Abstract: A medical device for assessing and/or rehabilitating a human joint of an extremity includes a joint brace comprising a first support for coupling to an upper part of the extremity, a second support for coupling to a lower part of the extremity, and a rotatable joint connecting the first and second supports, and a mechanical device coupled to the first and second supports, the mechanical device configured for moving one or more of the first and second supports so as to rotate about the joint. In another alternative the medical device can include sensors located for making angle measurements between the first and second supports and for recording movement data and a computing device for receiving and storing the angle measurements and the movement data and for transmitting said data via a radio transmitter.