C6 Dermatome Research Articles

Minimally displaced unilateral facet fracture of cervical spine can lead to spinal cord injury: a report of two cases

BackgroundAccording to most of the commonly used classification systems for subaxial spine injuries, unilateral and minimally displaced facet fractures without any sign of a spinal cord injury would be directed to non-operative management. However, the failure rate of non-operative treatment varies from 20 to 80%, and no consensus exists with regard to predictors of failure after non-operative management.Case presentationCase 1 is a patient with a unilateral facet fracture. The patient had only numbness in the right C6 dermatome but failed non-operative treatment, which resulted in severe spinal cord injury. Case 2 is a patient who had a similar injury pattern as case 1 but presented with immediate instability and underwent fusion surgery. Both patients had a minimally displaced unilateral facet fracture accompanied by disc injury and blunt vertebral artery injury, which are possible signs indicating significant instability.ConclusionsThis is the first report of an isolated unilateral facet fracture that resulted in catastrophic spinal cord injury. These two cases illustrate that an isolated minimally displaced unilateral facet fracture with disc injury and vertebral artery injury were associated with significant instability that can lead to spinal cord injury.

Post-Herpetic Brachial Plexopathy: A Rare Case Report With a Side Note on Localizing Brachial Plexopathies and a Literature Review of Post-Herpetic Segmental Paresis

We present the case of a 77-year-old man who developed shingles over the cervical C8 dermatome followed by post-herpetic medial cord brachial plexopathy, with hand weakness and difficulty performing the pinch " O " sign. This is the very first case, to our knowledge, of a detailed presentation of a medial cord plexopathy following shingles. We review the literature of post-herpetic brachial plexopathies and discuss the magnetic resonance imaging (MRI) findings of the brachial plexus in this group of patients. We also speculate on the intriguing finding that despite frequent abnormalities on MRI such as T2 signal hyperintensity and nerve hypertrophy, contrast enhancement of nerves is exceedingly rare. Furthermore, we adumbrate on the localization of brachial plexus lesions by proposing a user-friendly diagram and table, which simplifies the diagnostic algorithm.

Assessing the spatial distribution of cervical spinal cord activity during tactile stimulation of the upper extremity in humans with functional magnetic resonance imaging

Dermatomal maps are a mainstay of clinical practice and provide information on the spatial distribution of the cutaneous innervation of spinal nerves. Dermatomal deficits can help isolate the level of spinal nerve root involvement in spinal conditions and guide clinicians in diagnosis and treatment. Dermatomal maps, however, have limitations, and the spatial distribution of spinal cord sensory activity in humans remains to be quantitatively assessed. Here we used spinal cord functional MRI to map and quantitatively compare the spatial distribution of sensory spinal cord activity during tactile stimulation of the left and right lateral shoulders (i.e. C5 dermatome) and dorsal third digits of the hands (i.e., C7 dermatome) in healthy humans (n ​= ​24, age ​= ​36.8 ​± ​11.8 years). Based on the central sites for processing of innocuous tactile sensory information, we hypothesized that the activity would be localized more to the ipsilateral dorsal spinal cord with the lateral shoulder stimulation activity being localized more superiorly than the dorsal third digit. The findings demonstrate lateralization of the activity with the left- and right-sided stimuli having more activation in the ipsilateral hemicord. Contradictory to our hypotheses, the activity for both stimulation sites was spread across the dorsal and ventral hemicords and did not demonstrate a clear superior-inferior localization. Instead, the activity for both stimuli had a broader than expected distribution, extending across the C5, C6, and C7 spinal cord segments. We highlight the complexity of the human spinal cord neuroanatomy and several sources of variability that may explain the observed patterns of activity. While the findings were not completely consistent with our a priori hypotheses, this study provides a foundation for continued work and is an important step towards developing normative quantitative spinal cord measures of sensory function, which may become useful objective MRI-based biomarkers of neurological injury and improve the management of spinal disorders.

