Sebastian Peers1, James E Moravek1, Matthew D Budge1, Michael D Newton2, Michael D Kurdziel3, Kevin C Baker4, J Michael Wiater5. 1. Department of Orthopaedic Surgery, Beaumont Health System, Royal Oak, MI, USA. 2. Department of Orthopaedic Research, Beaumont Health System, Royal Oak, MI, USA. 3. Department of Orthopaedic Surgery, Beaumont Health System, Royal Oak, MI, USA; Department of Orthopaedic Research, Beaumont Health System, Royal Oak, MI, USA. 4. Department of Orthopaedic Research, Beaumont Health System, Royal Oak, MI, USA; Department of Surgery, Oakland University-William Beaumont School of Medicine, Rochester, MI, USA. 5. Department of Orthopaedic Surgery, Beaumont Health System, Royal Oak, MI, USA; Department of Surgery, Oakland University-William Beaumont School of Medicine, Rochester, MI, USA. Electronic address: mwiater@beaumont.edu.
Abstract
BACKGROUND: Although short-term outcomes of reverse total shoulder arthroplasty have been promising, long-term success may be limited due to device-specific complications, including scapular notching. Scapular notching has been explained primarily as mechanical erosion; however, the generation of wear debris may lead to further biologic changes contributing to the severity of scapular notching. METHODS: A 12-station hip simulator was converted to a reverse total shoulder arthroplasty wear simulator subjecting conventional and highly cross-linked ultra-high-molecular-weight polyethylene humeral liners to 5 million cycles of alternating abduction-adduction and flexion-extension loading profiles. RESULTS: Highly cross-linked polyethylene liners (36.5 ± 10.0 mm(3)/million cycle) exhibited significantly lower volumetric wear rates compared with conventional polyethylene liners (83.6 ± 20.6 mm(3)/million cycle; P < .001). The flexion-extension loading profile exhibited significantly higher wear rates for conventional (P < .001) and highly cross-linked polyethylene (P < .001) compared with the abduction-adduction loading profile. Highly cross-linked wear particles had an equivalent circle diameter significantly smaller than wear particles from conventional polyethylene (P < .001). CONCLUSIONS: Highly cross-linked polyethylene liners significantly reduced polyethylene wear and subsequent particle generation. More favorable wear properties with the use of highly cross-linked polyethylene may lead to increased device longevity and fewer complications but must be weighed against the effect of reduced mechanical properties.
BACKGROUND: Although short-term outcomes of reverse total shoulder arthroplasty have been promising, long-term success may be limited due to device-specific complications, including scapular notching. Scapular notching has been explained primarily as mechanical erosion; however, the generation of wear debris may lead to further biologic changes contributing to the severity of scapular notching. METHODS: A 12-station hip simulator was converted to a reverse total shoulder arthroplasty wear simulator subjecting conventional and highly cross-linked ultra-high-molecular-weight polyethylene humeral liners to 5 million cycles of alternating abduction-adduction and flexion-extension loading profiles. RESULTS: Highly cross-linked polyethylene liners (36.5 ± 10.0 mm(3)/million cycle) exhibited significantly lower volumetric wear rates compared with conventional polyethylene liners (83.6 ± 20.6 mm(3)/million cycle; P < .001). The flexion-extension loading profile exhibited significantly higher wear rates for conventional (P < .001) and highly cross-linked polyethylene (P < .001) compared with the abduction-adduction loading profile. Highly cross-linked wear particles had an equivalent circle diameter significantly smaller than wear particles from conventional polyethylene (P < .001). CONCLUSIONS: Highly cross-linked polyethylene liners significantly reduced polyethylene wear and subsequent particle generation. More favorable wear properties with the use of highly cross-linked polyethylene may lead to increased device longevity and fewer complications but must be weighed against the effect of reduced mechanical properties.
Authors: Richard S Page; Angela C Alder-Price; Sophia Rainbird; Stephen E Graves; Richard N de Steiger; Yi Peng; Carl Holder; Michelle F Lorimer; Stephen D Gill Journal: Clin Orthop Relat Res Date: 2022-06-28 Impact factor: 4.755