Basanti a 7 year old girl, presents with bowing of legs and difficulty in walking. Her height was below average for her age group. Her one of the sibling also faces the same problems. On X-ray examination there is metaphyseal widening and funnel-like beaking of the metaphyses. Investigations showed a serum calcium of 9 mg/dl, serum phosphorus of 2.5mg/dl. The possible cause is:
Hypophosphatemic rickets (vitamin D-resistant rickets) is an dominant X-linked condition in which vitamin D production and metabolism are normal but renal tubular loss of phosphate interferes with skeletal ossification. The major manifestations are a mild-to-moderate decrease in stature and bowing of the lower extremities. The medical history usually discloses a parent or sibling with sho stature and bowlegs. In addition, serum phosphorus is reduced, and serum calcium is normal. Radiographic examination discloses characteristic widening of growth plates, funnel-like beaking of the metaphyses, and curvature of the femoral and tibial shafts, which are normally straight. Ref: Rab G.T. (2006). Chapter 11. Pediatric Ohopedic Surgery. In H.B. Skinner (Ed), CURRENT Diagnosis & Treatment in Ohopedics, 4e.
Nutritional rickets
Hypophosphatemic rickets
Azotemic renal dystrophy
Primary hyperparathyroidism