A Rare Case of Infected Cervicodorsal Intramedullary Epidermoid Cyst

Abstract Introduction Intramedullary spinal epidermoid cysts have a reported incidence of less than 1% of intramedullary spinal cord tumors; and out of these, intramedullary epidermoid lesions within the cervical spinal cord are even rarer. Here, we present the case of an adult patient with an infected intramedullary epidermoid cyst, identified on magnetic resonance imaging (MRI) at the C7–D1 level that was successfully excised without any worsening of neurological status. Case Presentation A 23-year-old female patient presented with history of moderate degree intermittent fever followed by gradually progressive right-sided weakness. She had paresthesia below C5 dermatome on the right side. On close inspection of the back, a tiny sinus opening was noted at the D2 level near the midline. MRI of the spine showed an intramedullary lesion at the C6–D1 level with the tract connecting to the subcutaneous lesion. Somatosensory evoked potential (SSEP) monitoring was done during the surgery with near total excision of the lesion. Conclusion Even though the location is rare, a differential diagnosis of the epidermoid should always be considered. A tiny dermal sinus opening helped us in proper diagnosis, along with surgical excision, by providing us a direct path to the intramedullary lesion. An early diagnosis and treatment with neurophysiological monitoring helped us in the maximum safe resection of the lesion without developing any new deficit.

Comparison of neuropathic pain characteristics associated with total brachial plexus injury before and after surgical repair: A retrospective study

ObjectivesThe goal of this study was to compare clinical characteristics of neuropathic pain associated with total brachial plexus injury before and after surgeries and to correlate possible contributing factors concerning to the pain prognosis. Patients and methodsThirty patients with both total brachial plexus injury and neuropathic pain were included. Neuropathic pain was evaluated in terms of pain intensities, symptoms and regions. Pain intensities were evaluated by a visual analogue scale. The Neuropathic Pain Symptoms Inventory questionnaire and body maps were used to compare the pain symptoms and regions. Demographic data, injury and repair information were evaluated to analyze the possible factors influencing the prognosis. ResultsThe average pain score of all participants was 7.13 ± 2.46 preoperatively and 5.40 ± 2.08 postoperatively. All patients were divided into Pain Relief Group and Pain Aggravation Group. Older age (p = 0.042), machine traction injury (p = 0.019)and nerve transplantation(p = 0.015) seemed to be related with pain aggravation. Paroxysmal pain was aggravated after surgical repairs (p = 0.041), while paresthesia/dysesthesia improved after surgery (p = 0.003). The permanent component of the pain (spontaneous pain) did not show any significant change (p = 0.584). Pain in C5 (p < 0.001) and C6 (p = 0.031) dermatomes got relieved after surgery. ConclusionThis study revealed the neuropathic pain of most patients with total brachial plexus injury was alleviated after neurosurgery, and the pain prognosis of different symptoms and regions varied after the nerve repair.

Varicella-zoster virus-induced rhabdomyolysis: A case report and literature review

Infection is a possible cause of rhabdomyolysis. We describe the case of a 63-year-old male with malaise and erythematous papules on the right C5–C7 dermatomes, consistent with herpes zoster. Serum antibody and Tzanck tests of the skin lesion were positive. Increased serum creatine kinase (CK) and myoglobin levels and cola-colored urine indicated the development of rhabdomyolysis. Acute kidney injury was also observed. After excluding other possible predisposing factors, the patient was diagnosed with varicella-zoster virus (VZV)-induced rhabdomyolysis. Extracellular volume with alkalized fluids and topical acyclovir was administered. While CK levels declined to normal by day 13, the renal function was not restored. The skin lesion crusted by day 8 and scaled off gradually by day 13. Our case and literature review highlighted the necessity for systemic antiviral treatment and that poor VZV infection control could lead to irreversible kidney injury. In addition, systemic acyclovir should be administered carefully due to its complication of nephrotoxicity.

Dermoscopy as an Important Tool for Differentiating Unilateral Nevoid Telangiectasia and Angioma Serpiginosum.

