Table 1.

Flexion/Extension (From Extended to Flexed-Position Ranges of Motion)^*

Level	Avg	SD	Min	Max
Rotations (°) around x-axis
L1–2	11.9	2.27	8.6	17.9
L2–3	14.5	2.29	9.5	19.1
L3–4	15.3	2.04	11.9	21.0
L4–5	18.2	2.99	11.6	25.6
L5-Sacrum	17.0	4.33	6.3	23.7
Translations (mm) of Point A in z-direction
L1–2	2.6	1.05	0.3	4.1
L2–3	3.0	1.15	1.2	7.0
L3–4	3.1	1.19	0.3	6.7
L4–5	2.6	1.16	0.3	5.8
L5-Sacrum	−0.9	1.54	−3.8	1.8
Translations (mm) of Point A in y-direction
L1–2	3.3	1.52	−0.4	6.8
L2–3	4.5	1.33	2.7	7.5
L3–4	4.7	1.67	−0.5	8.6
L4–5	5.9	1.78	2.4	11.6
L5-Sacrum	4.4	1.62	−0.7	7.1
Translations (mm) of Point B in z-direction
L1–2	10.7	2.14	6.3	15.1
L2–3	12.2	2.19	8.4	19.5
L3–4	12.3	2.36	6.6	18.3
L4–5	12.3	2.66	7.4	21.1
L5-Sacrum	6.5	2.94	−0.3	12.4
Translations (mm) of Point B in y-direction
L1–2	2.9	1.93	−2.0	7.0
L2–3	5.3	1.80	2.6	9.6
L3–4	6.3	2.09	1.3	10.8
L4–5	9.0	2.21	4.2	14.9
L5-Sacrum	8.7	3.00	1.7	16.1

^*Normal kinematic values of flexion-extension movement. Rx is an average from both the computer assisted method (CAM) and the manual measurement by graphic construction method (GCM) techniques.

Avg = average; SD = standard deviation; Min = minimum; Max = maximum.