The thick layer of subcutaneous fat almost completely hides the junction between abdomen and pelvis, which is indicated only by a slight indentation above the fold of the flank.
The landmarks of the pelvic skeleton are not immediately visible, but the positions of the coxal and ischial tubers is easily palpable, which reveals the small size of the girdle in relation to the overall dimensions of the hindquarters.
The body and tuber of the ischium unite in very few pigs, and the unfused tuber is at risk of detachment by the pull of the powerful hamstring muscles that arise from it. Young sows are most commonly affected and are unable to rise when this happens; the very painful condition has no cure but slaughter.From a lateral view, the pelvic floor and the iliac shaft meet at an angle that approaches 180 degrees (Fig. 35.1) and create a large and oval pelvic inlet. The "vertical diameter" is maintained caudally, to intersect the part of the sacrum composed of yet unfused bones to allow some mobility. The pelvic floor slopes caudoventrally. The pelvic canal is a little higher than it is wide (Fig. 35.1). The slight inward bending of the ischial spines and presence of soft tissue structures narrow the canal. The slackening of the sacrosciatic ligament, which completes the lateral wall of the pelvic cavity, and of the joints of the girdle helps during farrowing.