Unilateral nevoid telangiectasia (UNT) is a benign cutaneous vascular disorder, first described by Blaschko in 1899, characterized by clustered telangiectasias with a reticular appearance, blanching with diascopy, and often following a dermatomal pattern especially in C3 and C4 dermatomes, although there are reported cases without this distribution. The pathogenesis is linked mostly to estrogenic action to release nitric oxide causing capillary relaxation; this theory is supported by the predominance in female teenagers and patients with chronic liver disease presenting with this condition; however, the estrogenic role remains unclear because of the lack of receptors in skin and normal estrogen and progesterone levels in some patients with UNT [1].

Transverse Myelitis Caused by Varicella Zoster Virus

Introduction The varicella zoster virus (VZV) infection causes chickenpox and herpes zoster. Primary infection occurs more frequently in the pediatric age as chickenpox. Virus can be latent in cranial nerve or dorsal root ganglia and reactivate several decades later as the form of herpes zoster generally in immunosuppressed patients. Varicella zoster virus is associated with severe neurological complications, including post herpetic neuralgia, aseptic meningitis, polyneuropathy, cranial nerve palsy, meningoencephalitis, vasculopathy, encephalitis, and transverse myelitis. The transverse myelitis caused by VZV is reported rarely. Case Report A 77-year-old immunocompetent patient presented with muscle weakness and sensation loss due to the demyelinating lesion caused by VZV on C5 dermatome. Proprioception and vibratory sensation loss were also marked. Cervical spinal magnetic resonance imaging showed expansive intramedullary high-signal intensity lesion on C5 with focal swelling on T2-weighted images and gadalinium enhancement on T1-weighted images. cerebrospinal fluid viral antibody test was positive for immunoglobulin G of VZV but negative for VZV DNA. The patient was treated with oral valacyclovir (1 g) 3 times daily for 7 days and with methylprednisolone (1.0 g) every day for 5 days. After treatment, his muscle strength increased but sensorial loss and neuropathic pain did not recover. Conclusions About 40% of transverse myelitis cases are caused by viral infections, some of them are herpes viruses and poliovirus. Varicella zoster infection is a common disease but not a common cause of transverse myelitis particularly in immuncompetent patients. The clinicians must be aware of this rare complication of VZV.

Surgical Treatment of Traumatic Type II Odontoid Fracture Using Polyaxial C1 Lateral Mass and C2 Pedicle Screws Fixation

Background Data: Posterior atlantoaxial fixation is indicated for C1-C2 instability or painful osteoarthritis. Different techniques were designed for atlantoaxial fixation as sublaminar wiring, transarticular screw fixation, and, recently, C1 lateral mass and C2 pedicle polyaxial screws and rod system. Purpose: To investigate the safety, advantages, and complications of posterior atlantoaxial fixation with polyaxial C1 lateral mass and C2 pedicle screws in C1-C2 instability. Study Design: A retrospective clinical case series. Patients and Methods: Fourteen consecutive patients, ten males and four females, with a mean age of 40.8±9.6 years were reported. All had traumatic C1-2 instability due to type II odontoid fractures and underwent posterior fixation with polyaxial C1 lateral mass and C2 pedicle screws. Nine patients suffered from motor vehicle accident (MVA) and 5 suffered from falls. All patients were neurologically intact except four patients who had neurological deficits. We used Japanese Orthopedic Association Score (JOA) for their functional evaluation. The average follow-up was 17±1.96 (range, 12–20 months). Operative time, operative blood loss, screw trajectory, screw length, and injury of neurovascular structures were reported. Fusion and construct stability were evaluated by plain radiography and/or CT. Visual Analogue Scale (VAS) of neck pain and JOA were used to evaluate the functional outcome. Results: The mean duration of surgery was 175.3±12.3 min. The mean blood loss was 553.6±106.5 ml and two patients required transfusion of one unit of blood. The mean length of C1 lateral mass and C2 pedicle screws were 30±1.6 mm and 16.4±1.8 mm, respectively. Correct screw placement and good stability were reported in all patients (100%) at the last follow-up. Mean neck pain on VAS was 2.8±0.8 and 2.3±0.5 at 6 and 12 months, respectively. The complications included moderate pain at iliac graft site for 3 months in 2 patients, pain and dysesthesia in C2 dermatome for 4 months in 3 patients, and superficial wound infection in 2 patients. Conclusion: Posterior atlantoaxial fixation with polyaxial C1 lateral mass and C2 pedicle screws is a safe and effective method in the treatment of traumatic atlantoaxial subluxation due to type II odontoid fractures. (2019ESJ176)

