Efficacy and safety of pulsed radiofrequency modulation of thoracic dorsal root ganglion or intercostal nerve on postherpetic neuralgia in aged patients: a retrospective study.

BACKGROUND: Postherpetic neuralgia (PHN) is common in elderly patients and can be alleviated by pulsed radiofrequency (PRF). However, PRF treatments display different efficacy on different nerves. The purpose of this study was to evaluate the efficacy and safety of ultrasound-guided PRF modulation on thoracic dorsal root ganglion (DRG) or intercostal nerve (ICN) for PHN in aged patients and to provide a theoretical basis for clinical treatment. METHODS: We classified aged patients into two groups, DRG group and ICN group, based on the needle tip position. Visual analogue scale (VAS) and concise health status questionnaire (Short-form 36 health/survey questionnaire, SF-36) were used to evaluate the pain intensity and the life quality of the patients before and 2, 4 and 12 weeks after the PRF treatments. We also recorded the adverse reactions during the treatments. RESULTS: After the PRF treatment, the scores of VAS and SF-36 (assessing general health perception, social function, emotional role, mental health, and pain) improved significantly in both groups (P < 0.05). The mean VAS score in the DRG group was significantly lower than that in the ICN group 2 weeks after treatment, and remained for 12 weeks. The SF-36 scores in the DRG group were significantly higher than those in the ICN group (P < 0.05). We found a similar incidence of adverse reactions between the two groups (P > 0.05). CONCLUSIONS: PRF therapy is safe and effective for elderly patients with postherpetic neuralgia. However, PRF treatment in dorsal root ganglion is superior to that in intercostal nerve with improving VAS and SF-36 scores to a greater extent in older patients. TRIAL REGISTRATION: ChiCTR2100044176 .

Serotonergic innervation of respiratory motor nuclei after cervical spinal injury: Impact of intermittent hypoxia.

Although cervical spinal cord injury (cSCI) disrupts bulbo-spinal serotonergic projections, partial recovery of spinal serotonergic innervation below the injury site is observed after incomplete cSCI. Since serotonin contributes to functional recovery post-injury, treatments to restore or accelerate serotonergic reinnervation are of considerable interest. Intermittent hypoxia (IH) was reported to increase serotonin innervation near respiratory motor neurons in spinal intact rats, and to improve function after cSCI. Here, we tested the hypotheses that spontaneous serotonergic reinnervation of key respiratory (phrenic and intercostal) motor nuclei: 1) is partially restored 12 weeks post C2 hemisection (C2Hx); 2) is enhanced by IH; and 3) results from sprouting of spared crossed-spinal serotonergic projections below the site of injury. Serotonin was assessed via immunofluorescence in male Sprague Dawley rats with and without C2Hx (12 wks post-injury); individual groups were exposed to 28 days of: 1) normoxia; 2) daily acute IH (dAIH28: 10, 5 min 10.5% O2 episodes per day; 5 min normoxic intervals); 3) mild chronic IH (IH28-5/5: 5 min 10.5% O2 episodes; 5 min intervals; 8 h/day); or 4) moderate chronic IH (IH28-2/2: 2 min 10.5% O2 episodes; 2 min intervals; 8 h/day), simulating IH experienced during moderate sleep apnea. After C2Hx, the number of ipsilateral serotonergic structures was decreased in both motor nuclei, regardless of IH protocol. However, serotonergic structures were larger after C2Hx in both motor nuclei, and total serotonin immunolabeling area was increased in the phrenic motor nucleus but reduced in the intercostal motor nucleus. Both chronic IH protocols increased serotonin structure size and total area in the phrenic motor nuclei of uninjured rats, but had no detectable effects after C2Hx. Although the functional implications of fewer but larger serotonergic structures are unclear, we confirm that serotonergic reinnervation is substantial following injury, but IH does not affect the extent of reinnervation.

Intraoperative Intercostal Nerve Block for Postoperative Pain Control in Pre-Pectoral versus Subpectoral Direct-to-Implant Breast Reconstruction: A Retrospective Study.

