Myofascial pain is one of the most common causes of regional pain yet with no definitive treatment modality. This randomized clinical trial was conducted to assess the efficacy of deep cervical plexus block versus placebo injection (sham block) for the treatment of myofascial neck and shoulder pain in terms of analgesic consumption and pain during a follow up period of two weeks after performing the block.
Patients were randomly divided into two groups. Group I (Block) received deep cervical plexus block and group II (Placebo) received normal saline. A total of 66 patients were included in the study, 34 patients in the block group and 32 patients in the placebo group.
Two weeks after the intervention, average pain duration was significantly lower in the block group (1.38±1.39 vs. 5.25±1.72) for the block and placebo groups respectively (P-value<0.0001). Pain intensity was significantly less in the block group such that 2.9% of patients in the block group had severe pain compared to 53.1% of patients in the placebo group (P-value<0.0001). Two weeks after receiving the block, the mean opioid consumption calculated as tramadol equivalent was 21.1±44.2▒mg compared to 166.1±118.8▒mg for the block and placebo groups respectively. Multivariate analysis revealed that patients with a longer history of pain had a higher pain score after two weeks. The possibility of recovery is affected by pain duration since patients with chronic history of pain were least affected by the block.
This technique could be an alternative to pharmacological and non-pharmacological treatments for myofascial pain.

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