(184) Feasibility of a Contact Heat Evoked Potentials Approach in Female Patients with Cerebral Palsy

Our scientific understanding of chronic pain in cerebral palsy (CP) in relation to somatosensory function is limited. There is some evidence that some individuals with CP have reduced sensitivity for non-painful touch, increased sensitivity to painful touch (pressure), and enhanced pain evoked potentials compared to controls. The goal of this pilot study was to establish initial feasibility of a contact heat approach for detecting and measuring heat-evoked potentials in CP. To reduce variance associated with gender differences, we recruited a purposeful sample of females only for the pilot (N=20, 50% CP, mean age = 20.6, range = 16-22). Six trials of 20 heat stimuli were applied to the target dermatomes for the distal volar forearm (C5 dermatome) and the distal lateral malleolus (L5 dermatome). An 11-point pain numeric rating scale (NRS) was used after each stimulus trial. Overall, initial results indicated the approach was feasible in the CP sample. All participants completed the protocol, with the exception of one CP participant. Small sample size notwithstanding, for descriptive purposes evoked potential latencies and amplitudes did not correlate with NRS ratings at either stimulation site. This is consistent with prior published findings for individuals with and without developmental disability. The NRS ratings were more variable in the CP group. A z-score proportions test was significant for arms (Z = 1.95, p

Cold evoked potentials: Acquisition from cervical dermatomes

Cold evoked potentials (CEPs) represent a novel technique to assess the integrity of cold-specific pathways within the somatosensory system. So far an objective assessment of these pathways has not been implemented into the clinical routine. Specifically, CEPs may help to elucidate the pathophysiological underpinnings of altered cold processing in neurological diseases. To test feasibility and test-retest reliability of CEPs within two cervical dermatomes, including recording sites in glabrous and hairy skin, in order to facilitate the transition into clinical practice. Twenty healthy subjects received 15 cold stimuli applied by a thermode either at the hand dorsum (C6 dermatome, hairy skin), the shoulder (C4 dermatome, hairy skin) or the thenar eminence (C6 dermatome, glabrous skin). Stimuli were applied from a baseline temperature of 30°C down to a destination temperature of 25°C at a rate of 20°C/s. N2 latencies and N2P2 amplitudes were recorded at the vertex using a surface electroencephalogram and test-retest statistics were calculated. Slight, innocuous cooling (Δ5°C) from a baseline temperature of 30°C elicited a brief percept of cooling and generated a vertex potential (N2P2) in most subjects. The latency of the vertex response is consistent with A-delta fiber activation. Based on test-retest analyses (i.e., intraclass correlation coefficients (ICCs) and Bland-Altman analyses) reliability is best within the C4 dermatome and for stimulation of hairy skin. ICCs display fair to substantial (ICCs from 0.51-0.81) reliability for amplitudes across all stimulation sites, possibly due to floor effects. CEPs latencies, however, were only poorly reliable (ICCs from -0.13 to 0.31). The acquisition of CEPs from cervical dermatomes is feasible. Since involvement of cold-specific pathways is relevant for several pathologies in clinical neurology, the application of CEPs may complement existing techniques like contact heat and laser stimulation in the assessment of peripheral and central nervous system disorders. Future studies employing different stimulation paradigms using faster cooling are warranted in order to improve the signal-to-noise ratio.

