Dorsal displacement of the rectum after proximal tail amputation and subsequent surgical repair by bilateral semitendinosus muscle transposition in a cat.

A 6-year-old cat underwent tail amputation at the sacrococcygeal joint and was evaluated 5 days later because of necrosis of the skin at the surgery site and tenesmus. Tail amputation had been necessary as a result of vehicular trauma. Neurologic examination of the cat revealed no abnormalities. Clinical evaluation and radiography confirmed dorsal displacement of the rectum as a result of removal of the tail and transected sacrocaudal and rectococcygeal musculature as well as muscles of the pelvic diaphragm. The rectum was dilated and filled with hard feces. To correct the dorsal displacement of the rectum, bilateral semitendinosus muscle transposition was performed to restore tissue to the void created by removal of the tail, sacrocaudal muscles, muscles of the pelvic diaphragm, and rectococcygeus muscle. The cat recovered uneventfully from surgery. No further displacement of the rectum occurred and no lameness attributable to bilateral transection of the semitendinosus muscles was noted during a 2-year follow-up period. To the authors' knowledge, dorsal displacement of the rectum after proximal tail amputation and its surgical correction in a cat have not been described previously. The favorable outcome in this case suggested that bilateral semitendinosus muscle transposition can safely be used to address large muscular defects at the level of the caudal aspect of the sacrum and the perineum in cats.