Page 1 of 1: ORTHO

thakral_anuj · Credits: 451 My Scrapbook

14.VASCULAR SIGN OF NARATH SEEN IN
a.IT# femur
b.ant.dislocation femoral head
c.post.dislocation femoral head[/code]

drpsg · Credits: 6178 My Scrapbook

POSTERIOR DISLOCATION

Machanism

Posterior dislocation is the commonest type of dislocation. It is caused by violence applied along the femoral shaft when the hip joint is in a flexed and adducted position. It occurs in an automobile accident when the passenger sitting by the driver is thrown forward, his knee hitting against the dashboard.

Clinical features

A young adult is brought with a history of severe injury to the hip and inabilty to stand or walk. On examination, the limb is seen to lie in the characteristic position of adduction, flexion and internal rotation with marked shortening. The pulsation of the femoral artery at the mid-inguinal point is not palpable due to the absence of the femoral head in the normal position (Vascular sign of Narath). The greater torchanter is raised and the head of the femur could be felt posteriorly under the gluteal muscles. All movements of the hip or extermely painful. One must look for the presence of the sciatic nerve paralysis causing foot drop, as a complication.

Radiological features

A.P. view of pelvis to show both hips will show the head lying outside and above the acetabulum. The Shenton's line will show a break in continuity. Shenton's line in the radiograph is normally a continous line running along the inferior margin of the femoral neck and the upper margin of the obturator foramen. Occasionally, there may be a complicating fracture of the postero superior margin of the acetabulum.

Treatment

The dislocation is reduced by manipulation under general Anaesthesia .

Technique

The Anaesthesia should be deep to relax all the powerful muscles. The patient is put on a mattress on the floor and the surgeon stands gripping the patients leg by knee and ankle and bending over the patient. While an assistant kneels by the side of the patient and fixes the pelvis with both his hands, steady traction is applied to relax the muscles; the leg is then circumducted through external rotation, abduction and extension. The hip will be felt to reduce with an audible click. This is called the Bigelow's technique.

Another technique of reduction is to flex the hip and knee to 90 degree and apply steady forward traction. The head slips forward into position.

After reduction, the keg can be placed in normal position and the length will be found to be equal. A firm elastocrepe spica bandage is applied to the hip and the leg is immobilised in a Thomas splint. A check radiograph is taken. It is very important to continue immobilisation for 3-4 weeks to allow for the sound healing of the ruptured capsule, ligaments and other soft tissues. Patient is allowed full weight bearing in six weeks.

A large acetabular fragment, if present, will need open reduction and internal fixation with a screw.

Complications

Immediate:

i. Associated fracture acetabular rim
ii. Sciatic nerve palsy

Late:

i. Avascular necrosis of head of femur
ii. Myosiitis ossificans.

DRATKINS · Credits: 8535 My Scrapbook

gud job, Drpsg

drpsg · Credits: 6178 My Scrapbook

welcome any time dratkins

		Sign In New User? Sign Up Sign in to access your control panel and messenger!
				TechZone \| SpiderNevi \| HowTo? \| Scrapbook!