Case report

The proband was a male born by spontaneous vaginal delivery at term following an uneventful pregnancy. The parents are healthy, unrelated, and white. Birth weight was 4140 g (97th centile). Early childhood was complicated by hypotonia and recurrent sleep apnoea which resolved following adenoidectomy at 2 years of age. Otherwise, his medical history showed the normal range of intercurrent childhood viral illnesses. While childhood linear growth was rapid, during the second year there was considerable concern about poor weight gain. At 6 years of age he was noted to have a high, bossed forehead with a large head circumference (90-97th centile). A thoracolumbar kyphoscoliosis and a mild sternal depression was noted. He attended normal school although moderate learning difficulties were experienced. An attention deficit defect was identified and managed with the aid of methylphenidate hydrochloride. At 15 years of age, he was tall and thin (height 176 cm, 80th centile; weight 43.3 kg, 5th centile) with an associated moderate thoracolumbar kyphoscoliosis and pectus carinatum deformity. While the upper segment:lower segment ratio was 0.804, it was apparent that spinal height was somewhat reduced by the curvature of the scoliosis. The span measurement was 175 cm and head circumference was 56.0 cm (60th centile). He was a generally thinly muscled adolescent with little subcutaneous tissue. Some mild proximal upper limb weakness was detected and winging of the scapulae was evident, particularly on the right side. Examination of the musculature around the scapulae showed that the trapezius muscles were absent or possibly extremely hypoplastic. Ophthalmic examination showed normal fundi with no …