HealthyNCT03134144
Chairless Chair Exoskeleton. Work-physiological-biomechanical Analysis of the Lower Extremities
A study testing Exoskeleton "Chairless Chair" in people with Healthy, run by University Hospital Tuebingen at 1 site in Germany.
Trial summary
Standing work is associated with increased risks of venous and musculoskeletal disorders; particularly low back pain is commonly reported in prolonged standing work. In manufacturing work, workstations often do not allow standing aids due to insufficient functional and spatial conditions. Read more about this study
- Who is it for?
- Ages 18 to 40 years, men onlyHealthy volunteers can take part
- Conditions the study is for
- Healthy
- What is being tested?
- Exoskeleton "Chairless Chair"
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 46 participants
- Where
- 1 siteGermany
- Study dates
- 1 May 2017to 15 Oct 2017
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 40 years
- Men only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Age: between 18 and 40 years old;
- Gender: male;
- Voluntary informed consent (oral and written) is obligatory for study participation.
Who cannot join
- Age: <18 and >40 years old;
- Gender: female;
- People under the influence of intoxicants, analgesics, or muscle relaxants;
- Alcohol abuse;
- People with cardiovascular diseases;
- People with a heart pacemaker;
Show all 12Show fewer
- People with a disability who, due to their restriction at a workplace of this kind, will not be able to participate;
- People with Diabetes Mellitus;
- People with severe muscle contractions of the lower extremities, back or arms;
- People with acute ailments or pain;
- People who are unable to complete the examination program due to language or cognitive obstacles;
- Depending on the degree of severity, people with diseases of the veins and joints of the lower extremities, spine, muscle disorders, symptomatic neurological-psychiatric diseases, acute pain syndromes, maladies or other current diseases.
Trial locations and contacts
1 site in 1 country.
Germany1 site
Institute for Occupational and Social Medicine and Health Services Research, University Hospital Tübingen, Faculty of Medicine, Eberhard Karls University Tübingen
Tübingen, Baden-Wurttemberg, 72074
About this study
Standing work is associated with increased risks of venous and musculoskeletal disorders; particularly low back pain is commonly reported in prolonged standing work. In manufacturing work, workstations often do not allow standing aids due to insufficient functional and spatial conditions. In 2014, the car manufacturer Audi introduced the lower leg exoskeleton developed by Noonee to their employees working in the factories. This exoskeleton, the 'Chairless Chair' has the advantage that standing work can be performed while technically sitting on this device. The exoskeleton offers the potential for reduced awkward body postures, but it is unclear which physiological and biomechanical loads are influenced and how. This proposal provides a study design evaluating the 'Chairless Chair' in a laboratory setting, by testing its effectiveness in terms of physiological and biomechanical parameters. It is suggested to compare different assembly tasks while wearing the exoskeleton, compared with not wearing the exoskeleton. The 'Chairless Chair' is developed in one size only, which is why we propose to include participants of different body height, which will enable us to investigate whether body height influences the effectiveness of wearing the device.
Read the detailed description
Each participant was exposed to all experimental conditions, which were the following:
- Standing without the exoskeleton
- Sitting with the exoskeleton
For both experimental conditions, the working height was adjusted to the individual to become optimal. The working distance to the simulated assembly tasks was also adjusted to the individual to become optimal. Both the working height and distance were based on textual guidelines provided in DIN EN ISO 14738:2009-07.
Each work cycle consisted of assembling and disassembling the following three tasks:
- Screwing
- Clip fitting
- Cable mounting
In addition, we investigated suboptimal working heights and distances. The results of these suboptimal conditions will not be reported in the results on this website, but in a separate publication.
