The smartphone scoliosis screening software for measuring the Cobb angle of adolescent idiopathic scoliosis: a reliability study

Objective

To investigate the accuracy and repeatability of the software that we developed in measuring the adolescent idiopathic scoliosis (AIS) Cobb angle.

Methods

Fifty patients with AIS were included in the study. Three independent surveyors measured the Cobb angle of coronal main curve, thoracic kyphosis angle (TK), thoracolumbar kyphosis angle (TLK) and lumbar kyphosis angle (LL) by using protractor, scoliosis screening software and picture archiving and communication system (PACS). The measurement was repeated after an interval of 2 weeks. The measurement time of software method and protractor method were compared by Paired t-test. Taking the Cobb angle measurement results of the PACS as the reference standard. The repeatability of the surveyor and the consistency between the surveyors are compared by the intraclass correlation coefficient (ICC).

Results

Among the 50 patients, there were 18 males and 32 females, aged from 10 to 18 years (mean age of 14.4 years). The time of measuring Cobb angle by software method was significantly shorter than that by protractor method (94.7 ​± ​8.5s versus 217.9 ​± ​24.1s, t ​= ​−60.536, P ​< ​0.05). There was no significant difference in Cobb angle measured by software method and PACS method (all P ​> ​0.05). The reliability analysis showed that the three surveyors used software to measure the Cobb angle of the coronal main curve, TK, TLK and LL were all in good consistency (ICC>0.90). The repeatability and consistency of the software method used by the three surveyors were higher than that of the protractor method (ICC> 0.90).

Conclusions

Compared with traditional protractor, the smartphone scoliosis screening software has shorter time, higher efficiency, higher accuracy and repeatability in measuring Cobb angle of AIS, so as to widely screen the diagnosis of scoliosis patients.