A mains electricity (AC-powered) device intended to provide continuous passive motion (CPM) exercise therapy for the hip and/or knee, typically following joint surgery/trauma to promote healing; some types may also operate with patient assistance under controlled active motion (CAM). The device may stimulate articular tissues, circulation of synovial fluid, reduce joint oedema, and provide neuromuscular and coordination training. It typically consists of a motorized carriage with straps to hold and move the leg/knee, and an electrical control unit for the healthcare professional to set the motion range/speed; digital displays and manual/automated safety capabilities may also be included.