Dorsal Nerve Research Articles

Effect of Selective Dorsal Neurectomy on Erectile Function in Rats

This study aimed to investigate the effect of penile selective dorsal neurectomy (SDN) on erectile function in rats. Twelve adult male Sprague-Dawley rats (15 weeks old) were divided into three groups (n=4 per group): in control group, rats received no treatment; in sham group, rats underwent a sham operation; in SDN group, rats underwent SDN with half of the dorsal penile nerve severed. The mating test was performed, and the intracavernous pressure (ICP) assessed six weeks after the surgical treatment. At postoperative six weeks, the mating test revealed no significant difference in mounting latency and mounting frequency among the three groups (P>0.05), while the ejaculation latency (EL) was significantly longer and ejaculation frequency (EF) lower in the SDN group than in the control and sham groups (P<0.05). There were no significant differences in preoperative and postoperative ICP and ICP/mean arterial blood pressure (MAP) among the three groups (P>0.05). SDN does not adversely affect the erectile function and sexual desire of rats, and at the same time it can reduce EL and EF, providing an application basis for SDN in the clinical treatment of premature ejaculation.

A279 EVIDENCE OF TRANSIENT RECEPTOR POTENTIAL MELASTATIN 3 (TRPM3) CHANNEL SENSITIZATION IN A MOUSE MODEL OF COLITIS

Abstract Background Abdominal pain is a primary symptom of inflammatory bowel disease (IBD). Opioids provide relief from IBD-associated pain, but they are addictive and associated with excess mortality in IBD patients. Thus, there is a need to develop novel therapeutics for IBD-associated pain. The mechanosensitive ion channel, transient receptor potential melastatin 3 (TRPM3) is upregulated in sensory neurons innervating inflamed tissue and contributes to pain from inflamed joints and cystitis. However, TRPM3’s role in abdominal pain has not been investigated. Purpose To evaluate whether TRPM3 contributes to abdominal pain using a mouse model of colitis. Method We used ratiometric Ca2+ imaging and extracellular afferent nerve recording to determine the effects of pharmacological activation or inhibition of TRPM3 on T13-L5 dorsal root ganglia (DRG) neurons and lumbar splanchnic nerves, respectively. Increased intracellular Ca2+ indicates neuronal excitation. Furthermore, the effects of TRPM3 activation in neurons and nerves from healthy mice and mice with dextran sulphate sodium-induced colitis were compared. Result(s) The TRPM3 agonists, CIM-0216 (0.1-10µM) and pregnenolone sulphate sodium (PSS; 1-300µM), concentration-dependently increased intracellular Ca2+ concentration in mouse DRG neurons and this was blocked using the TRPM3 inhibitor isosakuranetin (5µM; p&amp;lt;0.0001, Mann-Whitney Test). CIM-0216 (5µM)-induced increases in intracellular Ca2+ were significantly larger in neurons from mice with colitis (326±16% of baseline) compared to neurons from healthy mice (257±13% of baseline; p&amp;lt;0.01, Kruskal-Wallis with Dunn’s Multiple Comparison Test). The percentage of neurons responding to CIM-0216 was significantly increased in mice with colitis compared to healthy mice (79% vs 62%; p&amp;lt;0.001, Fischer’s Exact Test). Similarly, the percentage of neurons responding to PSS from mice with colitis was increased compared to healthy mice; however, this did not reach statistical significance (75% vs 70%, p=0.351, Fischer’s Exact Test). Furthermore, CIM-0216 (20µM)-induced change in the basal firing of lumbar splanchnic nerves was significantly increased in mice with colitis (1.23±0.24Hz) compared to healthy mice (0.60±0.14Hz, p&amp;lt;0.05, unpaired t-test). Conclusion(s) TRPM3 activation excited DRG neurons and lumbar splanchnic nerves and these excitatory effects were augmented in mice with colitis. Disclosure of Interest None Declared

Proteomic Analysis of the Spinal Dorsal Horn in Mice with Neuropathic Pain After Exercise.

