Tyagi, S. P.Tejender Kumar2019-02-022019-02-022017-11-23http://krishikosh.egranth.ac.in/handle/1/5810093343The present study was conducted to record the regional occurrence of long bone fractures in large animals, standardization of the technique of IILN in bovine tibia, designing a better anatomically contoured interlocking nail (AC ILN) and the in-vitro biomechanical evaluation of ILNs, and different bone-ILN constructs. The study over a period of 17 months revealed the regional incidence of long bone fractures as 12.87 % in cattle, 12.82 % in buffaloes and 23.33 % in equine with ‘fall from a height’ being the most common cause of fractures and the tibia in bovine and radius ulna in equine being the most common bone affected. Sex-wise, the overall incidences of fractures were higher in males (24.44 %) and age-wise, in juveniles (16.42 %) though the distribution of fractures were significantly more in females (81.03%). The technique of IILN was standardized on dry and freshly harvested intact and osteotomized bovine cadaveric tibial bones. The most suitable point of insertion of ILN in bovine tibial bone, the maximum lengths and widths of ILN that can be inserted in the bones and the most suitable direction of interlocking bolts were ascertained. As the study revealed unsuitability of thicker straight ILNs in maintaining normal anatomical alignment of osteotomized tibial bones, a better fitting AC ILN was designed and successfully utilized. The study revealed that an AC ILN with a single 80 cranio-caudal angle, 11 cm away from its distal end is the most suitable design for maintaining the osteotomized adult bovine tibial bones in the normal anatomic alignment. The biomechanical tests on straight and AC ILNs and different bone-ILN constructs revealed that 11 mm AC ILNs fixed using 6.0 mm interlocking bolts are better than straight using 6.0 mm bolts or AC ILNs fixed with 4.9 mm bolts as these provide significantly higher biomechanical strengtennullThesis