Congenital insensitivity to pain and anhidrosis.

Congenital insensitivity to pain and anhidrosis (CIPA) is a rare reported entity characterised by disturbance in the pain and temperature perception due to involvement of the autonomic and sensory nervous system. It is an autosomal recessive trait with several defects of the gene NTRK1 coding for the neurotrophic tyrosine kinase - a nerve growth factor receptor on chromosome 1q21-q22. Traumatic fractures are common and, because of lack of pain, may go unrecognised for prolonged periods, resulting in nonunion or pseudoarthrosis. A Charcot joint may be the end result. Treatment complications are very common in these patients and range from infection to wound breakdown to failure of fixation. We report here a rare case of CIPA in a 9-year-old girl and her younger male sibling with generalised absence of pain, anhidrosis and its orthopaedic implications.