Intra-articular injection of autologous fat tissue in the treatment of patients with chronic knee pain due to osteoarthritis.

OBJECTIVES: The purpose of this study was to evaluate the safety and efficacy of autologous fat tissue injection into the knee joint for the treatment of osteoarthritis. METHODS: We reviewed 165 patients who received an intra-articular injection of autologous fat tissue for knee osteoarthritis. The efficacy of the treatment was evaluated at 1, 3, 6, and 12 months follow-up using the Visual Analogue Scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Oxford Knee Score (OKS). Patients with knee arthritis were classified as grades I-IV according to the Kellgren-Lawrence scale (K-L). The clinical and demographic information of the patients, NSAIDs or opioid use, and the side effects related to the procedure were recorded. RESULTS: There were 62 male and 103 female patients. The mean age was 61.28±11.4 years, and the mean BMI was 26.23±4.49. A significant improvement (p<0.001) was observed in VAS, WOMAC, and OKS values of patients with K-L grade I-III osteoarthritis. Patients with K-L grade IV osteoarthritis showed no statistically significant improvement. No serious complications were observed in the patients. In addition, a statistically significant decrease was found in the daily doses of paracetamol/tramadol and in the number of patients who continued to use NSAIDs after 12 months of follow-up. CONCLUSION: The results of the study suggest that minimally manipulated autologous fat tissue injections are effective and safe treatment methods for patients with grade I-III knee osteoarthritis. The results may not be satisfactory in severe osteoarthritis due to the limited capabilities.

Comparison of Greater Occipital Nerve Blockade and Sphenopalatine Ganglion Blockade in Patients with Episodic Migraine.

Objectives: Compare the effects of greater occipital nerve (GON) and sphenopalatine ganglion (SPG) blocks on headache intensity and duration, number of headache days, and disability in patients with episodic migraine. Methods: In this prospective single-blind randomized study, patients with episodic migraine were randomly divided into two groups: GON and SPG block groups. Patients received blocks once a week for 4 weeks, and once a month for 2 months. The number of headache days, the headache duration, numeric rating scale (NRS) scores, and number of acute medical treatments were assessed before the procedures and 1 month, 2 months, and 3 months after the procedures. Disability was evaluated using the migraine disability assessment (MIDAS) questionnaire at baseline and 3 months after treatment. This study protocol is registered at ClinicalTrials.gov (NCT06243874.). Results: 19 patients in the GON block group and 18 patients in the SPG block group were evaluated. Significant improvements in pain severity, headache duration, number of headache days, and the need for acute medical treatment were observed in the 1st, 2nd, and 3rd months compared to baseline in the two groups (p < 0.001). There were significant improvements in the MIDAS scores in the third month (p < 0.001). The GON block group showed a greater reduction in headache intensity, duration, number of headache days, and MIDAS scores compared to the SPG block group in the 3rd month (p < 0.001). Conclusions: GON block reduces headache duration, intensity, the number of headache days, and the need for acute medical treatment much more than SPG block in patients with episodic migraine.

Postoperative Chronic Pain Syndrome and Risk Factors in Patients with Breast Surgery.

OBJECTIVE: To investigate the incidence of chronic postoperative pain after different types of breast surgery, and investigate the risk factors associated with chronic postoperative pain. STUDY DESIGN: Descriptive study. Place and Duration of the Study: Ankara University, Faculty of Medicine, Ibnisina Hospital, from January to May 2021. METHODOLOGY: Postoperative chronic pain syndrome and risk factors were investigated in 200 female patients who underwent breast surgery for different reasons. The relationships between preoperative chronic pain, analgesic drug use, number of previous surgeries, anxiety, depression levels, lifestyle, age, height, body mass index, education level, postoperative acute pain, and postoperative sixth-month pain level were statistically analysed. RESULTS: Chronic postoperative pain was observed at a rate of 30%. Postmastectomy syndrome was observed with a rate of 31.6%. A statistically significant relationship was found between preoperative chronic pain, smoking, analgesic use, and postoperative chronic pain (p<0.001). Total mastectomy, mastectomy and simultaneous reconstructive surgery, axillary surgery were associated with chronic pain (p<0.001). A strong correlation was observed between preoperative anxiety (r=0.758, p<0.001), depression (r=0.773, p<0.001), and chronic pain. CONCLUSION: Chronic postoperative pain and postmastectomy pain syndrome are found in almost one-third of the operated patients mainly related to preoperative smoking, analgesic use, breast cancer, and psychological state. KEY WORDS: Chronic pain, Breast neoplasms, Mastectomy, Anxiety, Depression.

