Topographic anatomy and morphometry of the metacarpus and phalanges in the adult bactrian camel (Camelus bactrianus)

Fourteen specimens of the metacarpus and digits of the forelimb of the adult bactrian camel were examined by means of radiography, computerised tomography (CT), gross anatomy and morphometry. Its metacarpal bone is approximately slender and with a long shaft. Two digits are present, the third and fourth are fully developed; each digit has 3 phalanges and 2 proximal sesamoid bones. Under the phalanges of the forefoot, it is a well-developed digital pad which has 3 fat cushions (central, axial and abaxial) and an elastic fibrous cushion breaths phalanges of each digit. The gap of digit joints in radiograph is approximately 6-8 mm, the proximal articular facet area in digital joints is much larger than that of the corresponding distal. The relative density of phalanges in digit III is slightly larger than that of the digit IV, but the weight and volume of phalanges in digit III is slightly smaller than that of the digit IV, respectively. The relative density of axial proximal sesamoid is slightly smaller than that of the abaxial, the weight and volume of axial proximal sesamoid is larger than those of the abaxial, respectively. The distal half of proximal phalanx and middle phalanx are obviously oblique.