The principal distinguishing features of the limb skeleton of the pig are the well-developed, weightbearing ulnae and fibulae and the complete metapodial and phalangeal complements in the paired accessory digits (Figs. 36.1 and 36.2), even though these fail to make contact with firm ground.
It will also be recalled that very few pigs live long enough to attain skeletal maturity.
The hooves resemble those of cattle and have a soft digital pad, or bulb, that is well demarcated from the wall and sole (Fig.
36.3). The short life span and the common practice of running pigs on concrete make hoof trimming rarely necessary.The limbs of pigs received little veterinary attention before it was recognized that articular disease (especially osteochondrosis) was relatively common. This stimulated a belated interest in the anatomy of the major joints and in the development of appropriate procedures for their injection. The causes of much articular pathology are uncertain. However, rapid weight gain beyond the ability of the immature skeleton to provide adequate support may result in articular cartilage breakdown and bone deformities. The use of concrete flooring may also be a factor.