The study was published in the journal Stereotactic and Functional Neurosurgery.
About 11-15% of patients with Friedreich’s ataxia experience painful muscle spasms or muscle contractions, but little is known about the underlying processes that cause this complication.
Physiotherapy is commonly the first approach to manage these symptoms, and oral medications such as muscle relaxers and pain relievers are often used if that doesn’t work.
In the study titled “Intrathecal Baclofen Therapy for Painful Muscle Spasms in a Patient with Friedreich’s Ataxia,” Greek researchers reported the case of a woman with FA who experienced drug-resistant painful muscle spasms.
She first began experiencing ataxia symptoms at age 22 with unsteadiness and hand clumsiness, but a diagnosis of Friedreich’s ataxia wasn’t confirmed until years later, after a genetic analysis.
Her motor function deteriorated progressively, and by the age 28 she needed to use a cane. For the last 15 years she had been wheelchair-bound. When she was 58 she started to develop severe difficulties in speech articulation.
At age 64, the patient began experiencing muscle spasms from every five minutes to every three hours, affecting her legs and trunk simultaneously.
These painful events would even happen during the night, waking her up, which led to severe sleep deprivation. They were usually triggered by coughing or sneezing, or following exposure to cold.
She was treated with 20 mg oral baclofen three times a day, 5 mg of Valium (diazepam) before sleep, and botulinum toxin injections, but they all failed to provide any relief.
Because the patient did not show any improvements, the team decided to administer 50 micrograms of baclofen directly into her spinal canal. In the following four hours she showed significant improvements, with reduced frequency and severity of the muscle spasms. Indeed, the treatment allowed her to be spasm-free for 16 hours with no reported adverse effects.
Supported by this initial positive response, she underwent a surgical implant of a programmable baclofen infusion pump that automatically administered the drug into the spinal canal (called an intrathecal pump).
“After the implantation, the reduced frequency of spasms resulted in a remarkable pain relief and sleep continuity improvement,” the authors said in the case study.
Over the following three years the FA patient experienced a low frequency of muscle spasms, with reports of one episode once or twice a month, mostly related to weather changes.
“To our knowledge, this is the third reported case in the literature regarding intrathecal baclofen therapy as an option for treating disabling spasms in a patient with Friedreich’s ataxia,” the researchers wrote.
Friedreich’s ataxia is a degenerative disease that involves the sensory nerve cells but also several nerve fibers of the spinal cord and brain. Previous studies had shown that patients with Friedreich’s ataxia have marked atrophy of the spinal cord, but there are fewer reports of cerebral alterations.
Also, FA patients are more susceptible to experiencing chronic spinal cord lesions.
Collectively, these findings suggest that patients with Friedreich’s ataxia may have impaired spinal function as well as loss of control signals sent by the brain, which could help explain the painful muscle spasms.
Although the function of frataxin — the malfunctioning protein in Friedreich’s ataxia — in cells is still unclear, the authors believe an evaluation of frataxin’s potential role in spinal cord atrophy would be relevant for FA patients.