OBTUEATOE NEEVE. 



723 



1. An articular branch to the hip-joint, which arises from the nerve as soon as 

 it enters the thigh, and supplies the joint through the acetabular notch. 



2. Muscular branches to the adductor longus, gracilis, adductor brevis (usually), 

 pectineus (occasionally). The last-named muscle is not usually supplied from the 

 obturator nerve. 



3. A cutaneous branch of very variable size forms one of the terminal branches 

 (Fig. 626). It becomes superficial between the gracilis and adductor longus, in the 

 middle third of the thigh, and may supply the skin of the distal two- thirds of the 

 thigh on its medial side. It is generally of small size, and is connected with 

 branches of the medial cutaneous and saphenous nerves behind the sartorius muscle 

 to form the obturator (O.T. sub -sartorial) plexus. The branch from the saphenous 

 nerve to the plexus passes medially behind the sartorius after piercing the 



Obturator nerve 



Os pubis 

 Cut edge of psoas major 



Nerve to pectineus 

 Posterior ramus of obturator nerv 

 Anterior ramus of obturator nerve 

 Descending muscular branches 



Pectineus -~ 



Ascending branch to 

 obturator externus 



Medial circumflex artery 



Adductor longus- 

 Adductor brevis 



Cutaneous branch 



Second sacral vertebra 

 Piriformis 



Glutseus maximus 



Peritoneum 

 Obturator interims 

 Obturator externus 



Ramus of ischium 



Ascending branch of medial 

 circumflex artery 



Quadratus femoris 

 Medial circumflex artery 



Descending muscular branch 

 Adductor magnus 



Branch to knee-joint 



Branch to femoral artery Gracilis 



FIG. 626. SCHEME OP THE COURSE AND DISTRIBUTION OF THE OBTURATOR NERVE. 



aponeurotic covering of the adductor canal. The branch from the medial cutaneous 

 nerve is generally superficial at the point of formation of the plexus. 



4. The branch to the femoral artery is the other terminal branch of the 

 nerve. It enters the adductor canal along the medial border of the adductor 

 longus, and ramifies over the distal part of the artery. 



5. A fine communicating branch sometimes joins the femoral nerve in front 

 of the hip-joint. 



The posterior (O.T. deep) branch of the obturator nerve reaches the thigh 

 by piercing the obturator externus muscle. It passes distally between the adductor 

 brevis and adductor magnus muscles. After passing obliquely through the 

 adductor magnus, it appears in the popliteal fossa on the popliteal vessels, and 

 terminates by piercing the oblique ligament of the knee and supplying the knee- 

 joint. 



Its branches are : (1) muscular branches to the obturator externus, adductor 

 magnus, and (when the muscle is not supplied by the superficial part of the nerve) 