Efficacy of an Intra-articular Ozone Injection for Chronic Knee Pain Due to Osteoarthritis.

Context: Osteoarthritis (OA) is the most common form of arthritis, affecting an estimated 302-million people worldwide, and it's a leading cause of disability among older adults. Current treatments for OA are largely unsatisfactory. Ozone is an inexpensive, accessible, and easily applicable treatment for OA. Objective: The study aimed to retrospectively evaluate the effects of a short-term, three-month OA treatment using an intra-articular ozone injection, on pain and physical function in patients with stage 2-3 knee OA. Design: The research team designed the study as a retrospective review of files from a hospital's archive as well as the results of a follow-up questionnaire about pain that patients completed at a related clinic. Setting: The study took place at the Algology Clinic at Ankara University in Ankara, Turkey. Participants: Participants were 94 patients, aged between 28 and 75 years, with stage 2-3 OA who had applied to the clinic between January 1, 2018 and January 1, 2020 and had received an intra-articular ozone injection. Intervention: Participants received intra-articular ozone treatments at a dose of 10 ml at 15 mcg/ml for 4 weeks, once a week. Outcome Measures: Participants completed a visual analogue score (VAS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), measuring pain at baseline and at one month and at 3 months postintervention. The study also determined if the treatment had an effect on analgesic drug use and measured patient satisfaction. Results: The decreases in participants' pain scores on both scales were statistically significant at one month and at 3 months postintervention (P = .000). The need for analgesic medication had decreased for 56 participants (61.5%) at one month postintervention and for 50 (54.9%) at 3 months postintervention. Of the 94 participants, 66 (70.2%) were satisfied and 28 (29.8) weren't. Conclusions: The intra-articular injection of ozone, applied once a week for 4 weeks, resulted in a reduction in pain in stage 2-3 knee OA, without any side effects. However, further studies are needed to resolve the uncertainties in dosage, number of sessions, and intervals for intra-articular ozone injections. The current study's results need support from further prospective studies that can evaluate the efficacy of ozone treatment for a longer period of time.

The Correlation of Epidural Fibrosis with Epiduroscopic and Radiologic Imaging for Chronic Pain after Back Surgery.