Background and Objectives: Patients undergoing mastectomy and implant-based breast reconstruction have significant acute postsurgical pain. The purpose of this study was to examine the efficacy of intercostal nerve blocks (ICNBs) for reducing pain after direct-to-implant (DTI) breast reconstruction. Materials and Methods: Between January 2019 and March 2020, patients who underwent immediate DTI breast reconstruction were included in this study. The patients were divided into the ICNB or control group. In the ICNB group, 4 cc of 0.2% ropivacaine was injected intraoperatively to the second, third, fourth, and fifth intercostal spaces just before implant insertion. The daily average and maximum visual analogue scale (VAS) scores were recorded by the patient from operative day to postoperative day (POD) seven. Pain scores were compared between the ICNB and control groups and analyzed according to the insertion plane of implants. Results: A total of 67 patients with a mean age of 47.9 years were included; 31 patients received ICNBs and 36 patients did not receive ICNBs. There were no complications related to ICNBs reported. The ICNB group showed a significantly lower median with an average VAS score on the operative day (4 versus 6, p = 0.047), lower maximum VAS scores on the operative day (5 versus 7.5, p = 0.030), and POD 1 (4 versus 6, p = 0.030) as compared with the control group. Among patients who underwent subpectoral reconstruction, the ICNB group showed a significantly lower median with an average VAS score on the operative day (4 versus 7, p = 0.005), lower maximum VAS scores on the operative day (4.5 versus 8, p = 0.004), and POD 1 (4 versus 6, p = 0.009), whereas no significant differences were observed among those who underwent pre-pectoral reconstruction. Conclusions: Intraoperative ICNBs can effectively reduce immediate postoperative pain in subpectoral DTI breast reconstruction; however, it may not be effective in pre-pectoral DTI reconstruction.

Pseudoaneurysm of the Thoracoabdominal Aortic Graft Due to Intercostal Nerve Block.

Pseudoaneurysms of the descending aorta after open graft replacement usually occur in patients with connective tissue disorders and form at anastomotic or cannulation sites. We present a case of an iatrogenic pseudoaneurysm in the descending thoracic aortic graft body caused by intercostal nerve block. The patient had undergone repair for thoracoabdominal aortic aneurysm 4 years prior and underwent a series of intercostal nerve blocks after experiencing persistent postthoracotomy pain. A pseudoaneurysm in the descending thoracic graft, contiguous with the chest wall, was encountered. He underwent successful pseudoaneurysm resection with redo graft replacement, resulting in significant pain relief.

Paralysis of the Rectus Abdominis Muscle after a Video-Assisted Thoracoscopic Surgery.

The rectus abdominis muscle is innervated by intercostal nerves T7-T12, and most thoracotomies are performed through the fourth to sixth intercostal spaces, so direct nerve damage to the rectus abdominis seems unlikely. However, at least one trocar is inserted below the seventh intercostal space in most multi-port video-assisted thoracoscopic surgeries (VATSs), and injury of the seventh or lower intercostal nerve with related paralysis of the rectus abdominis is possible, albeit rare. Only two cases of rectus abdominis paralysis caused by after VATSs have been reported, and these cases were not permanent injuries. This is the first report of permanent paralysis of the rectus abdominis after VATSs.

Local Application of Ultrasound Attenuates Neuropathic Allodynia and Proinflammatory Cytokines in Rats After Thoracotomy.

BACKGROUND AND OBJECTIVES: We aimed to investigate the effect of therapeutic ultrasound (TU) on pain sensitivity and the concentration inflammatory cytokines in a thoracotomy rat model. METHODS: Rats were distributed randomly into 4 groups: (1) sham operated, (2) thoracotomy and rib retraction (TRR), (3) TRR rats that received TU (TRR + TU-1), and (4) TRR rats that received TU with the ultrasound turned off (TRR + TU-0). Ultrasound was set at 1-MHz frequency (1.0-W/cm intensity and 100% duty cycle for 5 minutes), began on postoperative day (POD) 10, and then continued once per day, 5 days a week for 3 weeks. RESULTS: The TRR and TRR + TU-0 rats encountered tactile hypersensitivity from PODs 10 to 28. Mechanical withdrawal thresholds were increased (all P < 0.05) following 5 days of TU, but thresholds remained significantly lower than baseline values. Therapeutic ultrasound increased the subcutaneous, but not body temperature. All groups receiving TRR demonstrated an increase in concentration of interleukin 1ß and tumor necrosis factor α (TNF-α) on POD 14; however, the rise in TNF-α concentration was less in the TU-treated group than in the others. The decrease in concentration was greatest in the TRR + TU-1 group and similar between the TRR and TRR + TU-0 groups. CONCLUSIONS: Mechanical allodynia was partially resolved with TU. Tissue temperature increased with ultrasound, while TU restricted the up-regulation of interleukin 1ß and TNF-α around the injured intercostal nerve.

Pulsed radiofrequency or anterior neurectomy for anterior cutaneous nerve entrapment syndrome (ACNES) (the PULSE trial): study protocol of a randomized controlled trial.

