Effectiveness of Radiofrequency Ablation of the Genicular Nerves of the Knee for the Management of Intractable Pain from Knee Osteoarthritis.

BACKGROUND: The knee joint is one of the most common diseases in elderly individuals. This is a progressive and debilitating condition. The purpose of knee osteoarthritis treatment is to manage pain, increase mobility, and improve the quality of life. OBJECTIVES: This study evaluated the therapeutic effect of radiofrequency thermocoagulation (RFTC) on the genicular nerves in patients with intractable pain due to knee osteoarthritis, as well as its effects on pain severity and magnetic resonance imaging (MRI) findings. STUDY DESIGN: A prospective outcome study. SETTING: The outpatient clinic of a single academic medical center. METHODS: We conducted a prospective study. Fifty consecutive patients with intractable knee pain due to osteoarthritis were enrolled and underwent ultrasound (US)-guided RFTC of the genicular nerves (medial superior genicular nerve, medial inferior genicular nerve, and lateral superior genicular nerve). Pain severity was measured using the Numeric Rating Scale (NRS), and knee osteoarthritis-associated symptoms were evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at pretreatment and one, 3, and 6 months after RFTC treatment. We also analyzed the relationship between therapeutic outcomes and pain severity based on pre-treatment and knee MRI findings. RESULTS: No dropouts were observed. The most significant reduction in knee symptoms associated with knee osteoarthritis was observed after one month of treatment; however, at 3 and 6 months, there was a rebound effect, leading to a decrease in therapeutic efficacy. Nonetheless, there was still a noticeable decrease in symptoms due to knee osteoarthritis compared to those prior to RFTC treatment. The effect of RFTC treatment was better when pre-treatment pain was relatively less severe, knee effusion was not severe, there were no meniscal tears in the middle or posterior zones, no bone marrow edema in the middle and posterior zones of the femur and tibia, and no severe cartilage defects in the posterior femur and middle and posterior tibia. LIMITATIONS: We conducted our study without a control or a placebo group. CONCLUSION: RFTC of the genicular nerve is a good therapeutic option for controlling intractable pain following knee osteoarthritis. In addition, we found that a lower level of pain prior to treatment, along with the absence or lesser degree of knee joint effusion, as well as an absence or less severe middle or posterior knee pathologies associated with knee osteoarthritis, can predict a more favorable therapeutic outcome.

Effectiveness of CT-guided percutaneous cordotomy in intractable cancer pain: Experience in 14 patients.

BACKGROUND: Severe and treatment-resistant pain is a major issue for patients with cancer. Cordotomy is an effective approach for addressing severe cancer-related pain. It is based on blocking the transmission of pain by damaging the lateral spinothalamic tract. METHODS: Computed tomography guided cordotomy was performed on 14 patients who did not respond to medical and interventional pain management methods. RESULTS: Fourteen patients with cancer pain underwent CT-guided percutaneous cordotomy. Pain relief was reported in 86% of the patients. The visual analog scale values before and after cordotomy were compared and a significant difference was found (p = 0.0001). The improvement in the Karnofsky Performance Scale score of the patients was found to be statistically significant (p = 0.0001). CONCLUSION: We believe that CT-guided cordotomy, performed by experienced hands in a team of experienced individuals and applied to the right patients, is an effective treatment. However, it is crucial to exercise extreme caution regarding potential side effects and serious complications during the cordotomy procedure.

Palliative Radiofrequency Ablation Therapy for Intractable Cancer-Related Pain Due to Malignant Psoas Syndrome: Case Report.

Uncontrollable cancer pain is a highly feared and debilitating symptom. The effectiveness of radiofrequency ablation (RFA) for osseous metastases with intractable cancer-related pain refractory to pharmacological therapy has been reported previously. This case report is the first to demonstrate the use of RFA to achieve pain relief in a patient suffering severe pain caused by para-aortic lymph node metastasis. A 55-year-old male complained of intractable pain in the left groin and perineum due to malignant psoas syndrome caused by metastatic para-aortic lymph nodes. The pain was refractory to medications including opioids and nerve blocks. Considering the dermatome indicating referred pain and the imaging findings, RFA of the area of invasion was performed at the L3 level. The severe pain was relieved within 24 hours without any complications. Opioids were tapered at each postoperative outpatient visit. We discuss the use of RFA for control of intractable cancer-related pain refractory to medication, including opioids.

