163.
Instability-Induced Periprosthetic Osteolysis Is Not Dependent on the
Fibrous Tissue Interface
Rune V. Madsen, Denis Nam , Aleksey Dvorzhinskiy, Mathias P Bostrom,
Anna Fahlgren
University of Copenhagen; , Hospital for Special Surgery, New York, USA; ,
Hospital for Special Surgery, New York, USA; , Hospital for Special Surgery,
New York, USA; , Linköping University, Linköping, Sweden
Background:
In the setting of implant motion, a fibrous tissue layer forms at
the bone-implant interface, leading to implant migration and peri-prosthetic
osteolysis. At the time of implant revision surgery, pro-resorptive signaling
cytokines are expressed in the peri-implant fibrous membrane. However, the
exact role of this fibrous tissue in causing peri-prosthetic osteolysis due to
instability remains unknown.
Purpose / Aim of Study:
The objective of this study was to determine the role
of the fibrous tissue layer in osteoclast activity and peri-prosthetic bone loss.
Materials and Methods:
We studied presence and absence of fibrous tissue in
our established rat model for instability induced osteolysis (total n=48). Micro-
CT and immunohistochemistry were used to determine whether fibrous tissue
is required for both osteoclast activity and peri-implant bone loss.
Findings / Results:
The amount of bone loss was increased by instability. The
presence of fibrous tissue had no effect on the amount of bone loss. There was
no enhanced effect in bone loss, when pressure and presence of fibrous tissue
was combined. Instability by pressure induced dramatic bone resorption in the
peri-prosthetic bone. The presence of fibrous tissue had no effect on the
amount of osteoclasts, neither was there a combined effect in the presence of
both pressure and fibrous tissue.
Conclusions:
The current animal model mimicked this scenario through a
compressed fibrous tissue membrane. However, the fibrous membrane had no
effect on osteoclast activity and bone loss. Our findings suggest that the bone
tissue surrounding an implant induces osteoclast differentiation and bone loss
due to mechanical factors, such as fluid flow and pressure, even in the absence
of a fibrous tissue membrane.
Deltager i konkurrencen om YODA’s ungdomsforskerpris
