Gait and Bone Health in SMA

Dual X-Ray Absorptiometry (DXA)

Time frame: Baseline

Bone mineral density (BMD), a measure of the mineral content in bones is assessed using dual x-ray absorptiometry (DXA). DXA can be used to identify individuals with low bone mass (LBM). DXA uses low-power x-ray and is a safe and reliable measure validated to diagnose osteoporosis. DXA provides a t-score and z-score so that based on age, low bone mass can be appropriately determined. DXA also provides a subtotal BMD score as well as scores specific to certain body regions, both of which will be utilized in the first aim.

Blood collection

Time frame: Baseline

Blood will be collected to assess for routine markers related to bone mineral density. Blood will be tested for levels of calcium, vitamin D, bone alkaline phosphatase (BALP), and C-terminal telopeptide of type I collagen (CTx). The amount of blood collected will be within hospital rules for children. The total amount of blood will be approximately 2 mL or 1/2 a teaspoon. BALP is a bone formation marker while CTx is a bone resorption marker. Calcium and vitamin D are known to be positively associated with BMD.

Fracture history

Time frame: Baseline, months 3, 6, 9, and 12

Details regarding lifetime fracture history will be collected via questioning at the in-clinic visit and during remote follow up visits, every three months for one year. The participant will be asked to describe each incident separately, including the age at fracture, mechanism of injury (how it happened, its nature, and force), any preceding events like falls or dizziness, and associated symptoms. Fractures will be characterized by location, type and treatment (surgical or conservative).

Fall history

Time frame: Baseline, months 3, 6, 9 and 12

Details regarding falls, that occurred within the past year, will be collected using a structured questionnaire at the in-clinic visit and during the one-year follow-up. Falls will be described by mechanism, environment and outcome.

Collection of spatiotempoal and kinetic gait parameters using instrumented insoles (AI-Sole)

Time frame: Baseline

Stride-by-stride spatiotemporal and kinetic gait parameters will be collected with AI-Sole continuously during the 6MWT. Spatiotemporal parameters included stride length (SL), stride velocity (SV), percent time in stance phase (%St), and percent time in terminal double support (%DS). Kinetic parameters included the anteroposterior (AP-COP) and mediolateral (ML-COP) ranges of the center-of-pressure normalized by shoe size, as well as the Absolute COP-Cyclogram Asymmetry Index (\|ASI\|).

Six Minute Walk Test

Time frame: Baseline

Participants will complete the six minute walk test in a corridor which includes the instrumented walkway, while wearing the insoles. This is to measure spatial parameters, kinetic parameters, temporal parameters, and metrics of cumulative activity in order to compare against the gold standard instrumented walkway. The six minute walk test is an objective evaluation of functional exercise capacity, and measures the maximum distance a person can walk in six minutes over a 25 meter course.

IPAQ-SF

Time frame: Baseline

A quantitative assessment of usual physical activity will be captured using the International Physical Activity Questionnaire Short Form (IPAQ-SF).The IPAQ-SF is a commonly used self-administered questionnaire designed to obtain internationally comparable data on health-related physical activity. The IPAQ-SF is composed of seven questions from four domains of physical activity, including vigorous and moderate physical activity, walking physical activity, and sitting time. A weighted total from vigorous physical activity, moderate physical activity, and walking physical activity is calculated to produce a total amount of physical activity in MET-min/week.

What is a clinical trial?

A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.

Is it safe to participate?

Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.

Will I be compensated?

Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.

Will I receive a placebo instead of treatment?

When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.

Can I leave a trial if I change my mind?

Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.

How long does a clinical trial last?

Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.