Non-invasive measurement of tendon excursion with a colour Doppler imaging system: a reliability study in healthy subjects

The excursion of the flexor digitorum profundus tendon during active flexion of the third finger was measured with colour Doppler imaging in 10 healthy volunteers. Repeated measurements were made by one observer in three sessions to assess the test-retest reliability. An analysis of variance (ANOVA) was done to find out the multiple sources of measurement error. The intraclass correlation coefficient was 0.81. For single measurements, the standard error of measurement was not more than 0.17 cm. The smallest detectable difference between two consecutive measurements was 0.48 cm. The test-retest reliability of colour Doppler measurements of excursion of the flexor digitorum profundus III tendon (FDP III) in healthy subjects is good. With series of 25 flexion movements, colour Doppler imaging is applicable in the assessment of tendon excursions in patients.