Group of symptomatic individuals with LDH confirmed in MRI.

Group of asymptomatic individuals with no LDH.

Every individual will be examined with a non-invasive "G-Walk" device which is a sensor mounted on a belt and fasten on individuals' lumbar spine region during two test activities: Timed up and go and 6-meter walk tests. Data collection will include kinematic parameters. Oswestry Disability Index (ODI) score will also be collected.

The sensor mounted on the belt in lumbar 2nd (L2) vertebra. Following data will be obtained:

Spatio-temporal parameters standing phase, sitting phase and rotations, trunk kinematics (flexion and/or extension angle) will be collected.

The sensor mounted on the belt in lumbar 5th (L5) vertebra. Following data will be obtained:

Total distance travelled general spatio-temporal parameters, variation in spatio-temporal parameters during the 6 minutes walking, pelvis kinematics

The Oswestry Disability Index (ODI) is a valid and reliable assessment tool used by clinicians and researchers to quantify disability for low back pain. The self-completed questionnaire contains ten sections concerning intensity of pain, lifting, ability to care for oneself, ability to walk, ability to sit, sexual function, ability to stand, social life, sleep quality, and ability to travel.

For each section the total possible score is 5: if the first statement is marked the section score = 0; if the last statement is marked, it = 5. After completing, the score is calculated by by summing scores from all sections (total maximum points=50). Total results are calculated as a percentage. The higher the score, the subject's condition is worse.

The results are interpreted as follows:

0% to 20%: minimal disability 21%-40%: moderate disability 41%-60%: severe disability 61%-80%: crippled 81%-100%:These patients are either bed-bound or exaggerating their symptoms.