A 9.5-year-old boy was referred to the neurology clinic for waddling gait and hip pain. He has had a history of constipation, cold intolerance, reduced energy, and poor concentration for at least 4 years. In addition, he has mild developmental delay but is able to cope in normal mainstream school.
On physical examination, he had rounded facies, dry skin, loss of the lateral third of his eyebrows, coarse hair, low-pitched voice, macro-orchidism, and a waddling gait. He did not have goiter, proximal myopathy, or a delayed relaxation phase of deep tendon reflexes. He was extremely short for his age. His height of 108.8 cm (SD score, −4.54) was also significantly lower than his parental target centile range of 151 cm (SD score, −3.53) to 171 cm (SD score, −0.79). His bone age was delayed at 2 years. Radiographs of the left hip (Figure 1) and the hand, lower limbs, spine, and skull (Figure 2) were obtained.