Optical Detection Method and Device for Optical Detection of the Condition of Joints

Abstract

An optical detection method and device are provided, wherein a body part comprising at least one joint is irradiated with light. Local attenuation of the light by the body part is detected as attenuation measurements at the position of the at least one joint and at the position of at least one other portion of the body part; and wherein blood flow to and/or from the body part is temporarily at least partially blocked and thereafter enabled again. Distinct local attenuation measurements for the at least one joint and for at least one other portion of the body part are performed for at least two of the times before (I), during (II), and after (III) the blocking of blood flow.

1 . Device for optical detection of the condition of joints, the device comprising:
 a measurement unit comprising a light source unit having at least one light source configured to irradiate a body part comprising at least one joint with light and a light detection element for locally and simultaneously detect attenuation of the light at the at least one joint and at least one other portion of the body part wherein the at least one other portion of the body part is a reference position which is not a joint;   a blood flow blocking unit provided with a pressure cuff for reducing the blood flow to and/or from the body part;   and a control unit configured to control the device such that:
 blood flow to and/or from the body part is reduced and thereafter restored again by the blood flow blocking unit; and 
 distinct local attenuation measurements for the at least one joint and for the at least one other portion of the body part are simultaneously performed at least two of: before the reducing of blood flow (I), during the reducing of blood flow (II), and after the reducing of blood flow (III); and 
   the control unit is further configured to compare the results of the distinct local attenuation measurements for the at least one joint and for the at least one other portion of the body part to each other.   
     
     
         2 . Device for optical detection of the condition of joints according to  claim 1 , wherein the blood flow blocking unit is adapted to reduce the blood flow by application of pressure. 
     
     
         3 . Device for optical detection of the condition of joints according to  claim 1 , wherein the light source unit is configured to emit light of at least two distinct wavelengths. 
     
     
         4 . Device for optical detection of the condition of joints according to  claim 3 , wherein the light source unit comprises at least two lasers. 
     
     
         5 . The device of  claim 3 , wherein one of the at least two different wavelengths has a higher absorption of light by a blood than another of the at least two different wavelengths. 
     
     
         6 . The device of  claim 1 , wherein the light source unit is configured to emit light of a wavelength between 550 and 980 nm. 
     
     
         7 . The device of  claim 1 , wherein the light source unit is configured to emit light of a wavelength between 600 nm and 805 nm. 
     
     
         8 . The device of  claim 1 , wherein the light source unit is configured to emit light in a red to near infrared wavelength. 
     
     
         9 . The device of  claim 1 , wherein the measurement unit comprises:
 a first optical component which directs the light from the light source to the body part; and   a second optical component which collects the light emerging from the body part and directs the collected light to the detection element and is configured to operate such that distinct local attenuation measurements for at least two different portions of the body part are performed.