Cryoneurolysis to reduce post-stroke spasticity and measure brain changes

Cryoneurolysis for Spasticity Treatment: Quantifying Long-term Clinical Outcomes and Exploring Mechanisms Within the Central Nervous System

This will try cryoneurolysis to reduce arm and hand spasticity in people after stroke and track related brain activity with TMS, MRI, and fNIRS for six months.

Quick facts

• Phase: NA
• Study type: Interventional
• Enrollment: 25 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Western University, Canada (other)
• Locations: 1 site (London, Ontario)
• Trial ID: NCT06958289 on ClinicalTrials.gov

What this trial studies

Cryoneurolysis delivers a freezing needle alongside a targeted peripheral nerve to produce localized nerve breakdown and reduce focal spasticity. The study enrolls people with post-stroke spasticity who show benefit from a diagnostic nerve block and have at least flicker movement in the affected upper limb. Investigators will record brain and motor system measures using transcranial magnetic stimulation (TMS), structural MRI, and functional near-infrared spectroscopy (fNIRS) before and over six months after treatment. The protocol excludes people with contraindications to TMS or 3T MRI, recent botulinum toxin injections, or inability to consent.

Who should consider this trial

Good fit: Adults with focal post-stroke spasticity who improve with a diagnostic nerve block, have at least flicker movement in the affected arm, are 3+ on the Modified Ashworth Scale, and have not received botulinum-A injections within three months are the intended candidates.

Not a fit: People with widespread systemic spasticity, recent botulinum toxin use, contraindications to TMS or 3T MRI, severe cognitive impairment, pregnancy, or prior nerve-specific procedures are unlikely to benefit or be eligible.

Why it matters

Potential benefit: If successful, cryoneurolysis could offer longer-lasting, targeted reduction of focal post-stroke spasticity and provide insight into brain changes that support durable improvement.

How similar studies have performed: Peripheral denervation approaches like botulinum toxin are established for focal spasticity and early clinical reports of cryoneurolysis are promising, but long-term central nervous system effects from cryoneurolysis remain novel and not yet widely proven.

Eligibility criteria

Inclusion Criteria:

* have increased range of motion or reduced spasticity with diagnostic nerve block,
* have no undesired loss of function with a diagnostic nerve block,
* score 2 or higher in the Modified Ashworth scale,
* have at least flickers of movement in the upper extremity,
* have not received botulinum-A neurotoxin within the past 3 months,
* if on anti-spastic medication, maintaining anti-spastic medications on a stable schedule over the course of the follow up period, and
* they can understand and follow instructions in English.

Exclusion Criteria:

* have contraindications to TMS (i.e., history of seizure, pregnancy) or 3T MRI (i.e., certain metallic implants),

  * are unable to provide informed consent (i.e., severe cognitive impairment),
  * receive any toxin injections for spasticity (Botulinum-A Toxin or equivalent) within 3 months of initial baseline assessments or at any time over the course of the follow-up period.
  * Have previously undergone any nerve-specific interventions (phenol neurolysis, radio-frequency ablation, or cryoneurolysis) for spasticity on a nerve that will be targeted for this study.

Where this trial is running

London, Ontario

• Parkwood Institute — London, Ontario, Canada (RECRUITING)

Study contacts

• Principal investigator: Sue Peters, PhD — Western University
• Study coordinator: Sue Peters, PhD

Conditions: Spasticity as Sequela of Stroke, NIRS, TMS, cryoneurolysis, fNIRS