Spinal Cord Stimulation for Lower Extremity Function
- Conditions
- Spinal Cord Injury
- Interventions
- Other: Adjustment of spinal cord stimulation parameters for voluntary motor control
- Registration Number
- NCT06438991
- Lead Sponsor
- Brigham and Women's Hospital
- Brief Summary
This prospective clinical study will investigate the ability of different spine imaging characteristics to predict ambulation recovery responsiveness using epidural spinal cord stimulator (SCS) in patients with chronic incomplete spinal cord injury (SCI).
Epidural spinal cord stimulation below the level of injury can restore previously lost lower extremity voluntary motor function for some patients. The goal of this study is to establish whether spine imaging can be utilized as a biomarker to predict which patients will respond to spinal cord stimulation.
- Detailed Description
Ten patients with chronic spinal cord injury who are scheduled to receive a spinal cord stimulator for refractory chronic pain will be recruited throughout the Mass General Brigham health system. At baseline, participants will undergo a neurologic strength exam, Magnetic Resonance Imaging (MRI) of the spine and brain, electromyography (EMG) of the lower extremities, and will complete a battery of pain, motor function and quality of life questionnaires.
Phase 1: The SCS Optimization phase consists of weekly research visits during the first month post-SCS implant. Settings of the spinal cord stimulator parameters will be modified for activation and optimal voluntary control of lower extremity muscles.
Phase 2: The Individualized Neurorehabilitation phase consists of 4 weekly visits for a 5-month period. Participants will undergo neurorehabilitation with the stimulation settings turned on for motor control. Neurorehabilitation will be individualized and will progressively increase participants' physical activity, including assisted/independent standing, stepping and ambulation within safe limits. Participants will undergo monthly muscle strength and surface EMG testing.
At the end of each research visit or neurorehabilitation session, SCS settings will be adjusted to the original pain management parameters.
At the 6-month follow up participants will undergo a neurologic strength exam, MRI of the spine and brain, EMG of the lower extremities and a battery of questionnaires. After the last follow up visit, participants will have the opportunity to continue a long-term follow up or exit the study. SCS parameters will be adjusted to the pain management settings.
Recruitment & Eligibility
- Status
- NOT_YET_RECRUITING
- Sex
- All
- Target Recruitment
- 10
- Age >18 years
- Provides informed consent
- Eligible for and undergoes SCS implant for chronic low back or leg pain refractory to first-line therapy
- Stable SCI secondary to a single insult
- C6-T10 level of injury
- SCI has occurred >12 months prior to enrollment
- Chronic low back pain refractory to first-line therapy
- Current AIS grade B-C, with spared sensation
- Willingness and ability to adhere to the protocol
- History or diagnosis of Central Nervous System malignancy
- Diagnosis that is a contraindication to SCS implantation or surgery
- Diagnosis that precludes the subject from full participation in physical therapy
- Known osteopenia/osteoporosis
- Impairment in post-operative recovery per clinical evaluation by the principal investigator
- Inability to participate in the protocol, including but not limited to all study visits and assessments
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- SINGLE_GROUP
- Arm && Interventions
Group Intervention Description All participants Adjustment of spinal cord stimulation parameters for voluntary motor control Baseline: participants will undergo lower extremity muscle strength testing, electromyography, spine and brain MRI, and complete a battery of questionnaires All participants will undergo a clinically indicated spinal cord stimulator implanted for refractory chronic pain. SCS Optimization phase consists of weekly research visits for 1 month. SCS parameters will be optimized for voluntary control of lower extremity muscles. Individualized Neurorehabilitation phase consists of 4 x weekly visits for 5-months. With the SCS settings turned on for muscle activation, participants will undergo progressive neurorehabilitation by a spinal cord specialized physical therapist. All participants who complete the 6-month timepoint will be invited to continue long-term follow up.
- Primary Outcome Measures
Name Time Method Incidence of treatment-related adverse events 0-6 months after baseline The primary endpoint of this study is the safety of stimulation parameters for motor function assessed with the number of adverse events for the duration of the study. Relatedness of adverse events to treatment is determined by the principal investigator.
- Secondary Outcome Measures
Name Time Method Optimized stimulation pulse width for voluntary motor function 1-6 months after baseline Stimulation pulse width required for voluntary motor function measured in microseconds when supine, assisted/independent standing, stepping, walking.
Muscle Strength 1-6 months after baseline The ability to restore previously lost voluntary motor function of the lower extremity will be measured with the Medical Research Council (MRC) grade and compared to baseline. MRC grades range from 0 (no visible muscle contraction) to 5 (normal muscle strength against full resistance). A higher grade indicates a better outcome.
Neuroimaging volumetric measures 0-6 months after baseline Assessment of the functional integrity of corticospinal tracts with spine and brain Magnetic Resonance Imaging (MRI) will be performed at baseline and at the last follow up. MRI volumetric measures are quantified in mm\^2.
Optimized stimulation amplitude for voluntary motor function 1-6 months after baseline Stimulation amplitude required for voluntary motor function measured in mA (miliAmperes) when supine, assisted/independent standing, stepping, walking.
Voluntary Motor Function 0-6 months after baseline Functional change assessed with the total score on the American Spinal Injury Association Impairment Scale (AIS) of each participant before spinal cord stimulation (SCS) and after SCS augmented with neurorehabilitation therapy. The AIS scale ranges from A (no sensory or motor function is preserved in sacral segments of S4-S5) to E (sensation and motor testing are normal in all segments), with A representing the worst outcome and E representing the best outcome.
Optimized stimulation frequency for voluntary motor function 1-6 months after baseline Stimulation frequency required for voluntary motor function measured in Hz (Hertz) when supine, assisted/independent standing, stepping, walking.
Serious adverse events 1-6 months after baseline Serious adverse events related to the post-SCS implant neurorehabilitation therapy.
Locomotive ability 1-6 months after baseline Ability to stand, step, or walk either assisted or unassisted assessed with the Walking Index for Spinal Cord Injury II (WISCI II) scale. The WISCI II scale ranges from minimum score of 0 (unable to stand) to maximum score of 20 (ambulates with no devices, brace or assistance). A higher score represents a better outcome.