The Effects of Balanced Seating Pressure on Pelvic Asymmetry: A Pilot Study
NCT ID: NCT07062510
Last Updated: 2026-01-27
Study Results
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.
RECRUITING
NA
20 participants
INTERVENTIONAL
2025-09-12
2026-05-15
Brief Summary
Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.
1. Does the DaSuit® cushion distribute the pressure evenly on both under-buttock pressure compared to a placebo cushion?
2. Does the DaSuit® cushion improve spinal alignment compared to a placebo cushion?
3. What discomfort or adverse events do participants experience when using the DaSuit® cushion?
Researchers will compare the DaSuit® cushion to a placebo cushion (a look-alike cushion without therapeutic effect) to see if the DaSuit® cushion works to relieve sitting-induced discomfort.
Participants will:
1. Use the DaSuit® cushion or a placebo cushion in a randomized order, with each sitting session lasting 10 minutes
2. Complete both conditions with a 10-minute washout period between sessions
3. Sit on a standardized wooden chair with a pressure sensor mat placed on the cushion surface
4. Keep a fixed posture with hips, knees, and ankles at approximately 90 degrees
5. Watch a 10-minute video on a tablet positioned 30-40 cm in front of them at a 5-10 degree downward angle to maintain a steady gaze
6. Undergo spinal imaging immediately after each session, maintaining the same seated posture
7. Report any discomfort or pain experienced during or after each session
Related Clinical Trials
Explore similar clinical trials based on study characteristics and research focus.
Upright Back Posture Device Study
NCT03769246
Foot Orthoses in Patients with Sciatica
NCT05129540
The Rehabilitation Outcome of Patients With Lumbar Spondylolisthesis. A Prospective Randomized Study
NCT02435485
Benefit of Lumbar Bracing for Chronic Low Back Pain Due to Degenerative Disc Disease
NCT03484403
Effectiveness of Inelastic LSO Versus Standard Medical Treatment for Back Pain Associated With Kyphosis
NCT02180776
Detailed Description
Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.
Participants The study will not involve patients or the public in the design, conduct, reporting, or dissemination.
Inclusion criteria are as follows: (1) adults aged 20 to 50 years; (2) experiencing non-specific low back pain exacerbated by sitting, with a VAS score between 3 and 7; (3) height between 150-180 cm; (4) BMI between 18.5-24; and (5) radiographically verified hemi-pelvic height discrepancy ≥ 0.5 cm in a seated posture.
Exclusion criteria include: (1) inability to sit for 20 minutes; (2) MMSE \< 24; (3) significant spinal or pelvic disorders (e.g., fractures, prior surgeries, herniated discs with nerve compression); (4) diagnosed scoliosis with a Cobb angle ≥ 20°; (5) recent use of analgesics or muscle relaxants; (6) pregnancy; and (7) skin conditions affecting sitting tolerance. All participants will provide written informed consent following clinical pelvic examination confirming asymmetry.
Interventions Each participant will undergo both intervention conditions in a randomized order. In each session, the participant will sit for 10 minutes on either the DaSuit® cushion or the placebo cushion, placed on a standardized 40×40×40 cm wooden chair. A pressure sensor mat will be placed on the cushion surface to measure under-buttock pressure. Following the sitting period, pain intensity will be assessed using the VAS, and an anterior-posterior full-spine X-ray will be taken. After a 10-minute washout period-during which the participant will be instructed to walk-the alternate cushion condition will be administered.
Outcome Measures Adverse events will be monitored throughout the study. Participants will be asked to report any discomfort or pain during or after each session. No adverse events are expected.
Primary outcomes include:
Under-buttock pressure:
* X and Y coordinates of center of force
* Total force applied to the cushion
* Area of force distribution
* Maximum pressure (mmHg)
* Area exceeding a defined percentage of maximum pressure
* Right/Left peak pressures
* Distance from center of force to Right/Left peak pressure points
Spinal alignment parameters:
* Spinal alignment deviation (SAD; C7-S1) Participants will again sit upright on the test chair without a cushion, and a frontal full-spine radiograph will be taken. The deviation will be calculated as the horizontal distance between the vertical lines passing through the center of the seventh cervical vertebra (C7 plumb line) and the center of the first sacral vertebra (S1 plumb line). This measurement reflects the lateral displacement of the spine and serves as an indicator of coronal imbalance.
