Intra-articular Local Anaesthetic Research Articles

Adding Dexmedetomidine to Intra-articular Local Anesthetics Results in Prolonged Analgesia after Knee Arthroscopy: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aims to assess the efficacy and safety of dexmedetomidine as an adjuvant to intra-articular (IA) injections of local anesthetics (LA) in adult patients undergoing knee arthroscopy. We searched MEDLINE, Embase, and Cochrane Library for randomized controlled trials (RCTs) comparing IA dexmedetomidine plus LA versus LA alone for knee arthroscopy in adults. We used the DerSimonian and Laird random-effects model for all outcomes, and conducted a sensitivity analysis with the leave-one-out method, as well as a subgroup analysis for the type of LA. We used R version 4.1.2 for all statistical analyses. We included 16 RCT encompassing 799 patients, of whom 49.8% received IA dexmedetomidine. In the pooled analysis, time to first analgesia rescue was prolonged in almost 4 hours with the use of dexmedetomidine (MD 229 min; p<0.001). We found statistically significant differences favoring dexmedetomidine in pain scores at rest and movement throughout the first 2, 6, 12 and 24 hours postoperatively (p<0.001). Although the mean difference (MD) ranged from -0.3 to -0.9 cm, corresponding to a 3 to 9% reduction in pain scores, this change is not clinically significant when compared to the minimal clinically important difference (MCID). Additionally, the intervention group showed a statistically significant reduction in cumulative opioid consumption over 24 hours (MD -4.5 mg; p<0.001). However, this reduction did not meet the threshold for the MCID. There was no difference between groups on the incidence of hypotension (p=0.190), bradycardia (p=0.430) and postoperative nausea and vomiting (p=0.550). Adding dexmedetomidine to LA in IA injections for knee arthroscopy significantly extended analgesia duration. Additionally, it lowered pain scores and opioid use, although these effects did not reach the MCID. Furthermore, this addition did not increase the risk of adverse events.

Adding Dexmedetomidine to Intra-articular Local Anesthetics Results in Prolonged Analgesia after Knee Arthroscopy: A Systematic Review and Meta-Analysis

Adding Dexmedetomidine to Intra-articular Local Anesthetics Results in Prolonged Analgesia after Knee Arthroscopy: A Systematic Review and Meta-Analysis

Tek Doz İntraartiküler Lokal Anestezik ile İnterskalen Brakiyal Pleksus Bloğunun Postoperatif Ağrı Üzerine Etkisi

Aim: Postoperative pain management is important because shoulder surgery causes severe pain. In this present study our aim was to analyse the comparison of the influences of ultrasonography-guided interscalene block and perioperative intra-articular local anesthetic injection on postoperative pain in cases who will undergo arthroscopic shoulder procedure.&#x0D; Material and Method: It was planned as a prospective randomized controlled trial. After the confirmation of the local ethical committee, our cases were randomly divided into two groups and one group (Group ISBPB) was administered general anesthesia after ultrasonography guided interscalene block. In the other group (Group LA), surgical procedure was carried out under general anesthesia and a single dose of intra-articular local anesthetic was administered peroperatively. Postoperative analgesia requirement, time, VAS scores, patient and surgeon satisfaction were registered.&#x0D; Results: We could not obtain a statistically significance between group LA and group ISBPB groups according to gender, side, comorbidity, additional procedure and age variables in the participants included in the study (p&gt;0.05). A numerically significance was observed between Group LA and Group ISBPB groups in terms of first analgesia requirement and patient satisfaction variables in the participants included in the study (p

Manipulation under local anaesthesia for idiopathic adhesive capsulitis

Adhesive capsulitis which is said to be a self limiting diseases is manipulated under anaesthesia and this process has been used to speed up the recovery of the disaese. Twenty six patients with idiopathic unilateral frozen shoulder underwent suprascapular nerve block and intraarticular local anesthesia with Methyl prednisolone acetate followed by manipulation of the glenohumeral joint and this randomized prospective clinical trial was performed in bone and joints hospital Barzulla Srinagar Kashmir. Differences in range of motion and pain were assessed before manipulation and at first week; 4th week; 8th week; 6 weeks and 12weeks. Passive range of motion increased significantly for forward flexion, abduction, external rotation, and internal rotation. There was a significant decrease in visual analogue pain (VAS) scores between initial and follow-up assessments. This technique is very simple, safe, cost effective and minimally invasive procedure for shortening the course of an apparently self-limiting disease and improves shoulder symptoms and function.

