Myopathy limited to the quadriceps and gastrocnemius muscles occurring in three brothers

This is a report of three cases of myopathy limited to the quadriceps and gastrocnemius muscles, occurring in the male offspring of the same mother but two different fathers. They have many similarities to a previously described clinical syndrome called quadriceps-confined myopathy. The pedigree demonstrates an apparent sex-linked recessive condition which has not been demonstrated previously. Information gained from a review of the literature is related to these three cases. It is suggested that these cases are part of a poorly defined clinical entity and that a new classification of quadriceps-gastrocnemius muscular dystrophy be introduced.