Neuropathic pain (NP) is a chronic pain state with a complex etiology that currently lacks effective treatment in clinical practice. Studies have found that exercise training can alleviate NP hyperalgesia, but the specific mechanism remains unclear. Here, we sought to identify proteins and signaling pathways critical for mediating the effects of treadmill training on NP in a mouse model of spared nerve injury (SNI). We used Tandem Mass Tag (TMT) technology for proteins and signaling pathways identification. Functional enrichment analyses were conducted using DAVID and Metascape software. Ingenuity pathway analysis was used to conduct functional annotation and analyze alterations in canonical pathways and molecular networks. Reverse transcription quantitative PCR (RT-qPCR) was used to confirm the results of proteomics analysis. A total of 270 differentially expressed proteins were screened in the detrained and trained groups (P ≤0.05). Enrichment and ingenuity pathway analysis revealed the effects of treadmill training on autophagy, cAMP-mediated signaling, calcium signaling and NP signaling in dorsal horn nerves. Treadmill training reduced the expression of Akt3, Atf2, Gsk3b, Pik3c3, Ppp2ca, and Sqstm1, and increased the expression of Pik3cb in the autophagic pathway. Our results suggest that treadmill training may alleviate nociceptive hyperalgesia in NP mice by modulating the autophagic pathway, providing unique mechanistic insights into the analgesic effects of exercise.

Intracavernous injection of platelet-rich plasma reverses erectile dysfunction of chronic cavernous nerve degeneration through reduction of prostate hyperplasia evidence from an aging-induced erectile dysfunction rat model.

Age-induced erectile dysfunction (ED) is a convoluted medical condition, and restoring erectile function (EF) under geriatric conditions is highly complicated. Platelet-rich plasma (PRP) treatment is an inexpensive cell-based therapeutic strategy. We have aimed to restore EF in aged-ED rats with PRP as a therapeutic tool. Male rats were grouped into aged and young according to age. The young rats were considered as normal control (NC) and treated with saline. Aged were further divided into 2 groups and treated with intracavernous (IC) PRP and saline. Treatment was scheduled at the 9th and 10th week for NC and 41th and 42th week for aged-ED rats, with EF analysis scheduled on the 12th week for NC and 44th week for aged-ED rats, respectively. Erectile response, immunofluorescence staining, and electron microscopic analyses were performed. IC PRP treatment effectively reduced prostate hyperplasia(PH). EF response indicated a significant increase in crucial EF parameters in PRP-treated aged-ED rats. Histological evidence denoted a rigid and restored development of tunica adventitia of the dorsal artery, decreased vacuolation of the dorsal penile nerve, and structural expansion of the epineurium. Masson's trichrome and immunostaining results affirmed an elevated expression of α-smooth muscle actin(α-SMA) in the corpus cavernosum(CC). Ultrastructure findings revealed that PRP effectively rejuvenated degenerating nerves, preserved endothelium and adherent junctions of corporal smooth muscle, and restored the axonal scaffolds by upregulating neurofilament-H (NF-H)expression. Finally, PRP enhanced neural stability by enhancing the axonal remyelination processes in aged-ED rats. Hence, PRP treatment was proven to restore EF in aged-ED rats, which was considered a safe, novel, cost-effective, and hassle-free strategy for EF restoration in geriatric patients.

How many nerve fibers innervate the human glans clitoris: a histomorphometric evaluation of the dorsal nerve of the clitoris.

It is frequently quoted in mainstream media that the clitoris has "8000 nerve endings." However, no study has yet quantified the number of nerve fibers (axons) innervating the human clitoris. The dorsal nerves of the clitoris (DNCs) are the primary source of sensation and somatic clitoral innervation. Therefore, reporting the number of axons in the DNCs is an important step in our understanding of clitoral innervation and sexual response with implications for many fields of medical practice. The purpose of this study is to quantify the mean number of axons in the human DNCs and to report the approximate mean number of nerve fibers that innervate the human glans clitoris. DNC samples were obtained from 7 transmasculine patients undergoing gender-affirming phalloplasty surgery. At the time of nerve coaptation, a small excess of the DNC (5 mm) was collected for analysis at the proximal level of the clitoral body, just distal of the emergence of the DNCs from underneath the pubic symphysis. Samples were placed into 3% glutaraldehyde fixative, postfixed in 1% osmium tetroxide, and serially dehydrated in ethanol and toluene. Samples were then embedded in araldite, sectioned on an ultramicrotome into 1-μm cross sections, and counterstained with 1% toluidine blue. Histomorphometric evaluation was performed at 1000x magnification with a Leitz Laborlux S microscope and image analysis software (Clemex Vision Professional) to obtain an axon counts. Descriptive statistics were performed to yield a mean and standard deviation of the number of axons in the DNCs. Assuming anatomic symmetry between bilateral DNCs, mean total number of somatic nerve fibers innervating the human glans clitoris was obtained by doubling the mean count of the DNCs. Seven sample DNCs were collected. Of those, 5 were analyzed as 2 did not have sufficient nerve tissue present. The mean number of nerve fibers in the human DNCs was 5140 (SD = 218.4). The mean number of myelinated nerve fibers innervating the human clitoris was 10,281 (SD = 436.8). This study is the first to report the number of axons in the human DNC, at a mean 5140. Given the bilateral nature of clitoral innervation and symmetry of anatomic structures, the approximate mean number of myelinated axons that innervate the human glans clitoris is 10,280. When the uncaptured unmyelinated fibers and contributions from the cavernosal innervation are accounted for, it is clear that far Moree than 8000 axons innervate the human clitoris.

