Kinematic and temporal analysis of the movement helps researchers and clinicians to better understand the way humans move and interact within the environment in which they live, better describe the alterations coming from impairments, and finally allow to better tailor interventions for patients. In this perspective, motion analysis has become, in the last 30 years, a remarkable and important field of research. Even if movement assessment should be a cornerstone for definition and modulation of rehabilitation interventions, there are still few motion analysis devices that are able to influence the clinical decision process; motion analysis labs are among those, but their use is unfortunately limited due to the costs of instruments and analysis. Other small unobtrusive wearable devices, easier to use and cost-effective, have been developed, like Inertial measurement units (IMU), composed by accelerometers and gyroscopes. They could therefore represent an incentive for a more widespread use of motion analysis within daily clinical activity in Rehabilitaion.

Timed Up and Go Test (TUG) is a simple, widely used, functional test which involves standing up from a chair, walking three meters, turning, and going back to sit. It is used to evaluate movement, mobility, dynamic and static balance in people with musculoskeletal impairment, neurological diseases, aging related conditions, and the quality of life in people with low back pain. The only and easy outcome considered is the time to completion. Nevertheless, the application of an IMU to a subject performing TUG can provide other objective, quantitative data, like temporal and kinematic parameters of the whole test and its sub-phases. The instrumented TUG (iTUG) has already been applied, mainly in the neurorehabilitation field, in particular for Parkinson's disease and for post-stroke impairments.

cLBP is one of the most burdensome health problem worldwide. cLBP has been considered a bio-psycho-social disease, characterized by pain in the lumbar region, functional impairments, and condition-related disability. Despite the obvious motor problems affecting people with cLBP, to the best of our knowledge, chronic low back pain (cLBP) has not yet been explored using iTUG.

The aim of study is to analyse temporal and kinematic parameters of cLBP subjects compared to BMI and age-matched healthy subjects, through iTUG and to explore the correlations of those parameters with pain and disability.

Inclusion Criteria (for Chronic Low Back Pain population):

• Pain from at least 3 months
• Numerical Pain Rating Scale (NPRS) ≥ 4

Exclusion Criteria (for Chronic Low Back Pain population):

• History of neurological impairment or disease,
• Other orthopaedic impairment within the past 6 months or surgery in the previous 6 months.

Population of Chronic Low Back Pain subjects participating to an outpatient rehabilitation program; Population of healthy subjects, age and BMI-matched with the Low Back Pian sample.