BACKGROUND: Chronic low back pain is observed frequently after lumbar spinal surgery. Epidural fibrosis has been implicated in the etiology of persistent pain after back surgery. The incidence of epidural fibrosis increases as the number and extent of spinal surgery increases. Epidural fibrosis can be detected by conventional radiologic methods [e.g., lumbosacral magnetic resonance imaging (MRI) with gadolinium], but these methods are insufficient to reveal the presence of epidural adhesions. Imaging of the epidural cavity using an epiduroscope is one of the best methods for visualizing the spinal cavity without damaging anatomic structures. OBJECTIVES: To evaluate the correlation between the type and number of surgery and the degree of epidural fibrosis and to compare epidural fibrosis in epiduroscopic and MRI findings in patients with failed back surgery syndrome (FBSS). STUDY DESIGN: A prospective trial. SETTING: A university hospital. METHODS: This study included 61 patients with persistent low back pain and/or radicular pain for at least 6 months, despite lumbar surgery and conservative treatment, and who accepted epiduroscopic imaging. All patients were evaluated in a physical examination using a visual analog scale (VAS) per the elapsed time after surgery. The patients were divided into 3 groups according to the number and type of surgeries. Epidural fibrosis was rated using MRI with gadolinium and epiduroscopy. RESULTS: When the relationship between admission symptoms and epidural fibrosis was evaluated, MRI findings of fibrosis were found to be significantly higher in all patients with both lumbar and radicular pain symptoms at the confidence level of 95% (P = 0.001). The degree of fibrosis detected using epiduroscopy was grade 1 and 2 in almost all patients who presented with low back pain only, only radicular pain, or only distal paresthesia (P = 0.001). In the correlation analysis between the duration of the postoperative period (4.13 ± 2.97 years) and the degree of fibrosis detected using MRI and epiduroscopy, a statistically significant relationship was found at the confidence level of 95% (P < 0.05). As the number and extent of spinal surgeries increased, the incidence of MRI fibrosis increased, which is compatible with the literature (P = 0.001) There was a statistically significant relationship between the degree of fibrosis as detected using MRI and epiduroscopy at the confidence level of 95% (P < 0.05). Differently, we observed that 6 patients had grade 1 fibrosis as diagnosed using epiduroscopy, whereas none had fibrosis on MRI. LIMITATIONS: We did not have a control group. Further studies are required to demonstrate the relevance of these 2 imaging techniques (epiduroscopy and MRI) in terms of detecting epidural fibrosis in patients with FBSS.  CONCLUSIONS: Epiduroscopic imaging seems to be more sensitive than MRI in detecting grade I epidural fibrosis in patients with FBSS. Thus, the possibility of low-grade epidural fibrosis as a source of pain after back surgery, should be kept in mind in normally reported MRIs. Treatment should be planned accordingly.

Acute rhabdomyolysis following epidural steroid injection: An unusual complication in a patient with low back pain.

Epidural steroid injection is a very common intervention in the treatment of low back pain and sciatic symptoms. The most common complication for epidural steroid injection is transient headache with or without identifiable dural puncture. Other complications have also been reported, including intravascular entry, local hematoma, bleeding, increased back pain, facial flushing, vasovagal reactions, nausea, and fever. We report a case of rhabdomyolysis following epidural steroid injection for lumbar radiculopathy.

Clinical results of intradiscal hydrogel administration (GelStix) in lumbar degenerative disc disease

Background/aim: Degenerative disc disease (DDD) is one of the main causes of lower back pain. In this study, we evaluate the efficacy of percutaneous intradiscal GelStix administration in patients with discogenic pain due to lumbar DDD who were unresponsive to conservative methods. Materials and methods: A total of 29 patients were included in the study, which took place between 2013 and 2017. Sedation was performed in the prone position in the operating room, and a C-arm was located so as to provide a lateral view of the surgical field. A 22-G, 3.5-inch needle was inserted into the center of the disc under fluoroscopy guidance, and a percutaneous intradiscal GelStix implantation was performed. All patients were evaluated using the Oswestry Disability Index (ODI) and a visual analogue scale (VAS) before and after treatment, and using the Patient Satisfaction Scale at 12 months following treatment. Results: The mean VAS scores were 7.14 ± 0.64 at baseline and 2.48 ± 0.63 at 12 months (P < 0.001). The mean ODI scores were 28.14 ± 1.81 at baseline and 17.35 ± 0.67 at 12 months (P < 0.001). There was a statistically significant decrease in the VAS and ODI scores before and after treatment. A total of 86.2% of the patients rated the procedure as very good or good at 12 months. Conclusion: Our study results suggest that GelStix treatment is useful in pain relief in patients with DDD from the first month of treatment.

