Phenol Neurolysis for Management of Focal Spasticity in the Distal Upper Extremity

Abstract

Background When managing patients with focal spasticity, phenol neurolysis is often avoided largely because of its presumed poor adverse effect profile. It is suggested that dysesthesias may be more common with phenol neurolysis of the mixed sensorimotor nerves (eg, radial, median, and ulnar nerves) compared to neurolysis of pure motor nerves. However, these risks may be mitigated with precise localization of pure motor branches by ultrasound and electrical stimulation (EStim). Objective To explore practice patterns of phenol neurolysis to distal upper extremity mixed sensorimotor nerves with ultrasound and EStim guidance. Design A retrospective analysis of all neurolysis procedure records at a single institution from January 2013 to February 2018. Demographic and clinical variables including primary neurological diagnosis, concurrent spasticity treatments, nerves injected, phenol dosage and adverse events were abstracted from the electronic medical records. Participants 57 patients who received phenol neurolysis with ultrasound and EStim guidance for spasticity management to radial, median, or ulnar nerves. Main Outcome Measures Reported adverse effects. Results A total of 57 patients who collectively received neurolysis to 139 nerves across 102 encounters, met inclusion criteria. Most prevalent diagnoses included traumatic brain injury (N = 27, 47.4%) and stroke (N = 18, 31.6%), with a smaller subset having spinal cord injury (N = 10, 17.5%). Most patients received concomitant chemodenervation with botulinum toxin (N = 44, 77.2%). The average phenol dosage per nerve was 1.8 mL, with a range of 0.5‐9.0 mL. Reported adverse effects included three cases of prolonged pain, but no dysesthesias were reported during the follow‐up period (>40 days). Conclusions Phenol neurolysis with ultrasound and EStim guidance was successfully and safely used to manage focal spasticity in the distal upper extremity. Level of Evidence III.

Early Use of Phenol Neurolysis Likely Reduces the Total Amount of Botulinum Toxin in Management of Post-Stroke Spasticity

“…In our recent retrospective studies (21), side effects were low in general, and dysesthesia was found only in 2 out 293 of procedures (0.7%). With combined ultrasound and electrical stimulation guidance, we did not find any documented report of dysesthesia after phenol neurolysis for the distal upper extremity muscles (22). Phenol neurolysis for nerve block have shown similar or better efficacy in spasticity reduction as compared to BoNT injection (23,24).…”

Spasticity Management in Persons with Disorders of Consciousness

“…Phenol neurolysis can effectively manage spasticity in several muscles innervated by the same nerve, which is helpful in managing the widespread severe spasticity in persons with DoC. It takes effect in minutes, and could be repeated in days if necessary, which is ideal for use in the inpatient setting 10,11 . BoNT injections can be used to treat small muscles (eg, the lumbricals) or neck muscles (eg, the sternocleidomastoid muscle), in order to facilitate movement for communication or environmental control.…”

“…It takes effect in minutes, and could be repeated in days if necessary, which is ideal for use in the inpatient setting. 10,11 BoNT injections can be used to treat small muscles (eg, the lumbricals) or neck muscles (eg, the sternocleidomastoid muscle), in order to facilitate movement for communication or environmental control. Finally, by utilizing a mechanism of delivery at the microgram level of dosing into the intrathecal space, ITB pumps can be efficacious in managing spasticity in the lower extremities with a potential or additional effect on the trunk and upper extremities.…”

“…Current spasticity treatment options include physical modalities, 7,8 focal injections (chemodenervation with botulinum neurotoxin [BoNT] or phenol neurolysis), [9][10][11] systemic medications (mainly baclofen, tizanidine, dantrolene), 12 and invasive surgical approaches (intrathecal baclofen [ITB], selective dorsal rhizotomy [SDR], and thalamic stimulation). 5,6,13 Of these, only bracing, BoNT, and systemic and intrathecal baclofen have been reported for spasticity management in this population.…”

Novel Conservative Approach to High Surgical Risk Frail Proximal Femur Fractures

“…It is used in central nervous system disorders, including stroke, brain injury, and cerebral palsy. There are small-scale promising studies reviewing their efficacy and safety for this indication, Karri et al (2020) reviewed a group of 185 patients who underwent phenol neurolysis for focal spasticity [14]. 84% of those treated reported a benefit, and promisingly, there were no major adverse events reported.…”