The ALOHA trial: (intra-articular local anaesthetic in hip arthroscopy)—a three-arm randomized trial comparing pre-emptive, high- and low-dose intra-articular local anaesthetic in hip arthroscopy

Abstract Pain after hip arthroscopy is variable and can be severe despite multimodal analgesia. Intra-articular local anaesthetic (IALA) may reduce acute postoperative pain after hip arthroscopy. However, neither its optimum dose nor timing of administration have been systematically evaluated. In 132 patients, a double-blinded, three-arm randomized controlled trial comparing IALA used during hip arthroscopy was conducted comparing 100 mg ropivacaine given at the end of the procedure (Group L, lose dose), 200 mg ropivacaine at the end of the procedure (Group H, high dose) and 100 mg of ropivacaine given at the beginning and end of the procedure (Group P, pre-emptive). There were no statistically significant differences between the three groups for Numerical Rating Scale-11 pain scores in the recovery room [mean (standard deviation): Group L—2.2 (1.9); Group H—2.3 (2.1); Group P—2.7 (2.5); lowest P = 0.6], or post-recovery room Visual Analogue Scale pain scores at 2, 4 and 6 h. There were also no significant differences in antiemetic usage and requirement for rescue fascia iliaca blockade between the three groups. Compared to a single 100 mg dose of ropivacaine at the end of the procedure, we were unable to demonstrate any advantage of either a higher dose IALA or a pre-emptive dose IALA when multimodal analgesia is used.

Impact of Intra-Articular Local Anesthesia Infiltration versus Femoral Nerve Block for Postoperative Pain Management in Total Knee Arthroplasty.

Background:Postoperative pain relief after total knee arthroplasty (TKA) can be attained by using several techniques such as intravenous analgesia, epidural analgesia, and peripheral nerve blocks that include femoral nerve and saphenous nerve. Several authors recommended intra-articular injection of local anesthetic (IALA) as a part of multimodal analgesia regimens for TKA instead of other techniques.Aims:The present study compares IALA technique efficacy with single-shot femoral nerve block (FNB) as part of multimodal analgesia regimen in TKA patients for postoperative pain management.Setting and Design:Perioperative care, randomized double-blind comparative study.Subjects and Methods:We recruited a total of 60 patients scheduled for unilateral total knee replacement under spinal anesthesia. Subjects were allocated randomly into two groups FNB and IALA receiving ultrasound-guided FNB and Intra-articular local anesthesia and morphine mix infiltration, respectively. Twenty-four hour postoperative morphine consumption through patient-controlled analgesia was the primary outcome measure in our study. Secondary outcome measures were pain scores, nausea and vomiting.Statistical Analysis:Chi-square test, Mann–Whitney test.Results:The amount of morphine consumed at the end of 24 h was noted to be higher in IALA group as compared to FNB (FNB − 16.03 ± 9.37 mgs; IALA − 23.60 ± 13.73 mgs P = 0.03). Visual analog score at 24 h with knee flexion was better in FNB group (FNB − 1.27 ± 1.43; IALA 2.42 ± 2.54, P = 0.04).Conclusion:FNB technique provides better analgesia in comparison to IALA for postoperative pain management in terms of PCA morphine consumption.

