Histological changes during fracture repair with hydroxyapatite fibrillar collagen implants in calves

Male calves (18) were subjected to mid-shaft transverse metatarsal fracture s and divided equally into 2 groups. Group 1 was kept as control whereas in group 2, 3 cm long hydroxyapatite fibrillar collagen implant was impregnat ed in the medullary cavity. The operated limb was immobilized with plaster cast supported with aluminum splints, Full thickness bone pieces were colle cted from the fractured repair site under local analgesia on 30, 60 and 90 days of fracture from the animals of groups 1 and 2 both and subjected to h istological studies. Use of hydroxyapatite fibrillar collagen implant initi ated the osteoid formation at 40 days, osteon formation accompanied with re sorption of the implant at 60 days and establishment of Haversian system (c ompact bone) at 90 days revealing a faster rate of healing with the use of he implant as compared to those of the control animals which showed osteoid s even up to 90 days with little lamellar organization.