Electrical stimulation of the dorsal clitoral nerve in the treatment of idiopathic defecatory urgency. A pilot study

PurposeTo investigate the effect of dorsal clitoral nerve stimulation (DCNS) on bothersome urgency to defecate with or without fecal incontinence and the patient-reported discomfort or adverse effect with the method.MethodsFor dorsal clitoral nerve stimulation, a battery powered, handheld stimulator was used, set to a pulse width of 200 µs and a frequency of 20 Hz. One electrode was placed at the preputium of the clitoris and acted as cathode while an anode electrode was placed on the belly. Prior to stimulation the patients were asked to complete a bowel habit diary throughout 14 consecutive days before and during stimulation.ResultsFourteen out of the 16 patients included completed the study. A decrease in the number of episodes (per day) with strong urgency declined in eight patients but increased in four cases during the stimulation period. An increase in episodes with moderate or mild urgency was observed in 11 and 6 cases, respectively, and a decrease in defecation without the feeling of urgency or passive incontinence decreased in two thirds of the patients. Two patients discontinued the study prematurely, on due to worsening in symptoms and one due to pelvic pain.ConclusionAlthough the results may be promising, much still must be learned about the method including mode and duration of stimulation, better electrodes and more patient friendly equipment together with the development of better questionnaires to assess the patient burden of urgency.

Shaeer's infrapubic technique for penile prosthesis implantation through a single midline corporotomy: A single-center pilot study.

With the infrapubic approach (IPA) for penile prosthesis implantation, lateral corporotomies carry the risk of injury to the laterally coursing dorsal nerves. We sought to describe for the first time Shaeer's IPA, a modification of the IPA whereby malleable penile prosthesis cylinders are implanted through a single midline corporotomy in the bed of the deep dorsal vein, anatomically off the course of the dorsal nerves of the penis. We compared semirigid penile prosthesis implantation via the single midline corporotomy IPA (IPA-S, n = 11) to the classic IPA with laterally placed dual corporotomies (IPA-D, n = 11) and to the penoscrotal approach (PSA; n = 13). Shaeer's IPA is performed through an infrapubic incision. A 3- to 5-cm length of the deep dorsal vein is stripped. A single 3- to 5-cm midline corporotomy is cut along the bed of the vein. Dilation, sizing, and implantation are performed through the single corporotomy on either side of the midline septum. Patients are discharged the same day and are allowed to bend the implant after 2weeks and to commence intercourse after 3 weeks. Operative time, postoperative satisfaction, International Index of Erectile Function 5 (IIEF-5), and possible complications were recorded. There were no statistically significant differences in age, postimplantation IIEF-5, or satisfaction between the 3 groups. Average operative time for the IPA-S group was 21.8% shorter than that for the IPA-D group, and 34.5% shorter than for the PSA group. Those differences were statistically significant. No complications were recorded in the IPA-S group. Infection occurred in 1 PSA case, and partial hypoesthesia in 1 IPA-D case. The midline corporotomy confers an anatomical advantage that may help avoid nerve injury, thereby increasing the safety of the IPA. The main limitation of this study is the limited sample number, considering that this is a pilot study. The Shaeer's Midline-Corporotomy IPA is a minimally invasive technique for implantation of a semirigid penile prosthesis, with an anatomical advantage that may decrease the possibility of dorsal nerve injury.

