A Review on the Hindlimb Bones in Animals and Birds

Abstract

The hindlimb bones play an important role in locomotion, body-weight support and maintenance of postural balance in animals and birds. This review summarises the gross anatomical, morphometric and functional characteristics of the hindlimb skeleton in wild animals, domestic species and avian species, based on the studies included in the manuscript. The hindlimb region comprises the os coxae, femur, patella, tibia, fibula, tarsal bones, metatarsals, phalanges and sesamoid bones. The reviewed studies indicate species-related variation in the morphology of the femur, tibia, patella, metatarsus and stifle joint among cattle, horses, camels, goats, sheep, dogs, deer, birds and other animals. Descriptions of the pelvic girdle, tarsal and metatarsal bones, femoral condyles, tibial extremities and stifle articulations show that hindlimb bones differ in shape, articular arrangement, fusion pattern and relative development across species. Morphometric observations also demonstrate variation in bone length, breadth, circumference, cortical thickness, condylar dimensions and articular surfaces according to species, sex and age, where these variables were examined. In avian species, the tibiotarsus and tarsometatarsus show distinctive fusion patterns that differ from those of mammals. Together, these observations provide a comparative anatomical basis for understanding locomotor adaptations and structural diversity of the pelvic limb. The review may be useful for radiographic interpretation, orthopaedic evaluation, diagnosis and management of locomotor disorders, and comparative anatomical teaching. It also compiles available gross and morphometric information that may support future veterinary anatomical, clinical and comparative morphological investigations on hindlimb bones in animals and birds. The synthesis remains descriptive and reflects the scope and measurements reported by the cited studies, without introducing additional experimental observations.