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Evaluation of in vivo wear of vitamin E-diffused highly crosslinked polyethylene at five years: a multicentre radiostereometric analysis study.
Galea, VP, Connelly, JW, Shareghi, B, Kärrholm, J, Sköldenberg, O, Salemyr, M, Laursen, MB, Muratoglu, O, Bragdon, C, Malchau, H
The bone & joint journal. 2018;(12):1592-1599
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Abstract
AIMS: The primary aim of this study was to compare the wear properties of vitamin E-diffused, highly crosslinked polyethylene (VEPE) and one formulation of moderately crosslinked and mechanically annealed ultra-high molecular weight polyethylene (ModXLPE) in patients five years after primary total hip arthroplasty (THA). The secondary aim was to assess the clinical results of patients treated with VEPE by evaluating patient-reported outcome measures (PROMs), radiological evidence of fixation, and the incidence of mechanical failure. PATIENTS AND METHODS A total of 208 patients (221 THAs) from four international centres were recruited into a prospective study involving radiostereometric analysis (RSA) and the assessment of clinical outcomes. A total of 193 hips (87%) were reviewed at the five-year follow-up. Of these, 136 (70%) received VEPE (vs ModXLPE) liners and 68 (35%) received ceramic (vs metal) femoral heads. PROMs and radiographs were collected preoperatively and at one, two, and five years postoperatively. In addition, RSA images were collected to measure PE wear postoperatively and at one, two, and five years after surgery. RESULTS We observed similar bedding in one year postoperatively and wear two years postoperatively between the two types of liner. However, there was significantly more penetration of the femoral head in the ModXLPE cohort compared with the VEPE cohort five years postoperatively (p < 0.001). The only variables independently predictive of increased wear were ModXLPE (vs VEPE) liner type (β = 0.22, p = 0.010) and metal (vs ceramic) femoral head (β = 0.21, p = 0.013). There was no association between increased wear and the development of radiolucency (p = 0.866) or PROMs. No patient had evidence of osteolysis. CONCLUSION Five years postoperatively, patients with VEPE (vs ModXLPE) and ceramic (vs metal) femoral heads had decreased wear. The rates of wear for both liners were very low and have not led to any osteolysis or implant failure due to aseptic loosening.
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VASO (Vitamin D and Arthroplasty Surgery Outcomes) study - supplementation of vitamin D deficiency to improve outcomes after total hip or knee replacement: study protocol for a randomised controlled feasibility trial.
Morrison, RJM, Bunn, D, Gray, WK, Baker, PN, White, C, Rangan, A, Rankin, KS, Reed, MR
Trials. 2017;(1):514
Abstract
BACKGROUND Vitamin D deficiency has been linked to poor outcomes after total hip replacement (THR) or total knee replacement (TKR), including lower patient-reported outcome measures (PROMs), peri-prosthetic infection and longer hospital stay. We present a randomised feasibility trial protocol designed to prospectively investigate the influence of vitamin D testing, and subsequent supplementation for deficiency, prior to THR/TKR. METHODS/DESIGN One hundred adult patients undergoing primary THR/TKR for osteoarthritis at two NHS hospital trusts in North East England will be recruited. Exclusion criteria include lack of mental capacity, revision surgery, participants already taking vitamin D/calcium supplements, or a known contraindication to vitamin D treatment. Participants will be ineligible for the trial if they have an estimated glomerular filtration rate < 30 ml/minute. We will measure patients' vitamin D levels at baseline, and those identified as deficient (vitamin D < 50 nmol/L) will be randomised to receive either vitamin D supplementation or no supplementation prior to, and for 6 months following, surgery. Patients with a normal vitamin D level (≥50 nmol/L) will receive no supplementation. Vitamin D levels will be rechecked on the day of surgery and again at 6 months. Patients will also complete a lifestyle questionnaire, as well as the Oxford hip or knee and EQ-5D-3 L PROM questionnaires, at baseline and at 6 months following surgery. The aims are to determine the feasibility of the methodology and to gather data to inform the conduct of a future, larger trial to investigate if supplementation with vitamin D, in those who are deficient, prior to THR/TKR improves outcomes as measured by PROM scores. DISCUSSION Previous reports have measured vitamin D levels and correlated this to outcome, but we can find no randomised trial in which researchers investigated the effect of supplementation. The aim of this trial is to determine if vitamin D deficiency is a modifiable risk factor for poor outcome after THR/TKR. TRIAL REGISTRATION ISRCTN Registry, ISRCTN14533082 . Registered on 3 April 2017.
