Intractable Complex Regional Pain Syndrome Research Articles

A Case of Intractable Complex Regional Pain Syndrome Successfully Treated with a Combination of Regional Anesthesia and Physical Therapy

A Case of Intractable Complex Regional Pain Syndrome Successfully Treated with a Combination of Regional Anesthesia and Physical Therapy

Spinal cord stimulation for treatment of complex regional pain syndrome: a single-centre retrospective case series study.

Complex regional pain syndrome (CRPS) is a debilitating disease with limited available treatment options. Spinal cord stimulation (SCS) is a universal option that promises to improve quality of life by reducing intractable neuropathic pain. The aim of this study was to describe the effectiveness and safety of SCS as a treatment for CRPS patients. SCS as an invasive method has relatively recently been introduced to CRPS therapy. We hypothesised that by assessing the effectiveness and safety of SCS, we could justify its early use in the treatment of this debilitating condition. CRPS is a multifactorial and disabling disorder with complex aetiopathogenesis. The primary goals of CRPS treatment include pain relief, functional restoration, and psychological stabilisation. Early intervention is needed to achieve these objectives. In this study, we performed a retrospective evaluation of clinical outcomes in seven patients with severe, intractable CRPS treated by SCS. All patients underwent implantation of a non-rechargeable prime advanced MRI implantable pulse generator (IPG) (Medtronic, Minneapolis, MN, USA) between December 2017 and December 2020 using identical surgical and intraprocedural techniques. From a total of 21 patients treated with SCS over the three years in question, seven (33%) were diagnosed with severe CRPS. The duration of chronic pain ranged between two and 12 years. In six cases (86%), an electrode was implanted in the thoracic segment. Good (partial pain reduction) or very good (complete pain relief) treatment results were observed in five patients (72%). In two cases (28%), two revision surgeries were performed for wound debridement. These hardware-related complications were primarily related to erosions located over implanted IPG's. SCS is the best alternative for patients with CRPS. It should be used immediately after the failure of conservative treatment. Despite the relatively high complication rate in our series, it is the best choice for pain reduction management in this select group of patients.

Single S1 Dorsal Root Ganglia Stimulation for Intractable Complex Regional Pain Syndrome Foot Pain After Lumbar Spine Surgery: A Case Series

Intractable complex regional pain syndrome (CRPS)-related chronic foot pain, is a common therapeutic challenge for interventional pain management physicians and patients alike. Dorsal root ganglia (DRG) stimulation is a very target specific dorsal column stimulation technique with very promising clinical outcomes. Patients with CRPS foot pain and previous back surgery can benefit from DRG stimulation but also run a significant risk of epidural trauma from the DRG sheath advancement. Most sensory innervation to the foot is from L5 and S1 dermatomes. Although there is dual modulation from L5 and S1 DRG, significant "cross talk" exists between these structures such that a DRG lead solely at S1 could provide pain relief for the entire foot. In this case series, we examined the outcomes obtained from placement of solely S1 DRG stimulating electrodes in patients with CRPS-related chronic foot pain, and examine whether this may provide a reduced risk of dural injury. Furthermore, we describe the technical aspects of a S1 DRG placement and discuss relevant anatomical issues pertaining to this approach. Five patients (four female, one male) with chronic foot pain participated. The oldest was 71 and the youngest 49. Three patients were diagnosed with foot CRPS-1, and two patients with foot CRPS-2. All patients had back surgery in the past and all underwent a trial and subsequent S1 DRG implantation. The patients were evaluated with a numeric rating score (NRS) for pain and function before the procedure and one, two, three, and six months after the procedure. The first patient underwent an L5 and S1 trial and developed CSF leak and postdural puncture headache. Two months later, the patient was re-trialed and implanted with a single S1 electrode. The other four patients were trialed and implanted with single S1 DRG electrodes. All five patients had severe pain (8-10 NRS) and significant loss of function and quality of life (2-4 NRS) before the procedure. All five patients had excellent (0-3 NRS) pain relief and functional restoration (8-10 NRS) with a single S1 electrode trial, and all five proceeded with permanent implantation. The pain relief from the S1 DRG stimulation extended to the entire foot without any sparing. All patients were able to discontinue or significantly reduce their oral pain medications. The one-, two-, three-, and six-month follow-up showed preservation of therapeutic efficacy. A single S1 DRG electrode placement in patients diagnosed with CRPS of the foot and who had previous back surgery is therapeutically effective and can minimize the risk of dural trauma and CSF leak.