Open Thoracic Cordotomy for Cancer Pain with Intraoperative Neuromonitoring: A Case Series and Critical Review of the Literature.

OBJECTIVE: Cordotomy is a viable option for patients with intractable cancer pain and limited survival. Open thoracic cordotomy is offered when patients are not candidates for percutaneous cordotomy. After the open procedure, traditionally performed purely based on anatomic landmarks, up to 22% of patients experience postoperative limb weakness. The objective of this study is to report our experience with neurophysiology-guided open cordotomy along with a critical review of the literature. METHODS: Between 2019 and 2022, 5 open thoracic cordotomies were performed in our center. Intraoperative neurophysiologic monitoring was used in all cases to guide the lesion and standard single-level laminectomy or hemilaminectomy was performed for exposure. Outcome measures were retrospectively reviewed focusing on pain control and neurologic status. Existing literature on cordotomy was critically reviewed. RESULTS: There was satisfactory pain relief with preservation of motor function in all 5 cases. Temperature sensation was preserved in all but 1 patient, who lost it after the previous ipsilateral percutaneous cordotomy (PCC). No procedural complications were experienced. We found that the neurophysiology monitoring lesion was guided anterior compared with what would have been lesioned on an anatomic basis. CONCLUSIONS: Open thoracic cordotomy is a safe and effective procedure for intractable cancer-related pain. Technical advancements significantly reduced mortality and major morbidity of PCC. Our series suggests that neurophysiology monitoring alters the location of the lesion and may help better targeting of pain fibers within the spinothalamic tract and preserve other long tracts. The safety profile of open cordotomy with neurophysiology compares favorably with the PCC.

Open thoracic cordotomy for intractable cancer pain: a how I do it.

BACKGROUND: Some cancers of the lower extremity involve nerves and plexuses and can produce extreme drug-resistant noceptive pain. In these cases, open thoracic cordotomy can be proposed. METHOD: This procedure involves disruption of the spinothalamic tract, which sustains nociceptive pathways. After placement in the prone position, selection of the side to be operated on (contralateral to the pain), and dura exposure, microsurgery is used to section the anterolateral spinal cord quadrant previously exposed by gently pulling on the dentate ligament. CONCLUSION: Open thoracic cordotomy is a moderate invasive, safe, and effective option for the management of drug-resistant unilateral lower extremity cancer pain in well-selected patients.

Supraorbital Nerve Stimulation for Facial Pain.

PURPOSE OF REVIEW: Chronic facial pain is considered one of the conditions that affect quality of daily life of patients significantly and makes them seek medical help. Intractable facial pain with failed trials of medical treatment and other pain management therapies presents a challenge for neurologists, pain specialists, and neurosurgeons. We describe the possibility of proposing peripheral nerve stimulation of the supraorbital nerves to treat patients with medically intractable facial pain. Stimulation of the supraorbital nerves is performed using percutaneously inserted electrodes that are positioned in the epi-fascial plane, traversing the course of the supraorbital nerves. The procedure has two phases starting with a trial by temporary electrodes that are inserted under fluoroscopic guidance and are anchored to the skin. This trial usually lasts for a few days to 2 weeks. If successful, we proceed to the insertion of a permanent electrode that is tunneled under the skin behind the ear toward the infraclavicular region in which we make a pocket for the implantable pulse generator. RECENT FINDINGS: This procedure has been used in multiple patients with promising results which was published in literature. Literature shows that it provides relief of medically intractable pain, without the need for destructive procedures or more central modulation approaches with a preferable safety profile compared to other invasive procedures. Supraorbital nerve stimulation is now considered a valid modality of treatment for patients with medically intractable facial pain and can be offered as a reliable alternative for the patients while discussing the proper plan of management.

INTRACTABLE PAIN AND DIPLOPIA AFTER SCLERAL BUCKLE SURGERY.

PURPOSE: To report a case of early postoperative scleral buckle slippage because of the dehiscence of scleral belt loop tunnels. METHOD: Case report. RESULTS: A 54-year-old woman presented with painful diplopia after a combination pars plana vitrectomy and scleral buckling procedure. Ocular movements were limited. Forced duction testing was restricted in all directions. Anterior slippage of the silicone band was suggested on computed tomography (CT) scans and was confirmed with surgical exploration. During surgery, it was found that thin-roofed scleral belt loop tunnels were dehisced in three quadrants leading to anterior slippage of the buckle. The displaced buckle was removed. Diplopia and pain resolved, and ocular motility improved immediately afterward. The retina remained attached at six months follow-up. A supplemental video summarizes the surgical findings and postoperative results. CONCLUSION: Spontaneous dehiscence of scleral belt loops may occur in thinly dissected scleral tunnels. Painful eye movement, diplopia, and a positive forced duction test should raise suspicion about a displaced scleral buckle. A CT scan may help with the diagnosis. Early diagnosis and immediate surgical intervention are needed to minimize patient discomfort and to improve long-term ocular motility.

