Bone heals by bone. Fractured bone can be replaced to its original form without formation of scar. The process of fracture healing can occur in two ways. Primary bone healing occurs without callus formation and the secondary bone healing occurs with a callus precursor stage 1,2 . The major diaphyseal fracture models are from animals like mouse, rat, rabbit 3,4 . Although the bones of some animals (e.g. rat and sheep) differ physiologically from human bone (i.e. they do not undergo normal haversian remodellation), they have been widely used in orthopaedic research 4,5,6 . Ofloxacin is a synthetic chemotherapeutic antibiotic of the second generation fluoroquinolone. The fluoroquinolones interfere with DNA replication by inhibiting an enzyme complex called DNA gyrase. Recent studies have demonstrated a correlation between mammalian cell cytotoxicity of the quinolones and the induction of micronuclei 7 . As such some fluoroquinolones may cause injury to the chromosome of eukaryotic cells. It is not recommended for usage in children because of serious reversible and irreversible musculoskeletal adverse effects.