How Should we Use Multicolumn Spinal Cord Stimulation to Optimize Back Pain Spatial Neural Targeting? A Prospective, Multicenter, Randomized, Double-Blind, Controlled Trial (ESTIMET Study).

BACKGROUND: Recent studies have highlighted multicolumn spinal cord stimulation (SCS) efficacy, hypothesizing that optimized spatial neural targeting provided by new-generation SCS lead design or its multicolumn programming abilities could represent an opportunity to better address chronic back pain (BP). OBJECTIVE: To compare multicolumn vs. monocolumn programming on clinical outcomes of refractory postoperative chronic BP patients implanted with SCS using multicolumn surgical lead. MATERIALS AND METHODS: Twelve centers included 115 patients in a multicenter, randomized, double-blind, controlled trial. After randomization, leads were programmed using only one or several columns. The primary outcome was change in BP visual analogic scale (VAS) at six months. All patients were then programmed using the full potential of the lead up until 12-months follow-up. RESULTS: At six months, there was no significant difference in clinical outcomes whether the SCS was programmed using a mono or a multicolumn program. At 12 months, in all patients having been receiving multicolumn SCS for at least six months (n = 97), VAS decreases were significant for global pain (45.1%), leg pain (55.8%), and BP (41.5%) compared with baseline (p < 0.0001). CONCLUSION: The ESTIMET study confirms the significant benefit experienced on chronic BP by patients implanted with multicolumn SCS, independently from multicolumn lead programming. These good clinical outcomes might result from the specific architecture of the multicolumn lead, giving the opportunity to select initially the best column on a multicolumn grid and to optimize neural targeting with low-energy requirements. However, involving more columns than one does not appear necessary, once initial spatial targeting of the "sweet spot" has been achieved. Our findings suggest that this spatial concept could also be transposed to cylindrical leads, which have drastically improved their capability to shape the electrical field, and might be combined with temporal resolution using SCS new modalities.

Multicolumn spinal cord stimulation lead implantation using an optic transligamentar minimally invasive technique.

BACKGROUND: A new generation of neurostimulation surgical leads is used to increase the success of spinal cord stimulation in difficult-to-treat indications such as failed back surgery syndrome. Minimal access spinal technologies (MASTs) have previously been used for surgical lead implantation. However, only a unilateral approach was possible, causing difficulties for median lead placement, and not always preventing laminectomy. A recent MAST technique was used to implant spinal cord stimulation leads without these limitations. OBJECTIVE: To describe the MAST technique used in a pilot study. METHODS: Twenty-four consecutive patients were implanted with a multicolumn surgical lead for refractory chronic back and leg pain by using the optic transligamentar MAST technique. RESULTS: The MAST technique allowed median lead placement, facilitated visualization of the spine, and permitted transligamentar insertion that minimized scarring and muscle damage. No technique-related adverse events or lead revisions were reported. CONCLUSION: Use of a MAST approach could be useful in safe implantation of multicolumn surgical leads in difficult-to-treat, refractory lower back pain conditions such as failed back surgery syndrome.

Successful treatment of pudendal neuralgia with tricolumn spinal cord stimulation: case report.

BACKGROUND AND IMPORTANCE: There is large variation in the success of decompressive surgery for pudendal neuralgia (PN), the most chronic, disabling form of perineal pain. We attempt to determine whether spinal cord stimulation using new-generation multicolumn leads could form part of the treatment algorithm for refractory PN. CLINICAL PRESENTATION: A man with PN that was unresponsive to conventional treatment demonstrated a neuropathic component and had a negative response to nerve infiltrations (so he was not indicated for decompressive surgery) and a positive response to perianal transcutaneous electrical nerve stimulation and was implanted with a 16-contact surgical lead at the level of conus medullaris, allowing multicolumn stimulation. Using transverse combinations, it was possible to obtain 100% paresthesia over the perineal area without unwanted dorsal root stimulation. Perineal and radicular pain was successfully relieved for up to 12 months (80% and 60% reduction in the visual analogue scale scores, respectively), with an improvement in all quality of life domains and a reduction in drug consumption. CONCLUSION: Spinal cord stimulation using a 16-contact lead may be a viable therapeutic option for patients with refractory PN for whom decompressive surgery is contraindicated.

Back pain: a real target for spinal cord stimulation?

BACKGROUND: Failed back surgery syndrome represents one of the most frequent etiologies of chronic back pain and is a major public health issue. Neurostimulation has currently not been validated in the treatment of back pain because of technological limitations in implantable spinal cord stimulation (SCS) systems. New-generation leads using several columns of stimulation can generate longitudinal and/or transverse stimulation fields into the spinal cord. OBJECTIVE: To investigate, through extensive stimulation testing, the capacity of multicolumn tripolar leads to achieve back territory paresthesia coverage in refractory failed back surgery syndrome patients. METHODS: Eleven patients implanted with a 16-contact spinal cord stimulation lead (Specify 5-6-5, Medtronic Inc) were assessed with a systematic exploration of 43 selected stimulation configurations to generate bilateral back paresthesia in addition to leg territory coverage. RESULTS: The tripolar lead successfully generated paresthesia in both bilateral back and leg territories in 9 patients (81.8%). Success rates of multicolumn stimulation patterns were significantly higher than for longitudinal configurations for lombodorsal paresthesia coverage. Six months after implantation, significant pain relief was obtained compared with preoperative evaluation for global pain (Visual Analog Scale, 2.25 vs 8.2 preoperatively; P < .05), leg pain (Visual Analog Scale, 0.5 vs 7.6 preoperatively; P < .05), and back pain (Visual Analog Scale, 1.5 vs 7.8 preoperatively; P < .05). CONCLUSION: These results suggest that multicolumn leads can reliably generate back pain coverage and favor pain relief outcomes. This may lead physicians to reconsider new indications for spinal cord stimulation. Expanding neurostimulation perspectives to intractable back pain syndromes could become realistic in the near future.