Developmental * primary defect in endochondral ossification of the medial part of the femoral neck (Most common cause) * Excessive interuterine pressure on the developing fetal hip * vascular insult * Faulty maturation of the cartilage and metaphyseal bone of the femoral neck Clinical feature: presents after the child has started walking but before six years of age. Usually associated with a painless hip due to mild abductor weakness and mild limb length discrepancy. If there is a bilateral involvement the child might have a waddling gait or trendelenburg gait with an increased lumbar lordosis. The greater trochanter is usually prominent on palpation and is more proximal. Restricted abduction and internal rotation. X-ray: decreased neck shaft angle, increased cervicofemoral angle, vertical physis, shortened femoral neck decrease in femoral anteversion. HE angle (Hilgenriener epiphyseal angle- angle subtended between a horizontal line connecting the triradiate cartilage and the epiphysis); normal angle is <30 degrees. Treatment: HE angle of 45–60 degrees: observation and periodic follow up. Indication for surgery: HE angle more than 60 degrees, progressive deformity, neckshaft angle <90 degrees, development of Trendelenburg gait Surgery: subtrochanteric valgus osteotomy with adequate internal rotation of distal fragment to correct anteversion; common complication is recurrence. If HE angle is reduced to 38 degrees, less evidence of recurrence; post operative spica cast is used for a period of 6–8 weeks.<unk>  is also seen in Niemann–Pick disease. Congenital Presence at birth is extremely rare and associated with other congenital anomalies such as proximal femoral focal deficiency, fibular hemimelia or anomalies in other part of the body such as cleidocranial dyastosis. The femoral deformity is present in the subtrochanteric area where the bone is bent. The cortices are thickened and may be associated with overlying skin dimples. External rotation of the femur with valgus deformity of knee may be noted. This condition does not resolve and requires surgical management. Surgical management includes valgus osteotomy to improve hip biomechanics and length and rotational osteotomy to correct retroversion and lengthening.
Coxa vara
Coxa valga
Boswellia
Haemophilus ducreyi
Brugia timori
Monilethrix
Toxoplasma gondii
Herpes gladiatorum