Negative Influence of femoral nerve block on quadriceps strength recovery following total knee replacement: A prospective randomized trial

BackgroundPostoperative pain is a major concern after total knee replacement (TKR) and can be relieved using different methods, including femoral nerve block (FNB). Quadriceps strength recovery (QSR) is the most sensitive objective indicator of functional recovery after TKR. The goal of this study was to compare the QSR following TKR between three approaches to analgesia. HypothesisFNB delays QSR at short- and mid-term follow-up. MethodsIn this prospective randomized trial, with single-blind assessment involving 135 patients admitted for TKR in an academic center, the three following groups included were: (A) Continuous FNB 48h+PCA, (B) Single-shot FNB+PCA and (C) PCA alone. No intra-articular local anesthesia was carried out for all patients. Groups were comparable for demographic and surgical data. FNB was carried out and controlled (electric stimulation) by an expert anesthesiologist prior to the surgery. Follow-up was standardized in all groups using blinded assessors. Quadriceps strength was measured using a certified dynamometer at 6 weeks, 6 months and 12 months. Multivariate analysis (Kruskal-Wallis, Mann-Whitney) was used for the main outcome. ResultsA total of 135 patients were included. Two patients in group B were excluded due to a direct fall in the first postoperative week with extensor mechanism rupture and peri-prosthetic femoral fracture. QSR was significantly decreased in patients with FNB at all times (mean±SD): 6 weeks (A: 51.3±23.3%; B: 62.2±21.9%;C: 77.4±19.5%; p<0.01), 6 months (A: 65.4±22.9%; B: 82.1±24.2%;C: 95.7±20.7%; p<0.01) and 12 months (A: 87.8±17.6%; B: 97.8±26.9%;C: 104.8±25.2%; p=0.02). No significant difference between continuous or single-shot FNB was observed. ConclusionFNB has a negative influence on QSR at short- and mid-term follow-up. FNB should not yet be recommended for analgesia after TKR. Level evidenceI High-quality randomized controlled trial with statistically significant difference.

Chondrotoxic Effects of Local Anesthetics on Human Knee Articular Cartilage: A Systematic Review.

To review the current literature on the effects of intraarticular local anesthetics on human knee articular cartilage. PubMed; MEDLINE; SCOPUS; PEDro; CINAHL databases (1/1990-06/1/2018) were searched for local anesthetic effects on human knee articular cartilage. Sixteen studies met the inclusion criteria, with outcome measures assessing chondrocyte viability, morphology, and histology. A systematic review was performed using PRISMA guidelines. Seven studies were identified evaluating lidocaine, with five of them demonstrating statistically significant chondrotoxic effects. Fourteen studies examined bupivacaine, with all but one study demonstrating a chondrotoxic effect. Eight studies examined ropivacaine and found a dose-dependent chondrotoxicity starting at 0.75%. Two studies evaluated levobupivacaine showing chondrotoxicity, with one study showing it to be more chondrotoxic than bupivacaine. One study looked at mepivacaine and showed it to have more chondrotoxicity than ropivacaine. When studied the chondrotoxicity was found to be both dose and time dependent. Also, the addition of corticosteroids appeared to worsen the chondrotoxic effects. Lidocaine, bupivacaine, ropivacaine, levobupivacaine, and mepivacaine were reported to have dose- and time-dependent deleterious effects on chondrocytes that appeared to be made worse by the coadministration of corticosteroids. Ropivacaine at concentrations of 0.5% or less was found to be the least chondrotoxic anesthetic. I.

Efectividad de la anestesia intraarticular en artroscopía de rodilla

Indroduction Knee arthroscopy is one of the most commonly performed procedures. General anesthesia and spinal blockage are the most common forms of anesthesia. We consider that this surgery can be managed with intra-articular local anesthesia, thus avoiding prolonged stays in recovery, with effective pain management and optimization of presurgical, intrasurgical and post-surgical times. Material and methods Prospective, quasi-experimental, longitudinal study to compare two anesthetic procedures: intraarticular anesthesia (lidocaine with epinephrine, bupivacaine and fentanyl) without the use of ischemia (group A); spinal blockage and use of ischemia (group B) by assessing age, surgery time, pain during surgery and 24 hour post-op VA scale, time spent in recovery, need to administer general anesthesia or anesthetic rescue doses, 24-hour range of motion. Student t-test, significance level was used: p 0.05 for nonparametric variables and 2 parametric variables. Results 38 patients were included per group. The surgical time (45 min vs 39 min, p = 0.03), recovery time (1.9 vs 3 hours, p = 0.0004) were lower in group A, while pain during surgery was greater (17 vs 3%, p = 0.09), without requiring general anesthesia. Conclusion The advantages in favor of intraarticular anesthesia were: shortened hospital stays, less pain at 24 hours, safety in its application. Its disadvantage is the possibility of pain during surgery and sedation is sufficient as adjuvant.

