Hip deformities

COXA VARA Coxa vara is a progressive disorder of the proximal end of the nur. At birth the femoral neck-shaft angle is approximately 175 degrees, and as the child ages this angle decreases to about 125 degrees. If this angle is less than 120 degrees, it is classified as coxa vara. The cause of coxa vara is unknown, but it is thought to be primarily an endochondral ossification defect in the femoral neck. 3 The incidence is low and appears to be equally distributed between the sexes.

Signs and Symptoms: Fig. l.a. Coxa vara condition illustratingFig. I.b. Abductor contracture resulting from Weight-bearing area of the hip to be moreCoxa vera. Superior and lateral. 66 The disorder is usually not recognized until the child begins > walk. A painless limp and appearance of a short limb often become obvious. Excessive lordosis, limited abduction, mild hip Qexion contracture, and limited hip extension may occur concomitantly (Fig. 1).

Fig. l.a. Coxa vara condition illustratingFig. I.b. Abductor contracture resulting from Weight-bearing area of the hip to be moreCoxavera.Superior and lateral.

Treatment: The goals for treatment are to increase the angle of inclination, promote ossification of me caxtila^mous femoral defect, and reorient the growth plate to a more horizontal position If the angle of inclination is greater than 110 degrees the condition is not treated, but carefully observed; a lift in the shcl and stretching of the hip adductor, and lateral rotator muscles may be needed. If the angle of inclination falls below 110 degrees, surgery is tl treatment of choice. A subtrochantric or intertrochanteric osteotomy with a screw and plate or bifurcated blade plate is used.

© After surgery a hip spica cast is applied for 6 to 8 weeks. After removal of the cast, active, and gentle range-of-motion exercise for the hips and knee is begun. Active side-lying hip abduction and standing hip hiking (Trendelenburg's) exercises can be started. When full range of motion is obtained, partial weight bearing,three point crutch walking is allowed. When the Trendelenburg sign is negative, gait may be progressed to full weight bearing.

If bifurcated blade plate is used with the osteotomy, spica cast i: not necessaiy because the blade is stable; and partial weight bearing with crutches can begin 4 to 5 days after surgery. This procedure heals in approximately 8 weeks. Active range-of- motion and strengthening exercises can begin at the discretion of the surgeon.

COXA VALGA If the neck-shaft angle is greater than 130 degrees, it is classified as coxa valga (Fig. o)v The coxa valga could be due to trauma, congenital, dislocation of the hip or due to spastic paralysis.

Signs and Symptoms: In case of moderate unilateral involvement a painless limp is >resent. A leg-length difference with longer leg on the involved side (Fig. 1). Adductor tightness with upward pelvic obliquity and akness of the abductors also on the affected side (Fig. 2). The altered pelvic mechanics may cause back pain or sacroiliac joint dysfunction.

Result of coax valga is relative lengthening of placing affected hip in adduction.

Fig. £. v Levgr arm for abductora Is shortsnad In coxa vatga and creates an unfavorable posi­tion for the abductors, which contributes to adduction of affected side. A, Normal. B, Shortened la­yer arm.

Treatment: Mild asymptomatic coxa valga is important to treat. Severe cases are treated with osteotomy to correct leg-length difference and to restore normal mechanics. Stretching exercises for the adductors on the involved side and strengthening for the abductors of the same side are essentials. Patients should be taught how to keep the pelvis level so as to eliminate the limp. The therapist must pay careful attention to the position of the feet, if not correct foot-drill exercise should be given to correct foot position. General leg exercises should also be practiced, but the patient should not do many exercises in standing at first.

Balance exercises and free exercises of all kinds should be given to improve posture. Complications such as back pain, and sacroiliac dysfunction must, of course, be treated.