Primary Outcome Measures:
- Score on the Pain Subscale of the TWSTRS
Secondary Outcome Measures:
- Daily pain diary for 14 days post-injection
- Safety profile at study exit
Cervical dystonia (CD) is a condition characterized by involuntary movements of the neck. Generally these movements are rotational and are frequently associated with significant pain. Treatment of CD with oral medications is usually unsuccessful and the current treatment of choice for the majority of patients consists of periodic injections of botulinum toxin into the offending muscles. Resistant cases are considered candidates for selective surgical denervation procedures.
Botulinum toxin type A (Botox®) is a FDA approved treatment for CD. Botox® has been safely used to treat CD in our clinic since 1989. In controlled trials, Botox® significantly improved pain in patients with CD.
Cervico-thoracic pain syndromes not associated with dystonia (refractory cervicothoracic myofascial pain syndrome or CMPS) is a chronic regional pain syndrome. It is a common component in acute and chronic pain syndromes, occurring in up to 14% of the U.S. population. This pain is often resistant to treatment and is characterized by a series of tender trigger points. These are often injected with local anesthetics that provide temporary relief of pain in some patients. Recent uncontrolled trials have suggested that Botox® may be helpful in patients with CMPS. Most attempts to use Botox® to treat these Patients have utilized smaller doses of Botox® than those used typically to treat CD. Also, most studies have used Botox® injection into tender trigger points rather than into the belly of the muscle as is commonly done to treat CD.
In this study we will use doses of Botox® that are typically used to treat CD. Injections of Botox® will be guided by EMG to determine areas of involuntarily firing muscle rather than solely into tender trigger points. The results in patients with CMPS will be compared to the pain relief experienced with those with CD. It is hoped that this trial will provide pilot data for planning a larger safety and efficacy trial of Botox® for chronic cervico-thoracic pain not associated with CD.