Ulnar neuropathy.

Ulnar neuropathy at the elbow is the second most common compressive neuropathy. Less common, although similarly disabling, are ulnar neuropathies above the elbow, at the forearm, and the wrist, which can present with different combinations of intrinsic hand muscle weakness and sensory loss. Electrodiagnostic studies are moderately sensitive in diagnosing ulnar neuropathy, although their ability to localize the site of nerve injury is often limited. Nerve imaging with ultrasound can provide greater localization of ulnar injury and identification of specific anatomical pathology causing nerve entrapment. Specifically, imaging can now reliably distinguish ulnar nerve entrapment under the humero-ulnar arcade (cubital tunnel) from nerve injury at the retro-epicondylar groove. Both these pathologies have historically been diagnosed as either "ulnar neuropathy at the elbow," which is non-specific, or "cubital tunnel syndrome," which is often erroneous. Natural history studies are few and limited, although many cases of mild-moderate ulnar neuropathy at the elbow appear to remit spontaneously. Conservative management, perineural steroid injections, and surgical release have all been studied in treating ulnar neuropathy at the elbow. Despite this, questions remain about the most appropriate management for many patients, which is reflected in the absence of management guidelines.

Assessing ulnar neuropathy at the elbow using magnetoneurography.

OBJECTIVE: To measure neuromagnetic fields of ulnar neuropathy patients at the elbow after electrical stimulation and evaluate ulnar nerve function at the elbow with high spatial resolution. METHODS: A superconducting quantum interference device magnetometer system recorded neuromagnetic fields of the ulnar nerve at the elbow after electrical stimulation at the wrist in 16 limbs of 16 healthy volunteers and 21 limbs of 20 patients with ulnar neuropathy at the elbow. After artifact removal, neuromagnetic field signals were processed into current distributions, which were superimposed onto X-ray images for visualization. RESULTS: Based on the results in healthy volunteers, conduction velocity of 30 m/s or 50% attenuation in current amplitude was set as the reference value for conduction disturbance. Of the 21 patient limbs, 15 were measurable and lesion sites were detected, whereas 6 limbs were unmeasurable due to weak neuromagnetic field signals. Seven limbs were deemed normal by nerve conduction study, but 5 showed conduction disturbances on magnetoneurography. CONCLUSIONS: Measuring the magnetic field after nerve stimulation enabled visualization of neurophysiological activity in patients with ulnar neuropathy at the elbow and evaluation of conduction disturbances. SIGNIFICANCE: Magnetoneurography may be useful for assessing lesion sites in patients with ulnar neuropathy at the elbow.

Comparison of electrodiagnostic findings in acute traumatic versus chronic non-traumatic ulnar neuropathy at the elbow.

INTRODUCTION/AIMS: A common concept is that traumatic nerve injuries are more likely axonal, and that compressive neuropathies are more likely demyelinating. The purpose of this study was to compare traumatic versus non-traumatic ulnar neuropathy at the elbow (UNE) to look for electrodiagnostic differences between the two groups. METHODS: A retrospective 3 year review of UNE patients at two academic health science centers was conducted. Patients were grouped into acute traumatic UNE versus chronic non-traumatic UNE based on clinical history. Electrodiagnostic measurements were compared between the two groups. RESULTS: There were 50 subjects with acute traumatic UNE and 41 with chronic non-traumatic UNE. Mean age and sex distribution were similar but those with traumatic UNE had a 7 month duration of symptoms, while those with chronic UNE had 29 month duration (p < .001). All electrodiagnostic measurements were similar between the two groups including compound muscle action potential amplitudes, motor conduction velocities, frequency of conduction block, sensory nerve studies, and needle electromyography. DISCUSSION: We did not find a difference between the two groups. One should not make inferences regarding acuity or etiology based on electrodiagnostic features alone.

Postoperative ulnar neuropathy: a systematic review of evidence with narrative synthesis.

