Objective To investigate the use of far infrared thermal imaging technology in diagnosing pain location for patients with chronic ankle arthritis.Methods Thirty-six patients with chronic ankle arthritis who were treated at a Chongqing hospital from March to November

2016 were included as the study group;meanwhile

32 healthy volunteers were recruited as the control group.A medical short-focus non-refrigeration far infrared thermal imaging system was used to measure the temperature at the anterior

posterior

medial and lateral points of bilateral ankle joints.The temperature values were compared between the left and the right ankle joints in the control group

or between the affected and the healthy ankle joints in the study group;comparison of the study group versus the control group was also performed.Results No significant differences were observed at all the measured points between the left and the right ankle joints in the control group（t=0.68

0.75

0.51

0.43;P>0.05）.In the study group

the temperature values at the anterior and lateral points of the affected ankle joint were significantly different from those of the healthy ankle joint（t=5.81

4.73;P<0.05）;while the temperatures at the posterior and medial points were similar between the affected and the healthy ankle joints（t=1.61

1.57;P>0.05）.The far infrared thermal imaging results of the anterior and lateral points of the affected ankle joint in the study group were positive.The bilateral temperature differences at the anterior and lateral points in the study group were significantly different from those in the control group（t=4.71

4.13;P<0.05）;while the temperature differences at the posterior and medial points were comparable between the two groups（t=1.25

1.63;P>0.05）.Conclusion Far infrared thermal imaging technology may describe the temperature distribution and changes at all points of the ankle joint

which allows for accurate localization of the ankle pain in patients with chronic ankle arthritis

and thus provides objective evidence for clinical management.