The Journal of Bone and Joint Surgery, Vol 67, Issue 1 105-112, Copyright © 1985 by Journal of Bone and Joint Surgery, Inc
A roentgenographic, biomechanical, and histological evaluation of vascularized and non-vascularized segmental fibular canine autografts
PC Dell, H Burchardt and FP Glowczewskie
Advocates of vascularized bone grafts believe that these grafts should have
a decreased time to graft-host union, and that they should be mechanically
stronger than conventional (non-vascularized) grafts. The objectives of the
present study were to determine the rate and pattern of repair in
vascularized autogenous cortical bone grafts, to determine the mechanical
strength of the grafts, and to correlate the mechanical strength with the
biological repair. Forty-nine adult male mongrel dogs were divided into six
groups to evaluate conventional (non-vascularized), cuff
(periosteal-encased, non-vascularized), and vascularized segmental grafts.
The fibula was the site of experimentation and all grafts were
four-centimeter cortical segments. The vascularized and conventional grafts
were analyzed at two, six, twelve, and twenty-four weeks. The cuff grafts
were analyzed at twenty-four weeks and were compared with conventional
grafts to assess the effect of the periosteal soft tissue. Roentgenograms
were made every two weeks to evaluate the time to union. The mechanical
strength of each graft was assessed by determining rapid torsional load to
failure. Biological repair was assessed by tetracycline labeling for
new-bone formation and by microradiographic techniques for porosity and
cross-sectional areas. The study showed that conventional and cuff grafts
were similar in terms of mechanical and biological repair at six months. At
all sampling intervals, the vascularized grafts exhibited histological
findings that were consistent with viability. The conventional and
vascularized grafts underwent different mechanisms of repair. The
conventional, non-vascularized grafts healed by peripheral and internal
resorption followed by callus encasement and osteonal remodeling.(ABSTRACT
TRUNCATED AT 250 WORDS)