Radial and palmar active range of motion measurement: reliability of six methods in healthy adults.

The current study aims to assess the reliability of 6 range-of-motion measurement methods for the thumb carpometacarpal joint: Pollexograph-thumb, Pollexograph-metacarpal, radius-metacarpal goniometry, intermetacarpal goniometry, intermetacarpal distance, and thumb-distal-interphalangeal distance. A senior hand surgeon, an experienced resident, and a less experienced research fellow evaluated the dominant hands of 29 healthy subjects. All 6 methods were performed for radial adduction, radial abduction, and palmar abduction, but only distance methods were measured for palmar adduction. Intrarater and interrater reliability were computed using intraclass correlation coefficient, standard error of measurement, and smallest detectable difference. Pollexograph-thumb method showed the highest active range of movement for radial adduction (12°) and abduction (71°), while all the other angular methods resulted in approximately 20° for radial adduction and 50° for radial abduction. Distance methods showed comparable mean results for radial and palmar range of motion (adduction/abduction): intermetacarpal distance (50 mm/60 mm) and thumb-distal-interphalangeal distance (50 mm/120 mm). Interrater reliability using the results of the intraclass correlation coefficient demonstrates that Pollexograph-thumb and Pollexograph-metacarpal showed excellent reliability for radial adduction and abduction, whereas Pollexograph-thumb method revealed the best reliability for palmar abduction. Moreover, thumb-distal-interphalangeal distance also showed excellent reliability for radial and palmar abduction. Conventional goniometry showed a large variety of reliability results, ranging from poor to excellent. No clinical benefit can be derived from assessing the palmar adduction. We found that the Pollexograph-thumb showed excellent reliability results throughout all measurements. Thumb-distal-interphalangeal-joint distance is especially valuable for assessing radial and palmar abduction.