Periodic limb movement disorder (PLMD) involves periodic, stereotypic movements of upper/lower extremities during sleep. We present a unique case of refractory PLMD benefiting from stellate ganglion block (SGB).

A 74-year-old male with history of anterior cervical discectomy and fusion C4-5/C5-6 (2016) with residual myelopathy, cervical spondylosis (s/p C3/4 radiofrequency ablation), GERD presented with right lower extremity muscle jerking for 30 years. Episodes occur 30 minutes after sleep, repeat every 15 seconds in the right sometimes left leg, occur for several hours, and improve with walking. Intense spasms disturb sleep nightly.  Denies daytime symptoms or in upper extremities. Differential included PLMD and propriospinal myoclonus secondary to cervical myelopathy. Patient tried heat therapy (somewhat helpful), Ropinirole (helpful, unable to tolerate due to GERD), gabapentin (unclear benefit), duloxetine (not helpful), valium (sometimes helpful, limited by excessive sedation), Botox (briefly helpful), pramipexole (too expensive), baclofen (not helpful). Spinal cord stimulator trial slightly improved symptoms but without major improvement, so was not implanted. Notably, movements occurred while under general anesthesia and resolved on emergence. SGB first done April 2024 significantly improved symptoms. It was repeated every two weeks for 3 months with sustained benefit.

This case demonstrates refractory PLMD necessitating trial and error of treatments, improving with SGB. The stellate ganglion can cause sympathetic overdrive; blockage reduces activity. Several SGB indications include complex regional pain syndrome, postherpetic neuralgia, anosmia, PTSD, and long-COVID. Proposed PLMD mechanism is hyperexcitability of spinal flexor pathways, increasing limb movements during sleep. Since SGB decreases sympathetic activity, spinal flexor pathway hyperexcitability may decrease as well. Propriospinal myoclonus was also considered, and antiepileptic trial, ie, levetiracetam/clonazepam, was advised³. However, lack of valium response made this diagnosis unlikely.

SGB for PLMD has not been previously described. In our case, SGB showed an extremely beneficial response for PLMD.