494 SURGICAL APPLIED ANATOMY. [Chap. xxm. 



fractures of the pelvis, by tumours of the pelvis, by 

 psoas abscess, by fractures and dislocations of the 

 femur, and by stabs in the region of the groin. In 

 this nerve lesion the patient is unable to flex the hip 

 and to raise the body from the recumbent position 

 (ilio-psoas). The power of extending the leg at the 

 knee is lost (quadriceps extensor cruris") ; the function 



Fig. 60. Amputation of Great Toe, with its Metatarsal Bone ^Agatz). 



a, Internal cuneiform bone ; ft, adductor polliois; c, extensor longus pollicis: 

 d, flexor longus pollicis ; e, plantar branch of dorsalis pedis artery. 



of the sartorius is destroyed and that of the pectineus 

 impaired. Sensation is impaired in parts supplied by 

 the internal and middle cutaneous nerves and the 

 long saphenous nerve. 



Paralysis of the obturator nerve alone is a 

 rare condition, although it may be found associated 

 with a like lesion of the preceding trunk. It may be 

 brought about by the pressure exercised upon the 

 nerve in cases of obturator hernia and by the foetal 

 head during delivery. The muscles implicated are the 

 adductors, the gracilis, pectineus, and external ob- 

 turator. The patient is unable to press the knees 

 together, or to cross the legs. Rotation outwards of 

 the thigh is difficult, and sensation is affected in the 



