Compound fractures, being commonly associated with extravasation of urine, are liable to infective complications. Loose fragments should be removed, as they are prone to undergo necrosis.
The patient is confined to bed for six or eight weeks, and it may be several weeks more before he is able to resume active employment.
The acetabulum may be fractured by force transmitted through the femur, usually from a fall on the great trochanter, less frequently from a fall on the feet or other form of violence. It may merely be fissured, or the head of the femur may be forcibly driven through its floor into the pelvic cavity, either by fracturing the bone or, in young subjects, by bursting asunder the cartilaginous junction of the constituent bones. When the femoral head penetrates into the pelvis—the central dislocation of the hip of German writers—the condition simulates a fracture of the neck of the femur, but the trochanteric region is more depressed and the trochanter lies nearer the middle line. The limb is shortened, and movements of the joint are painful and restricted, especially medial rotation. In some cases there is pain along the course of the obturator nerve.
On rectal or vaginal examination there is localised tenderness over the pelvic aspect of the acetabulum, and in some cases a convex projection, or even crepitating fragments can be detected. The diagnosis is completed by an X-ray picture.
When the head of the femur penetrates the acetabulum, reduction should be attempted by traction and manipulation. The pelvis is held rigid, and the thigh is flexed and forcibly adducted, while the medial side of the thigh rests against a firm sand-bag; the femoral head is thus lifted out of the pelvis. In a recent injury the amount of force required is relatively slight. The head is kept in its corrected position by extension.
Fracture of the upper and back part of the rim of the acetabulum may accompany or simulate dorsal dislocation of the hip. Crepitus may be present in addition to the symptoms of dislocation, and after reduction the displacement is easily reproduced. The treatment is by extension with the limb adducted.
Fracture of Individual Bones of the Pelvis.—Ilium.—The expanded portion of the iliac bone is often broken by direct violence, the detached fragments varying greatly in size and position ([Fig. 56]).
The whole or part of the crest may be separated by similar forms of violence.
When the fracture implicates the ala of the bone, it usually starts at the triangular prominence near the middle of the crest, and runs backwards or forwards, passing for a variable distance into the iliac fossa. The displaced fragment can sometimes be palpated and made to move when the muscles attached to it are relaxed. This is done by flexing the thighs and bending the body forward and towards the affected side. Pain and crepitus may be elicited on making this examination.
These fractures are treated by applying a roller bandage or broad strips of adhesive plaster over the seat of fracture, and by placing the patient in such a position as will relax the muscles attached to the displaced fragment—in the case of the iliac spine by flexing the thigh upon the pelvis; in the case of the crest or ala by raising the shoulders. Union takes place in three or four weeks.