Efficacy of high-frequency spinal cord stimulation for fibromyalgia syndrome in two cases: case reports.

BACKGROUND: Reports on the effectiveness of spinal cord stimulation (SCS) for the alleviation of fibromyalgia syndrome (FMS) pain are scarce. We report two cases of effective high-frequency SCS at 1000 Hz against upper- and lower-limb pain in patients with FMS. CASE PRESENTATION: Two women with widespread pain were diagnosed with FMS and the pain gradually worsened. A 1-week SCS trial was conducted in each patient. In both cases, the patients complained of unpleasant sensations during 10-Hz SCS. However, the pain was alleviated after 1000-Hz stimulation without irritation. Therefore, leads and a generator were implanted, after which they felt almost no pain. Moreover, the dose of the oral medication could be reduced and the patients returned to their daily lives. CONCLUSION: SCS at 1000 Hz may effectively treat pain associated with FMS. Therefore, performing an SCS trial for patients with FMS with intractable pain might be worthwhile.

Usefulness of cordotomy in patients with cancer who experience bilateral pain: implications of increased pain and new pain.

BACKGROUND: Although mirror pain occurs after cordotomy in patients experiencing unilateral pain via a referred pain mechanism, no studies have examined whether this pain mechanism operates in patients who have bilateral pain. OBJECTIVE: To assess the usefulness of cordotomy for bilateral pain from the viewpoint of increased pain or new pain caused by a referred pain mechanism. METHODS: Twenty-six patients who underwent percutaneous cordotomy through C1-C2 for severe bilateral cancer pain in the lumbosacral nerve region were enrolled. Pain was dominant on 1 side in 23 patients, and pain was equally severe on both sides in 3 patients. Unilateral cordotomy was performed for the dominant side of pain, and bilateral cordotomy was performed for 13 patients in whom pain on the nondominant side developed or remained severe after cordotomy. RESULTS: After unilateral cordotomy, 19 patients (73.1%) exhibited increased pain, which for 14 patients was as severe as the original dominant pain. After bilateral cordotomy, 7 patients (53.4%) exhibited new pain, which was located cephalad to the region rendered analgesic by cordotomy and was better controlled than the original pain. No pathological organic causes of new pain were found in any patient, and evidence of a referred pain mechanism was found in 3 patients after bilateral cordotomy. CONCLUSION: These results show that a referred pain mechanism causes increased or new pain after cordotomy in patients with bilateral pain. Nevertheless, cordotomy can still be indicated for patients with bilateral pain because postoperative pain is better controlled than the original pain.

[A case of neuropathic cancer pain in the lower extremities successfully treated with spinal cord stimulation].

A 76-year-old man was referred to our pain clinic for the treatment of bilateral lower extremity pain due to metastasis of renal cell carcinoma to the sacrum. The pain could not be controlled with narcotics, antidepressant or the epidural block. The characteristics of pain were like those of benign disease, being spontaneous, not exacerbated by body movement, and having a dysesthetic nature with chill sensations. Therefore, spinal cord stimulation (SCS) was performed, relieving the pain until death, 6 months after its induction. This case shows the usefulness of SCS for neuropathic cancer pain that shows signs similar to those of benign disease.