- Conditions
- Healthy
- Being tested
- Exoskeleton "Chairless Chair"
- Keywords
- Exoskeleton, Manual materials handling, Musculoskeletal disorders, Posture, Standing work, Muscle activity
- Medical subject headings
- Musculoskeletal Diseases
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Exoskeleton "Chairless Chair"Device
One solution to reduce the exposure of employees to associated risks for developing work-related musculoskeletal disorders is to use exoskeletons. Using such a device in dynamic environments has the advantage over, e.g., robotics because it does not need any programming or teaching of robots. Moreover, exoskeletons are worn at the body and do not have to overcome spatial issues. In a recent review, 26 different exoskeletons have been described of which only two were designed to support the lower body during heavy work (de Looze et al. 2015). For lower intensive work tasks, like assembly tasks in the automobile industry, no study has focused on using exoskeletons to relieve employees while performing the work standing.
| Study group | Role | What they receive |
|---|---|---|
| First without exoskeleton then with exoskeleton | Experimental | Subject will perform the conditions as described under "model description" first without the exoskeleton and then with the exoskeleton. Receives: Device: Exoskeleton "Chairless Chair" |
| First with exoskeleton then without exoskeleton | Experimental | Subject will perform the conditions as described under "model description" first with the exoskeleton and then without the exoskeleton. Receives: Device: Exoskeleton "Chairless Chair" |
What is being measured
The primary outcome is the main question the study is designed to answer.
Center of Pressure
Indicator for the balance of the study participants. This outcome was measured using a force plate, in which the anteroposterior and mediolateral directions of the center of pressure are recorded. The center of pressure is a visual projection of the center of mass of the participant. For the anteroposterior direction of the center of pressure, a positive value [mm] represents the anterior direction and a negative value [mm] represents the posterior direction. For the mediolateral direction of the center of pressure, a positive value [mm] represents the right-lateral direction and a negative value [mm] represents the left-lateral direction.
For this outcome, we recorded the anteroposterior direction of the center of pressure.
The outcome is in mm, where neg. reflects the posterior direction and pos. the anterior direction.
Measured: 10 minutes of 2 hours
Muscle Activity of the Lower Back (M. Erector Spinae Lumbalis)
Indicator for the muscular load in the lower back (M. erector spinae lumbalis) that may change when wearing the passive exoskeleton.
The muscle activity was recorded using bipolar surface electromyography, during which two electrodes are placed on the muscle belly. The absolute value of muscle activity recordings is in microvolt, but since this is difficult to interpret, we have normalized this to a reference voluntary contraction that was executed by each participant prior to the experiment. The unit of measure for normalized muscle activity therefore is a percentage, i.e. a percentage of the electrical activity during the reference voluntary contraction [%RVE].
Measured: 10 minutes of 2 hours
Secondary outcomes (3)
Back Posture: Upper Back Forward Flexion Angle With Respect to the Perpendicular (Earth)
The posture of the back may indicate whether the relative body posture changed when wearing the passive exoskeleton compared to not wearing the passive exoskeleton.
In the current study, back posture was recorded using two gravimetric position sensors placed on the thoracic vertebrae T3 and lumbal vertebrae L3.
The difference between both position sensors represented the trunk forward flexion angle [°].
Measured: 10 minutes of 2 hours
Subjective Feeling of Overall Discomfort
Indicate whether participants develop feelings of discomfort in different experimental conditions when wearing or not wearing the passive exoskeleton.
Discomfort was recorded using an 11-point numeric rating scale, running from 0 (no discomfort at all) to 10 (maximally imaginable discomfort).
So, the outocme is in [units on a scale from 0 to 10].
Measured: 10 minutes of 2 hours
Participant Evaluation
A questionnaire indicating whether wearing the passive exoskeleton during simluated assembly tasks is evaluated as comfortable, feasible, and usable.
Below, the 10 statements questions as part of the participant evaluation questionnaire are shown with an interpretation of the score.
1 generally reflects "I do not agree at all" whereas 10 generally reflects "I fully agree".
Depending on the question, a score closer or equal to 1 is better and 10 worse, or vice versa.
Statements 1-8: a higher score (i.e., close to 10) is considered better Statements 9-10: a lower score (i.e., close to 1) is considered better
Measured: 2 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Apr 2017
- Study start1 May 2017
- Primary completion15 Oct 2017
- Study completion15 Oct 2017
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for HealthyStudies of the same condition, open and under way.