Multidisciplinary management of chronic refractory pain in autosomal dominant polycystic kidney disease.

BACKGROUND: Chronic pain is often difficult to manage in autosomal dominant polycystic kidney disease (ADPKD) patients and sometimes even leads to nephrectomy. We analyzed the long-term efficacy of our innovative multidisciplinary protocol to treat chronic refractory pain that aims to preserve kidney function by applying among other sequential nerve blocks. METHODS: Patients were eligible if pain was present ≥3 months with a score of ≥50 on a visual analog scale (VAS) of 100, was negatively affecting quality of life and if there had been insufficient response to previous therapies, including opioid treatment. Treatment options were, in order, analgesics, cyst aspiration and fenestration, nerve blocks and nephrectomy. RESULTS: A total of 101 patients were assessed in our clinic (mean age 50 ± 11 years, 65.3% females). Eight patients were treated with medication, 6 by cyst aspiration or fenestration, 63 by nerve blocks and 6 received surgery as the first treatment option. Overall, 76.9% experienced a positive effect on pain complaints shortly after treatment. The VAS score was reduced from 60/100 to 20/100 (P < 0.001) and patients decreased their number of nonopioid and opioid analgesics significantly (P < 0.001, P = 0.01, respectively). A substantial number of the patients (n = 51) needed additional treatment. At the end of follow-up in only 13 patients (12.9%) was surgical intervention necessary: 11 nephrectomies (of which 10 were in patients already on kidney function replacement treatment), 1 liver transplantation and 1 partial hepatectomy. After a median follow-up of 4.5 years (interquartile range 2.5-5.3), 69.0% of the patients still had fewer pain complaints. CONCLUSIONS: These data indicate that our multidisciplinary treatment protocol appears effective in reducing pain in the majority of patients with chronic refractory pain, while postponing or even avoiding in most patients surgical interventions such as nephrectomy in most patients.

Effectiveness of Leksell gamma knife hypophysectomy on cancer-related intractable pain - a single-center experience.

OBJECTIVES: Hypophysectomy is a method used in analgesia in patients with painful bone metastases. The pain relief after this procedure is not pathophysiologically fully understood. In only a few studies Leksell gamma knife (LGK) was used for radiosurgical hypophysectomy. In our study, we performed the LGK hypophysectomy in patients with intractable cancer-related pain due to bone metastases and evaluated the impact of this method on pain relief. METHODS: From 1994 to 2020 we enrolled 20 patients with the diagnosis of disseminated carcinoma. All patients underwent radiosurgical hypophysectomy on LGK. The maximum dose was 150-200Gy. The dose to the optic pathway was 9,8Gy on average. RESULTS: Six patients died before the first follow-up and we did not receive any posttreatment information from 4 patients. In all the rest 10 evaluated patients pain relief was achieved (0-50% of pre-procedural pain). The hypophysectomy effect lasted for the rest of their lives (the mean follow-up period was 12,6 months). In three patients we observed hormonal disbalance - hypocortisolism and diabetes insipidus with good response to substitutional therapy, one patient developed a temporary abducens nerve palsy. No other adverse events were observed. CONCLUSION: Our results suggest that the LGK hypophysectomy is an effective and safe procedure to reduce cancer-related intractable pain, especially in bone metastases of hormonally dependent tumors.

Temporal Summation Predicts De Novo Contralateral Pain After Cordotomy in Patients With Refractory Cancer Pain.