Efficacy of the Adductor Canal Approach to Saphenous Nerve Block for Anterior Cruciate Ligament Reconstruction With Hamstring Autograft: A Randomized Controlled Trial.

Background:For reconstruction of the anterior cruciate ligament (ACL) with hamstring autograft, perioperative analgesia can be achieved with multimodal analgesia and intra-articular local anesthesia infiltration with or without additional regional blocks. Saphenous nerve block (SNB) via the adductor canal is commonly used in our practice, but its benefit has not been well established in the literature.Purpose:To assess the efficacy of SNB in ACL reconstruction with hamstring autograft.Study Design:Randomized controlled trial; Level of evidence, 1.Methods:Consecutive patients undergoing arthroscopic ACL reconstruction with hamstring autograft were randomized into a control group (no SNB) and an intervention group (SNB). All patients received standardized anesthetic induction and maintenance agents with perioperative analgesia, per study protocol, with local anesthetic infiltration of the graft harvest site and intra-articular infiltration.Results:Sixty patients were randomized into the 2 groups (n = 30 each). There was no statistically significant difference in total opiate consumption between the groups (control, 34 mg; SNB, 31 mg; P = .40). There was no statistically significant difference in visual analog scale scores for pain at 0, 8, and 24 hours postsurgery, and no difference in overall satisfaction score. The control group had a significantly higher visual analog scale score at 4 hours postsurgery (3.0 vs 1.9, P = .04).Conclusion:SNB has a minimal effect on postsurgical care for ACL reconstruction with hamstring autograft in the presence of multimodal analgesia and local anesthetic infiltration.

Intra-articular Alpha-2 Agonists as an Adjunct to Local Anesthetic in Knee Arthroscopy: A Systematic Review and Meta-Analysis.

The infiltration of local anesthetic has been shown to reduce postoperative pain in knee arthroscopy. Several studies have shown that the addition of agents such as magnesium and nonsteroidal antiinflammatory drugs (NSAIDs) result in an increased time to first analgesia and overall reduction in pain. The aim of this systematic review and meta-analysis was to determine whether the addition of an α-2 agonist (A2A) to intra-articular local anesthetic, results in a reduction in postoperative pain. Four major databases were systematically searched for relevant randomized controlled trials (RCTs) up to July 2017. RCTs containing a control group receiving a local anesthetic and an intervention group receiving the same with the addition of an A2A were included in the review. The included studies were assessed for level of evidence and risk of bias. The data were then analyzed both qualitatively and where appropriate by meta-analysis. We reviewed 12 RCTs including 603 patients. We found that the addition of an A2A resulted in a significant reduction in postoperative pain up to 24 hours. The addition of the A2A increased time to first analgesia request by 258.85 minutes (p < 0.00001). Total 24-hour analgesia consumption was analyzed qualitatively with all included studies showing a significant reduction in total analgesia requirement. Interestingly, none of the studies found an increase in side effects associated with the A2A. This study provides strong evidence for the use of A2As as a means to reduce postoperative pain post arthroscopic knee surgery, without a corresponding increase in side effects.

