Differences between Medial and Lateral Digits with Respect to Length and Width of Distal Limb Bones in Cattle of Various Ages - A Radiographic Study

The digits of ten calves, ten heifers, ten young adult and ten old cows were radiographed and measured to investigate whether the medial and lateral digits differ in length. Palmarodorsal and plantarodorsal digital radiographs were taken at postmortem. A computer software program (Metron PXTM) was used to measure the length and width of the first (P1), second (P2) and third (P3) phalanges, the course of the metacarpal/metatarsal and interdigital axes, and three different total bone lengths. A P-value of 0.05 was used as the level of significance for comparison of bone lengths and widths.
The metacarpal/metatarsal condyles and P1 and P2 were generally longer in the lateral digit than in the medial digit. Depending on the age group, the bones of the lateral digit were longer in 65 to 99% of the forelimbs and in 74 to 95% of the hind limbs. In contrast, P3 was longer in the medial digit of 68% of the forelimbs and in 66% of the hind limbs.
The mean distance from the epiphyseal groove to the distal interphalangeal joint (total length 1) was significantly greater in the lateral digit than in the medial. Except in calves, the mean distance from the epiphyseal groove to the tip of P3 (total length 2) was also greater in the lateral digit, but the difference was not always significant ...