LUMBOSACRAL DORSAL RAMI OF CAT

Abstract

The macroscopic anatomy of the lumbosacral dorsal rami of the cat (Felis domesticus) was studied by gross dissection. Six embalmed specimens were studied and observations were confirmed in a further 16 animals during surgical procedures. The L1-6 dorsal rami form 3 branches, lateral, intermediate and medial. The lateral branches supply the iliocostalis lumborum and become cutaneous over the back. The intermediate branches ramify in the longissiums lumborum, and are separated from the lateral branches by the lumbar intermuscular septum. The medial branches supply the multifidus and have a constant branch, the nerve to the intertransversarii mediales. The L7 dorsal ramus forms only a medial and an intermediate branch which supply the multifidus and longissimus lumborum, respectively. A nerve to the intertransversarii mediales is lacking at this level because this muscle has no origin from the L7 vertebra. The S1 and S2 dorsal rami each form 3 branches. Medial and lateral branches are distributed to the medial and lateral muscles of the tail. The middle branches from these levels form the ascending sacral trunk and accessory ascending sacral trunk. These nerves run rostrally into the dorsal lumbar region and are exclusively distributed to the lumbococcygeus muscle.