REGION OF THE HIP. 



pus forms it first perforates the articular cartilage and enters the joint and then 

 perforates the capsule to point externally. There are three favorite places of exit, 

 viz. : ( i ) on the posterior surface of the neck between the branches of the ischio- 

 femoral ligament; (2) on the lower anterior surface beneath the iliopsoas tendon, be- 

 tween the pubofemoral and iliofemoral ligaments, through the bursa found here 

 which may communicate with the joint ; and (3) at the cotyloid notch. 



The head and neck of the femur and also the acetabulum become carious. Pus 

 may find an exit at other places besides those mentioned. It may perforate the ace- 

 tabulum and show above Poupart's ligament at its outer side, or may break through 

 the upper posterior portion of the capsule. Not often does it break through between 

 the branches of the iliofemoral ligament. When it does break through anteriorly it 

 points in Scarpa's triangle, commonly to the in- 

 side of the vessels; when it breaks through pos- _------. 



teriorly it descends beneath the fascia lata and 

 points on the posterior or outer portion of the 

 thigh. 



Coxa Vara. The normal angle which the 

 head and neck make with the femoral shaft may 

 vary according to Humphry (Jour. Anat. and 

 Phys. , xxiii, 236) from 1 10 to 140 degrees. Some- 

 times as a result of injury or disease the neck 

 makes a more acute angle than normal, coming 

 off at an angle of 90 degrees or less. This is 

 called coxa vara (Fig. 526). In some cases it is 

 due to a bending of the neck caused by soften- 

 ing of the bone, as in rachitic affections, or to 

 fracture. The limb is shortened, the trochanter 

 raised above the Roser-Nelaton line, and abduc- 

 tion and flexion are restricted. To rectify it 

 Whitman's operation of wedge-shaped resection 

 is done. A wedge of bone with a base of 2 cm. 

 (^ in.), apex inward, is removed at a point op- 

 posite the lesser trochanter. The femur is then 

 placed in abduction and the bone allowed to heal. 

 When the limb is brought down the angle of the 

 head and neck will be much increased and the 

 deformity and disability will have been removed. 



Coxa Valga. The term coxa valga has 

 been applied to the opposite condition, when the 



neck is nearly parallel with the shaft ; it is rarer and of less importance than is coxa 

 vara. Orthopaedists regard 135 degrees as the normal limit of the angle between the 

 neck and shaft of the femur, but Humphry placed it at 140 degrees. 



FIG. 526. Normal angle of the head and 

 neck to the shaft of the femur with the altera- 

 tion in position in coxa valga and coxa vara 

 shown by dotted lines. 



OPERATIONS ON THE HIP-JOINT. 



The operations on the hip are usually done either for hip-disease or congenital 

 luxations. More rarely traumatic or pathological luxations or intracapsular fractures 

 may be operated on. The joint may be approached either anteriorly or laterally. 

 Lateral operations are the more mutilating, while anterior ones are often sufficient 

 and less serious. 



Lateral Operations. In approaching the joint from the side the incision of 

 Langenbeck is preferred. It begins well up on the buttocks on a line with the pos- 

 terior superior spine (page 500) and is continued down over the great trochanter in 

 the axis of the thigh. If made with the limb flexed the line of incision will be 

 straight. The muscular fibres and tendon of the gluteus maximus are cut in the line 

 of the incision. This exposes the posterior edge of the gluteus medius, which is to 

 be pulled forward, and the pyriformis, which is to be drawn backward or loosened 

 from its insertion into the trochanter. The capsule can then be incised and the joint 

 examined. Further exposure may be obtained by loosening the gluteus medius and 