P126. Identification by ultrasound of a cervical nerve root edema caused by vertebral artery loop

Ultrasound is an excellent modality in imaging of peripheral nerves (Lawande et al., 2014; Suk et al., 2013). Although it is a well-established technique its use is not a first-line diagnostic tool in patients with brachialgias. In this case we report of a 44 years old male, who suffered for years from brachialgia of fluctuating intensity of the right arm. A lax humerus articulation of the same arm was diagnosed in the childhood and treated surgically. Actually the patient reported pain mainly in the C6 dermatome, but also shoulder area (C5). He associated these symptoms with a varicella zoster virus (VZV) affection of the shoulder some weeks ago. Cerebral spinal fluid (CSF) examination showed an altered cell count (11 cells/μL). Viral Plexus neuritis was suggested and antiviral therapy was started. Not congruent were the neurological status (Miller et al., 2000) and the electrophysiological examination of the periphery nerves, both within normal limits. The further results from the CSF suggested no acute viral infection and showed residual post infectious state with elevated IgG-Antibodies for VZV.As part of the further differential diagnosis a sonography of the cervical roots and brachial plexus was realized. It showed an edema of the cervical root C6 and in less degree of C5 and C7. Furthermore the patient had a dominant right vertebral artery (V1 diameter 5,2 mm vs. 1,9 mm of the left side) with coiling in V2-segment next to the affected roots.The MRI of the right plexus and MR-angiography confirmed the diagnosis and showed the elongated vertebral artery with a loop with contact to the affected roots.We suggest that the edema is due to the pulsatile contact of the vertebral artery, concordant to a reported intermittent pulsatile pain of the shoulder and right thumb, combined with a chronic intrathecal irritation, which explains the elevated cell count in the CFS. ConclusionThere are few case reports (Hoon Soo et al., 2010; Ahmed et al., 2014) describing a vertebral loop as origin of radiculopathy but we could not find reports of ultrasound of peripheral nerves for this diagnose. We postulate that routine ultrasound as preliminary evaluation of cervical roots and plexus of patients with brachialgias and diffuse arm pain symptoms could help to improve the diagnostic precision with this high definition and low cost methodology with no adverse events for the patients.

A low dose of three local anesthetic solutions for interscalene blockade tested by thermal quantitative sensory testing: a randomized controlled trial.

This randomized double-blind controlled trial compared the block characteristics of three low-dose local anesthetics at different roots in an ultrasound-guided interscalene block, using thermal quantitative sensory testing for assessing the functioning of cutaneous small nerve fibres. A total of 37 adults scheduled to undergo shoulder arthroscopy were randomized to receive 5mL of either 0.5% levobupivacaine with and without epinephrine 1/200,000 or 0.75% ropivacaine in a single-shot interscalene block. Thermal quantitative sensory testing was performed in the C4, C5, C6 and C7 dermatomes. Detection thresholds for cold/warm sensation and cold/heat pain were measured before and at 30min, 6, 10 and 24h after infiltration around C5. The need for rescue medication was recorded. No significant differences between groups were found for any sensation (lowest P = 0.28). At 6h, the largest differences in sensory thresholds were observed for the C5 dermatome. The increase in thresholds were less in C4 and C6 and minimal in C7 for all sensations. The analgesic effect lasted the longest in C5 (time × location mixed model P < 0.001 for all sensory tests). The time to rescue analgesia was significantly shorter with 0.75% ropivacaine (P = 0.02). The quantitative sensory findings showed no difference in intensity between the local anesthetics tested. A decrease in block intensity, with minimal changes in pain detection thresholds, was observed in the roots adjacent to C5, with the lowest block intensity in C7. A clinically relevant shorter duration was found with 0.75% ropivacaine compared to the other groups. Trial registration NCT 02691442.

Ossified extradural en-plaque meningioma of the cervical spine

A 57-year-old woman sustained gradually progressive sensorimotor disturbance in the left upper extremity for one year. Neurological examination found a diminished sensation below the left C7 dermatome and reduced strength in the left interosseous muscles. Computed tomography of the cervical spine revealed a high density mass at C7, in the left dorsal part of the spinal canal. Magnetic resonance imaging found an enhancing, en-plaque tumor at C6-T1, involving a non-enhancing part, and considerable compression of the spinal cord. The patient underwent tumor resection through hemilaminectomy of C5-C7. The tumor was located epidurally, highly fibrous including bony-hard parts, and severely adhered to the dura mater that necessitated drilling for debulking. A subtotal resection was achieved and histological diagnosis was a fibrous meningioma with metaplastic ossification. Ossification may be a pathognomonic appearance of spinal extradural meningiomas that makes resection maneuvers difficult.

