Effect of Muscle Fatigue on Spinal Imbalance and Motion in Lumbar Spinal Stenosis

Study Overview
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Brief Summary
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This study assesses spinal imbalance and motion in patients with sLSS and elicits fatigue via back exercises and compares spinal imbalance and motion before and after the fatigue exercise and compares these to healthy controls, allowing to associate sLSS-specific motion patterns to paraspinal muscle fatigue.

Detailed Description
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Symptomatic lumbar spinal stenosis (sLSS) is a common syndrome affecting the human spine characterized by age related degeneration of the lumbar discs and facet joints resulting in pain, limited function and compromised quality of life. In a healthy spine, global and local spinal loads during static posture and dynamic motion will have minimal effects on the spinal canal. However, spinal loads altered by the presence of sLSS may result in further narrowing of the spinal canal and compression of the neural elements or in overloading of the already degenerated lumbar segments possibly eliciting typical pain symptoms This study assesses spinal imbalance and motion in patients with sLSS and elicits fatigue via back exercises and compares spinal imbalance and motion before and after the fatigue exercise and compares these to healthy controls, allowing to associate sLSS-specific motion patterns to paraspinal muscle fatigue. Additional data generated using magnetic resonance tomography allows detecting and assessing differences in muscle degeneration between sLSS patients and healthy controls. Radiological images from the spine in upright position using EOS, a specialized low-dose x-ray unit will be obtained to allow the calculation of the actual clinical global and local spinal imbalance. The data obtained here are pilot data that will be critical for designing a larger clinical trial and produce important information for adapting musculoskeletal spine models to simulate spinal imbalance and motion.

Official Title
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MuscLSS: Effect of Muscle Fatigue on Spinal Imbalance and Motion in Lumbar Spinal Stenosis: Single Center Observational Pilot Study

Conditions
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Lumbar Spinal Stenosis

Intervention / Treatment
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* Other: data collection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria:for patients with sLSS age > 30 years BMI < 35kg/m2 diagnosed symptomatic lumbar spinal stenosis clinical symptoms for at least 6 months intermittent neurogenic claudication with limitations of their walking ability due to symptoms in the lower back and or in one or both legs unsuccessful conservative treatment confirmation of the LSS through MRI Inclusion criteria for age-matched healthy control subjects age > 30 years BMI < 35kg/m2 Inclusion criteria for young healthy control subjects 18 years ≤ age ≤ 30 years BMI < 35kg/m2 Exclusion Criteria:for patients with sLSS inability to provide informed consent previous spine surgery use of walking aids other neurologic disorders affecting gait MRI incompatibility Exclusion criteria for age-matched healthy control subjects inability to provide informed consent previous spine surgery history of claudications use of walking aids other neurological or orthopaedic conditions that may affect gait MRI incompatibility Exclusion criteria for young healthy control subjects inability to provide informed consent previous back injury; previous spine surgery use of walking aids current injury of any kind

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with sLSS<br>Patients with Symptomatic Lumbar Spinal Stenosis (n=10) | Other: data collection<br>* The study entails the collection of clinical, functional, radiological, and biomechanical data.<br>|
| Young Controls<br>Young healthy control subjects (n=10) | Other: data collection<br>* The study entails the collection of clinical, functional, radiological, and biomechanical data.<br>|
| Age-Matched Controls<br>Age-matched healthy control subjects (n=10) | Other: data collection<br>* The study entails the collection of clinical, functional, radiological, and biomechanical data.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Global spinal imbalance assessed using motion capture | Global spinal imbalance calculated from markers placed on specific anatomical landmarks: electromyographic (EMG) electrode placement bilaterally on the multifidus, erector spinae (longissimus), erector spinae (iliocostalis), transversus abdominis, gluteus medius, vastus medialis, tibialis anterior and gastrocnemius medialis muscles. The curvature of the lumbar region during natural stance, natural seated posture, maximum trunk flexion, maximum trunk extension and during walking will be computed from the marker data. A cubic polynomial function will be fit to the marker positions in each time frame, approximating an S-shaped spine curvature with thoracic kyphosis and lumbar lordosis curves and the curvature of the lumbar spine will be computed for each task. | approximate duration: 30 minutes at baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Global spinal imbalance assessed using EOS (upright standing sagittal plane EOS images of the full body including entire spine and pelvis) | Static global and local spinal imbalance will be assessed on the EOS images as the C7 plumb line (C7PL), sagittal vertical axis (SVA) and spinosacral angle (SSA). The discrepancy between SSA and SVA are a sign of the prevalence of static compensation mechanism. The correction angle to a balanced situation will be measured using the full balance integrated method. | approximate duration: 10 minutes at baseline | 
| Dynamic global spinal imbalance | Dynamic spinal imbalance will be assessed as the difference between spinal imbalance during walking compared to standing. | one time assessment at baseline | 
| Difference in global spinal imbalance between the fatigued and non-fatigued state | The curvature of the lumbar region between the fatigued and non-fatigued state will be computed from the marker data. | one time assessment at baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Symptomatic Lumbar spinal stenosis (sLSS), Spinal motion, Spinal loading, Spinal imbalance, Paraspinal muscle fatigue, Muscle degeneration, EOS medical imaging