Effect of Cryoneurolysis on Pain in Patients With Hand Contracture.

Contracture which is defined as a limitation of the maximum passive range of motion due to changes in periarticular soft tissue can contributes to severe pain and increased disabilities. Once contracture is present, management options are very limited and mainly includes surgery. This clinic offers cryoneurolysis routinely to spastic patients to manage their severe spasticity, contracture and associated pain. In this observational project, the outcomes after cryoneurolysis in patients with wrist and hand contracture will be studied systematically and with more details to determine any changes in pain and range of motion after this procedure.

Contracture is defined as a limitation of the maximum passive range of motion of a joint due to shortening and changes of periarticular soft tissue structures. Contracture contributes to severe pain, increased disabilities, decreased functional range of motion and decreased functional range of motion in daily living. The incidence of contracture in first year after has been recorded to be as high as 66%and up to 28% within 3 months after stroke. There are many pharmacological and non pharmacological guidelines available for treatment of contracture and associated pain, including botulinum toxin injection, physiotherapy, stretching and positioning, though; the surgery has been recommended as the most effective one .

Cryoneurolysis is a novel procedure that causes nerve degeneration by cooling them to -88°. The first step in this procedure is isolating the targeted nerves with ultrasound guidance and e-stimulation for motor nerves and mixed sensory motor nerves for pain management. To select the proper candidate for this procedure, targeted nerves will be temporary paralyzed by blocking them with lidocaine (DNB). In this clinic after successful DNB to reduce pain and muscle tone, the patient is offered cryoneurolysis. After rapid cooling the nerve to a certain degree the axon and myelin of targeted zone will be disrupted however ; the basal lamina, epineurium and perineurium of the targeted nerves will be remained intact and serve as a tube for neural regeneration.

This observational study, proposes to measure the effect of cryoneurolysis prospectively and systematically on pain reduction in patients with wrist and hand severe spasticity or contracture due to any underlying disease.

Eligibility Criteria:
Inclusion Criteria:

1. Adult patients(at least 18 years old).
2. Severe claw hand with less than 4 cm distance between the pulp of the fingers and palm of the hand.
3. MAS\>= 3 in wrist and hand muscles interfering with function or causing a clinical problem, due to any neurological condition.
4. Have refractory pain in wrist and hand areas with no response to the usual pain management methods including oral medication or botulinum toxin injection.
5. Patients are already candidate for cryoneurolysis to manage the pain and spasticity in their hand and wrist, based on their response to diagnostic nerve block test (DNB).
6. Ability to attend testing sessions, comply with testing protocols and provide written informed consent. For patients who physically are not able to complete the consent process, a witness may be asked to sign and confirm their willing for participation. Legal representative may be asked to help with consent process for participants who cognitively are not able to consent on their behalf.

Exclusion Criteria:

1. Have undergone any previous peripheral nerve procedures in their affected side, for the treatment of spasticity, including previous cryoneurolysis, chemical neurolysis, neurectomy or arthroplasty.
2. Patients who received botulinum toxin in past 4 months in the same targeted muscles for cryoneurolysis, however, they may enter the study at the 4-month mark.