J Korean Orthop Assoc JKOA Journal of the Korean Orthopaedic Association 1226-2102 The Korean Orthopaedic Association 10.4055/jkoa.2007.42.5.593 Original Article The Validity and Reliability of the EMC Device; For the Checking of the Mobility of the First Ray of the Foot Kim J-Young M.D. Lee Kyung Tai M.D. Young Ki Won M.D. Park Ye Soo M.D. * Jeong Ju Seon M.D. Hwang Seung Keun M.D. Department of Orthopedic Surgery, Eulji General Hospital, Eulji University, Seoul, Korea. Department of Orthopedic Surgery, College of Medicine, Hanyang University, Seoul, Korea. Address reprint requests to Seung Keun Hwang, M.D. Department of Orthopedic Surgery, Eulji General Hospital, Eulji University, 280-1, Hagye-dong, Nowon-gu, Seoul 139-711, Korea. Tel: +82.2-970-8036, Fax: +82.2-973-3024, seungkeunh@hotmail.com 10 2007 31 10 2007 42 5 593 598 Copyright © 2007 The Korean Orthopaedic Association 2007 Purpose

To evaluate the validity and intra-rater, inter-rater reliability of the EMC device used to check the mobility of the first ray of the foot.

 Materials and Methods

Sixty-nine cases (43 patients) of mild to severe hallux valgus feet were enrolled in this study. For an analysis of the validity of the EMC device, the dorsal mobility of the first ray of the foot was measured using the modified Coleman block test and EMC device. The intra- and inter-rater reliability of EMC device was evaluated by measuring the dorsal mobility of the first ray of the foot twice with three independent raters blinded to other's results. The results were analyzed for the intra-rater reliability and for inter-rater reliability.

 Results

The mean value of the dorsal mobility of the first ray of the foot by the EMC device and modified Coleman block test was 8.3 mm (range; 4.3-12.3 mm) and 7.4 mm (range; 3.4-10.3 mm), respectively. There was a significant difference between the EMC device and modified Coleman block test (p<0.05). However, both the measured data, showed a good correlation (Pearson correlation coefficient=0.84). The paired t-test for intra-rater reliability and ANOVA testing for inter-rater reliability showed no statistically significant difference.

 Conclusion

The EMC device is reliable and valid for measuring the mobility of the first ray of the foot.

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The dorsal mobility of the first ray of the foot was measured using the modified Coleman block test.

The scatter plot shows measured data with the EMC device and the calculated data with the lateral radiographs using the modified Coleman block test.

Comparison of the Mean and Standard Deviation of the 1st Ray Dorsal Mobility of the Foot between the EMC Device and Modified Coleman Block Test

*, standard deviation.

Mean and Standard Deviation of the 1st Ray Dorsal Mobility of the Foot For Intra-rater

*, standard deviation.

Mean and Standard Deviation of the 1st Ray Dorsal Mobility of the Foot For Inter-rater

*, standard deviation