Percutaneous navigable intradiscal decompression in treatment of lumbar disc herniation: a single-center experience

Background/aim: Minimally invasive procedures have been increasingly used for the treatment of herniated discs. Nonsurgical interventions minimize the secondary damage to other tissues and shorten the length of hospital stay by avoiding general anesthesia. Possible complications are thermal injuries, root injury, discitis, endplate damage, dural injury, meningitis, infection, increase in pain, and muscle spasm. We aimed to evaluate the efficacy of percutaneous decompression therapy by using intradiscal navigable electrodes on pain and functional movement index in patients with herniated nucleus pulposus (HNP). Materials and methods: A total of 209 patients with protrusive lumbar disc herniation underwent percutaneous ablation decompression treatment using an intradiscal routable electrode (L-Disq) in our pain clinic. Visual analog scale (VAS) and Oswestry Disability Index (ODI) scores were recorded at the beginning and at the 1st, 3rd, 6th, and 12th months after treatment. Patient satisfaction was evaluated at the 12th month by a patient satisfaction scale (PSS). Results: When compared to initial values, VAS and ODI scores showed statistically significant improvement at the 1st, 3rd, 6th, and 12th months (P < 0.001). Mean VAS scores were 7.28 and 3.03 points (P < 0.001) while mean ODI scores were 32.46 and 20.48 points (P < 0.001) at the beginning and at the 12th month, respectively. Satisfaction rate of all patients was 81%. We also attempted to treat the existing annular fissure using an ablation method and we believe that treating the herniated disc together with the fissure in the same session increased our success rate. Conclusion: With clinical evidence, we suggest that L-Disq may be considered as an appropriate option with a low risk of complications in pain management in cases of lumbar disc herniation that are resistant to conservative methods.

Percutaneous plasma laser disc coagulation and navigable ablation decompression in the treatment of cervical disc herniation: a single center experience

Background/aim: We aimed to compare the effectivity of percutaneous disc coagulation therapy (PDCT) and navigable ablation decompression treatment (L-DISQ) in patients who were diagnosed with cervical disc herniation. Materials and methods: Visual analog scale (VAS) and Neck Pain Index (NPI) scores were recorded initially and at the 1st, 3rd, 6th, and 12th months after the procedures. Patient Satisfaction Scale (PSS) scores were recorded 12 months after the procedures Results: Mean VAS scores were 7.55 and 3.1 points in the PDCT group and 7.6 and 3.00 points in the L-DISQ group; mean NPI scores were 34.2 and 20.75 points in the PDCT group and and 34.1 and 20.4 points in the L-DISQ group initially and at the 12th month. When compared between months, there was a significant decrease in time-dependent VAS and NPI scores in both PDCT and L-DISQ groups (P = 0.001). Some complications included esophageal, vascular, and neural injuries; hoarseness; Horner syndrome; infections; dural puncture; and muscle spasm. The only difference between groups was the rate of cervical spasm within 1 month after the procedure: 75% in the PDCT group and 15% in the L-DISQ group. Conclusion: The diameter of the canal of the cervical vertebrae is narrower than of the lumbar and thoracic regions; therefore, the smaller part of the disc may be sufficient to create clinical signs. The response to decompression therapies is faster in the case of cervical percutaneous procedures that are performed correctly. Proper patient selection and practitioner's experience are important in the treatment success

Evaluation of the efficacy of epiduroscopic adhesiolysis in failed back surgery syndrome

Background/aim: We aimed to compare the results of the treatment of the patients with failed back surgery syndrome (FBSS) by mechanical lysis and steroid hylase injection via epiduroscopy due to their stabilization status and to detect the effect of pathological diagnostic markers on prognosis and ongoing treatment protocol. Materials and methods: Eighty-two patients with FBSS symptoms were included. Two groups were composed as group I (stabilized) and group II (nonstabilized). All patients were evaluated using the oswestry disability index (ODI) and visual analogue scale (VAS) scores before and after treatment at 1, 3, 6, and 12 months and using the patient satisfaction scale at 12 months following treatment. Epidural scar tissue visual and mechanical signs were also recorded. Results: Mean VAS scores were 7.8 and 3.28 points in group I (P < 0.001) and 7.51 and 2.74 points in group II (P < 0.001) at the beginning and at 12 months, respectively. Mean ODI scores were 34.05 and 22.16 points in group I (P < 0.001) and 30.74 and 19.46 points in group II (P < 0.001) at the beginning and at 12 months. VAS and ODI scores decreased significantly in both groups, but were more significant in the nonstabilized group (P < 0.001). Moderate or severe fibrous tissue was observed in 86.58% of the patients and patient satisfaction scores were very good or good in 78.06% of the patients. During the procedure, a dura rupture developed in four patients in the stabilization group and in two patients in the nonstabilization group; however, none of these patients developed a spinal headache and no significant permanent complication arose. Conclusion: We suggest that epidural adhesiolysis, hyaluronidase, and steroid injection in patients with FBSS chronic low back pain and/or radicular symptoms may give reliable information about the quality of life, accuracy of diagnosis, and the possible course of the present findings and may be more effective in nonstabilized patients