- More trials run by University Hospital TuebingenThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Enrolment
- 46 participants (actual)
Sponsor and investigators
- Lead sponsor
- University Hospital Tuebingen
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Dr. Tessy Luger, University Hospital Tuebingen
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03134144
- Sponsor's protocol ID
- UKT-2017-AS0-1569
- Status last verified
- Jun 2020
- First submitted
- 25 Apr 2017
- Last updated
- 16 Jun 2020
- Results posted
- Yes, on ClinicalTrials.gov
- FDA-regulated drug
- No
- FDA-regulated device
- No
Publications
Luger T, Seibt R, Cobb TJ, Rieger MA, Steinhilber B. Influence of a passive lower-limb exoskeleton during simulated industrial work tasks on physical load, upper body posture, postural control and discomfort. Appl Ergon. 2019 Oct;80:152-160. doi: 10.1016/j.apergo.2019.05.018. Epub 2019 May 30.
PubMed 31280799Luger T, Cobb TJ, Seibt R, Rieger MA, Steinhilber B. Subjective Evaluation of a Passive Lower-Limb Industrial Exoskeleton Used During simulated Assembly. IISE Transactions on Occupational Ergonomics and Human Factors, 2018.
Study at a glance
From the registry record, last updated by the sponsor on 16 Jun 2020. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Chairless Chair Exoskeleton. Work-physiological-biomechanical Analysis of the Lower Extremities
- ClinicalTrials.gov ID
- NCT03134144
- Acronym / sponsor ID
- UKT-2017-AS0-1569
- Conditions
- Healthy
- Keywords
- Exoskeleton, Manual materials handling, Musculoskeletal disorders, Posture, Standing work, Muscle activity
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 46 participants (actual)
- Lead sponsor
- University Hospital TuebingenUniversity, hospital or other
- Study start
- 1 May 2017 (actual)
- Primary completion
- 15 Oct 2017 (actual)
- Study completion
- 15 Oct 2017 (actual)
- First posted
- 28 Apr 2017 (actual)
- Results
- Posted 16 Jun 2020
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Standing work is associated with increased risks of venous and musculoskeletal disorders; particularly low back pain is commonly reported in prolonged standing work. In manufacturing work, workstations often do not allow standing aids due to insufficient functional and spatial conditions. In 2014, the car manufacturer Audi introduced the lower leg exoskeleton developed by Noonee to their employees working in the factories. This exoskeleton, the 'Chairless Chair' has the advantage that standing work can be performed while technically sitting on this device. The exoskeleton offers the potential for reduced awkward body postures, but it is unclear which physiological and biomechanical loads are influenced and how. This proposal provides a study design evaluating the 'Chairless Chair' in a laboratory setting, by testing its effectiveness in terms of physiological and biomechanical parameters. It is suggested to compare different assembly tasks while wearing the exoskeleton, compared with not wearing the exoskeleton. The 'Chairless Chair' is developed in one size only, which is why we propose to include participants of different body height, which will enable us to investigate whether body height influences the effectiveness of wearing the device.
Detailed description
Each participant was exposed to all experimental conditions, which were the following:
- Standing without the exoskeleton
- Sitting with the exoskeleton
For both experimental conditions, the working height was adjusted to the individual to become optimal. The working distance to the simulated assembly tasks was also adjusted to the individual to become optimal. Both the working height and distance were based on textual guidelines provided in DIN EN ISO 14738:2009-07.
Each work cycle consisted of assembling and disassembling the following three tasks:
- Screwing
- Clip fitting
- Cable mounting
In addition, we investigated suboptimal working heights and distances. The results of these suboptimal conditions will not be reported in the results on this website, but in a separate publication.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| First without exoskeleton then with exoskeleton | Experimental | Device: Exoskeleton "Chairless Chair"Subject will perform the conditions as described under "model description" first without the exoskeleton and then with the exoskeleton. |
| First with exoskeleton then without exoskeleton | Experimental | Device: Exoskeleton "Chairless Chair"Subject will perform the conditions as described under "model description" first with the exoskeleton and then without the exoskeleton. |
Who may qualify
- Ages
- 18 to 40 years
- Sex
- Male only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- Age: between 18 and 40 years old;
- Gender: male;
- Voluntary informed consent (oral and written) is obligatory for study participation.
