#MSBlog: Although rarely done spinal cord stimulation can have a dramatic response in MSers with intractable central pain.
Burkey & Abla-Yao. Successful treatment of central pain in a multiple sclerosis patient with epidural stimulation of the dorsal root entry zone. Pain Med. 2010 Jan;11(1):127-32. doi: 10.1111/j.1526-4637.2009.00764.x.
OBJECTIVE: This is a report of a case of central pain successfully treated by epidural placement of spinal cord stimulator electrodes. Neuromodulation of primary afferent fibers and the underlying dorsal root entry zone provided effective analgesia whereas traditional lead placement over the dorsal columns on a prior occasion had not been effective. The rationale for this technique based on current understanding of the mechanisms of central pain and the risk/benefit considerations are discussed.
CASE REPORT: A 52-year-old woman presented with a 2-year history of pain in the lateral hand secondary to a demyelinating episode in the C2-4 spinal cord secondary to multiple sclerosis. Medications, sympathetic blocks, and acupuncture had been ineffective. One year after an unsuccessful single-lead trial of spinal cord stimulation over the cervical dorsal columns, a dual-lead trial of spinal cord stimulation over the lateral cervical spinal cord and dorsal roots provided significant analgesia, prompting a successful permanent implant.
OUTCOME MEASURES: Responses on the Brief Pain Inventory short form and quantitative thermosensory testing data were collected at two timepoints 16 days apart under two conditions: no stimulation and single-lead stimulation of cervical primary afferents and underlying spinal cord.
RESULTS: The patient’s questionnaire responses indicated significantly improved pain scores with lateral-lead neuromodulation that was associated with a reduction in her baseline heat hypoalgesia.
CONCLUSIONS: Lateral-lead spinal cord stimulation may be effective for some central pain syndromes through a partial restoration of homeostatic small-fiber signaling. Neuroanatomical and physiological data in a larger population of patients will be required to predict the best responders to this therapeutic modality.
Lopez et al. Spinal Cord Stimulation and Thalamic Pain: Long-term Results of Eight Cases. Neuromodulation. 2009 Jul;12(3):240-3. doi: 10.1111/j.1525-1403.2009.00221.x.
Objectives: This is a retrospective analysis of results of 8 subjects suffering from intractable pain of established or suspected thalamic origin.
Case series: These subjects were treated with spinal cord stimulation (SCS) in the cervical or dorsal cord. No subject was suffering pain from a complete hemibody or facial area.
Material and Methods: Five men and three women aged 27-67 years were treated in the Pain Unit of our institution between April 1993 and January 2006. The cause of pain in five cases was stroke (plus one suspected). Multiple sclerosis was responsible for pain in two cases. An upper or lower extremity was affected in six cases. Extension to adjacent trunk was common. Exclusive trunk pain was treated in two cases.
Results: The follow-up period was 36-149 months. Two subjects were not battery-implanted because pain relief was insufficient during the trial phase. Two subjects had a further stroke: One died and one was cured from pain. Good-to-excellent results were attained in six subjects; long-term good-to-excellent results were maintained in three subjects.
Conclusions: Despite previous adverse reports, certain cases of thalamic pain can be effectively alleviated through SCS.
“I have a few MSers under my care that have undergone this procedure with dramatic results. When all else fails it is worth considering a surgical procedure, particularly of if the MSer concerned can’t tolerate the medication. The one MSer I look after literally woke up as we weaned down the anti-convulsants they had been on – the so called reverse-zombie effect.”
“There is one proviso, you need to be managed by a specialist team with experience in this technique; i.e. the centre needs to have done the procedure many times and have experience with using the stimulator and its settings.”