Effectiveness of Percutaneous Intradiscal Decompression Therapy in Thoracic Disc Herniation

Aims: Although there have been many studies about lumbar and cervical ablation procedures, few studies have been performed in the thoracic region. To evaluate the clinical results of a percutaneous disc decompression device in patients with radicular symptoms and/or dorsal pain due to thoracic disc herniation. Methods: Eleven patients with thoracic disc herniation and/or degenerative discs (all in T10-T11, or T11-T12 levels) who did not respond to conservative treatments were undergoing ablation and compression procedures. Pain and radicular symptoms consistent with the thoracolumbar region were confirmed via abnormal magnetic resonance imaging findings after detailed anamnesis and physical examination. All patients were evaluated before and 1, 3, 6, and 12 months after treatment using the visual analog scale score. The patient satisfaction scale was used to evaluate the level of patient satisfaction at the end of the treatment at 12 months. Results: The median visual analog scale score was 7.00±0.45 points before treatment and 2.73±0.65 points at 12 months post-procedure and were statistically significant (p<0.001). The results of pairwise comparisons using the Bonferroni Corrected Wilcoxon Signed-Rank test showed that there were statistically significant differences. The mean visual analog scale score at the beginning (7.00±0.45) was significantly higher than the mean score of other months. Postoperative improvement was significant with a 99% confidence interval. No complications that may cause permanent damage occurred. Conclusion: Percutaneous disc decompression is an effective and safe procedure to treat pain caused by lower thoracic intervertebral disc disease, which did not respond to conservative treatments.

[Thoracic outlet syndrome: A case of scalene muscle hypertrophy in long-term follow-up of diagnosis of cervical discopathy]. / Uzun süre servikal diskopati tanisi ile izlenen skalen kas hipertrofisinin neden oldugu torasik outlet sendromu.

Described in this article is diagnosis and treatment of mixed type of thoracic outlet syndrome (TOS) resulting from scalene muscle hypertrophy. Many diseases should be considered in the differential diagnosis to definitively diagnose this syndrome, and it is necessary to ask about activities of daily life, in addition to adding provocative tests to physical examination and examining electrophysiological and imaging results. Once diagnosed, even if complaints decrease with conservative treatment, surgery may be required. However, in patients diagnosed late, despite decrease in complaints after surgery, neurological deficit may remain.

The comparison of the efficacy of radiofrequency nucleoplasty and targeted disc decompression in lumbar radiculopathy.

Chronic low back pain is a common clinical condition causing medical, socioeconomic, and treatment difficulties. In our study, we aimed to compare early and long-term efficacy of lumbar radiofrequency thermocoagulation (RFTC) nucleoplasty and targeted disc decompression (TDD) in patients with lumbar radiculopathy in whom previous conventional therapy had failed. The medical records of 37 patients undergoing TDD and 36 patients undergoing lumbar RFTC nucleoplasty were retrospectively examined and assigned to the Group D and Group N, respectively. In all patients Visual Analogue Scale (VAS) and Functional Rating Index (FRI) were recorded before treatment and after one, six and twelve months after the procedure. The North American Spine Society Satisfaction Scale (NASSSS) was also recoreded twelve months after the therapeutic procedure. Statistically significant postprocedural improvement in VAS and FRI was evident in both groups. VAS scores after one, six, and twelve month were slightly higher in Group N, compared to Group D. The overall procedure-related patient satisfaction ratio was 67.5% in the Group D, compared to 75% in the Group N. Regardless of the different mechanism of action, both methods are effective therapies for lumbar radiculopathy, with TDD showing long-term lower pain scores.

