André Busch1, Marcus Jäger2, Stefan Klebingat3, Josef Baghdadi4, Thilo Flörkemeier5, Felix Hütter6, Thomas M Grupp7,8, Marcel Haversath2. 1. Department of Orthopaedics, Trauma and Reconstructive Surgery Marienhospital Mülheim an der Ruhr, Chair of Orthopaedics and Trauma Surgery University of Duisburg-Essen, Essen, Germany. andre.busch@uk-essen.de. 2. Department of Orthopaedics, Trauma and Reconstructive Surgery Marienhospital Mülheim an der Ruhr, Chair of Orthopaedics and Trauma Surgery University of Duisburg-Essen, Essen, Germany. 3. Institut für Medizintechnik und Forschungscampus STIMULATE, Otto-von-Guericke-Universität Magdeburg, Magdeburg, Germany. 4. Department of Orthopaedic Surgery, Hannover Medical School, Hannover, Germany. 5. Department für Orthopädie, Unfall- und Wiederherstellungschirurgie, Universitätsklinikum Halle (Saale), Ernst-Grube-Str. 40, 06114, Halle (Saale), Germany. 6. Department of Orthopaedics and Trauma Surgery, Elisabeth-Klinikum Olsberg, Olsberg, Germany. 7. Aesculap AG, Research and Development, 78532, Tuttlingen, Germany. 8. Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation, Campus Grosshadern, Ludwig Maximilians University Munich, Munich, Germany.
Abstract
BACKGROUND:Progressive oxidation of highly cross-linked ultra-high molecular weight (UHMPWE-X) liners is considered to be a risk factor for material failure in THA. Antioxidants such as vitamin E (alpha-tocopherol) (UHMWPE-XE) were supplemented into the latest generation of polyethylene liners. To prevent inhomogenous vitamin E distribution within the polymer, blending was established as an alternative manufacturing process to diffusion. The purpose of the present study was to investigate the in vivo wear behavior of UHMWPE-XE in comparison with conventional UHMWPE-X liners using virtual CAD-based radiographs. METHODS: Until now, 94 patients from a prospective, randomized, controlled, multicenter study were reviewed at 5-year follow-up. Of these, 51 (54%) received UHMWPE-XE and 43 (46%) UHMWPE-X liners. Anteroposterior pelvic radiographs were made immediately after surgery and at 1 and 5 years postoperatively. The radiographs were analyzed using the observer-independent analysis software RayMatch® (Raylytic GmbH, Leipzig, Germany). RESULTS: The mean wear rate was measured to be 23.6 μm/year (SD 13.7; range 0.7-71.8 μm). There were no significant differences between the two cohorts (UHMWPE-X: 23.2 μm/year vs. UHMWPE-XE: 24.0 μm/year, p = 0.73). Cup anteversion significantly changed within the 1st year after implantation independent from the type of polyethylene liner [UHMWPE-X: 18.2-23.9° (p = 0.0001); UHMWPE-XE: 21.0-25.5° (p = 0.002)]. No further significant changes of cup anteversion in both groups were found between year 1 and 5 after implantation [UHMWPE-X (p = 0.46); UHMWPE-XE (p = 0.56)]. CONCLUSION: The present study demonstrates that the addition of vitamin E does not adversely affect the midterm wear behavior of UHMWPE-X. The antioxidative benefit of vitamin E is expected to become evident in long-term follow-up. Cup anteversion increment by 5° within the 1st year is likely a result of the released hip flexion contracture resulting in an enhanced posterior pelvic tilt. Therefore, a reassessment of target values in acetabular cup placement might be considered.
RCT Entities:
BACKGROUND: Progressive oxidation of highly cross-linked ultra-high molecular weight (UHMPWE-X) liners is considered to be a risk factor for material failure in THA. Antioxidants such as vitamin E (alpha-tocopherol) (UHMWPE-XE) were supplemented into the latest generation of polyethylene liners. To prevent inhomogenous vitamin E distribution within the polymer, blending was established as an alternative manufacturing process to diffusion. The purpose of the present study was to investigate the in vivo wear behavior of UHMWPE-XE in comparison with conventional UHMWPE-X liners using virtual CAD-based radiographs. METHODS: Until now, 94 patients from a prospective, randomized, controlled, multicenter study were reviewed at 5-year follow-up. Of these, 51 (54%) received UHMWPE-XE and 43 (46%) UHMWPE-X liners. Anteroposterior pelvic radiographs were made immediately after surgery and at 1 and 5 years postoperatively. The radiographs were analyzed using the observer-independent analysis software RayMatch® (Raylytic GmbH, Leipzig, Germany). RESULTS: The mean wear rate was measured to be 23.6 μm/year (SD 13.7; range 0.7-71.8 μm). There were no significant differences between the two cohorts (UHMWPE-X: 23.2 μm/year vs. UHMWPE-XE: 24.0 μm/year, p = 0.73). Cup anteversion significantly changed within the 1st year after implantation independent from the type of polyethylene liner [UHMWPE-X: 18.2-23.9° (p = 0.0001); UHMWPE-XE: 21.0-25.5° (p = 0.002)]. No further significant changes of cup anteversion in both groups were found between year 1 and 5 after implantation [UHMWPE-X (p = 0.46); UHMWPE-XE (p = 0.56)]. CONCLUSION: The present study demonstrates that the addition of vitamin E does not adversely affect the midterm wear behavior of UHMWPE-X. The antioxidative benefit of vitamin E is expected to become evident in long-term follow-up. Cup anteversion increment by 5° within the 1st year is likely a result of the released hip flexion contracture resulting in an enhanced posterior pelvic tilt. Therefore, a reassessment of target values in acetabular cup placement might be considered.
Entities:
Keywords:
CAD-based wear analysis; Particle-induced osteolysis; Total hip arthroplasty; UHMWPE-XE
Authors: André Busch; Marcus Jäger; Sascha Beck; Alexander Wegner; Erik Portegys; Dennis Wassenaar; Jens Theysohn; Johannes Haubold Journal: BMC Musculoskelet Disord Date: 2022-06-28 Impact factor: 2.562