A minimally invasive model using a manual abrader to induce adhesions in th
e chicken's central digit is described. The flexor synovial sheath and the
profundus tendon were abraded with access through small flaps at the level
of the proximal and distal phalanges of the avian long toes. The birds were
divided into two groups according to the severity of the induced trauma. G
roup I birds received an abrasion injury and were euthanized to allow biome
chanical testing 5 weeks postoperatively. Group II birds had a more severe
abrasion and were euthanized similarly and tested 5 weeks after surgery. Re
sults were compared with nonsurgical controls. Long toe function was evalua
ted weekly by measuring (1) the range of active flexion of each interphalan
geal joint, resolved to total angular range; (2) the grasping ability on gr
aded-diameter perches; and (3) the flexion deficit of the long toe. Postmor
tem biomechanical properties of the adhesions were measured. There was a si
gnificant difference between the unoperated controls and abraded digits of
both groups in all parameters (p < 0.001). There was, in addition, a marked
change in most of the measured parameters between groups I and II. In grou
p I digits the functional and biomechanical deficit was less than group II.
In summary, this animal model of long-segment abrasive injury to the tendo
n and sheath is a simple and reproducible method to generate adhesions and
can be used for the evaluation of treatment modalities for adhesion prevent
ion.