Device and method for mounting an object on a bone

摘要

A device for removable attachment to a bone of a living patient, useful as a mounting support for a trackable part of a computerized surgical navigation system and a method for attaching an object removably to a bone of a living patient. A shaft having a self drilling, self-tapping screw tip can be inserted transversely of the bone and securely screwed into the cortex. A screw drives a sharp-edged sleeve along the shaft to engage the near cortex. A stepping mechanism allows incremental angular movement of a portion of an adjustment mechanism and indicates when the sleeve is securely engaged by resisting further tightening.

主权项

1. A device for mounting an object removably on a bone, comprising:
(a) a central shaft having a distal end portion; (b) a threaded tip included in said distal end portion; (c) a bone-engaging member disposed on and movable longitudinally along said central shaft, said bone-engaging member having a bone-gripping distal end; (d) wherein said bone-engaging member is a sleeve including a longitudinally-extending slot and wherein a slot-engaging member is perpendicular to said slot and is engaged in said slot; (e) an adjustment mechanism mounted on said central shaft and arranged to move said bone-engaging member controllably toward said distal end of said central shaft; (f) wherein said adjustment mechanism includes a rotatable member engaged with an external thread on said central shaft; (g) wherein said bone-engaging member and said rotatable member form a torque-indicating mechanism; (h) wherein said torque-indicating mechanism includes a stepping mechanism; (i) wherein said stepping mechanism includes each of said bone-engaging member and said rotatable member having complementary and rigidly interlocking teeth; and (j) wherein said rotatable member when rigidly locked forms a monolithic structure with said longitudinally-extending slot and said slot-engaging member to prevent said sleeve from rotating about said central shaft, locking the sleeve axially.