Anterior head translation following cervical fusion-a probable cause of post-surgical pain and impairment: a CBP® case report.

[Purpose] To present the case of the dramatic reduction in pain, disability, and neurologic symptoms following the reduction of forward head translation and increased cervical curvature in a patient suffering from post-surgical radiculopathy. [Subject and Methods] A 52-year-old male mechanic presented with chronic neck pain, unilateral paresthesia along the C5 and C6 dermatome distributions and diminished unilateral grip strength for 12 years following a C5–C6 cervical discectomy and fusion. Outcome measures included the neck disability index, the numerical pain rating scale, and the Zebris cervical range of motion system. Radiographs and computerized posture analysis revealed excessive forward head posture. Initial traditional ‘symptom-relief’ chiropractic rehabilitation was provided, followed by CBP® structural rehabilitation of head and neck posture with a 2.5 year follow-up. [Results] The initial traditional chiropractic rehabilitation did not improve posture or disability scores. CBP methods resulted in radiograph-verified postural alignment improvements corresponding with clinically significant improvements in the patient’s neurologic condition, pain and disability scores. These results were maintained at a 2.5 year follow-up with minimal treatment. [Conclusion] Patients with post-surgical axial symptoms and/or radicular complaints should be screened for altered cervical alignment and anterior head translation. Future studies should attempt to duplicate these positive results in a trial with long-term follow-up.

Diffusely scattered macules and papules along the C5 dermatome in a 73-year-old female

Diffusely scattered macules and papules along the C5 dermatome in a 73-year-old female

Evaluation of Lung Function and Clinical Features of the Ultrasound-Guided Stellate Ganglion Block With 2 Different Concentrations of a Local Anesthetic: A Randomized Controlled Trial.

One possible complication of stellate ganglion block (SGB) is respiratory compromise. No study has yet addressed the comparison of its effect on lung function and clinical features, including Horner's syndrome, changes in temperature, sensory and motor functions, and adverse events of lower versus higher concentrations (LC and HC, respectively) of local anesthetics in an ultrasound-guided SGB. Fifty patients were randomized into 1 of 2 groups: the LC group (5 mL of 0.5% mepivacaine) and the HC group (5 mL of 1% mepivacaine). One anesthesiologist performed a C6- SGB under ultrasound guidance. Our primary objective was to compare LC and HC of a local anesthetic in terms of its effect on lung function, and the secondary objective was to compare the clinical features between LC and HC of a local anesthetic. Lung function was compared between the 2 groups using the Mann-Whitney U test. The forced vital capacity at 20 minutes post-SGB was not significantly different between the HC and the LC groups (P = .360); the median difference (95% confidence intervals [CI]) was 1 (-1 to 8). Other parameters of lung function were comparable with the forced vital capacity. Patients in the HC group had significantly greater sensory changes than those in the LC group (% decrease compared with the unblocked side); 95.4 ± 2.1 (CI: 91.11-99.73) vs 87.3 ± 3.5 (CI: 80.12-94.49). Lung function between the LC and HC groups after SGB did not differ significantly. Clinical features between the 2 groups also did not differ clinically, except that patients in the HC group had significantly greater sensory loss in the C6 dermatomes.

Long-Term Outcome of Brachial Plexus Reimplantation After Complete Brachial Plexus Avulsion Injury.

