Gulraj S Matharu1, Andrew Judge2, David W Murray1, Hemant G Pandit3. 1. Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Nuffield Orthopaedic Centre, Oxford, United Kingdom. 2. Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Nuffield Orthopaedic Centre, Oxford, United Kingdom; MRC Lifecourse Epidemiology Unit, Southampton General Hospital, University of Southampton, Southampton, United Kingdom; Musculoskeletal Research Unit, University of Bristol School of Clinical Sciences, Bristol, United Kingdom. 3. Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Nuffield Orthopaedic Centre, Oxford, United Kingdom; Leeds Institute of Rheumatic and Musculoskeletal Medicine (LIRMM), Chapel Allerton Hospital, Leeds, United Kingdom.
Abstract
BACKGROUND: Trabecular metal (TM)-coated acetabular components are increasingly used in both primary and revision total hip arthroplasty (THA). However, previous studies assessing TM acetabular components have been small single-center cohorts with most lacking a control group. We compared revision rates following primary THA between TM and non-TM-coated acetabular components. METHODS: A retrospective observational study was performed using National Joint Registry data, which included primary THAs with the same cementless acetabular component (either TM or non-TM coated). TM and non-TM implants were matched for multiple potential confounding factors using propensity scores. Outcomes following primary THA (revision for all-cause acetabular indications, aseptic acetabular loosening, and infection) were compared between matched groups using competing risk regression analysis. RESULTS: In 18,200 primary THAs (9100 TM and 9100 non-TM), the overall prevalence of acetabular revision, revision for aseptic acetabular loosening, and septic revision was 1.2%, 0.13%, and 0.59% respectively. Five-year revision rates for all-causes (1.0% vs 1.8%, sub-hazard ratio [SHR] 0.57, 95% confidence interval [CI] 0.43-0.76, P < .001), aseptic acetabular loosening (0.1% vs 0.2%, SHR 0.35, 95% CI 0.14-0.90, P = .029), and infection (0.5% vs 0.9%, SHR 0.51, 95% CI 0.34-0.76, P = .001) were all lower in TM compared with non-TM implants. CONCLUSION: Following primary THA, TM-coated acetabular implants had a reduced risk of both aseptic and septic revision compared with non-TM implants. Although absolute differences in revision risk were small, they may be clinically significant if TM designs were implanted in more complex cases.
BACKGROUND: Trabecular metal (TM)-coated acetabular components are increasingly used in both primary and revision total hip arthroplasty (THA). However, previous studies assessing TM acetabular components have been small single-center cohorts with most lacking a control group. We compared revision rates following primary THA between TM and non-TM-coated acetabular components. METHODS: A retrospective observational study was performed using National Joint Registry data, which included primary THAs with the same cementless acetabular component (either TM or non-TM coated). TM and non-TM implants were matched for multiple potential confounding factors using propensity scores. Outcomes following primary THA (revision for all-cause acetabular indications, aseptic acetabular loosening, and infection) were compared between matched groups using competing risk regression analysis. RESULTS: In 18,200 primary THAs (9100 TM and 9100 non-TM), the overall prevalence of acetabular revision, revision for aseptic acetabular loosening, and septic revision was 1.2%, 0.13%, and 0.59% respectively. Five-year revision rates for all-causes (1.0% vs 1.8%, sub-hazard ratio [SHR] 0.57, 95% confidence interval [CI] 0.43-0.76, P < .001), aseptic acetabular loosening (0.1% vs 0.2%, SHR 0.35, 95% CI 0.14-0.90, P = .029), and infection (0.5% vs 0.9%, SHR 0.51, 95% CI 0.34-0.76, P = .001) were all lower in TM compared with non-TM implants. CONCLUSION: Following primary THA, TM-coated acetabular implants had a reduced risk of both aseptic and septic revision compared with non-TM implants. Although absolute differences in revision risk were small, they may be clinically significant if TM designs were implanted in more complex cases.
Authors: Inari Laaksonen; Natalie Hjelmberg; Kirill Gromov; Antti E Eskelinen; Ola Rolfson; Henrik Malchau; Anders Troelsen; Keijo T Mäkelä; Maziar Mohaddes Journal: Acta Orthop Date: 2020-07-03 Impact factor: 3.717