Patient movement sensor

Abstract

A motion sensor for detecting the movement of a patient is provided and includes a housing, a spring loaded return mechanism supported in the housing, an encoder, and a sensor. The spring loaded return mechanism includes a spool rotatably supported within the housing, a biasing member coupled to the housing and the spool, and a cord supported on the spool. The encoder is located on the spool and is configured to monitor a length of cord extended from the housing. The sensor is configured to communicate a signal when the cord is extended beyond a predetermined or preset length.

1 . (canceled) 
     
     
         2 . A method of monitoring movement of a patient on a surgical table, the method comprising:
 utilizing a motion sensor assembly including an encoder, and a gyroscope disposed in mechanical cooperation with the encoder;   measuring an angle of a longitudinal axis of the patient using the gyroscope; and   comparing the angle of the longitudinal axis of the patient with a preset longitudinal axis.   
     
     
         3 . The method according to  claim 2 , wherein the motion sensor assembly includes a cord extending between a housing of motion sensor assembly and the patient, and further comprising determining whether the cord is extended beyond a predetermined length using a sensor. 
     
     
         4 . The method according to  claim 3 , further comprising sending a signal when the sensor determines the cord is extended beyond the predetermined length. 
     
     
         5 . The method according to  claim 3 , wherein determining the length of the cord extending between the housing and the patient is accomplished using the encoder. 
     
     
         6 . The method according to clam  5 , wherein the cord is engaged with a spool of the motion sensor assembly. 
     
     
         7 . The method according to  claim 6 , wherein the encoder is located on the spool. 
     
     
         8 . The method according to  claim 7 , further comprising converting an angular position of the spool into data using the encoder, and processing the data into a distance travelled by the cord. 
     
     
         9 . The method according to  claim 2 , further comprising monitoring a position of the patient on the surgical table with respect to the motion sensor assembly. 
     
     
         10 . The method according to  claim 2 , further comprising defining a tissue access point on the patient for a surgical instrument. 
     
     
         11 . The method according to  claim 10 , further comprising monitoring a position of the patient on the surgical table with respect to the motion sensor assembly including resetting the tissue access point on the patient and defining a new tissue access point on the patient for the surgical instrument in response to movement of the patient. 
     
     
         12 . The method according to  claim 2 , further comprising monitoring the position of the patient on the surgical table with respect to the motion sensor assembly including stopping a surgical procedure when the patient has moved beyond a predetermined limit. 
     
     
         13 . The method according to  claim 2 , further comprising monitoring the position of the patient on the surgical table with respect to the motion sensor assembly including stopping a surgical procedure when the angle of the longitudinal axis of the patient is beyond the preset longitudinal axis. 
     
     
         14 . A method of determining movement of a patient on a surgical table, the method comprising:
 utilizing a motion sensor assembly including a housing and a gyroscope disposed in mechanical cooperation with the housing;   measuring an angle of a longitudinal axis of the patient relative to a preset longitudinal axis using the gyroscope; and   monitoring the position of the patient on the surgical table with respect to the motion sensor assembly.   
     
     
         15 . The method according to  claim 14 , further comprising stopping a surgical procedure when the angle of the longitudinal axis of the patient is beyond the preset longitudinal axis. 
     
     
         16 . The method according to  claim 14 , further comprising sending a signal when a sensor of the motion sensor assembly determines that the angle of the longitudinal axis of the patient is beyond the preset longitudinal axis. 
     
     
         17 . The method according to  claim 14 , further comprising comparing the longitudinal axis of the patient to a predetermined incline angle of the surgical table. 
     
     
         18 . The method according to  claim 14 , wherein monitoring the position of the patient on the surgical table includes monitoring an angular position of the patient on the surgical table. 
     
     
         19 . The method according to  claim 14 , further comprising defining a tissue access point on the patient for a surgical instrument. 
     
     
         20 . The method according to  claim 19 , further comprising resetting the tissue access point on the patient and defining a new tissue access point on the patient for the surgical instrument. 
     
     
         21 . A method of monitoring movement of a patient on a surgical table, the method comprising:
 utilizing a housing, a gyroscope disposed in mechanical cooperation with the housing, and a cord extending between the housing and the patient;   measuring an angle of a longitudinal axis of the patient using the gyroscope; and   comparing the angle of the longitudinal axis of the patient with a preset longitudinal axis.