Comparison of ropivacaine 0.2% and 0.25% with lidocaine 0.5% for intravenous regional anesthesia.

STUDY OBJECTIVE: To compare the anesthetic effects of two different concentrations and doses of ropivacaine (0.2% and 0.25%) with those of a conventional dose of lidocaine 0.5%. DESIGN: Prospective, randomized, double-blinded, clinical investigation. SETTING: Large metropolitan university hospital. PATIENTS: 66 adult ASA physical status I and II patients undergoing forearm and hand surgery. INTERVENTIONS: Patients were randomly allocated to three groups to receive intravenous regional anesthesia (IVRA). Study groups were: ropivacaine 0.2% (Group I, n = 22), ropivacaine 0.25% (Group II, n = 22), and lidocaine 0.5% (Group III, n = 22). MEASUREMENTS: Tourniquet tolerance times and regression of sensory analgesia were noted. Verbal numerical pain scores (VNS), cumulative analgesic consumption, and side effects were recorded during surgery and postanesthesia care unit (PACU). Time to first pain medication intake and number of patients receiving analgesics in the PACU were recorded. MAIN RESULTS: Additional tolerance times for the distal tourniquet were significantly higher in the ropivacaine 0.25% group than the other two groups. Regression of sensory anesthesia was fastest in the lidocaine group. During the PACU stay, VNSs were significantly lower in the first 20 minutes in the ropivacaine groups than the lidocaine group. Time to first intake of pain medication in the PACU was soonest in the lidocaine group. The number of patients given analgesics in the PACU was highest in the lidocaine group. The number of patients taking > two tablets of tramadol was significantly lowest in the ropivacaine 0.25% group. No serious side effects were observed in any study group. CONCLUSION: Longer tolerance times for the distal tourniquet, prolonged analgesia after tourniquet release, and lower analgesic requirements postoperatively make ropivacaine 0.2% and 0.25% an alternative to lidocaine for IVRA.

Evaluation of the longus colli muscle in relation to stellate ganglion block.

BACKGROUND AND OBJECTIVES: The longus colli (LC) muscle is an important structure of the anterior cervical spine and has a critical role in stellate ganglion block. This technique involves withdrawing the needle to locate its port for injection above the anterior surface of the LC muscle; however, its exact thickness at the C5, C6, and C7 levels has not been measured. The aim of this anatomic and magnetic resonance-supported study was to evaluate the thickness of the LC muscle at these levels from the anterior tubercle of each vertebra toward the vertebral body at 5-, 10-, and 15-mm distances to provide precise anatomic data for stellate ganglion block. METHODS: Ten cadavers, 60 vertebral body specimens, and cervical magnetic resonance imaging (MRI) scans of 40 adult patients were used for measurements. RESULTS: The main findings of this study are that the thickness of the LC muscle varies between 5.0 and 10.0 mm at C6 and C7 in cadavers and between 8.0 and 10.0 mm in MRI scans. Sex has an important role; MRI scans revealed that male patients have a considerably thicker LC muscle at each vertebral level. CONCLUSION: We found a highly variable thickness of the LC muscle in anatomic and imaging studies, which may lead to negative block results.

Sympathetic radiofrequency neurolysis for unilateral lumbar hyperhidrosis: a case report.