Anatomical Variations in the Course and Level of Termination of Superficial Peroneal Nerve- A Cadaveric Study

Introduction: Several variations in the course and branching pattern of the Superficial Peroneal Nerve (SPN) have been reported. Knowledge of the different course of SPN is essential in reducing the risk of iatrogenic injury during the orthopaedic foot and ankle surgery and various other procedures. Aim: To observe any variations in the course, and level of termination of SPN. Materials and Methods: This descriptive analytical study was conducted on 50 lower limb specimens in the Department of Anatomy, Bangalore Medical College and Research Institute Bengaluru from January 2013 to January 2016. Dissection kit was used for dissection, digital camera was used for photography of specimens, measuring tape was used to measure the distance at which the SPN became cutaneous with respect to the tip of lateral malleolus and the distance at which SPN terminated into medial and Intermediate Dorsal Cutaneous Nerve (IDCN) with reference to the tip of lateral malleolus. Descriptive statistics was used and results were expressed as Mean±SD. Results: It was observed that the distance at which SPN became cutaneous with respect to tip of lateral malleolus was 10±2.82 cm. The level of termination of SPN into Medial Dorsal Cutaneous Nerve (MDCN) and IDCN with reference to tip of lateral malleolus was 4.7±2.08 cm. In 5 (10%) of 50 specimens the SPN terminated at a higher level before piercing the deep fascia. Out of these 5 specimens, it was observed that in one specimen the SPN terminated above the head of fibula before piercing Peroneus Longus (PL) muscle. In another specimen, the SPN terminated near the head of fibula before piercing PL muscle. In one of the specimens SPN terminated near head of fibula after piercing PL, in two specimens SPN terminated in upper third of the leg after piercing PL muscle and their terminal branches pierced the deep fascia and emerged out at different level with respect to tip of lateral malleolus. Conclusion: SPN became cutaneous and terminated in the distal third of the leg in most cases. This knowledge is very helpful to surgeons and orthopaedists in performing fasciotomy, and ankle arthroscopy to prevent iatrogenic injury to the nerve.

Ultrasound-Guided Dorsal Scapular Nerve Blockade in the Diagnosis and Management of Neck Pain

Ultrasound-Guided Dorsal Scapular Nerve Blockade in the Diagnosis and Management of Neck Pain

Low-dose caudal versus dorsal penile nerve block for postoperative analgesia after circumcision: a randomized comparative study

Low-dose caudal versus dorsal penile nerve block for postoperative analgesia after circumcision: a randomized comparative study

Identification of portals and evaluation of their safeness for MIS arthrodesis of the 1st tarsometatarsal joint

There has been a growing trend towards the use of minimally invasive surgical techniques in foot and ankle surgery. The aim of this study is to identify portal sites for minimally invasive arthrodesis of the 1st TMT joint and determine the safeness of each portal to the surrounding structures. 10 cadavers were utilized. 3 portal sites were utilized in preparing the 1st TMT joint which included dorsomedial, plantar medial and dorsolateral portals at the level of the 1st TMT joint. Fluoroscopic guided joint prep was performed. After joint prep, each specimen was dissected to evaluate structures at risk which included the deep peroneal nerve, dorsalis pedis artery, EHL Tendon, medial dorsal cutaneous nerve and medial marginal vein. In 1 specimen, there was noted to be disruption of the deep peroneal nerve, dorsalis pedis artery and partial tear of the EHL through the dorsolateral portal. No damage to any vital structures was noted at the dorsomedial or plantar medial portals. All but 1 specimen was determined to be underprepped with the dorsolateral aspect of the joint being the most common area. Additionally, upon open dissection to evaluate the joint prep, there was noted to be some small pieces of cartilage remaining despite thorough irrigation. The three-portal approach for the MIS 1st TMTJ arthrodesis is a relatively low risk procedure, with low risk of injury to the surround neurovasculature and tendon structures. However, care should be taken at each portal site with resecting cartilage to ensure no damage to surrounding vital structures occurs while also ensuring adequate joint preparation.

Clinical, Electrophysiological, and Sonographic Findings in Patients With Nerve Injury After Vessel Puncture.

