Trial Information

Physical Characteristics of Retrieved Massive Allografts

Allograft bone is the primary source of graft material for large skeletal defects resulting
from trauma, disease, oncological resection, or reconstruction of failed total joint
arthroplasties. The physical characteristics of such grafts after various intervals of
remodeling and incorporation in vivo have never been studied.

The purpose of this study is to obtain tissue from allografts retrieved at autopsy, at
amputation for oncological complications and from patients undergoing revision procedures
for failed allograft transplantation. We will evaluate the mechanical properties,
histomorphometric indices and presence of microfractures.

Our hypotheses are:

- histomorphometric parameters of porosity and microfracture density will predict
allograft strength,

- microfracture density will be correlated with time in vivo and allograft strength,

- the rate of host-allograft nonunion and fracture will correlate with radiation therapy
and chemotherapy.

The retrieved tissue will be processed using standard undecalcified histology and
quantitatively assessed for degree of incorporation, allograft porosity, and microfracture
density. The biomechanical characteristics of the bulk allograft and allograft-host
junction will be quantified and compared to allograft bone prior to transplantation.