BACKGROUND: Postoperative ulnar neuropathy (PUN) is an injury manifesting in the sensory or motor distribution of the ulnar nerve after anaesthesia or surgery. The condition frequently features in cases of alleged clinical negligence by anaesthetists. We performed a systematic review and applied narrative synthesis with the aim of summarising current understanding of the condition and deriving implications for practice and research. METHODS: Electronic databases were searched up to October 2022 for primary research, secondary research, or opinion pieces defining PUN and describing its incidence, predisposing factors, mechanism of injury, clinical presentation, diagnosis, management, and prevention. RESULTS: We included 83 articles in the thematic analysis. PUN occurs after approximately 1 in 14 733 anaesthetics. Men aged 50-75 yr with pre-existing ulnar neuropathy are at highest risk. Preventative measures, based on consensus and expert opinion, are summarised, and an algorithm of suspected PUN management is proposed, based upon the identified literature. CONCLUSIONS: Postoperative ulnar neuropathy is rare and the incidence is probably decreasing over time with general improvements in perioperative care. Recommendations to reduce the risk of postoperative ulnar neuropathy are based on low-quality evidence but include anatomically neutral arm positioning and padding intraoperatively. In selected high-risk patients, further documentation of repositioning, intermittent checks, and neurological examination in the recovery room can be helpful.

Compound Muscle Action Potential Amplitude as a Predictor of Functional and Patient-Reported Outcomes in Ulnar Neuropathy at the Elbow.

BACKGROUND: Ulnar neuropathy at the elbow (UNE) is a debilitating upper extremity condition that often leaves patients with residual symptoms even after surgical treatment. The role of electrodiagnostic studies in guiding the treatment of UNE is not well established, and conventional electrodiagnostic parameters may not reflect the severity of disease. Compound muscle action potential (CMAP) amplitude is a parameter that corresponds with axonal injury and motor symptoms and may more accurately predict the severity of neurologic injury. METHODS: This prospective multicenter study recruited 78 patients in the Surgery of the Ulnar Nerve project. Patients underwent electrodiagnostic testing and clinical assessment of motor and sensory function, and completed patient-reported outcome questionnaires, including the Michigan Hand Outcome Questionnaire; the Disabilities of the Arm, Shoulder and Hand questionnaire; and the Carpal Tunnel Questionnaire (CTQ). Correlations were measured among each of the electrodiagnostic parameters and outcomes and predictive models for each outcome were subsequently developed. RESULTS: Of all the electrodiagnostic parameters measured, only CMAP amplitude was predictive of scores on the Michigan Hand Outcome Questionnaire; Disabilities of the Arm, Shoulder and Hand questionnaire; CTQ function scale, and motor impairment in grip and pinch strength. None of the parameters were predictive of scores on the CTQ symptom scale or sensory impairments as measured with two-point discrimination or Semmes-Weinstein monofilament testing. CONCLUSIONS: CMAP amplitude, but not other conventional electrodiagnostic parameters, is predictive of functional outcomes in UNE. This electrodiagnostic measurement can alert the clinician to severe cases of UNE and inform surgical decision-making. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Electrodiagnostic Predictors of Outcomes After In Situ Decompression of the Ulnar Nerve.

PURPOSE: Patients with severe ulnar neuropathy at the elbow frequently experience suboptimal surgical outcomes. Clinical symptoms alone may not accurately represent the severity of underlying nerve injury, calling for objective assessment tools, such as electrodiagnostic studies. The goal of our study was to determine whether specific electrodiagnostic parameters can be used to predict the outcomes after in situ decompression of the ulnar nerve. METHODS: This prospective study enrolled consecutive patients aged ≥18 years diagnosed with ulnar neuropathy at the elbow. Patients completed a baseline battery of motor, sensory, functional, and electrodiagnostic tests before undergoing in situ decompression of the ulnar nerve. They were reassessed at 6 weeks, 3 months, 6 months, and 12 months after surgery. Forty-two patients completed at least 2 follow-up assessments and were included in the study. RESULTS: When controlling for other electrodiagnostic measurements and demographic factors, none of the electrodiagnostic parameters were predictive of outcomes at 12 months after surgery. Patients with decreased compound muscle action potential amplitudes demonstrated slower trends of recovery in grip strength, pinch strength, and overall scores on the Michigan Hand Outcomes Questionnaire as well as its function, work, and activities of daily living subscales, Disabilities of the Arm, Shoulder, and Hand questionnaire, and the Carpal Tunnel Questionnaire. Decreased motor nerve conduction velocity was predictive of slower recovery of 2-point discrimination and pinch strength. CONCLUSIONS: Compound muscle action potential amplitude, but not other conventional electrodiagnostic parameters, was predictive of functional outcomes after in situ decompression of the ulnar nerve. This parameter should play a role in determining the timing and prognosis of treatment for ulnar neuropathy at the elbow. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.