BackgroundComplete brachial plexus avulsion injury is a severe disabling injury due to traction to the brachial plexus. Brachial plexus reimplantation is an emerging surgical technique for the management of complete brachial plexus avulsion injury.ObjectiveWe assessed the functional recovery in 15 patients who underwent brachial plexus reimplantation surgery after complete brachial plexus avulsion injury with clinical examination and electrophysiological testing.MethodsWe included all patients who underwent brachial plexus reimplantation in our institution between 1997 and 2010. Patients were assessed with detailed motor and sensory clinical examination and motor and sensory electrophysiological tests.ResultsWe found that patients who had reimplantation surgery demonstrated an improvement in Medical Research Council power in the deltoid, pectoralis, and infraspinatous muscles and global Medical Research Council score. Eight patients achieved at least grade 3 MRC power in at least one muscle group of the arm. Improved reinnervation by electromyelography criteria was found in infraspinatous, biceps, and triceps muscles. There was evidence of ongoing innervation in 3 patients. Sensory testing in affected dermatomes also showed better recovery at C5, C6, and T1 dermatomes. The best recovery was seen in the C5 dermatome.ConclusionsOur results demonstrate a definite but limited improvement in motor and sensory recovery after reimplantation surgery in patients with complete brachial plexus injury. We hypothesize that further improvement may be achieved by using regenerative cell technologies at the time of repair.

The minimal effective volume (MEAV 95) for interscalene brachial plexus block for surgical anesthesia under sedation: A prospective observational dose finding study

ABSTRACTBackground: Interscalene brachial plexus (ISB) block is routinely used to provide anesthesia and analgesia for shoulder surgery. Traditional local anesthetic volumes for ISB result in near universal ipsilateral phrenic nerve paresis potentially including oxygenation and ventilation.Aims: The purpose of this study was to determine the lowest minimal effective anesthetic volume in 95% of patients (MEAV 95) of ropivacaine 0.75% for ISB that provides surgical anesthesia for arthroscopic shoulder surgery.Methods: Prospective observational cohort study in patients undergoing arthroscopic shoulder surgery under ISB (C6 level) with sedation. The dose finding protocol used the Narayana rule for up/down sequential allocation to estimate the MEAV 95 of ropivacaine 0.75%. Successful ISB was defined as complete absence of pinprick sensation in the C5 and C6 dermatomes 30 min postblock. Secondary outcomes assessed included ability to complete surgery with propofol sedation, change in slow vital capacity, room air oxygen saturation postblock, block duration, ISB complications, and numeric rating scale for pain immediately after surgery.Results: The study was stopped early due to futility. Among 225 participants approached, 54 consented to participate. The MEAV 95 for ultrasound-guided ISB of ropivacaine 0.75% for shoulder surgery was unable to be accurately estimated. Local anesthetic volumes between 5 and 20 ml did not influence any of the predefined secondary outcomes.Conclusions: The MEAV 95 (at 30 min) of ropivacaine 0.75% for ultrasound-guided ISB exceeds the local anesthetic volumes that consistently produces hemidiaphragmatic impairment. ISB cannot be guaranteed to provide surgical anesthesia at 30 min without the potential for concomitant phrenic nerve block.

Traumatic spondyloptosis of the cervical spine: A case report and discussion of worldwide treatment trends.

Background:Cervical spondyloptosis is defined as the dislocation of the spinal column most often caused by trauma. Due to compression or transection of the spinal cord, severe neurological deficits are common. Here, we review the literature and report a case of traumatic C5–6 spondyloptosis that was successfully treated using an anterior-only surgical approach.Methods:The patient presented with quadriplegia and absent sensation distal to the C5 dermatome following a rollover motor vehicle accident. The preoperative American Spinal Injury Association Impairment Scale was A. Computed tomography of the cervical spine revealed C5–6 spondyloptosis, lamina fractures on the right side at the C3–4 level, and widened facet joint on the right side at C6–7.Results:The patient underwent cervical traction and anterior cervical discectomy and fusion at the C5–6, C6–7 levels; no 360° fusion was warranted. Six months postoperatively, the patient remained quadriplegic below the C5 level.Conclusion:Presently, no consensus is present regarding the best treatment for spondyloptosis. Worldwide, the 360° approach is the most commonly used (45%), followed by anterior-only surgery (31%) and posterior-only surgery (25%). The surgical choice depends upon patient-specific features but markedly varies among geographical regions.