Arthroscopic findings of a diagnostic dilemma- hip pathology with normal imaging

BackgroundPatients with groin, hip and pelvic pain but normal findings on MRI and minimal changes on x-ray can be a diagnostic problem. This paper looks at the arthroscopic findings of patients who have had hip pain and a positive response to an intra-articular anaesthetic but have non-contributory imaging. We hypothesized that standard MRI’s were missing significant pathology and if there was a response to intra-articular local anaesthesia, pathology found during arthroscopy was likely.MethodsA retrospective review of all hip arthroscopies performed from March 2011 to January 2015 by two orthopaedic surgeons specializing in hip arthroscopy was conducted to identify patients with clinically suspected intra-articular hip pathology despite a normal MRI report and X-ray. Clinical suspicion of intra-articular hip pathology was confirmed with a positive response to a fluoroscopically guided intra-articular injection of local anaesthetic and corticosteroid. Pathologic findings were collated from the standardised operative notes.ResultsFifty-three hip arthroscopies performed in 51 patients met the inclusion criteria from a total of 1348 hip arthroscopies performed over a 46-month period. All but one of the 53 (98%) hips had arthroscopically confirmed pathology. Mean patient age was 32.5 years [15 to 67 years] with 40 (78%) females and 11 (22%) males. 92.5% of the hips (49/53) were FADIR (flexion, adduction and internal rotation) positive on clinical examination, giving this test a positive predictive value of 98% (95% CI: 89.31 to 99.67%) for intra-articular pathology.ConclusionsIn patients with a normal MRI without contrast and a positive response (relief of pain) to an intra-articular injection that failed conservative management, there is a 98% chance of intra-articular hip pathology being discovered on hip arthroscopy.

Postoperative pain treatment after total knee arthroplasty: A systematic review.

IntroductionThe aim of this systematic review was to document efficacy, safety and quality of evidence of analgesic interventions after total knee arthroplasty (TKA).MethodsThis PRISMA-compliant and PROSPERO-registered review includes all-language randomized controlled trials of medication-based analgesic interventions after TKA. Bias was evaluated according to Cochrane methodology. Outcomes were opioid consumption (primary), pain scores at rest and during mobilization, adverse events, and length of stay. Interventions investigated in three or more trials were meta-analysed. Outcomes were evaluated using forest plots, Grading of Recommendations Assessment, Development and Evaluation (GRADE), L’Abbe Plots and trial sequential analysis.ResultsThe included 113 trials, investigating 37 different analgesic interventions, were characterized by unclear/high risk of bias, low assay sensitivity and considerable differences in pain assessment tools, basic analgesic regimens, and reporting of adverse events. In meta-analyses single and continuous femoral nerve block (FNB), intrathecal morphine, local infiltration analgesia, intraarticular injection of local anaesthetics, non-steroidal anti-inflammatory drugs, and gabapentinoids demonstrated significant analgesic effects. The 24-hour morphine-sparing effects ranged from 4.2 mg (CI: 1.3, 7.2; intraarticular local anaesthetics), to 16.6 mg (CI: 11.2, 22; single FNB). Pain relieving effects at rest at 6 hours ranged from 4 mm (CI: -10, 2; gabapentinoids), to 19 mm (CI: 8, 31; single FNB), and at 24 hours from 3 mm (CI: -2, 8; gabapentinoids), to 16 mm (CI: 8, 23; continuous FNB). GRADE-rated quality of evidence was generally low.ConclusionA low quality of evidence, small sample sizes and heterogeneity of trial designs prohibit designation of an optimal procedure-specific analgesic regimen after TKA.

Comparison of analgesic effect of intra-articular administration of levobupivacaine and clonidine versus ropivacaine and clonidine in day care knee arthroscopic surgery under spinal anesthesia

Introduction: Intra-articular (IA) local anesthetics are often used for the management and prevention of pain after arthroscopic knee surgery. Clonidine prolongs the duration of local anesthetics. In this study, analgesic effect of intra-articular administration of levobupivacaine and clonidine was compared with ropivacaine and clonidine in knee joint arthroscopic surgery under spinal anesthesia. Method: 88 patients, aged between 15 to 55 years, ASA I and II undergoing knee arthroscopy under spinal anesthesia were assigned into two equal groups (n = 44) in a randomized double blind protocol. Patients in Group L received 10 ml of 0.50% levobupivacaine and 1 mcg/kg clonidine and Group R received 10 ml of 0.75% ropivacaine and 1 mcg/kg of clonidine through intra-articular route at the end of the procedure. In the post-operative period, pain intensity was assessed by VAS (Visual Analogue Scale) Score recorded at 1 st , 5 th , 8 th , 12 th , 18 th post-operative hours. Duration of analgesia, total rescue analgesic dose in first 18 hours and any side effects were also recorded. Result: Group L experienced significantly longer duration of effective postoperative analgesia and lesser rescue analgesic compared to group R. Group R had higher mean VAS score at 5 th and 12 th post-operative hours (P < 0.05). No side effects were observed among the groups. Conclusion: Intra-articular administration of levobupivacaine and clonidine give better post-operative pain relief by increasing duration of analgesia, and decreasing need of rescue analgesic compared to intra-articular ropivacaine and clonidine.