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More than 50% reduction of wear in polyethylene liners with alumina heads compared to cobalt-chrome heads in hip replacements: a 10-year follow-up with radiostereometry in 43 hips.
Dahl, J, Snorrason, F, Nordsletten, L, Röhrl, SM
Acta orthopaedica. 2013;(4):360-4
Abstract
BACKGROUND AND PURPOSE Excessive wear of acetabular liners in hip replacements may lead to osteolysis and cup loosening. Different head materials are currently used. We measured differences in wear between alumina and cobalt-chrome heads with the same polyethylene liner. PATIENTS AND METHODS 39 patients (43 hips) with osteoarthritis were included in a study with 10-year follow-up. Wear was measured as proximal and 3D penetration of the head in the liner with radiostereometry (RSA). All the patients were followed clinically with Harris hip score (HHS) for up to 10 years. Radiolucent lines and osteolytic lesions were assessed on plain radiographs. RESULTS With alumina heads, proximal wear (95% CI) after 10 years was 0.62 (0.44-0.80) mm as compared to 1.40 (1.00-1.80) mm in the cobalt-chrome group. For 3D wear, the results were 0.87 (0.69-1.04) mm for alumina heads and 1.78 (1.35-2.21) mm for cobalt-chrome heads. Median (range) HHS was 98 (77-100) in the alumina group and it was 93 (50-100) in the cobalt-chrome group (p = 0.01). We found no difference in osteolysis between the groups. INTERPRETATION We found better wear properties with alumina heads than with cobalt-chrome heads. We recommend the use of alumina heads in patients in whom a high wear rate might be anticipated.
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Component positioning in primary total hip replacement: a prospective comparative study of two anterolateral approaches, minimally invasive versus gluteus medius hemimyotomy.
Mouilhade, F, Matsoukis, J, Oger, P, Mandereau, C, Brzakala, V, Dujardin, F
Orthopaedics & traumatology, surgery & research : OTSR. 2011;(1):14-21
Abstract
INTRODUCTION One factor of implant survivorship in total hip replacement (THR) is the quality of implant choice and positioning. The purported advantages of minimally invasive approaches are faster recovery, shorter hospital stay and less per-operative blood loss. On the other hand, there have been many reports of higher complication rates, and doubts as to the quality of implant positioning. HYPOTHESIS The quest to minimize tissue damage is at the cost of THR positioning quality. OBJECTIVES To assess implant positioning in a prospective comparative continuous multicenter series. PATIENTS AND METHODS Between 2008 and 2009, a prospective comparative study was conducted on a continuous series of 141 THRs. Ninety-two were performed in two centers, using a minimally invasive Watson-Jones approach; the other 49, performed in a 3rd center, used an anterolateral approach with anterior hemimyotomy. The surgeons were in all cases experienced in their technique. Short-term follow-up comprised clinical and functional (Postel Merle d'Aubigné (PMA), Harris, SF12, WOMAC) and biological assessment (serum creatine phosphokinase (CPK), myoglobinemia, hematocrit) and analysis of complications and of implant positioning on X-ray and CT-scan. RESULTS On the Watson-Jones approach, surgery time was longer; day-1 analgesic administration was lower; PMA, Harris and WOMAC scores were better at 6 weeks; and CPK levels were lower at 24 and 48hours. There were no significant differences on the other clinical and biological criteria. Implant positioning analysis revealed significantly greater combined anteversion and greater variation in acetabular inclination mean with the Watson-Jones approach, but no differences in cup positioning, femoral stem positioning, or limb length discrepancy. DISCUSSION The minimally invasive Watson-Jones approach provided faster recovery and less muscular damage. However, implant positioning was less precise in terms of acetabular cup inclination. LEVEL OF EVIDENCE Level III. Prospective, comparative, non-randomized.