Abstract: A device is proposed comprising a main support structure (10) and associated bone pins (32-36), each pin having leading and trailing treads (36, 34) of the same hand and pitch but with the latter thread of larger diameter to engage any one of a plurality of like threaded bores (19) through the main structure. Preferably the main structure includes an elongate frame (11) of closed loop form with a separable end (15) and two slide plates (12) mounted therein in adjustable end-to-end relation, each plate having at least two bores in an overall array orthogonal of the plates and longitudinal of the frame. The device also preferably has a cap (37) to cover the exposed trailing ends of the pins. The device is particularly useful in dorsal application for finger bone fracture fixation.