Patients with hyperhidrosis suffer from physical, social and mental discomfort which often cannot be treated sufficiently using conservative measures. A new percutaneous approach to sympathectomy using radiofrequency denervation has seemed to offer longer duration of action and less incidence of post sympathetic neuralgia. This article reports the authors' experience with sympathetic RF neurolysis in a 35 year old male with right unilateral lumbar hyperhidrosis. Under scopy guided localization of the lumbar spine sympathetic blockade with local anesthetics to L2-5 vertebral levels were performed as a diagnostic block. Lesion effectiveness is monitored by bilateral feet skin temperature measurement. Clinical effects produced by the first sympathetic ganglion block were sustained for 1 week and then RF neurolysis of lumbar sympathetic ganglion was performed to the same levels for a longer effect. The procedure was accomplished within 30 minutes and the patient was discharged within 2 hours after the procedure. Hyperhidrosis was relieved after the procedure and there were no postsympathectomy neuralgia and sexual dysfunction. The patient obtained improvement of lumbar hyperhidrosis at his first month of follow- up and was satisfied with the outcome. In conclusion, RF neurolysis of lumbar sympathetic ganglions is a safe and effective palliative procedure with minimal invasiveness for relieving excessive sweat secretion in patients with localized hyperhidrosis.

Effects of interleukin-1 beta, interleukin-6, and tumor necrosis factor on sensitivity of dorsal root ganglion and peripheral receptive fields in rats.

This study was designed to characterize the effects of low doses (0.5-5 ng) of pro-inflammatory cytokines, interleukin-1 beta (IL-1beta), interleukin-6 (IL-6), and tumor necrosis factor (TNF), on the neural activity of dorsal root ganglion (DRG) in rats. The purpose of this study was to examine the effects of cytokines (IL-1beta, IL-6, and TNF) on the somatosensory neural response of DRG. The release of inflammatory cytokines by an injured disc may play a critical role in pain production at nerve endings, axons, and nerve cell bodies. Herniated disc tissue has been shown to release IL-1beta, IL-6, TNF, and other algesic chemicals. Their effects on nerve endings in disc and adjacent tissue may lead to low back pain and their effects on dorsal root axons and ganglia may lead to sciatica. Exposed lumbar DRGs were investigated by electrophysiologic techniques. Sham (mineral oil), control (carrier solution), or IL-1beta, IL-6, or TNF at doses of 0.5, 1, and 5 ng were applied over the DRG. Baseline discharge rates as well as mechanosensitivity of the DRG and peripheral receptive fields were evaluated over 30 min. Applications of IL-1beta at 1 ng resulted in an increase in the discharge rate, 5 ng resulted in an increased mechanosensitivity of the DRG in group II units. Similarly, after 1 ng TNF applications, group II units also showed an increase in mechanosensitivity of DRG and peripheral receptive fields. At low doses IL-1beta and TNF sensitization of receptive fields were observed. The responses observed in the group II units indicate that a sub-population of afferent units might have long-term effects modifying the sensory input to the central nervous system. This study provides added evidence to the role of cytokines in modulating afferent activity following inflammation.

Dorsal root sensitivity to interleukin-1 beta, interleukin-6 and tumor necrosis factor in rats.

The release of inflammatory cytokines caused by a disrupted disc may play a critical role in pain production at nerve endings, axons, and nerve cell bodies. Herniated disc tissue has been shown to release inflammatory cytokines such as interleukin-1 beta (IL-1beta), interleukin-6 (IL-6), tumor necrosis factor (TNF), and other algesic chemicals. This study was designed to characterize the effects of these proinflammatory cytokines on the somatosensory neural response at the dorsal root level in rats. It is hypothesized that their effects on nerve endings in disc and adjacent tissue contribute to low-back pain, and the effects on dorsal root axons and ganglia contribute to radiculopathy and sciatica. Surgically isolated sacral dorsal roots were investigated by electrophysiologic techniques. IL-1beta, IL-6, or TNF (100 ng, each) were applied onto the dorsal roots. Neural responses and mechanosensitivity of the receptive fields were evaluated over time. The results showed that 3 h after each cytokine application, the neural activity was statistically decreased. The mechanical sensitivity of the receptive fields increased at 90 min following IL-1beta or TNF application, and returned to normal more than 3 h after IL-1beta application. IL-1beta, IL-6, and TNF may be neurotoxic to dorsal root axons. Furthermore IL-1beta and TNF may sensitize the peripheral receptive fields. This study suggests that dorsal roots may be impaired by these proinflammatory cytokines.