* Pelvic height discrepancy (PHD) Pelvic height discrepancy (PHD) will be determined by measuring the vertical distance between the highest point of the iliac crest and the lowest point of the ischial tuberosity on both sides. A side-to-side difference of ≥0.5 cm will be used as the diagnostic threshold for pelvic asymmetry.
* Shoulder height discrepancy (SHD) While shoulder height discrepancy (SHD) is listed as a secondary outcome, its assessment will be based on the vertical difference between the acromion landmarks on both sides, if visible within the imaging field.
Pain intensity, measured via the visual analog scale (VAS)
Instrumentation and Procedures Pressure Mapping and Sitting Protocol: The cushion will be positioned on a 40×40×40 cm wooden box serving as a chair, with a pressure mat placed on top. Participants will sit with hips, knees, and ankles at approximately 90° angles. A tablet will be mounted at 30-40 cm distance and a downward viewing angle of 5-10° to maintain visual focus and reduce head movement. Participants will sit for one minute to acclimate, after which under-buttock pressure will be recorded continuously for 10 minutes.
Radiographic Procedure: For spinal imaging, the chair will be placed on a 20 cm X-ray platform. A 40×40×20 cm footrest will ensure consistent lower limb positioning during imaging. The imaging field will extend from the external auditory meatus to the seat base. Participants will maintain a natural sitting posture for 10 seconds prior to image capture.
Randomization and Blinding Randomization will be performed using a computer-generated sequence with a 1:1 allocation ratio. The sequence will be prepared by an independent statistician not involved in recruitment or data collection. Allocation concealment will be achieved through the use of sequentially numbered, opaque, sealed envelopes (SNOSE), managed by staff independent of the enrollment process. Both the DaSuit® and placebo cushions are designed to be visually indistinguishable. Participants will be blinded to the cushion type. However, due to logistical constraints, outcome assessors will not be blinded.
Statistical Analysis As a pilot study, the primary objective is to assess feasibility and obtain preliminary effect estimates for planning future trials. The sample size is not based on formal power calculations and results should be interpreted with caution regarding external validity.
Within-subject comparisons between the DaSuit and placebo conditions will be analyzed using paired t-tests. To examine potential sequence effects, between-group comparisons (Group A vs. Group B) will be conducted using independent t-tests. A two-tailed p-value of \< 0.05 will be considered statistically significant.
All analyses will use complete case data; missing data are not anticipated. If missingness exceeds 10% in future trials, per-protocol analysis will serve as the primary strategy, supplemented by sensitivity analyses as appropriate.
Conditions
See the medical conditions and disease areas that this research is targeting or investigating.
Study Design
Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.
RANDOMIZED
CROSSOVER
TREATMENT
QUADRUPLE
Study Groups
Review each arm or cohort in the study, along with the interventions and objectives associated with them.
Dasuit to Placebo
This group of patients will first undergo Dasuit intervention then Placebo intervention
Dasuit Cusion
The Dasuit cushion is placed on a 40X40X40 wooden box as a chair, and the pressure seating mat is placed on the cushion. Participants were asked to sit on the cushion with hips, knees, and ankles positioned at approximately 90° angles at ease. A tablet was mounted in front of the chair at 30-40 cm from the eyes and at a downward viewing angle of 5-10 degrees. Participants were instructed to watch a 10-minute video to maintain a fixed gaze and minimize head movement. The patient was to sit on the cushion at ease for 1 minute to adjust to the cushion, then under-buttock pressure was recorded for 10 mins.
Placebo
The placebo cushion is placed on a 40X40X40 wooden box as a chair, and the pressure seating mat is placed on the cushion. Participants were asked to sit on the cushion with hips, knees, and ankles positioned at approximately 90° angles at ease. A tablet was mounted in front of the chair at 30-40 cm from the eyes and at a downward viewing angle of 5-10 degrees. Participants were instructed to watch a 10-minute video to maintain a fixed gaze and minimize head movement. The patient was to sit on the cushion at ease for 1 minute to adjust to the cushion, then under-buttock pressure was recorded for 10 mins.
Washout
A 10 min washout period is in between the two interventions. The paitent is asked to walk around at ease.
