Implantation of hydroxyapatite-lignin in the medullary canal of rabbits: macroscopic and difractografic evaluation

Objective. Macroscopically and diffractografically evaluate bone response to hydroxyapatite - lignin compound implanted in rabbit tibial medullary canal. Materials and methods. 20 New Zealand rabbits were used. Each of their left tibias was treated with the compound; the right tibias were not treated, serving as control. Bone fracture of approximately 4 mm in diameter in the lateral proximal tibia was performed, reaching the medullary canal. From the compound, 1000 mg were dissolved in 10 drops of saline solution using part of the mass to cover the twisted end of the intra-medullary pin, (Schanz steel F 138, size 2.5 mm for cortical bone) and the rest was introduced in the medullary canal of the group treated with the help of a catheter size 16 and disposable syringe. After introduction of 7 cm in length of the pin in the medullary canal, the anatomical blueprint was closed. The same was done in the control tibias, without use of the compound. Macroscopic and difractographic evauation of the medullary content which grew at the base of the pins was assessed at eight, 30, 60, 90 and 120 days post-surgery. Results. Each macroscopic evaluation date showed that the tendency of bone marrow in the treated rabbits was to regenerate and lose compound visibility, which was shown through X-ray diffraction, where crystalline tissue was found to be compatible with the mineral component of the bone. Conclusion. The compound can lead bone formation of intra-medullary nail without affecting the regeneration of bone marrow.