NCT07253493 Effect of Mechanical Loading and Bone Loss on Motor Neuron Activity-H-Reflex Relationship
| NCT ID | NCT07253493 |
| Status | Recruiting |
| Phase | — |
| Sponsor | Istanbul Physical Medicine Rehabilitation Training and Research Hospital |
| Condition | Osteoporosis Postmenopausal |
| Study Type | INTERVENTIONAL |
| Enrollment | 24 participants |
| Start Date | 2025-11-18 |
| Primary Completion | 2026-03 |
Eligibility & Interventions
Eligibility Fast-Check
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What to Expect as a Participant
You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.
This trial targets 24 participants in total. It began in 2025-11-18 with a primary completion date of 2026-03.
⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.
Brief Summary
Weight-bearing exercises (e.g., running, jumping, whole-body vibration) are widely practiced due to their beneficial effects on bone development and their role in the prevention and treatment of osteoporosis. However, the underlying neuroregulatory mechanisms responsible for these positive effects have not yet been fully understood. Two main neuromodulatory mechanisms have been proposed in the literature: (i) spinal reflexes originating from muscle spindles (stretch reflex, tonic vibration reflex), and (ii) the bone myoregulation reflex (BMR) based on load-sensitive osteocytes. It is well established that increased voluntary contraction and the associated rise in background EMG activity, that is, motor neuron pool activity, enhance muscle spindle-based reflex responses (such as the H-reflex and tendon reflex). In contrast, it has been demonstrated that the H-reflex is suppressed during bone-loading activities such as single-leg stance, jumping, or whole-body vibration. This study is based on two hypotheses: * As mechanical loading increases, Ia inhibitory effects intensify, leading to greater H-reflex suppression. * During whole-body vibration, the H-reflex is suppressed due to Ia inhibition. If this inhibition originates from load-sensitive receptors-osteocytes-and thus from the BMR, then in osteoporosis, where osteocyte number and function are reduced, H-reflex suppression will be diminished. The aim of this research is to test these hypotheses. Confirmation of these assumptions would suggest that reflex control during weight-bearing exercise occurs predominantly through osteocyte-mediated BMR mechanisms rather than muscle spindle-based mechanisms such as the stretch or tonic vibration reflex.
Eligibility Criteria
Inclusion Criteria: * Being in the postmenopausal period * For the osteoporosis group: having femoral osteoporosis (femoral neck or total femur T-score ≤ -2.5) * For the control group: having no osteoporosis or osteopenia (femoral neck and total femur T-scores \> -1, and L1-L4 and L2-L4 T-scores \> -1) * Being a volunteer Exclusion Criteria: * Receiving osteoporosis treatment * Having a peripheral or central nervous system disorder (e.g., stroke, polyneuropathy, radiculopathy, entrapment neuropathy, etc.) * Having acquired or hereditary muscle diseases (myopathies) * Having active painful lower extremity pathologies (e.g., osteoarthritis, inflammatory joint diseases, etc.) * Having cardiac arrhythmias * Having a history of other metabolic bone diseases * Having skin lesions at the electrode placement sites on the lower extremities * Being older than 65 years
Contact & Investigator
İlhan Karacan, Prof. Dr.
STUDY CHAIR
stanbul Physical Medicine Rehabilitation Training and Research Hospital
Frequently Asked Questions
Who can join the NCT07253493 clinical trial?
This trial is open to female participants only, aged 18 Years or older, up to 65 Years, studying Osteoporosis Postmenopausal. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.
Is NCT07253493 currently recruiting?
Yes, NCT07253493 is actively recruiting participants. Contact the research team at f.orhunalayoglu@gmail.com for enrollment information.
Where is the NCT07253493 trial being conducted?
This trial is being conducted at Bahçelievler, Turkey (Türkiye).
Who is sponsoring the NCT07253493 clinical trial?
NCT07253493 is sponsored by Istanbul Physical Medicine Rehabilitation Training and Research Hospital. The principal investigator is İlhan Karacan, Prof. Dr. at stanbul Physical Medicine Rehabilitation Training and Research Hospital. The trial plans to enroll 24 participants.