Isolated compression of the motor branch of the median nerve by a ganglion. Case report.

A 25-year-old hairdresser presented with a fluctuant lump in the palm of her right hand that was intermittently painful and made control of her right thumb difficult. She had no sensory loss. At operation a cystic swelling was found 8 mm in diameter distal to the carpal ligament and compressing the median nerve. The cyst ruptured during dissection, and it was not possible to localise the pedicle. Histological examination showed that it was a ganglion, and nine weeks after the operation the patient had regained normal use of her hand and resumed her work.