Comparative Study of Analgesic Effects of Intraarticular Administration of Equipotent Dose of Morphine and Fentanyl with Bupivacaine and Bupivacaine alone in Arthroscopic ACL Reconstruction

Intraarticular (IA) local anesthetics and opioids are often used for the management and prevention of pain after arthroscopic anterior cruciate ligament (ACL) reconstruction. In this study, analgesic efficacy of IA administration of equipotent dose of morphine and fentanyl with bupivacaine and bupivacaine alone in arthroscopic ACL reconstruction under spinal anesthesia has been compared. Forty-five patients, aged between 15 and 55 years, of American Society of Anesthesiologists (ASA) grade I and II were assigned into three equal groups (n = 15) in a randomized double-blind protocol. Group B received 20 mL of 0.25% bupivacaine and 1 mL normal saline (NS); group BF received 20 mL of 0.25% bupivacaine and 50 μg (1 mL) fentanyl; and group BM received 20 mL of 0.25% bupivacaine and 5 mg (0.5 mL) morphine and 0.5 mL NS through IA route at the end of the procedure. Postoperative analgesia was assessed by visual analogue scale (VAS) score. The VAS score in BM group was less during all the time in the postoperative period compared with the other two groups. This group also experienced longer duration of postoperative analgesia and lesser rescue analgesic. Intraarticular administration of morphine and bupivacaine is safe and provides prolonged analgesia with minimal side effects compared with bupivacaine and fentanyl and bupivacaine alone.

Should we reconsider the use of intra-articular local anaesthetics?

Should we reconsider the use of intra-articular local anaesthetics?

Comparative effects of vitamin C on the effects of local anesthetics ropivacaine, bupivacaine, and lidocaine on human chondrocytes

BackgroundIntra-articular injections of local anesthetics are commonly used to enhance post-operative analgesia following orthopedic surgery as arthroscopic surgeries. Nevertheless, recent reports of severe complications due to the use of intra-articular local anesthetic have raised concerns. ObjectivesThe study aims to assess use of vitamin C in reducing adverse effects of the most commonly employed anesthetics – ropivacaine, bupivacaine and lidocaine – on human chondrocytes. MethodsThe chondrocyte viability following exposure to 0.5% bupivacaine or 0.75% ropivacaine or 1.0% lidocaine and/or vitamin C at doses 125, 250 and 500μM was determined by LIVE/DEAD assay and annexin V staining. Expression levels of caspases 3 and 9 were assessed using antibodies by Western blotting. Flow cytometry was performed to analyze the generation of reactive oxygen species. ResultsOn exposure to the local anesthetics, chondrotoxicity was found in the order ropivacaine<bupivacaine<lidocaine. Vitamin C effectively improved the reduced chondrocyte viability and decreased the raised apoptosis levels following exposure to anesthesia. At higher doses, vitamin C was found efficient in reducing the generation of reactive oxygen species and as well down-regulate the expressions of caspases 3 and 9. ConclusionsVitamin C was observed to effectively protect chondrocytes against the toxic insult of local anesthetics ropivacaine, bupivacaine and lidocaine.

Efficacy of Intra-articular Local Anesthetics in Total Knee Arthroplasty.

Pain management after total knee arthroplasty (TKA) remains among the most important challenges for patients with TKA. Intra-articular local anesthetic has been shown to reduce postoperative pain following TKA. However, studies report conflicting results. This meta-analysis evaluated the efficacy and safety of single-dose intra-articular local anesthetics for pain control after TKA. Databases (Cochrane Central Register of Controlled Trials, Embase, PubMed, Web of Science, and Chinese Biomedical Databases) were searched to identify randomized, controlled trials comparing local anesthetic with placebo in patients undergoing TKA. Data were extracted independently by 2 researchers using a standardized form. Risk of bias was assessed with the use of the Cochrane Collaboration's tool for assessing the risk of bias by 2 observers. Relative risk, standardized mean difference, and corresponding 95% confidence interval were calculated. Seventeen trials met the inclusion criteria, for a total of 1338 participants. The results showed that, compared with the placebo group, the single local anesthetic group had a significant lower pain score with rest at 4, 8, 24, and 48 hours; less opioid consumption at 24, 48, and 72 hours postoperatively; and greater range of motion at 24, 48, and 72 hours. There were no significant differences between the 2 groups in length of hospital stay, nausea and vomiting, pruritus, sedation, or deep venous thrombosis. The study findings showed that pain relief after TKA was significantly better with intra-articular local anesthetic than with placebo.