BACKGROUND: Some patients with chronic abdominal pain suffer from an anterior cutaneous nerve entrapment syndrome (ACNES). This somewhat illusive syndrome is thought to be caused by the entrapment of end branches of the intercostal nerves residing in the abdominal wall. If ACNES is suspected, a local injection of an anesthetic agent may offer relief. If pain is recurrent following multiple-injection therapy, an anterior neurectomy entailing removal of the entrapped nerve endings may be considered. After 1 year, a 70% success rate has been reported. Research on minimally invasive alternative treatments is scarce. Pulsed radiofrequency (PRF) treatment is a relatively new treatment for chronic pain syndromes. An electromagnetic field is applied around the nerve in the hope of leading to pain relief. This randomized controlled trial compares the effect of PRF treatment and neurectomy in patients with ACNES. METHODS: Adult ACNES patients having short-lived success following injections are randomized to PRF or neurectomy. At the 8-week follow-up visit, unsuccessful PRF patients are allowed to cross over to a neurectomy. Primary outcome is pain relief after either therapy. Secondary outcomes include patient satisfaction, quality of life, use of analgesics and unanticipated adverse events. The study is terminated 6 months after receiving the final procedure. DISCUSSION: Since academic literature on minimally invasive techniques is lacking, well-designed trials are needed to optimize results of treatment for ACNES. This is the first large, randomized controlled, proof-of-concept trial comparing two therapy techniques in ACNES patients. The first patient was included in October 2015. The expected trial deadline is December 2017. If effective, PRF may be incorporated into the ACNES treatment algorithm, thus minimizing the number of patients requiring surgery. TRIAL REGISTRATION: Nederlands Trial Register (Dutch Trial Register), NTR5131 ( http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=5131 ). Registered on 15 April 2015.

Intercostal Neuralgia Occurring as a Complication of Splanchnic Nerve Radiofrequency Ablation in a Patient with Chronic Pancreatitis.

Our intent is to report a case of intercostal neuralgia occuring as a complication of splanchnic radiofreqency ablation (RFA), due to a breach in the integrity of the insulating sheath of the RFA needle.A 48-year-old man presented to our pain clinic with upper abdominal pain due to chronic pancreatitis, recalcitrant to medical management. We decided to perform bilateral splanchnic nerve RFA in this patient. After confirmation of bilateral correct needle placement under fluoroscopic guidance and sensorimotor testing, RFA was performed on the right side uneventfully. However, during RFA on the left side, the patient experienced severe pain in the epigastric region. A bolus of fentanyl 50 µg was given intravenously in order to minimise discomfort, and RFA was performed. In the post-procedure period, the patient described severe pain in the left subcostal and epigastric region, with features suggestive of intercostal neuralgia of the left 11th intercostal nerve. We went back and analysed all the fluoroscopic images again. Convinced of correct needle placement, we examined the RFA needles which had been used for ablation in this patient. One of the needles was discovered to have a fine breach in its insulating sheath, at a distance of approximately 30 mm from the active tip. It is of utmost importance for all interventional pain physicians to perform a thorough pre-use check of the equipment prior to any RFA procedure, with special emphasis on ensuring the integrity of the insulating sheath of the needles which are to be used, in order to prevent injury of non target nerves. KEY WORDS: Splanchnic nerve block, radiofrequency ablation, intercostal neuralgia, radiofrequency ablation complications, radiofrequency equipment check, radiofrequency needle.

Modulation of serum BDNF levels in postherpetic neuralgia following pulsed radiofrequency of intercostal nerve and pregabalin.

AIM: To study the modulation of serum BDNF levels following integrated multimodal intervention in postherpetic neuralgia (PHN). MATERIALS & METHODS: A randomized, double-blind controlled study was undertaken among patients of thoracic PHN where 30 patients received pregabalin with pulsed radiofrequency and 30 controls received pregabalin with sham treatment. RESULTS: Pain intensity (visual analog scale) was reduced earlier in intervention group (15.3 ± 5.7 at the fourth week) compared with control group (16.3 ± 6.6 at the eighth week). Serum BDNF level increased with time in both the groups with overall increase more pronounced in intervention group. CONCLUSION: Integrated multimodal therapy using minimally invasive pulsed radiofrequency and pregabalin in PHN was effective in early pain reduction with elevated serum BDNF levels.

Intercostal neuralgia as a symptom of an osteoblastoma in thoracic spine.

An osteoblastoma is a benign bone lesion most commonly affecting the spine; it is frequently found in the posterior elements of the vertebra. When an osteoblastoma originates in the spine, it usually causes dull and localised dorsal pain, but the period between symptom development and diagnosis can be long. MRI shows intense peritumoural oedema accompanying the osteoblastoma. We present a case of a 15-year-old boy with osteoblastoma at the level of the T8-9 left laminae causing intercostal neuralgia without direct invasion to the intercostal nerve. Immediately after surgery, intercostal neuralgia was diminished. To our knowledge, this is the first case of an osteoblastoma with intercostal neuralgia, which is possibly the key symptom for diagnosing an osteoblastoma in the thoracic spine.

Cadaveric nerve allotransplantation in the treatment of persistent thoracic neuralgia.