This study aimed to describe the clinical, electrophysiological, and ultrasonographic findings of patients with nerve injury after vessel puncture. Data on ten patients (three males and seven females) with nerve injury after vessel puncture were reviewed. Demographic and clinical data were analyzed retrospectively. Bilateral electrophysiological studies were performed based on clinical findings. Ultrasonographic examinations were performed on both the affected and unaffected sides of the injured nerve. The nerves of nine patients were injured following vein puncture, and injury occurred following arterial sampling in one patient. Seven patients had superficial radial sensory nerve injury: five medial, one lateral, and one at both branches. One patient had injury to the dorsal ulnar cutaneous nerve, one to the lateral antebrachial cutaneous nerve, and one to the median nerve. Nerve conduction studies produced abnormal findings in 80% of patients, whereas ultrasonographic examinations produced abnormal findings in all of the patients. Spearman's coefficient for the correlation between the amplitude ratio and nerve cross-sectional area ratio was not significant, at -0.127 (95% confidence interval=-0.701 to 0.546, p=0.721). Ultrasonography supported by electrodiagnosis was found to be a useful method for identifying the lesion location and structural abnormalities of vessel-puncture-related neuropathy.

Comparing Postoperative Analgesia of Caudal and Penile Blockade using Bupivacaine in Children Undergoing Hypospadias Repair

Background &amp; Objectives: Caudal epidural and dorsal nerve penile blockade are commonly used for analgesia during and after hypospadias repair in children. Comparative studies to recommend the most effective block are in dearth. This study aims to compare penile block versus caudal block with bupivacaine for hypospadias repair in children in terms of post-operative effectiveness, pain management, and complications. Methodology: The study was conducted on 60 male children, aged 1-9 years, undergoing hypospadias surgery under general anesthesia. The subjects were randomly divided into two groups: (A: caudal block, n=30, and B: penile block, n=30). A postoperative pain assessment was conducted using FLACC scale until 24 hours post-surgery. Results: The patients from the A and B groups were comparable in age, weight, and ASA classification. All patients in the 2 groups did not feel pain post-operatively throughout the first 6 hours. One patient (3.4%) from each of the A and B groups started to feel pain 6 hours, and 9 hours, respectively after surgery. Eight patients (26.7%) in group A and 6 patients (20%) in group B felt pain throughout 6 to 24 hours after surgery. Four patients from group A and 1 patient from group B developed nausea and vomiting during the first 24 hours post-surgery. Conclusion: The penile blockade proved to be more effective in lowering postoperative pain scores, with fewer side effects, thereby decreasing the need for rescue analgesia.

Comparison and agreement between two image analysis tools for quantifying GFP::SNB-1 puncta in fshr-1 mutants of C. elegans.

Quantitative imaging of synaptic vesicle localization and abundance using fluorescently labeled synaptic vesicle associated proteins like GFP::SNB-1 is a well-established method for measuring changes in synapse structure at neuromuscular junctions (NMJ) in C. elegans . To date, however, the ability to easily and reproducibly measure key parameters at the NMJ - maximum intensity, size of GFP::SNB-1 puncta, density of puncta - has relied on the use of expensive, customizable software that requires coding skills to modify, precluding widespread access and thus preventing standardization within the field. We carried out a comparative evaluation of a new, open-source Fiji puncta plugin versus traditional Igor-based analysis of GFP::SNB-1 imaging data taken of cholinergic motor neurons in the dorsal nerve cord of loss of function mutants in fshr-1 , which encodes a G protein-coupled receptor known to impact GFP::SNB-1 accumulation. We analyzed images taken on a widefield fluorescence microscope, as well as on a spinning disk confocal microscope. Our data demonstrate strong concordance between the differences in GFP::SNB-1 localization in fshr-1 mutants compared to wild type worms across both analysis platforms (Fiji and Igor), as well as across microscope types (widefield and confocal). These data also agree with previously published observations related to synapse number and GFP::SNB-1 intensity in fshr-1 and wild type worms. Based on these findings, we conclude that the Fiji platform is viable as a method for analyzing synaptic vesicle localization and abundance at cholinergic dorsal nerve cord motor NMJs and expect the Fiji puncta plugin to be of broad utility in imaging across a variety of imaging platforms and synaptic markers.