Key exclusion criteria (12 listed)
- Age: <18 and >40 years old;
- Gender: female;
- People under the influence of intoxicants, analgesics, or muscle relaxants;
- Alcohol abuse;
- People with cardiovascular diseases;
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Exoskeleton "Chairless Chair"One solution to reduce the exposure of employees to associated risks for developing work-related musculoskeletal disorders is to use exoskeletons. Using such a device in dynamic environments has the advantage over, e.g., robotics because it does not need any programming or teaching of robots. Moreover, exoskeletons are worn at the body and do not have to overcome spatial issues. In a recent review, 26 different exoskeletons have been described of which only two were designed to support the lower body during heavy work (de Looze et al. 2015). For lower intensive work tasks, like assembly tasks in the automobile industry, no study has focused on using exoskeletons to relieve employees while performing the work standing. | Device | First with exoskeleton then without exoskeleton, First without exoskeleton then with exoskeleton |
Primary outcome
Center of Pressure
Time frame: 10 minutes of 2 hours
Indicator for the balance of the study participants. This outcome was measured using a force plate, in which the anteroposterior and mediolateral directions of the center of pressure are recorded. The center of pressure is a visual projection of the center of mass of the participant. For the anteroposterior direction of the center of pressure, a positive value [mm] represents the anterior direction and a negative value [mm] represents the posterior direction. For the mediolateral direction of the center of pressure, a positive value [mm] represents the right-lateral direction and a negative value [mm] represents the left-lateral direction. For this outcome, we recorded the anteroposterior direction of the center of pressure. The outcome is in mm, where neg. reflects the posterior direction and pos. the anterior direction.
Muscle Activity of the Lower Back (M. Erector Spinae Lumbalis)
Time frame: 10 minutes of 2 hours
Indicator for the muscular load in the lower back (M. erector spinae lumbalis) that may change when wearing the passive exoskeleton. The muscle activity was recorded using bipolar surface electromyography, during which two electrodes are placed on the muscle belly. The absolute value of muscle activity recordings is in microvolt, but since this is difficult to interpret, we have normalized this to a reference voluntary contraction that was executed by each participant prior to the experiment. The unit of measure for normalized muscle activity therefore is a percentage, i.e. a percentage of the electrical activity during the reference voluntary contraction [%RVE].
3 secondary outcomes
Back Posture: Upper Back Forward Flexion Angle With Respect to the Perpendicular (Earth)
Time frame: 10 minutes of 2 hours
Subjective Feeling of Overall Discomfort
Time frame: 10 minutes of 2 hours
Participant Evaluation
Time frame: 2 hours
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 16 Jun 2020.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Results publication: PubMed 31280799Luger T, Seibt R, Cobb TJ, Rieger MA, Steinhilber B. Influence of a passive lower-limb exoskeleton during simulated industrial work tasks on physical load, upper body posture, postural control and discomfort. Appl Ergon. 2019 Oct;80:152-160. doi: 10.1016/j.apergo.2019.05.018. Epub 2019 May 30.
- Results publicationLuger T, Cobb TJ, Seibt R, Rieger MA, Steinhilber B. Subjective Evaluation of a Passive Lower-Limb Industrial Exoskeleton Used During simulated Assembly. IISE Transactions on Occupational Ergonomics and Human Factors, 2018.
- Page 78: oral presentation of the study at the PREMUS 2019 conference in Bologna, Italy.Link provided by the sponsor.
- Page 284: Poster presentation of the study at the IEA 2018 conference in Florence, Italy.Link provided by the sponsor.
Related trials for Healthy
Recruiting
THE EFFECTS OF GAME-BASED EXERCISE PROGRAMS
Physical Activity, Body Image
Not yet recruitingPhase 1
A Phase I Study of GLR2053 Tablets in Chinese Healthy Adult Participants
Atopic Dermatitis
Recruiting
Colon-delivered Riboflavin and Gut Microbiota Composition
Microbiome Dysbiosis, Gut Health
Not yet recruiting
Neuroergonomic Analysis of a Brain-Computer Interface Device (BCI)
Healthy Volunteers - Male and Female
RecruitingPhase 1
First-in-Human Trial to Assess REGN20423 in Healthy Adult Participants and Adult Participants With Atopic Dermatitis
Healthy Volunteer, Atopic Dermatitis
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Exoskeleton "Chairless Chair" in people with Healthy, run by University Hospital Tuebingen at 1 site in Germany.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 16 Jun 2020. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Germany. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Yes. Results are posted in the registry (first posted 16 Jun 2020). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Center of Pressure (time frame: 10 minutes of 2 hours). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03134144, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 16 Jun 2020.