Acta Medica Okayama volume75 issue1
2021-02 発行

The Thickness of the Medial Wall of the Acetabulum Prevents Acetabular Fracture during the Insertion of a Cementless Cup in Total Hip Arthroplasty: A Biomechanical Study

Sanki, Tomoaki Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
Tetsunaga, Tomonori Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences ORCID Kaken ID
Furumatsu, Takayuki Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kaken ID publons
Yamada, Kazuki Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
Kawamura, Yoshi Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
Ozaki, Toshifumi Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kaken ID publons researchmap
Publication Date
2021-02
Abstract
Intra-operative acetabular fracture is a total hip arthroplasty complication that can occur during cementless cup insertion, especially in osteoporotic patients. We conducted this biomechanical study to investigate the impact resistance of the acetabulum with simulated bones of different density by drop-weight impact testing. Low- and high-density polyurethane foam blocks were used as osteoporotic and healthy bone models, respectively. Polyurethane blocks were used as the acetabular cancellous bone. Composite sheets were used as the acetabu-lum’s medial cortex. The testing revealed that the osteoporotic bone model’s impact resistance was significantly lower than that the healthy bone model’. In the healthy bone model, even thin acetabular cancellous bone with ≥ 1 mm acetabulum medial cortex was less likely to fracture. In the osteoporotic bone model, fracture was pos-sible without ≥ 1 mm medial cortex of the acetabulum and thick acetabular cancellous bone. Although impac-tion resistance differs due to bone quality, the impaction resistance in this osteoporotic bone model was equiv-alent to that healthy bone model’s when a thick medial wall was present. To avoid intra-operative acetabulum fracture, surgeons should consider both the bone quality and the thicknesses of the medial cortex and acetabu-lar cancellous bone.
Document Type
Original Article
Keywords
intra-operative acetabular fracture
drop weight impact testing
total hip arthroplasty
impact resistance
Link to PubMed
75_1_71.pdf 4.77 MB