Bita Shareghi1, Per-Erik Johanson, Johan Kärrholm. 1. 1Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Abstract
BACKGROUND: In an earlier study with a 2-year follow-up of uncemented cups, we had reported low femoral-head penetration of vitamin E-infused highly cross-linked polyethylene liners (E1) compared with highly cross-linked liners without vitamin E (ArComXL). We studied the penetration rate of E1 compared with that of ArComXL, with a focus on changes occurring between 2 and 5 years after total hip arthroplasty. METHODS: In this randomized controlled study, we performed radiostereometric analysis of the penetration rateup to 5 years in 63 hips. RESULTS: During the total period of observation, the median proximal penetration for E1, 0.13 mm (mean, 0.11 mm [95% confidence interval (CI), 0.08 to 0.14 mm]), was lower than that for ArComXL, 0.20 mm (mean, 0.22 mm [95% CI, 0.17 to 0.26 mm]). The median proximal penetration rate between 2 and 5 years was 0.02 mm/yr (mean, 0.01 mm/yr [95% CI, 0.01 to 0.02 mm/yr]) for E1 and 0.04 mm/yr (mean, 0.04 mm/yr [95% CI, 0.03 to 0.05 mm/yr) for ArComXL. The corresponding median total (i.e., 3-dimensional resultant) penetration rates were 0.04 mm/yr (mean, 0.04 mm/yr [95% CI, 0.03 to 0.05 mm/yr]) for E1 and 0.07 mm/yr (mean, 0.08 mm/yr [95% CI, 0.06 to 0.10 mm/yr]) for ArComXL. CONCLUSIONS: From years 2 to 5, we observed increased penetration in both groups. The penetration rate was higher for ArComXL, resulting in more proximal and total penetration at 5 years than for E1. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.
RCT Entities:
BACKGROUND: In an earlier study with a 2-year follow-up of uncemented cups, we had reported low femoral-head penetration of vitamin E-infused highly cross-linked polyethylene liners (E1) compared with highly cross-linked liners without vitamin E (ArComXL). We studied the penetration rate of E1 compared with that of ArComXL, with a focus on changes occurring between 2 and 5 years after total hip arthroplasty. METHODS: In this randomized controlled study, we performed radiostereometric analysis of the penetration rate up to 5 years in 63 hips. RESULTS: During the total period of observation, the median proximal penetration for E1, 0.13 mm (mean, 0.11 mm [95% confidence interval (CI), 0.08 to 0.14 mm]), was lower than that for ArComXL, 0.20 mm (mean, 0.22 mm [95% CI, 0.17 to 0.26 mm]). The median proximal penetration rate between 2 and 5 years was 0.02 mm/yr (mean, 0.01 mm/yr [95% CI, 0.01 to 0.02 mm/yr]) for E1 and 0.04 mm/yr (mean, 0.04 mm/yr [95% CI, 0.03 to 0.05 mm/yr) for ArComXL. The corresponding median total (i.e., 3-dimensional resultant) penetration rates were 0.04 mm/yr (mean, 0.04 mm/yr [95% CI, 0.03 to 0.05 mm/yr]) for E1 and 0.07 mm/yr (mean, 0.08 mm/yr [95% CI, 0.06 to 0.10 mm/yr]) for ArComXL. CONCLUSIONS: From years 2 to 5, we observed increased penetration in both groups. The penetration rate was higher for ArComXL, resulting in more proximal and total penetration at 5 years than for E1. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.
Authors: Hannah Spece; Jaclyn T Schachtner; Daniel W MacDonald; Gregg R Klein; Michael A Mont; Gwo-Chin Lee; Steven M Kurtz Journal: J Arthroplasty Date: 2019-07-18 Impact factor: 4.757
Authors: Kristian Kjærgaard; Ming Ding; Carsten Jensen; Charles Bragdon; Henrik Malchau; Christina M Andreasen; Ole Ovesen; Christian Hofbauer; Søren Overgaard Journal: Bone Joint J Date: 2020-10 Impact factor: 5.082