BACKGROUND: Percutaneous cervical cordotomy (PCC), which selectively interrupts ascending nociceptive pathways in the spinal cord, can mitigate severe refractory cancer pain. It has an impressive success rate, with most patients emerging pain-free. Aside from the usual complications of neurosurgical procedures, the risks of PCC include development of contralateral pain, which is less understood. OBJECTIVE: To evaluate whether sensory and pain sensitivity, as measured by quantitative sensory testing (QST), are associated with PCC clinical outcomes. METHODS: Fourteen palliative care cancer patients with severe chronic refractory pain limited mainly to one side of the body underwent comprehensive quantitative sensory testing assessment pre-PPC and post-PCC. They were also queried about maximal pain during the 24 h precordotomy (0-10 numerical pain scale). RESULTS: All 14 patients reported reduced pain postcordotomy, with 7 reporting complete resolution. Four patients reported de novo contralateral pain. Reduced sensitivity in sensory and pain thresholds to heat and mechanical stimuli was recorded on the operated side (P = .028). Sensitivity to mechanical pressure increased on the unaffected side (P = .023), whereas other sensory thresholds were unchanged. The presurgical temporal summation values predicted postoperative contralateral pain (r = 0.582, P = .037). CONCLUSION: The development of contralateral pain in patients postcordotomy for cancer pain might be due to central sensitization. Temporal summation could serve as a potential screening tool to identify those who are most likely at risk to develop contralateral pain. Analysis of PCC affords a unique opportunity to investigate how a specific lesion to the nociceptive system affects pain processes.

Medial thalamotomy using stereotactic radiosurgery for intractable pain: a systematic review.

Medial thalamotomy using stereotactic radiosurgery (SRS) is a potential treatment for intractable pain. However, the ideal treatment parameters and expected outcomes from this procedure remain unclear. The aim of this systematic review is to provide further insights on medial thalamotomy using SRS, specifically for intractable pain. A systematic review was performed to identify all clinical articles discussing medial thalamotomy using SRS for intractable pain. Only studies in which SRS was used to target the medial thalamus for pain were included. For centers with multiple publications, care was taken to avoid recounting individual patients. The literature review revealed six studies describing outcomes of medial thalamotomy using SRS for a total of 125 patients (118 included in the outcome analysis). Fifty-two patients were treated for cancer pain across three studies, whereas five studies included 73 patients who were treated for nonmalignant pain. The individual studies demonstrated initial meaningful pain reduction in 43.3-100% of patients, with an aggregate initial meaningful pain reduction in 65 patients (55%) following SRS medial thalamotomy. This effect persisted in 45 patients (38%) at the last follow-up. Adverse events were observed in six patients (5%), which were related to radiation in five patients (4%). Medial thalamotomy using SRS is effective for select patients with treatment-resistant pain and is remarkably safe when modern radiation delivery platforms are used. More posteriorly placed lesions within the medial thalamus were associated with better pain relief. More studies are warranted to shed light on differences in patient responses.

Long term results of Dorsal Root Entry Zone (DREZ) lesions for the treatment of intractable pain: A systematic review of the literature on 1242 cases.

BACKGROUND: Different Dorsal root entry zone (DREZ) lesion techniques have been reported as effective treatment for intractable painful conditions, though with contradictory results. Overall, good results were reported especially in specific conditions, such as pain due to brachial plexus avulsion, spinal cord injuries and oncological pain management. However, data on long term results in different clinical conditions are still missing. OBJECTIVE: This study aims to systematically review the pertinent literature to evaluate indications, clinical outcomes, and complications of DREZ lesion (DREZotomy), in chronic pain management. METHODS: A systematic literature review was conducted according to the PRISMA statement. Papers on DREZotomy for chronic pain in cancer, brachial plexus avulsion, spinal cord injury, post herpetic neuralgia, and phantom limb pain were considered for eligibility. For each category we further identified two sub-group according to the length of follow up: medium term and long term follow up (more than 3 years) respectively. RESULTS: 46 papers, and 1242 patients, were included in the present investigation. When considering long term results DREZotomy provided favorable clinical outcomes in brachial plexus avulsion and spinal cord injury, in 60.8% and 55.8% of the cases respectively. Conversely, the success rate was 35.3% in phantom limb pain and 28.2% in post herpetic neuralgia. A poor clinical outcome was reported in over than 25% of the patients suffering from phantom limb pain, post herpetic neuralgia and spinal cord injury. The mean complications rate was 23.58%. While BPA and SCI patients presented stable improvement over time, good outcomes among PHN and PLP groups dropped by - 46.2%; and - 14.7% at long term follow up respectively. CONCLUSION: DREZotomy seems to be an effective treatment for chronic pain conditions, especially for brachial plexus avulsion, spinal cord injury and intractable cancer/post-radiation pain. According to the low level of evidence of the pertinent literature, further studies are strongly recommended, to better define potential benefits and limitations of this technique.

