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thigh ; the skin of the anterior aspect of the thigh and of the antero- 

 median aspect of the leg; the femoral artery, the femur and the hip 

 and knee joints. 



The obturator nerve supplies the external obturator muscle, the 

 gracilis and the adductor muscles, a varying extent of skin on the 

 median aspect of the thigh, and branches to the hip and knee joints. 



Thus in the supply of the anterior aspect of the lower limb the 

 territory of the more lateral nerve, the femoral, much exceeds that 

 of the more median, the obturator. 



In addition to these two nerves an "accessory obturator" nerve 

 sometimes is found to arise from the XXIII or XXIV spinal (3. or 

 4. lumbar) nerves, course over the pubic crest and aid the obturator 

 nerve in its supply. 



The peroneal and tibial nerves most frequently arise from the 

 sacral plexus by common roots from the XXIV, XXV, XXVI, 

 XXVII and XXVIII spinal (4. and 5. lumbar, 1., 2. and 3. sacral) 

 nerves and pass down the posterior aspect of the thigh as a common 

 trunk, the sciatic nerve, which divides somewhere above the knee 

 joint into its constituent branches. The sciatic nerve can however 

 usually be readily divided artificially back to the spinal nerves. It 

 is then found that the source of supply of the peroneal nerve is less 

 extensive than that of the tibial nerve, the peroneal and tibial nerves 

 supply essentially the posterior aspect of the limb. 



The peroneal nerve and its branches, including the gluteal nerves, 

 supply the postero-lateral musculature of the hip, the thigh and the 

 leg, the dorsal musculature of the foot and the skin of the lateral 

 side of the leg and the dorsum of the foot. The tibial nerve and 

 its branches supply the postero-median musculature of the hip and 

 the thigh and the musculature of the posterior aspect of the leg and 

 the sole of the foot, together with the over-lying skin. Both nerves 

 furnish arterial and articular branches. The posterior nerves of the 

 lower limb extend further distally than the anterior nerves, encroach 

 more and more on the anterior aspect of the limb and at the foot 

 furnish the whole nerve supply. 



Paterson first called careful attention to the natural separation 

 of the main nerves springing from the lumbar and sacral plexuses 

 into dorsal and ventral groups, the femoral and peroneal nerves 

 belonging to the former, the obturator and tibial nerves to the latter. 

 Though in the plexus the nerves supplying the lateral aspect of the 

 limb have a dorsal position and those supplying the median aspect 

 of the limb a ventral position, it would probably be better to adopt 



