Abstract: A bone screw having a threaded proximal portion, a threaded median portion, and a threaded distal portion. The threaded proximal portion has a proximal thread with a constant diameter and a proximal pitch. The threaded median portion has a median thread with a constant diameter smaller than the diameter of the proximal thread and a median pitch that becomes increasingly smaller from a distal end of the threaded median portion towards a proximal end of the threaded median portion. The threaded distal portion has a distal thread having a constant diameter that is smaller than the diameter of the median thread and a distal pitch that is larger than the median pitch at the distal end of the threaded median portion.

Abstract: A bone screw having a threaded proximal portion, a threaded median portion, and a threaded distal portion. The threaded proximal portion has a proximal thread with a constant diameter and a proximal pitch. The threaded median portion has a median thread with a constant diameter smaller than the diameter of the proximal thread and a median pitch that becomes increasingly smaller from a distal end of the threaded median portion towards a proximal end of the threaded median portion The threaded distal portion has a distal thread having a constant diameter that is smaller than the diameter of the median thread and a distal pitch that is larger than the median pitch at the distal end of the threaded median portion.

Abstract: A bone screw (1) having a threaded proximal portion (2), a threaded median portion (3), and a threaded distal portion (4). Threaded proximal portion (2) has a core (11) with a constant diameter and a proximal thread (12) with a constant diameter and a proximal pitch (P2). The threaded median portion (3) has a core (15), which is conical, with a diameter becoming increasingly larger from the distal end of the threaded median portion (3) to the proximal end thereof, and thread (16), which has a constant diameter smaller than the diameter of the thread (12) of the proximal threaded portion (2). The pitch of thread (16) of the threaded median portion (3) becomes increasingly smaller from the distal end of the threaded median portion (3) towards its proximal end. At the proximal end of the threaded median portion (3), the pitch of thread (16) is larger than the pitch (P2) of the thread (12) of the threaded proximal portion (2).

Abstract: A bone screw (1) having a threaded proximal portion (2), a threaded median portion (3), and a threaded distal portion (4). Threaded proximal portion (2) has a core (11) with a constant diameter and a proximal thread (12) with a constant diameter and a proximal pitch (P2). The threaded median portion (3) has a core (15), which is conical, with a diameter becoming increasingly larger from the distal end of the threaded median portion (3) to the proximal end thereof, and thread (16), which has a constant diameter smaller than the diameter of the thread (12) of the proximal threaded portion (2). The pitch of thread (16) of the threaded median portion (3) becomes increasingly smaller from the distal end of the threaded median portion (3) towards its proximal end. At the proximal end of the threaded median portion (3), the pitch of thread (16) is larger than the pitch (P2) of the thread (12) of the threaded proximal portion (2).

Abstract: This surgical clip (1), comprises, on at least one lateral arm (3), several successive projecting portions (4), particularly of a tapered shape, forming series of shoulders (5) suitable for opposing, after insertion, the extraction of said lateral arm (3) from the bone. According to the invention, at least one projecting portion (4) of said lateral arm (3) comprises at least one groove (6) opening onto the shoulder (5) formed by said portion (4), said groove (6) and said shoulder (5) thus delimiting a pointed and sharp material zone (7), suitable for hollowing the bone when, after the intermediate arm (2) of the clip has been cut, said lateral arm (3) is driven in rotation.