The invention relates to a locking intramedullary nail (1) for insertion in the medullary cavity of hollow bones (2) for treating bone fractures or for joint stiffening, comprising an oblong shaft (5) having at least one holder (8) for a locking screw (3). In the region of an opening (8), a roller or ball-shaped sleeve (6) having a bore (4) for receiving the locking screw (3) is arranged. Said sleeve (6), which is supported in the shaft (5) in a freely pivotable manner preferably in all spatial axes in a defined angular region, can be locked in a positionally stable manner in the shaft (5). The substantial advantage is the possibility to introduce the locking screws (3) during the implantation of the intramedullary nail (1) at an optimum angle for the respective anatomical or pathological situation of the patient and to subsequently lock it permanently at a constant angle. Furthermore, a device (21-29) for facilitating the locking of the intramedullary nail (1) is provided.
