectively).Contrast-enhanced ultrasound result shows in this study pa-tients with groin pain,the lesions around the prosthesis could be detected with high per-fusion compared with the surrounding normal tissues.ROC curve analysis was applied to categorize the optimal cutoff values of acetabular abduction angle,serum Cr and Co concentration for revision surgery,which were settled as 47.80°,98.44μg/L and 6.95μg/L,respectively.Overall survival of the prostheses with high acetabular abduc-tion angle(>47.80°,HR=70.145,95%CI 1.558-3158.213,p=0.029),high serum Cr con-centration(98.44μg/L,HR=58.956,95%CI 1.294-2685.203,p=0.036)and high serum Co concentration(>6.95μg/L,HR=179.511,95%CI 2.360-13656.941,p=0.019)de-creased significantly than the lower groups.Conclusions:Evaluation of the DePuy ASR XL articulation demonstrated increased rates of revision following a longer follow-up period.High acetabular abduction angle,serum Cr and Co concentration corre-lated with worse clinical outcomes and high revi-sion rate.Therefore,we advocate that patients with DePuy ASR XL implants be fol-lowed up more closely than those with other implants,espe-cially with high acetabular abduction angle,serum Cr or Co concentration.