Objective
To measure the lumbar segmental range of motion (ROM) with 3-dimensional motion analysis system and compare the results with radiologic ROM measurements.

Method: Ten healthy adult volunteers were included. We attached surface markers at the corresponding skin surface of each lumbar vertebral bodies and measured lumbar segmental ROM in flexion-extension, right bending, left bending, axial rotation with 3-D motion analysis. We compared some of the results with radiologic segmental ROM measurements.

Results: In 3-D motion analysis, segmental ROM of flexion and extension, right bending, left bending, right rotation, left rotation were, respectively: 10.1^o, 45^o, 3.5^o, 1.7^o and 1.9^o (L1-L2); 17.9^o, 6.2^o, 5.1^o, 1.4^o and 1.1^o (L2-L3); 15.0^o, 7.2^o, 4.9^o, 2.1^o and 1.1^o (L3-L4); 14.9^o, 5.8^o, 4.6^o, 1.7° and 1.6° (L4-L5); 10.6^o, 4.9^o, 3.8°, 2.6° and 0.8° (L5-S1). There was no statistically significant difference in segmental ROM between 3-D motion analysis measurements and radiologic measurements except L5-S1 right bending, L2-L3 and L5-S1 left bending. No statistical significant difference in lumbar flexion and bending ROM was found between two methods.

Conclusion: 3-D motion analysis is a useful method when measuring the lumbar segmental range of motion and it has an advantage to analyze segmental lumbar motion with three directions simultaneously. (J Korean Acad Rehab Med 2003; 27: 424-432)