Conservative management of penile fracture: a case report

Background: One of the uncommon emergencies in urology is a penile fracture. Due to blunt trauma to the erect penis, the tunica albuginea of one or both corpus cavernosum was disrupted, a rare kind of urologic damage. Corpus spongiosum or urethral rupture and dorsal nerve and vascular injury may also be present. Here, we describe a penile fracture case that was successfully treated conservatively at Zainoel Abidin Hospital. Case report: A 38-year-old male who had been having sex an hour before and had meatal bleeding, a history of cracking noises, and rapid detumescence presented to the emergency room at Zainoel Abidin Hospital. The patient also had pain when urinating. Physical examination revealed an enlarged penis and meatal hemorrhage but no ecchymosis or eggplant-like appearance. No bladder is full. The Foley catheter was put in. on ultrasonography of the penile. The hematoma was present in the corpus cavernous and spongiosum, and the urethra lumen was uneven. A pendulous urethral rip about 5 mm in size was found during urethroscopy. After 2 days of observation, the erectile function returned without pain or menstrual blood. After two days of conservative therapy, the patient was discharged from the hospital. Conclusion: Conservative treatment of the penile fracture is still an option based on clinical findings in cases.

Селективная криоаблация нервов полового члена в качестве метода лечения преждевременной эякуляции.

Introduction. Premature ejaculation (PE) is the second most common male sexual dysfunction with a significant negative impact on quality of life. To date, there is no satisfactory treatment for PE. Surgical methods of treatment are based on reducing the sensitivity of the glans penis by various methods, the main of which is selective dorsal neurotomy (SDN). Recently, methods have been developed for temporary demyelination of the dorsal nerve of the penis using cryoablation. This article discusses the results of selective minimally invasive cryoablation for the treatment of PE. as a treatment for premature ejaculation. Materials and methods. Materials and methods. The methods of SDN by the criablation method are described. The study involved 29 patients aged 22 to 35 years (mean age 28.7 years). All patients met the Criteria for Premature Ejaculation. Patients filled out the Premature Ejaculation Profile and recorded the time of Intravaginal Ejaculation Latency Time (IELT) before and after 3 months after SDN by cryoablation. Results. After the operation average IELT increased from of 75.8 seconds to 227.6 seconds (+298%), the average Premature Ejaculation Profile score increased from 3.6 to 11.35 points (+315%). Conclusions. Selective minimally invasive cryoablation of penile nerves is a promising treatment for premature ejaculation. However, additional studies with a larger number of participants are needed.

Safety and accuracy of blind vs. ultrasound-guided dorsal retrobulbar nerve blocks in horses-A cadaveric study.

There is limited knowledge regarding the safety and accuracy of ultrasound-guided retrobulbar nerve blocks in horses. The aim of this study was to compare these parameters between blind and ultrasound-guided injection techniques for the dorsal retrobulbar nerve block in horses. Equine cadaver heads were used to inject the retrobulbar space with contrast medium (CM). Injections were performed either blindly based on anatomic landmarks (blind group, n=44) or under ultrasonographic guidance (US-group, n=44), equally divided between an experienced and unexperienced operator. Needle position and distribution of CM were assessed with computed tomography imaging and evaluated by a board-certified veterinary diagnostic imager blinded to the technique. Safety and accuracy of both techniques were compared. Ocular penetration was observed in two cases (n=2/44) in the blind group but not in the US group (n=0/44). No intrathecal, intraneural, or intravascular injections were seen in either group. Safety was significantly improved in the US group (p=.026). There was no statistically significant difference between the groups regarding the accuracy of the injection. Excellent accuracy was achieved more often with the ultrasound-guided technique (n=11/22) than with the blind technique (n=7/22) when performed by the unexperienced operator, but this difference was not statistically significant. To prevent globe-threatening complications and improve the safety of the injection, we recommend using the ultrasound-guided injection technique for the dorsal retrobulbar nerve block.

Schwannoma of the dorsal nerve of the penis: case report and differential diagnoses

Schwannoma of the dorsal nerve of the penis: case report and differential diagnoses

Scapular winging due to rhomboid muscle paralysis: clinical assessment of 4 cases and anatomic study of the dorsal scapular nerve.

