Clinical Efficacy of an Ultrasound-Guided Greater Occipital Nerve Block at the Level of C2.
The purpose of this prospective open-label study was to investigate the analgesic effects of an ultrasound-guided greater occipital nerve (GON) block at the level of C2, as the nerve courses superficially to the obliquus capitis inferior muscle.



Patients with a diagnosis of occipital neuralgia or cervicogenic headache were recruited for the study. Ultrasound-guided GON blocks at the level of C2 were performed by experienced clinicians according to a standardized protocol. Numeric rating scale pain scores were recorded preinjection and at 30 minutes, 2 weeks, and 4 weeks after injection.



A total of 14 injections were performed with a mean procedure time of 3.75 minutes. Anesthesia in the GON distribution was achieved for 86% of patients at 30 minutes postinjection. Compared with baseline, numeric rating scale scores decreased by a mean of 3.78 at 30 minutes (P < 0.001), 2.64 at 2 weeks (P = 0.006), and 2.21 at 4 weeks (P = 0.01). There were no significant adverse events reported during the study period.



This prospective open-label study demonstrated successful blockade of the GON at the level of C2 using a novel ultrasound-guided technique. Significant reductions in pain scores were observed over the 4-week study period, and no adverse events were reported. The observations from this study provide important preliminary data for future randomized trials involving patients with occipital neuralgia and cervicogenic headache.
From the Departments of *Physical Medicine and Rehabilitation and †Anesthesiology, Mayo Clinic, Rochester, MN; and ‡Departments of Neurosciences and Family Medicine, University of South Dakota Sanford School of Medicine, Sioux Falls, SD.
Matthew J
MJ
Pingree
Joshua S
JS
Sole
Travis G
TG
Oʼ Brien
Jason S
JS
Eldrige
Susan M
SM
Moeschler
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000779:Anesthetics, Local / Q000008:administration & dosage*; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000379:methods*; D009437:Neuralgia / Q000000981:diagnostic imaging* / Q000628:therapy; D011446:Prospective Studies; D013127:Spinal Nerves / Q000000981:diagnostic imaging* / Q000187:drug effects; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional / Q000379:methods*
D000779:Anesthetics, Local