Punctate Midline Myelotomy: A Historical Overview and Case Series with Detailed Efficacy and Side Effect Profiles.

OBJECTIVE: To review our experience with punctate midline myelotomy (PMM) for malignant and benign visceral pain with an emphasis on detailed side-effect profiles and efficacy. METHODS: Thirteen adults (5 men) underwent microsurgical transverse-crush PMM. RESULTS: Median follow-up for the benign pain group (n = 6) was 17.5 months (10-72) and for the malignant group (n = 7) was 8 months (0.5-31). Five of seven patients in the malignant pain group obtained excellent, lasting relief. Two had initial relief followed by worsening pain with disease progression. In the benign pain group, two patients with endodermal-origin pain (gastrointestinal tract, bladder) had complete, long-lasting relief. Three patients with mesodermal-origin pain (ureter) had excellent relief for 2-3 months, followed by recurrence in two and partial (40%) recurrence in the third. One man with pre-existing cervical myelopathy underwent PMM for benign testicular-region pain from which he had long-term relief but only transient relief of coexisting low-back and leg pain. There were no motor deficits in either group, and all patients remained ambulatory and continent. The most common side effect was transient numbness of the medial leg and foot. Two patients (both with pre-existing spinal pathology) reported persistent moderate reduction of bowel, bladder, and sexual sensation. CONCLUSIONS: PMM offers substantial pain relief for carefully selected patients with intractable visceral pain. Relief from primarily endoderm-derived structures was most complete and long-lasting. Relief from mesoderm-derived structures was typically transient or incomplete. There was essentially no relief from pain of ectoderm-derived structures. Detailed preoperative counseling is important, especially for those with pre-existing neurologic deficits.

Pituitary Radiosurgery for Management of Intractable Pain: Tokyo Women's Medical University Experience and Literature Review.

Surgical or chemical hypophysectomy has historically shown good effectiveness in management of intractable pain but has often been accompanied by serious complications. In contrast, high-dose irradiation of the pituitary gland and stalk provides comparable analgesic effects and is associated with minimal morbidity. Although its physiological mechanism remains elusive, pituitary radiosurgery using the Gamma Knife has demonstrated high clinical efficacy and safety in cases of both cancer pain and noncancer pain. According to the available data, this treatment provides at least a temporary analgesic effect in >80% of patients, usually within hours to days after the procedure. Although the pain relief is most prominent and durable in cases of metastatic bone disease, it is not limited to that pathological condition or to cases of hormone-dependent cancers. Nevertheless, the low-quality studies reported to date cannot support any meaningful clinical recommendations on use of pituitary radiosurgery. Therefore, additional well-elaborated clinical and basic investigations, preferably performed in a multi-institutional and prospective fashion, are clearly needed and may bolster further developments of this highly promising treatment modality.

Stereotactic Radiofrequency Thalamotomy for Cancer Pain: A Systematic Review.

Pain is a common occurrence in patients with cancer, which, in some cases, is not adequately controlled with medical analgesia. Thalamotomy is a treatment option in such circumstances, but synthesis of historical evidence and thalamic stratified data are lacking. We therefore sought to systematically review evidence supporting radiofrequency thalamotomy for intractable cancer pain. This review was performed using multiple electronic databases and a (PICO) patient/problem, intervention, comparison, outcome search with the terms "radiofrequency thalamotomy" and "cancer pain." Of 22 full-text studies assessed for eligibility, 14 were included for review. Articles were excluded in which radiofrequency ablation was not used, chronic implantation was used, or the study did not include patients with cancer pain. Thirteen case series and 1 case report were included. Thalamic targets included ventral posterior, central lateral, dorsomedial, centromedian, centromedian/parafascicular, centromedian and anterior pulvinar, pulvinar, limitans, suprageniculate and posterior nuclei. Patient characteristics, operative methods, lesioning parameters, patient follow-up, and outcomes were variably reported across the studies. Where relevant outcome data were available, 97% of patients experienced initial pain relief and 79% experienced significant lasting relief. Adverse events were typically transient. We conclude that radiofrequency thalamotomy for cancer pain is well tolerated and can produce significant relief from intractable cancer pain. No superiority of thalamic target could be determined.

A Clinical Review of Slipping Rib Syndrome.

