Cryoneurotomy as a Percutaneous Mini-invasive Therapy for the Treatment of the Spastic Limb: Case Presentation, Review of the Literature, and Proposed Approach for Use.

[OBJECTIVE] To provide a proof-of-concept study demonstrating that the decades old procedure of cryoneurotomy, used traditionally for analgesia, is a safe adjunctive and effective treatment for limb spasticity.

[DESIGN] Case series.

[SETTING] Publicly funded outpatient hospital spasticity clinic and community interventional anesthesia clinic.

[PARTICIPANTS] Patients (N=3) who had plateaued with standard of care spasticity treatments including botulinum toxin. Two hemiplegic stroke patients with elbow spasticity and 1 pregnant patient with multiple sclerosis and a spastic equinovarus foot for whom botulinum toxin was now contraindicated.

[INTERVENTIONS] Selective anesthetic diagnostic motor nerve blocks with ultrasound and e-stimulation with 1cc of 1% lidocaine to the motor nerve to the targeted spastic muscle were performed to either the musculocutaneous nerve to brachialis, radial nerve to the brachioradialis or the tibial nerve. If the benefits included improved active and passive range motion and or decreased clonus, a percutaneous cryoneurotomy was performed.

[MAIN OUTCOME MEASURES] Active and passive range of motion were measured using the Modified Tardieu Scale. The change in resistance to passive stretch was measured using the Modified Ashworth Scale (MAS). Videos of the before and after treatment were collected.

[RESULTS] Both elbows' treatments resulted in MAS improving from a 3 to a 1+. Greatly improved active range of motion was noted at 94 and 64 degrees, respectively, as well as improvements in passive range on the Modified Tardieu Scale. The tibial nerve cryoneurotomy resulted in improvements in all parameters with a much improved gait. Results were maintained up to 17 months of follow-up.

[CONCLUSION] Cryoneurotomy as a treatment for spasticity is a novel safe adjuvant treatment. Our initial results suggest patients can achieve significantly increased active and passive range of motion in the upper extremity and decreased clonus, and improved gait after tibial nerve cryoneurotomy.