Anti-unscrewing and multi-angular fastening apparatuses and methods for surgical bone screw/plate systems

A surgical anti-unscrewing system that provides anti-unscrewing features, comprising:

• (a) a fastener comprising an elongate section and an adjoining head section disposed along a fastener axis, the head section comprising a thread and an at least one slot defined in an outer periphery of the head section that extends therewithin;
• (b) a fastener receiving member comprising first and second opposing major surfaces, an inside surface extending between the first and second major surfaces and defining an aperture generally coaxially disposed about an aperture axis, and a tappable contact region comprising protrusions disposed on the inside surface, wherein the protrusions project into the at least one slot of the fastener, thereby preventing the fastener from backing out of the fastener receiving member;
• and
• (c) a fastener driver providing torsional force to the fastener and comprising first and second ends, wherein the first end comprises at least one slot engagement portion matingly receivable by the at least one slot of the fastener, whereby during insertion of the fastener by the fastener driver the at least one slot engagement portion prevents the protrusions from projecting into the at least one slot to facilitate insertion and during removal of the fastener the slot engagement portion deflects the protrusions out of the at least one slot to facilitate removal.

A surgical method for affixing a fastener to a fastener receiving member such that the fastener will not back-out of the fastener receiving member, comprising:

• (a) providing a fastener comprising an elongate section and an adjoining head section disposed along a fastener axis, the head section comprising a thread and at least one slot defined in an outer periphery of the fastener and that extends therewithin;
• (b) providing a fastener receiving member comprising first and second opposing major surfaces, an inside surface extending between the first and second major surfaces and defining an aperture generally coaxially disposed about an aperture axis, and a tappable contact region disposed on the inside surface;
• (c) selecting an insertion angle at which the fastener is to be inserted in relation to the fastener receiving member, wherein the insertion angle is defined between the fastener axis and the aperture axis;
• (d) inserting the elongate section of the fastener through the aperture until the thread of the head section contacts the tappable contact region;
• and
• (e) tapping the fastener into the fastener receiving member such that the fastener is oriented at the selected insertion angle by threading the thread of the head section into the tappable contact region while the fastener is oriented at the selected insertion angle, and wherein the tappable contact region engages the at least one slot after insertion to prevent backing out of the fastener by a portion of the tappable contact region extending into the slot of the fastener.

A surgical fastening apparatus adapted to provide anti-unscrewing features, comprising:

• (a) a fastener comprising an elongate section with an external thread and an adjoining head section disposed along a fastener axis, the head section comprising a thread and at least one slot defined in an outer periphery of the head section that extends therewithin;
• and
• (b) a fastener receiving member comprising first and second opposing major surfaces, an inside surface extending between the first and second major surfaces and defining an aperture generally coaxially disposed about an aperture axis, and a tappable contact region disposed on the inside surface;
• (c) wherein the tappable contact region is formed so as to allow for being tapped by the external thread of the elongate section of the fastener to affix the fastener to the tappable contact region at a selected one of a plurality of different insertion angles that can be selectively formed between the fastener axis and the aperture axis;
• and
• (d) wherein the tappable contact region comprises a plurality of protrusions extendable into the slot of the fastener to prevent backing out of the fastener and the tappable contact region is deflectable from the slot of the fastener to permit removal of the fastener.