A rare cause of scapular winging is rhomboid muscle paralysis secondary to dorsal scapular nerve (DSN) neuropathy. This paralysis causes winging of the medial border of the scapula with lateral rotation of its inferior angle. We report a series of 4 clinical cases of isolated DSN compression and the results of a specific rehabilitation protocol. A continuous clinical series of 4 patients with isolated rhomboid muscle deficiency was analyzed. Two patients were men and 2 were women, with a mean age of 40years (range, 33-51years). Three patients were right-handed and 1 was left-handed. Scapular winging always affected the dominant side. Two patients had occupations involving heavy physical work. The sports practiced involved exertion of the arms (dancing, boxing, gymnastics, muscle strengthening). A specific rehabilitation protocol was offered to the patients. In addition, 6 fresh cadaver dissections were performed to reveal possible DSN compression. Potential areas of compression were identified, in particular when the arm was raised. The 4 patients presented with isolated DSN neuropathy were confirmed by electroneuromyographic testing. Total correction of scapular winging was not obtained in any patient. Three patients experienced residual pain with a neuropathic pain by the questionnaire for a Diagnosis of Neuropathic Pain (DN4) score of 2. The mean Quick-Disabilities of the Arm, Shoulder and Hand (DASH) score after treatment was 31.8 of 100. The mean ASES score was 56.2. Only 1 patient agreed to rehabilitation in a specialized center and underwent follow-up electroneuromyography. Signs of rhomboid muscle denervation were no longer present and distal motor latencies had become normal. In all cadaver dissections, the DSN originated from the C5 nerve root and did not pass through the middle scalene muscle. We identified a site of dynamic compression of the DSN by the upper part of the medial border of the scapula when the arm was raised. DSN compression is conventionally attributed to the middle scalene muscle, but it is noteworthy that our study reveals the possibility of dynamic compression of the nerve by the proximal part of the medial border of the scapula, which occurs when the arm elevation is above 90°. Our study reveals the possibility of dynamic compression of the DSN by the proximal part of the medial border of the scapula, which occurs when the arm is raised above 90°. In the absence of a surgical solution, conservative treatment is fundamental and requires management in a rehabilitation center with intervention by a multidisciplinary team.

ERECTOR SPINAE PLANE BLOCK CATHETER: A GOAL STANDARD FOR THORACIC ANAESTHESIA?

<h3>Background</h3> Recent advances in Enhanced Recovery post Thoracic surgery has introduced various fascial plane blocking techniques that block dorsal, lateral, and anterior cutaneous nerves of the thorax and abdomen. Erector spinae plane (ESP) block is a relatively novel truncal nerve plane block increasing used in thoracic analgesia. Blockage of dorsal and ventral rami of the thoracic nerves allows for effective pain management post open thoracotomies and video assisted thoracic surgery. Due to limitation by duration of action of single shot nerve blocks,(paravertebral and ESP block), continuous pain relief using catheters have been widely used with good patient outcome. <h3>Method</h3> Patients undergoing elective and urgent thoracic surgeries under general anaesthesia in a single thoracic and trauma unit in the United Kingdom were appropriately selected based on comorbidities, performance status, and indication plus duration of thoracic surgery. Retrospective data on single shot nerve block injections and patient-controlled analgesia (PCA) use was collected for fifty patients. Prospectively, ESP catheter was inserted in fifty patients by consultant anaesthetist or thoracic surgeon pre procedure and post routine intraoperative anaesthesia care and multimodal analgesia. We compared total opioid consumption, postoperative pain scores (visual analog scale), mobility with physiotherapy, complications, and length of stay. <h3>Results</h3> Forty patients were included in both groups. Five cases were removed due to incomplete data. Total opioid consumption over 24 hours and 48 hours was measured. Total opiod consumption was significantly low in patients receiving continuous ESP catheters. Pain score was lower in the recovery and post operative ward in patients with ESP catheters. Pain nurse review in ESP catheter group day 1 postoperatively allowed for better optimisation of analgesia, improved adherence to documentation of acute pain observation chart. ESP catheter did not affect physiotherapy care and patients completed 100m in less than 48 hours. There was no statistically significant difference in adverse effects between single shot vs catheter patients, however, increased PCA use in single shot blocks contributed to post operative drowsiness and nausea in five patients. <h3>Conclusion</h3> ESP catheter has shown to provide safe and effective analgesia post thoracic surgery while decreasing opioid consumption. We could demonstrate a significant improvement in patient outcome, with the ESP catheters when compared to single shot blocks. Early physiotherapy and good analgesics provided early mobilization and less days in hospital stay and reduced complications. On account of technical ease and low procedural risk of ESP block under ultrasound guidance, it is favorable for use in thoracic surgery compared to more invasive nerve blocks. More education, compliance and multimodal care is required to utilize ESP catheter for successful postoperative pain management.