Subchondral Bone Relative Area and Density in Human Osteoarthritic Femoral Heads Assessed with Micro-CT before and after Mechanical Embedding of the Innovative Multi-Spiked Connecting Scaffold for Resurfacing THA Endoprostheses: A Pilot Study

Mikołaj Dąbrowski; Piotr Rogala; Ryszard Uklejewski; Adam Patalas; Mariusz Winiecki; Bartosz Gapiński

doi:10.3390/jcm10132937

Subchondral Bone Relative Area and Density in Human Osteoarthritic Femoral Heads Assessed with Micro-CT before and after Mechanical Embedding of the Innovative Multi-Spiked Connecting Scaffold for Resurfacing THA Endoprostheses: A Pilot Study

J Clin Med. 2021 Jun 30;10(13):2937. doi: 10.3390/jcm10132937.

Authors

Mikołaj Dąbrowski¹, Piotr Rogala², Ryszard Uklejewski^{3

4}, Adam Patalas⁴, Mariusz Winiecki^{3

4}, Bartosz Gapiński⁵

Affiliations

¹ Adult Spine Orthopaedics Department, W. Dega University Hospital, Poznan University of Medical Sciences, 28 Czerwca 1956 Street 135/147, 61-545 Poznan, Poland.
² Institute of Health Sciences, Hipolit Cegielski State College of Higher Education, Card. Stefan Wyszyński Street 38, 62-200 Gniezno, Poland.
³ Construction Materials and Biomaterials, Institute of Materials Engineering, Kazimierz Wielki University, Karola Chodkiewicza Street 30, 85-064 Bydgoszcz, Poland.
⁴ Division of Technology Design/Laboratory of Bone Implants Research and Design, Institute of Mechanical Technology, Poznan University of Technology, Piotrowo Street 3, 60-965 Poznan, Poland.
⁵ Division of Metrology and Measurement Systems, Institute of Mechanical Technology, Poznan University of Technology, Piotrowo 3, 60-965 Poznan, Poland.

Abstract

The multi-spiked connecting scaffold (MSC-Scaffold) prototype is the essential innovation in the fixation of components of resurfacing total hip arthroplasty (THRA) endoprostheses in the subchondral trabecular bone. We conducted the computed micro-tomography (micro-CT) assessment of the subchondral trabecular bone microarchitecture before and after the MSC-Scaffold embedding in femoral heads removed during long-stem endoprosthesis total hip arthroplasty (THA) of different bone densities from 4 patients with hip osteoarthritis (OA). The embedding of the MSC-Scaffold in subchondral trabecular bone causes the change in its relative area (BA/TA, bone area/total area ratio) ranged from 18.2% to 24.7% (translating to the calculated density ρ_B relative change 11.1-14.4%, and the compressive strength S relative change 75.3-122.7%) regardless of its initial density (before the MSC-Scaffold embedding). The densification of the trabecular microarchitecture of subchondral trabecular bone due to the MSC-Scaffold initial embedding gradually decreases with the increasing distance from the apexes of the MSC-Scaffold's spikes while the spatial extent of this subchondral trabecular bone densification ranged from 1.5 to 2.5 mm (which is about half the height of the MSC-Scaffold's spikes). It may be suggested, despite the limited number of examined femoral heads, that: (1) the magnitude of the effect of the MSC-Scaffold embedding on subchondral trabecular bone densification may be a factor contributing to the maintenance of the MSC-Scaffold also for decreased initial bone density values, (2) the deeper this effect of the subchondral trabecular bone densification, the better strength of subchondral trabecular bone, and as consequence, the better post-operative embedding of the MSC-Scaffold in the bone should be expected.

Keywords: biomimetic fixation for resurfacing endoprostheses; micro-CT assessment; multi-spiked connecting scaffold (MSC-Scaffold); osteoarthritic hip; resected human femoral heads; subchondral trabecular bone density; subchondral trabecular bone relative area; surface replacement arthroplasty.