Measurement of spinal range of motion(ROM) can be effectively used in guiding the direction of therapy, determining the patient's response to rehabilitation treatment and functional assessment. However for a method of measurement to be commonly used in clinical and research settings, it must be easy to perform, rapid and highly reliable. The purpose of this study was to determine the possibility of clinical application of 2-dimensional motion analysis system to measure spinal ROM in patients with low back pain(LBP).

Subjects included 10 healthy males and 10 patients with LBP. Using Electronic Digital Inclinometer (EDI 320) and 2-dimensional motion analysis system, thoracic, lumbar and pelvic ROMs were measured for trunkal flexion, extension, lateral flexion and rotation. Also proportions of decreased ROMs in LBP patients relative to healthy subjects and movement patterns of each spinal segment according to time sequence were investigated.

LBP patients compared to normal subjects showed significantly low spinal ROM(P＜0.05) except thoracic and pelvic ROM for extension. When looking at the change of each spinal ROM in respect to time with motion analysis system, normal subjects showed synchronized and sigmoid motion curve time from the initiation to the end of motion in all areas of spine during 4 motions. LBP patients took longer time from the initiation to the end of each motion, and showed smaller initial change and fluctuation in spinal ROM during each motion compared to normal subjects.

The results of this preliminary study suggest that 2-dimensional motion analysis system can be effectively used for measuring spinal ROM in patients with LBP.