Placebo to Dasuit
This group of patients will first undergo Placebo intervention then Dasuit intervention
Dasuit Cusion
The Dasuit cushion is placed on a 40X40X40 wooden box as a chair, and the pressure seating mat is placed on the cushion. Participants were asked to sit on the cushion with hips, knees, and ankles positioned at approximately 90° angles at ease. A tablet was mounted in front of the chair at 30-40 cm from the eyes and at a downward viewing angle of 5-10 degrees. Participants were instructed to watch a 10-minute video to maintain a fixed gaze and minimize head movement. The patient was to sit on the cushion at ease for 1 minute to adjust to the cushion, then under-buttock pressure was recorded for 10 mins.
Placebo
The placebo cushion is placed on a 40X40X40 wooden box as a chair, and the pressure seating mat is placed on the cushion. Participants were asked to sit on the cushion with hips, knees, and ankles positioned at approximately 90° angles at ease. A tablet was mounted in front of the chair at 30-40 cm from the eyes and at a downward viewing angle of 5-10 degrees. Participants were instructed to watch a 10-minute video to maintain a fixed gaze and minimize head movement. The patient was to sit on the cushion at ease for 1 minute to adjust to the cushion, then under-buttock pressure was recorded for 10 mins.
Washout
A 10 min washout period is in between the two interventions. The paitent is asked to walk around at ease.
Interventions
Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.
Dasuit Cusion
The Dasuit cushion is placed on a 40X40X40 wooden box as a chair, and the pressure seating mat is placed on the cushion. Participants were asked to sit on the cushion with hips, knees, and ankles positioned at approximately 90° angles at ease. A tablet was mounted in front of the chair at 30-40 cm from the eyes and at a downward viewing angle of 5-10 degrees. Participants were instructed to watch a 10-minute video to maintain a fixed gaze and minimize head movement. The patient was to sit on the cushion at ease for 1 minute to adjust to the cushion, then under-buttock pressure was recorded for 10 mins.
Placebo
The placebo cushion is placed on a 40X40X40 wooden box as a chair, and the pressure seating mat is placed on the cushion. Participants were asked to sit on the cushion with hips, knees, and ankles positioned at approximately 90° angles at ease. A tablet was mounted in front of the chair at 30-40 cm from the eyes and at a downward viewing angle of 5-10 degrees. Participants were instructed to watch a 10-minute video to maintain a fixed gaze and minimize head movement. The patient was to sit on the cushion at ease for 1 minute to adjust to the cushion, then under-buttock pressure was recorded for 10 mins.
Washout
A 10 min washout period is in between the two interventions. The paitent is asked to walk around at ease.
Eligibility Criteria
Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.
Inclusion Criteria
2. adults had low back pain non-specific but exacerbated by sitting with VAS score between 3-7
3. body height between 150-180 cm
4. BMI between 18.5-24
5. a radiographically verified hemi-pelvic height discrepancy of ≥ 0.3 cm in sitting posture
6. willing to participate and cooperate throughout the whole intervention session
Exclusion Criteria
2. MMSE \< 24
3. significant spinal/pelvic disorders (e.g., fractures, surgeries, herniated discs with nerve compression)
4. scoliosis with Cobb angle ≥ 20°
5. recent use of pain killers and/or muscle relaxants
6. pregnancy
7. skin conditions affecting sitting tolerance.
20 Years
50 Years
ALL
No
Sponsors
Meet the organizations funding or collaborating on the study and learn about their roles.
Chang Gung Memorial Hospital
OTHER
Responsible Party
Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.
Principal Investigators
Learn about the lead researchers overseeing the trial and their institutional affiliations.
Yu-Cheng Pei, M.D, PhD.
Role: STUDY_DIRECTOR
Chang Gung Memorial Hospital
Locations
Explore where the study is taking place and check the recruitment status at each participating site.
Taoyuan Chang Gung Memorial Hospital
Taoyuan District, Taiwan, Taiwan
Countries
Review the countries where the study has at least one active or historical site.
Central Contacts
Reach out to these primary contacts for questions about participation or study logistics.
Facility Contacts
Find local site contact details for specific facilities participating in the trial.
Other Identifiers
Review additional registry numbers or institutional identifiers associated with this trial.
2303070089
Identifier Type: -
Identifier Source: org_study_id
More Related Trials
Additional clinical trials that may be relevant based on similarity analysis.