DOS BULLETIN - Dansk Ortopædisk Selskab

2010-378_DOS nr. 3 2010 29/09/10 10:08 Side 126
Periosteal augmentation of allograft bone and its
effects on implant fixation
Jeppe Barckman, Jorgen Baas, Mette Sorensen,
Joan E. Bechtold, Kjeld Soballe
Orthopaedic Research Laboratory,
Department of Orthopaedic Surgery, Aarhus University Hospital;
Minneapolis Medical Research Foundations, Minneapolis MN USA
Background: Hip and knee arthroplasty can present surgeons with difficult
bone loss. The use of morselized allograft is a well-established way
of optimizing early implant fixation, but integration is not always complete
or immediate.
Purpose: We hypothesized that augmenting the allograft bone by adding
minced autograft periosteum could provide an added signal for
osteogenic differentiation, and possibly add pluripotent lining cells for
aiding initial bone healing. This was tested by comparison of early
implant fixation of the two groups.
Methods: Following approval of the Institutional Animal Care and use
Committee we implanted a cylindrical (10x6 mm) porous-coated Ti
implant in each distal femur of 12 dogs observed for 4 weeks. The
implants were surrounded by a circumferential gap of 2.5 mm impacted
with a standardized volume of morselized allograft. On the intervention
side, the morselized allograft was augmented by 1cm2 minced periosteum
harvested from the proximal tibia. The power in the study allowed
detection of relative differences of 30% T-test was applied, p-value <
0,05 considered statistically significant.
Findings: Biomechanical fixation tested by axial push- out revealed no
change in fixation with the use of periosteal augmentation. Control vs.
periosteal augmentation: Shear strength (MPa) 4,43 vs. 4,30 (p=0,788),
stiffness(MPa/mm) 20,12 vs. 19,42 (P=0,834) and energy
absorption(kJ/m2) 0,90 vs. 0,87 (P=0,619).
Conclusion: In this experimental model and implant conditions, augmentation
of the allograft bone by autograft periost did not improve
mechanical implant fixation. Other volumes of periosteum or local
(attached) flap of periosteum can be studied in the future, but the present
study does not support the use of periosteal augmentation of allograft
bone in clinical practice.
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