Figs. 202 and 203. Areae of distribution of the Cutaneous Nerves 

 of the Lower Extremity. Right Side. 



Outlines partly after Fau's Atlas. Areae of Nerves are partly diagrauuitatic. 

 Colours are chosen in the order of segmentation : those for the Lumbar Plexus are 

 ill accord with the colours tised, in the two following figures, for the segments 



of the cord. 



The Cutaneous Nerves of the Lower Extremity require thorough re-investi- 

 gation, far more than those of the Upper Limb. The upper quarter of the thigh 

 is supplied by the following Cutaneo-sensory Nerves:— Outer third, Ilio-hypogastric 

 (red); Middle, Crural Branch of Genito-Crural; Inner third. Genital Branch of 

 Genito-Crural. These 2 areae, supplied by the same nerve, are yellow; only a 

 small area near the Scrotum (visible on separation of the thighs) is supplied b)^ 

 the Perineal Branch of the Small Sciatic. The remainder of the Anterior Surface 

 is supplied in its outer third, by the External Cutaneous, internal to this, by the 

 Middle and Internal Cutaneous; at its innermost part, by the Obturator Nerve. 



The two l^ateral Nerves extend on to the posterior aspect which is chiefly 

 supplied by the Small Sciatic Nerve. 



The Gracilis is not often perforated b}' the Cutaneous Branch of the 

 Obturator; this Nerve usualh' winds round the border of the Adductor Longus 

 Muscle and thus comes to the surface at the Anterior Border of the Gracilis. It 

 nearly alwaj's anastomoses with the Internal Cutaneous Nerve and comes to lie 

 near the Long Saphenous Nerve after piercing the fascia, so that this Nerve is 

 composed of fibres from the Internal Cutaneous as well as from the Obturator Nerve. 



The inner surface of the Leg is entirely supplied by the Terminal Sensor}' 

 Brjmches of the Anterior Crural Nerve, namel}', the Long Saphenous Nerve which 

 reaches down as far as the inner border of the foot, and so becomes the longest 

 nerve in the bod}'. All other parts of the Foot and Leg are supplied by the 

 Great Sciatic Nerve and its branches. 



In the Leg, the Internal and External Popliteal Nerves apportion the skin 

 between each other, the former taking the middle of the calf, the latter the outer side. 

 In the Foot, the Dorsum belongs to the External Popliteal, the Sole to the 

 Internal Popliteal. 



At the Heel, the Internal and External Calcanean Branches should be 

 mentioned. The area of the Internal Plantar corresponds to the distribution of the 

 Median, that of the External Plantar to the Ulnar in the hand. 



The supply of the Dorsum of the Foot exhibits no similarity to that of the 

 Hand. Besides the Superficial Nerves a Deep Branch from the Anterior Tibial 

 Nerve has to be considered in its supply to the contiguous margins of the Big 

 and 2nd Toes. 