When relief from neuralgia cannot be achieved with traditional methods, neurectomy may be considered to abate the stimulus, and primary opposition of the terminal nerve ending is recommended to prevent neuroma. Nerve repair with autograft is limited by autologous nerves available for large nerve defects. Cadaveric allografts provide an unlimited graft source without donor-site morbidities, but are rapidly rejected unless appropriate immunosuppression is achieved. An optimal treatment method for nerve allograft transplantation would minimize rejection while simultaneously permitting nerve regeneration. This report details a novel experience of nerve allograft transplantation using cadaveric nerve grafts to desensitize persistent postoperative thoracic neuralgia.

Chest tube insertion is one important factor leading to intercostal nerve impairment in thoracic surgery.

OBJECTIVES: Chest tube insertion seems to be one important factor leading to intercostal nerve impairment. The purpose of this prospective study was to objectively evaluate intercostal nerve damage using current perception threshold testing in association with chest tube insertion. METHODS: Sixteen patients were enrolled in this study. Intercostal nerve function was assessed with a series of 2000-Hz (Aß fiber), 250-Hz (Aδ fiber), and 5-Hz (C fiber) stimuli using current perception threshold testing (Neurometer CPT/C(®)). Current perception threshold values at chest tube insertion were measured before surgery, during chest tube insertion and after removal of the chest tube. Intensities of ongoing pain were also assessed using a numeric rating scale (0-10). RESULTS: Current perception thresholds at each frequency after surgery were significantly higher than before surgery. Numeric rating scale scores for pain were significantly reduced from 3.3 to 1.9 after removal of the chest tube (p = 0.004). The correlation between current perception threshold value at 2000 Hz and intensity of ongoing pain was marginally significant (p = 0.058). CONCLUSIONS: This is the first study to objectively evaluate intercostal nerve damage at chest tube insertion. The results confirmed that chest tube insertion has clearly deleterious effects on intercostal nerve function.

Treatment of osteoporotic vertebral compression fractures with percutaneous kyphoplasty: a report of 196 cases.

The incidence of osteoporotic vertebral compression fracture (OVCF) is increased recently. Percutaneous kyphoplasty (PKP) has recently been shown to have a curative effect on OVCF. Unfortunately, related complications arising from PKP cannot be ignored, such as cement leaks, fever, and intercostal neuralgia. This study aimed to investigate the common complications of PKP in the treatment of OVCF patients and analyze the causes and assess prevention and control measures. A total of 196 patients (204 vertebrae) underwent PKP procedures at the Department of Spine Surgery, Shenzhen Sixth People's Hospital, Guangdong, China, from June 2004 to August 2010. The data on incidence rates of the various complications were compiled. All patients were successfully operated without death, paraplegia, or pulmonary embolism. Incidence of various complications resulting from different types of bone cement leakage was 27.45 %, including 0.51 % for postoperative elevated fever, 4.08 % for intercostal neuralgia, 2.55 % for trailing of bone cement, 0.51 % for refracture at adjacent vertebrae, and 0.51 % for cerebrospinal fluid leakage. These results suggest that PKP is an effective surgical technique for the treatment of OVCF, resulting in limited trauma with satisfactory curative effects. Skillful mastery of this technology will help reduce the incidence rate of complications.

[Pasha-Cath in the treatment of post-thoracotomy pain syndrome]. / Posttorakotomi agri sendromu tedavisinde Pasha-Cath uygulamasi.

Post-thoracotomy pain syndrome is a chronic pain syndrome and is seen in approximately 5-65% of patients after thoracotomy. Post-thoracotomy pain syndrome is generally considered to be neuropathic pain due to intercostal nerve injury. A 21- year-old male patient experienced pain radiating along the incision after the thoracotomy operation. Allodynia and hyperalgesia were determined in the upper part of the incision; visual analogue scale (VAS) score was 10. Gabapentin and amitriptyline were started as medical treatment. Three months later, the patient complained of concentration difficulty at work and in daily life. Medical therapy was planned again. In view of the persisting complaints, epidural pulse radio frequency with Pasha-Cath was scheduled. After 3 weeks and also at 3 months, the VAS was 2. After 6 months, VAS remained at 2. As a result, we concluded that epidural pulse radio frequency with Pasha-Cath is an alternative and effective choice of treatment in post-thoracotomy pain syndrome when the medical treatment alone is not sufficient.

Implantation of an intercostal nerve stimulator for chronic abdominal pain.

Chronic abdominal pain is not uncommon and can be difficult to manage. We present the case of a 17-year-old man with a 4-year history of chronic abdominal pain. The patient had previously undergone abdominal surgery by way of laparoscopic appendicectomy and right nephrectomy for a mal-rotated kidney. The patient continued to suffer right-sided abdominal pain which was not controlled by analgesia. We report the successful implantation of a right D11 intercostal nerve stimulator to control the patient's pain. This is the first report of an implantable intercostal nerve stimulator to control intractable chronic abdominal pain.