Management of Pain Secondary to Temporomandibular Joint Syndrome with Peripheral Nerve Stimulation

Background: Temporomandibular joint syndrome, or Costen syndrome, is a clinically diagnosed disorder whose most common symptoms include joint pain and clicking, difficulty opening the mouth, and temporomandibular joint discomfort. The temporomandibular joint (TMJ) is supplied by the auriculotemporal nerve, a collateral branch of the mandibular nerve (the V3 branch of the trigeminal nerve). Objectives: The aim of this study is to assess the effectiveness and safety of permanent peripheral nerve stimulation to relieve TMJ pain. Study Design: This case series is a prospective study. Setting: Pain Unit of a regional universitary hospital. Methods: The study included 6 female patients with temporomandibular pain lasting from 2 to 8 years that did not respond to intraarticular local anesthetic and corticoid injections. After a positive diagnostic block test, the patients were implanted with quadripolar or octapolar leads in the affected preauricular region for a 2-week stimulation test phase, after which the leads were connected to a permanent implanted pulse generator. Results of the visual analog scale, SF-12 Health Survey, Brief Pain Inventory, and drug intake were recorded at baseline and at 4, 12, and 24 weeks after the permanent implant. Results: Five out of 6 patients experienced pain relief exceeding 80% (average 72%) and received a permanent implant. The SF-12 Health Survey results were very positive for all specific questions, especially items concerning the physical component. Patients reported returning to normal physical activity and rest at night. Four patients discontinued their analgesic medication and 1 patient reduced their gabapentin dose by 50%. Limitations: Sample size; impossibility of placebo control. Conclusion: Patients affected with TMJ syndrome who do not respond to conservative treatments may find a solution in peripheral nerve stimulation, a simple technique with a relatively low level of complications. Key words: Temporomandibular joint disorder, temporomandibular joint syndrome, Costen syndrome, peripheral nerve stimulation, auriculotemporal nerve stimulation, preauricular block, clinical safety and effectiveness, trigeminal neuralgia

Effect of levobupivacaine on articular chondrocytes: an in-vitro investigation.

Intra-articular injection of local anaesthetics is a technique commonly used to enhance postoperative analgesia following arthroscopic surgery. However, the potential for cartilage damage due to toxicity of intra-articular local anaesthetics is a concern. Most studies indicate that the toxic effect is drug and time dependent. The objective of this study is to compare the in-vitro chondrotoxic effect of levobupivacaine on human cartilage with saline and bupivacaine. An experimental study. University hospital. Adult patients undergoing knee surgery. Human articular cartilage was harvested and removed from five patients during knee replacement surgery. Chondrocytes were cultured and divided into three groups exposed to bupivacaine 0.5%, levobupivacaine 0.5% or physiological saline for 15, 30 or 60 min. Viability of human cartilage cells after contact with the different study drugs at different durations of exposure using two techniques: live/dead cell viability flow cytometry analysis and trypan blue exclusion assay. At 1 h of exposure, chondrocyte mortality in cartilage explants was significantly greater after treatment with levobupivacaine or bupivacaine than with saline (25.9% ± 14.1, 20.7% ± 10.4 and 9.6% ± 5.4, respectively). No differences between groups were found when exposure to the experimental drug was limited to 15 or 30 min. In-vitro 0.5% levobupivacaine is more chondrotoxic than saline in human articular cartilage after 1 h of exposure. Bupivacaine seems to be less chondrotoxic than levobupivacaine. With shorter exposures, no clear chondrotoxic effect was shown.