Selective L4 Dorsal Root Ganglion Stimulation Evokes Pain Relief and Changes of Inflammatory Markers: Part I Profiling of Saliva and Serum Molecular Patterns

Complex regional pain syndrome (CRPS) and associated comorbidities have been linked to a pro-inflammatory state driven by different mediators. Targeted dorsal root ganglion stimulation (DRGSTIM ) suppressed pain levels and improved functional capacity in intractable CRPS. However, clinical trials assessing the impact of DRG stimulation on the neuroimmune axis are lacking. This study enrolled 24 subjects (12 refractory CRPS patients plus suitably matched healthy controls) and performed immunoassays of inflammatory mediators in saliva and serum along with score-based assessments of pain, mood, and sleep quality at baseline and after three months of selective L4-DRGSTIM . After three-month L4-DRGSTIM CRPS associated pain significantly decreased. In addition, disturbed sleep and mood improved post-DRGSTIM , although statistically not significant. Significantly increased serum values of pro-inflammatory markers were detected pre- and post L4-DRGSTIM for high-mobility group box 1, tumor-necrosis factor α, interleukin (IL) 6, and leptin. IL-1β was significantly elevated pre-L4 DRGSTIM , but not posttreatment. Elevated anti-inflammatory IL-10 significantly decreased after three months in serum, while saliva oxytocin concentrations increased in CRPS subjects after L4-DRGSTIM (p = 0.65). No severe implantation and stimulation associated adverse events were recorded. Selective L4-DRGSTIM improved neuropathic pain and functional impairment in CRPS as previously reported. CRPS patients displayed a pro-inflammatory molecular pattern in serum. Serum anti-inflammatory IL-10 significantly declined, while saliva oxytocin nonsignificantly increased after L4-DRGSTIM . An evidence-based relational interpretation of our study is limited due to the uncontrolled study design. However, molecular profiling of biofluids (saliva, serum) represents a novel and experimental field in applied neuromodulation, which warrant further investigations to unveil mechanisms of neuroimmune modulation.

Spinal Cord Stimulation for Complex Regional Pain Syndrome Type I: A Prospective Cohort Study With Long-Term Follow-Up

Spinal cord stimulation (SCS) is an effective treatment for intractable complex regional pain syndrome type I pain. Long-term data are scarce on effectiveness, degree of pain relief, predictors, and complications. From 1997 to 2008, 84 consecutive patients who received an implanted SCS system after positive test stimulation were included in the prospective study. Treatment effectiveness was assessed annually as measured by mean visual analog scale pain scores and with the Patients Global Impression of Change scale. Treatment success was defined as at least 30% mean pain relief at end point and treatment failure as explantation of the system. A Cox regression determined if baseline factors were associated with both these outcomes. During 11 years, 41% (95% CI: 27-55) of the patients experience at least 30% pain relief at assessment end point. During 12 years of follow-up 63% (95%CI: 41-85) of the implanted patients still use their SCS device at measured end point. Pain relief of at least 50% one week following test stimulation is associated with a higher probability of long-term treatment success. In 51 patients, 122 reinterventions were performed over 12 years; 13 were due to complications, 44 to battery changes, and 65 reinterventions were equipment related. SCS provides an effective long-term pain treatment for 63% (95%CI: 41-85) of implanted patients. Forty-one percent (95%CI: 27-55) of SCS treated patients have at least 30% pain reduction at measurement end point. The number of reinterventions after implantation due to equipment-related problems, battery changes, and complications is 122 over 12 years of follow-up. Sixty-one percent (N = 51) of the patients had at least one reintervention. Mean pain relief of at least 50% (visual analog scale) one week after the test stimulation is associated with long-term treatment success.

