IMU-based kinematic data of the Five Times Sit-to-Stand Test in people with and without non-specific low back pain and visual impairment

Description

This dataset contains raw inertial measurement unit (IMU) recordings collected while participants performed the Five Times Sit-to-Stand Test (5×STS). Three Xsens IMU sensors (accelerometer + gyroscope) were placed on the sacrum, sternum and thigh, capturing trunk and lower-limb kinematics during the test.

The data were collected in two independent cohorts — Zaragoza and Madrid (Spain) — from participants classified into four groups according to a 2×2 design:

• presence or absence of non-specific chronic low back pain, and

• presence or absence of visual impairment.

For a subset of measurements, the sensors were placed on the participant either by a physiotherapist or by the participant themselves, in order to evaluate the feasibility of self-administered sensor placement for remote/tele-rehabilitation assessment. Each condition was repeated across multiple trials and, for most participants, across sessions performed on different days (test–retest).

Authors

Funding

This research was funded under reference LMP97_21 by the Government of Aragón, Spain, through the Call for R&D&I Projects in priority and multidisciplinary lines for the years 2021–2023. Principal Investigator: Dr. Pablo Herrero Gallego.

Ethical approval and informed consent

Ethical approval was granted by the Madrid Ethics Committee (CEI-120-2433). Before collecting information from participants selected for the study, they received an information sheet and signed informed consent via the HEFORA Telerehabilitation Platform.

Conflict of interest

The authors declare that there are no conflicts of interest related to this work.

How to cite

If you use this dataset, please cite:

[Add full citation once the associated publication is available.]

Dataset structure

Sensor recordings are organised as:

<Site>/<Group>/<SubjectID>/<Session>/<Placer>/<Measurement>/<SENSOR>_<SubjectID>_S<session>_<placer>_M<measurement>.csv

Example:

Datos sensores Zaragoza/SI_DOLOR_NO_DISCAPACIDAD/004/Sesión 1/PACIENTE/Medida 2/SACRO_004_S1_PAR_M2.csv

Groups and sample size

Note: the Madrid cohort does not include a NO_DOLOR_NO_DISCAPACIDAD (control) group, and some subgroups are small (particularly SI_DOLOR_SI_DISCAPACIDAD, where recruitment of participants with both conditions proved difficult). Group sizes are therefore unbalanced by design/recruitment constraints, not by data curation.

Sensor placement

Three Xsens IMU sensors (accelerometer + gyroscope, onboard sensor-fusion orientation estimate) were used:

• SACRO — fixed at the sacrum (lower back).

• ESTERNON — fixed at the sternum (chest).

• MUSLO — fixed on the thigh. The side (left/right) was not fixed and varies by participant; it is recorded per participant in the accompanying questionnaire files (PIERNA SENSOR column), see below.

Test protocol (5×STS)

Participants were seated on a standard chair without armrests, with arms crossed over the chest. On the examiner's signal, they stood up and sat down 5 times as fast as possible. Timing was recorded from the start signal until the participant was standing upright for the fifth time.

File format

Each .csv file is a raw export from the Xsens acquisition software and contains:

sep=,
DeviceTag:,<SACRO|MUSLO|ESTERNON>
FirmwareVersion:,<...>
AppVersion:,<...>
StartTime: ,<YYYY-MM-DD_HH:MM:SS_mmm TZ>
© Xsens Technologies B. V. 2005-2022

PacketCounter,SampleTimeFine,Euler_X,Euler_Y,Euler_Z,Acc_X,Acc_Y,Acc_Z,Gyr_X,Gyr_Y,Gyr_Z
0,2918501137,-27.73...,-87.52...,-13.09...,0.0,0.0,0.0,0.0,0.0,0.0
...

Nominal sampling rate: 120 Hz (SampleTimeFine increments of ~8333 µs) for the large majority of recordings. Typical recording length: ~12–18 s (consistent with a 5-repetition sit-to-stand trial).

Data collection period: 2022-11-28 to 2023-10-04.

Included files

• 3,069 sensor CSV files (SACRO/MUSLO/ESTERNON), following the naming convention described above.

• Questionnaire files (clinical/anthropometric data and dominant-leg/sensor-leg information per participant, identified only by subject code):

  • Cuestionarios Madrid/Cuestionarios Madrid.xlsx

  • Cuestionarios Zaragoza/Cuestionarios DGA Dolor Lumbar.xlsx

  • Reclutamiento Zaragoza y Madrid.xlsx

Known limitations / data quality notes

• Folder naming is not fully standardised. Session and measurement folder names vary in capitalisation/spacing across subjects (e.g. Sesión 1 / Sesion 1 / SESION 1, Medida 1 / MEDIDA 1). File names were normalised for this release, but folder names were left untouched.

• A small number of files have a sampling rate different from the 120 Hz norm (e.g. one identified case at 60 Hz). Always compute the effective sampling rate from SampleTimeFine rather than assuming a fixed value.

• One file has a StartTime of 1970-01-01, indicating the device clock was not synchronised at the time of recording; the sensor data itself is unaffected.

• In a very small number of cases the session/measurement number encoded in the filename does not match the folder that contains it; the folder path is the reliable source of truth.

License

This dataset is released under the Creative Commons Attribution 4.0 International (CC BY 4.0) license.