ABSTRACT: Slipping rib syndrome is pain created at the lower, anterior border of the rib cage when performing upper-extremity activities, coughing, laughing, or leaning over. Defects in the costal cartilage of ribs 8 to 10 result in increased movement of the ribs, impinging soft tissue and intercostal nerves. Advancements have been made in the diagnosis of slipping rib syndrome by dynamic ultrasound. Ultrasound can identify abnormalities in the rib and cartilage anatomy, as well as soft tissue swelling. Although the mainstays of treatment continue to be reassurance, nonsteroidal anti-inflammatory drugs, physical therapy, intercostal nerve injections, osteopathic manipulative treatment, surgery for refractory pain, and botulinum toxin injections have been attempted, and there may be a role for prolotherapy in treatment. Surgical techniques are being examined secondary to recurrence of pain following resection. The hooking maneuver and surgery remain important for identification and treatment, respectively.

Cervical Cordotomy for Intractable Pain: Do Postoperative Imaging Features Correlate with Pain Outcomes and Mirror Pain?

BACKGROUND AND PURPOSE: Percutaneous cervical cordotomy offers relief of unilateral intractable oncologic pain. We aimed to find anatomic and postoperative imaging features that may correlate with clinical outcomes, including pain relief and postoperative contralateral pain. MATERIALS AND METHODS: We prospectively followed 15 patients with cancer who underwent cervical cordotomy for intractable pain during 2018 and 2019 and underwent preoperative and up to 1-month postoperative cervical MR imaging. Lesion volume and diameter were measured on T2-weighted imaging and diffusion tensor imaging (DTI). Lesion mean diffusivity and fractional anisotropy values were extracted. Pain improvement up to 1 month after surgery was assessed by the Numeric Rating Scale and Brief Pain Inventory. RESULTS: All patients reported pain relief from 8 (7-10) to 0 (0-4) immediately after surgery (P = .001), and 5 patients (33%) developed contralateral pain. The minimal percentages of the cord lesion volume required for pain relief were 10.0% on T2-weighted imaging and 6.2% on DTI. Smaller lesions on DWI correlated with pain improvement on the Brief Pain Inventory scale (r = 0.705, P = .023). Mean diffusivity and fractional anisotropy were significantly lower in the ablated tissue than contralateral nonlesioned tissue (P = .003 and P = .001, respectively), compatible with acute-phase tissue changes after injury. Minimal postoperative mean diffusivity values correlated with an improvement of Brief Pain Inventory severity scores (r = -0.821, P = .004). The average lesion mean diffusivity was lower among patients with postoperative contralateral pain (P = .037). CONCLUSIONS: Although a minimal ablation size is required during cordotomy, larger lesions do not indicate better outcomes. DWI metrics changes represent tissue damage after ablation and may correlate with pain outcomes.

Neuroablative surgical treatments for pain due to cancer.

Cancer pain is common and challenging to manage - it is estimated that approximately 30% of cancer patients have pain that is not adequately controlled by analgesia. This paper discusses safe and effective neuroablative treatment options for refractory cancer pain. Current management of cancer pain predominantly focuses on the use of medications, resulting in a relative loss of knowledge of these surgical techniques and the erosion of the skills required to perform them. Here, we review surgical methods of modulating various points of the neural axis with the aim to expand the knowledge base of those managing cancer pain. Integration of neuroablative approaches may lead to higher rates of pain relief, and the opportunity to dose reduce analgesic agents with potential deleterious side effects. With an ever-increasing population of cancer patients, it is essential that neurosurgeons maintain or train in these techniques in tandem with the oncological multi-disciplinary team.

Lumbar Sympathetic Block for Intractable Lower-Limb Postherpetic Neuralgia: Report of Two Cases.

Lumbar sympathetic block is a commonly used technique for sympathetically mediated pain syndromes. Postherpetic neuralgia (PHN) is also accepted to be associated with sympathetic system activation. While sympathetic blocks were utilized for upper-extremity or face-related PHN, there has not been any report regarding lower-extremity PHN, as it is an uncommon region. Here, we present two cases of systemic drug-resistant PHN in lower limb, relieved with lumbar sympathetic block. Both patients had at least 50% reduction in numeric rating scale (NRS) scores at the end of 6 months. Lumbar sympathetic block could be considered in the treatment of lower-limb PHN. More reports and controlled trials are needed for further understanding the role of the intervention in this neuropathic pain syndrome.