Taux d’usure et ostéolyse avec deux types de polyéthylène recuit hautement réticulé de deuxième génération en arthroplastie totale de la hanche : étude comparative rétrospective au recul minimum de cinq ans

Abstract

BackgroundAs no previous study has directly compared the linear wear rate in two types of second-generation annealed highly cross-linked polyethylene, we performed a retrospective study with a minimum of 5-year follow-up to assess primary arthroplasties in the: (1) wear rates; and (2) incidence of osteolysis of the two types of HXLPE. HypothesisThere was no significant difference in the linear wear rate and the incidence of osteolysis between the two types of second-generation annealed highly cross-linked polyethylene. Patients and methodsIn this single-center study, we reviewed 257 cases of primary cementless total hip arthroplasties between 2011 and 2015, which were performed with 32mm delta ceramic on second-generation annealed highly cross-linked polyethylene (X3 and E1 were used in 105 and 103 cases, respectively). The mean wear rate was evaluated using a computer-assisted method, and the incidence of osteolysis was evaluated based on the appearance of a localized area with loss of trabecular bone or cortical erosion adjacent to the implants during the latest follow-up. ResultsIn total, we evaluated 208 cases, followed postoperatively for over 5 years (mean, 6.1 years, range: 5.0–8.0). There were no significant differences between the two groups with respect to age (list in order of group X, group E, p-value) (61.2±12.3, 62.7±12.1, p=0.36), sex (ratio of male: 17.1 %, 14.6 %, p=0.61), body mass index (22.9±3.7, 22.8±4.0, p=0.91), pre- (49.9±14.8, 48.5±13.8, p=0.49) and postoperative (91.3±9.1, 92.7±7.0, p=0.23) Japanese Orthopaedic Association Hip Score, cup size (50.8±3.0, 50.9±2.2, p=0.70), cup inclination (38.7±4.8, 37.6±4.8, p=0.10), and cup anteversion (18.7±6.9, 18.5±7.6, p=0.80). The mean linear wear rates of the X3 and E1 groups were 0.057±0.039 (range: 0–0.16) and 0.054±0.037mm/year (range: 0–0.15), respectively (p=0.61). No osteolysis was found on the final plain radiographs in both groups. DiscussionThis study revealed that both types of highly cross-linked polyethylene have excellent linear wear rates and were equally safe to use. However, the difference between the two materials in terms of the long-term wear rate should be further validated. Level of evidenceIII; retrospective case control study.