Patent ID: 8540724

Claim:
An apparatus for distracting two distractable elements and inserting an implantable element therebetween, the apparatus comprising: an elongate handle; first and second blades, the first and second blades having respective proximal ends that are connected to a distal end of the elongate handle, the first and second blades having respective distal ends configured to distract the two distractable elements; at least one stop member coupled to an outer face of at least one of the first and second blades; a longitudinally moveable drive shaft disposed through a passage formed by the elongate handle; a head block assembly mounted on a distal end of the drive shaft and disposed within a space formed between the first and second blades, the head block assembly including: a tip residing in a space defined by the first and second blades configured to push the implantable element to a selected depth between the distracted two distractable elements; first and second retraction members slidably disposed within respective first and second channels of the first and second blades, the first and second retraction members configured to maintain a constant height from the first and second blades, wherein the first and second retraction members are configured to engage respective outer faces of the distracted two distractable elements; and means for linearly adjusting a distance between the tip and the first and second retraction members to thereby linearly adjust a countersink depth of the implantable element between the distracted two distractable elements; wherein the means for linearly adjusting the distance between the tip and the retraction members comprises: a countersink member carriage having a first passage disposed therethrough along a longitudinal axis; a countersink member moveably coupled to the countersink member carriage the countersink member having a distal end comprising the tip; a thumbwheel having a second passage disposed therethrough along the longitudinal axis, the second passage having a threaded surface; and a countersink adjustment shaft disposed along the longitudinal axis and extending through the first passage and the second passage, the countersink adjustment shaft having a distal end coupled to the countersink member and a proximal end that is threaded; wherein threads of the second passage engage with threads of the countersink adjustment shaft, and wherein rotation of the thumbwheel causes longitudinal movement of the countersink adjustment shaft, and wherein longitudinal movement of the countersink adjustment shaft causes corresponding movement of the countersink member.