Gravity Dependent Pedicle Screw Tap Hole Guide and Data Processing Device

Abstract

A gravity dependent pedicle screw tap hole guide comprises a guide shaft maintainable parallel to a drill bit during the drilling of a pedicle screw tap hole; an accelerometer associated with a reference direction and responsive to gravity to determine an angular difference between an acting direction of gravity and the reference direction; and a mounting attaching the accelerometer to the shaft and establishing a positional relationship between the reference direction and the longitudinal axis. The accelerometer is preferably in communication with a data processing device or system, which data processing device is able to use signals from the accelerometer to perform one or more actions, such as, for example, displaying the angular difference.

1 . A system for forming a hole in a pedicle, comprising:
 an elongated element configured for partial advancement into a pedicle and having a proximal end, a distal end, and a longitudinal axis; and   a sensor fixed in a positional relationship relative to the longitudinal axis of the elongated instrument, the sensor being responsive to gravity to determine an angular difference between the longitudinal axis of the elongated instrument and an acting direction of gravity.   
   
   
       2 . The system of  claim 1 , wherein the elongated element is fixed to the sensor such that the longitudinal axis of the elongated element is parallel to a reference direction recognized by the sensor. 
   
   
       3 . The system of  claim 1 , further comprising an indicator for communicating to a user said angular difference. 
   
   
       4 . The system of  claim 3 , wherein the indicator is a visual indicator. 
   
   
       5 . The system of  claim 4 , wherein the visual indicator displays numerical values related to said angular difference. 
   
   
       6 . The system of  claim 5 , wherein the numerical values represent the angular difference between the longitudinal axis of the elongated element and the acting direction of gravity in degrees of angulation. 
   
   
       7 . The system of  claim 6 , wherein the display indicates a first degree of angulation relative to a first direction of movement and a second degree of angulation relative to a second direction of movement. 
   
   
       8 . The system of  claim 7 , wherein one of said first and second directions of movement is cranial-caudal and the other direction of movement is medial-lateral. 
   
   
       9 . The system of  claim 1 , further comprising a data processing device in communication with the sensor. 
   
   
       10 . The system of  claim 9 , wherein the data processing device receives signals from the sensor, interprets the signals, determines data from the signals, and at least one of presents the data and directs a second device using the data. 
   
   
       11 . The gravity dependent pedicle screw tap hole guide of  claim 10 , wherein the data represents the angular difference between the longitudinal axis of the elongated element and the acting direction of gravity. 
   
   
       12 . The system of  claim 9 , wherein the data processing device uses signals received from the sensor to perform an action. 
   
   
       13 . The system of  claim 9 , wherein the sensor uses signals received from the data processing system to perform an action. 
   
   
       14 . The system of  claim 1 , wherein said sensor is an accelerometer. 
   
   
       15 . An alignment guide for directing the positioning of a surgical implant, comprising:
 an elongate shaft having a proximal end and a distal end, said distal end being advancable through a patient to a surgical target site; and   a sensor fixed in a positional relationship with said elongate shaft, said sensor being operable to determine an angular orientation of said elongate shaft when said shaft is positioned at said surgical target site.   
   
   
       16 . The alignment guide of  claim 15 , wherein said sensor is permanently fixed to said elongate shaft. 
   
   
       17 . The alignment guide of  claim 15 , wherein said sensor communicates with a display to present said angular orientation to a user. 
   
   
       18 . The alignment guide of  claim 17 , wherein said display is integral to said alignment guide. 
   
   
       19 . The alignment guide of  claim 18 , wherein said display is an external display linked to said alignment guide. 
   
   
       20 . The alignment guide of  claim 19 , wherein said external display is part of a data processing device. 
   
   
       21 . The alignment guide of  claim 15 , wherein said sensor is an accelerometer.