Innervation of the pelvic limb of the adult ostrich (Struthio camelus)

The pelvic limb of the ostrich is innervated by the lumbar and sacral plexuses. The lumbar plexus gave rise to several nerves (N.s) including, N. coxalis cranialis, lateral and cranial femoral cutaneous N.s, N. femoralis, cranial, caudal and medial crural cutaneous N.s, and N. obturatorius. The remaining nerves emanated from the sacral plexus. The N. iliotibial, N. ischiofemoralis, N. iliofibularis, and N. coxae caudalis were distributed in the thigh, while the N. ischiadica, which terminated as the tibial and fibular N.s that innervated the leg and foot. The tibial N. gave rise to the parafibular N. then divided to form the Nn. suralis medialis and lateralis. The N. suralis medialis continued as the N. metatarsalis plantaris medialis. The parafibular N. continued as the N. plantaris lateralis, which terminated as the R. digitalis of the fourth digit. The fibular N. terminated as the superficial and deep fibular N.s. The superficial fibular N. continued as the N. metatarsalis dorsalis lateralis and divided into two digital N.s to the third and fourth digits. The deep fibular N. crossed the ankle joint and continued as the N. metatarsalis dorsalis medialis that continued as the R. digitalis of the third digit. In general, the innervation of the pelvic limb of the ostrich was similar to the pelvic limbs of several different species of domesticated birds, including the chicken. We discuss the few differences as well as appropriate sites to perform nerve blocks for the lateral and medial dorsal and the lateral plantar N.s.