Pamidronate was effective for intractable complex regional pain syndrome type I: A case report

Pamidronate was effective for intractable complex regional pain syndrome type I: A case report

Complete Recovery From Intractable Complex Regional Pain Syndrome, CRPS‐Type I, Following Anesthetic Ketamine and Midazolam

To describe the treatment of an intractable complex regional pain syndrome I (CRPS-I) patient with anesthetic doses of ketamine supplemented with midazolam. A patient presented with a rapidly progressing contiguous spread of CRPS from a severe ligamentous wrist injury. Standard pharmacological and interventional therapy successively failed to halt the spread of CRPS from the wrist to the entire right arm. Her pain was unmanageable with all standard therapy. As a last treatment option, the patient was transferred to the intensive care unit and treated on a compassionate care basis with anesthetic doses of ketamine in gradually increasing (3-5 mg/kg/h) doses in conjunction with midazolam over a period of 5 days. On the second day of the ketamine and midazolam infusion, edema, and discoloration began to resolve and increased spontaneous movement was noted. On day 6, symptoms completely resolved and infusions were tapered. The patient emerged from anesthesia completely free of pain and associated CRPS signs and symptoms. The patient has maintained this complete remission from CRPS for 8 years now. In a patient with severe spreading and refractory CRPS, a complete and long-term remission from CRPS has been obtained utilizing ketamine and midazolam in anesthetic doses. This intensive care procedure has very serious risks but no severe complications occurred. The psychiatric side effects of ketamine were successfully managed with the concomitant use of midazolam and resolved within 1 month of treatment. This case report illustrates the effectiveness and safety of high-dose ketamine in a patient with generalized, refractory CRPS.

Subanesthetic ketamine infusion therapy: a retrospective analysis of a novel therapeutic approach to complex regional pain syndrome.

Complex Regional Pain Syndrome (CRPS) is a disorder that can be accompanied by severe pain that is often both chronic and resistant to conventional therapy. Harbut and Correll previously reported the successful treatment of a 9-year case of intractable Type I CRPS with an intravenous inpatient infusion of ketamine in an adult female patient. The purpose of this study was to ascertain if indeed the use of subanesthetic inpatient infusions of ketamine provide meaningful improvements in pain scores, and thus, quality of life, in patients suffering from CRPS. To achieve this objective we focused our analysis on the relief of pain obtained by patients undergoing this novel treatment option developed at Mackay Base Hospital, Queensland, Australia. Case notes of 33 patients whose CRPS pain was treated by the inpatient administration of a continuous subanesthetic intravenous infusion of ketamine were reviewed. The dose and duration of ketamine therapy and the degree and duration of relief obtained were recorded. Notable side effects were also recorded. The degree of relief obtained (immediately after the infusion) was assessed using pre- and posttreatment numeric pain scores. The duration of relief obtained (throughout the follow-up period) was analyzed using a Kaplan-Meier cumulative survival curve analysis. A total of 33 patients with diagnoses of CRPS who had undergone ketamine treatment at least once were identified. Due to relapse, 12 of 33 patients received a second course of therapy, and two of 33 patients received a third. The degree of relief obtained following the initial course of therapy was impressive (N=33); there was complete pain relief in 25 (76%), partial relief in six (18%), and no relief in two (6%) patients. The degree of relief obtained following repeat therapy (N=12) appeared even better, as all 12 patients who received second courses of treatment experienced complete relief of their CRPS pain. The duration of relief was also impressive, as was the difference between the duration of relief obtained after the first and after the second courses of therapy. In this respect, following the first course of therapy, 54% of 33 individuals remained pain free for >/=3 months and 31% remained pain free for >/=6 months. After the second infusion, 58% of 12 patients experienced relief for >/=1 year, while almost 33% remained pain free for >3 years. The most frequent side effect observed in patients receiving this treatment was a feeling of inebriation. Hallucinations occurred in six patients. Less frequent side effects also included complaints of lightheadedness, dizziness, and nausea. In four patients, an alteration in hepatic enzyme profile was noted; the infusion was terminated and the abnormality resolved thereafter. This retrospective review suggests that limited subanesthetic inpatient infusions of ketamine may offer a promising therapeutic option in the treatment of appropriately selected patients with intractable CRPS. More study is needed to further establish the safety and efficacy of this novel approach.