Evaluation of neurological testing for hand-arm vibration syndrome.

BACKGROUND: The neurological component of hand-arm vibration syndrome (HAVS) uses the Stockholm Workshop Scale sensorineural (SWS SN) stages for classification. Proximal compressive neuropathies are common in HAVS and the symptoms are similar to SN HAVS. The SWS may not be a valid staging tool if a patient has comorbid proximal compression neuropathy. AIMS: To evaluate the prevalence of proximal compression neuropathy in patients presenting for HAVS assessment and examine the association between compressive neuropathies and SWS SN. METHODS: A standardized assessment protocol was used to assess 431 patients for HAVS at St. Michael's Hospital, Toronto, Ontario. The prevalence of median and ulnar compressive neuropathies was determined. The association between proximal compression neuropathies and SWS SN stage (0/1 versus 2/3) was evaluated using Chi-square and Fisher's exact tests as well as multivariable logistic regression. RESULTS: Most patients (79%) reported numbness and 20% had reduced sensory perception (SWS SN Stage 2/3). Almost half (45%) had median neuropathy at the wrist and 7% had ulnar neuropathy. There was no association between the SWS SN stage and median or ulnar neuropathy. CONCLUSIONS: Two neurological lesions should be investigated in patients presenting for HAVS assessment: compressive neuropathy and digital neuropathy. The prevalence of compressive neuropathies is high in patients being assessed for HAVS and therefore nerve conduction studies (NCS) should be included in HAVS assessment protocols. Comorbid proximal neuropathy does not affect the SWS SN stage; therefore, NCS and SWS SN seem to be measuring different neurological outcomes in HAVS patients.

A Three months Electrodiagnostic Follow-Up of Patients Suspected of having Ulnar Nerve Involvement at Elbow Level with Normal Conventional Electrodiagnostic Study at First Evaluation.

Background: Compression of ulnar nerve at the elbow is the second most common peripheral neuropathy of the upper extremity. Objective: Due to the lack of the gold diagnostic standard for ulnar nerve involvement at elbow level (UNE) and the lack of sufficient study in this field, we decided to evaluate patients with symptoms of this disease who have normal conventional electrodiagnostic study (EDX) in first evaluation. Materials and Methods: In this cross-sectional study, 18 persons were selected from patients who were referred to the clinic of Physical Medicine and Rehabilitation. If conventional EDX was normal, compound nerve action potential (CNAP) test (peak latency and amplitude) was carried out. Patients with normal conventional EDX but abnormal ulnar CNAP included to our study. After 3 months, if they had not been treated for ulnar neuropathy, they were reexamined by conventional EDX plus ulnar CNAP measurement. Results: In total, 18 patients (11 females, 7 males) aged 28-58 years old (mean = 40.11) were analyzed in this study. After 3 months, 14 patients (77.8%) demonstrated parameter changes consistent with UNE in conventional EDX. Conclusion: Based on the results of this study, ulnar CNAP has diagnostic value in patients with symptoms of UNE who have normal routine EDX. Therefore, ulnar CNAP should be taken into account for early diagnosis of ulnar neuropathy when routine electrodiagnostic tests are normal.

Anterior interosseous nerve neuropathy in a patient with spinal cord injury: case report and literature review.

INTRODUCTION: Entrapment neuropathies, typically carpal tunnel syndrome and ulnar neuropathy, frequently occur in patients with spinal cord injury (SCI). Upper limb impairments due to entrapment neuropathy can be particularly debilitating in this population. Anterior interosseous nerve (AIN) neuropathy has not been previously described in the SCI population. CASE PRESENTATION: A 27-year-old left-handed man with a history of C7 ASIA Impairment Scale B spinal cord injury five years prior presented to clinic with decreased left thumb function as well as thumb flexion. Workup including nerve conduction studies, electromyogram, ultrasonographic assessment, and magnetic resonance neurography was consistent with compressive AIN neuropathy. Surgical exploration and neurolysis was performed, with improvement of symptoms. DISCUSSION: Entrapment neuropathies should be carefully considered in the evaluation of patients with SCI with new motor deficits. We report a case of AIN neuropathy in a patient with SCI successfully treated with surgical decompression, and review the literature describing upper extremity entrapment neuropathies in this population. Surgical decompression is an effective option for treatment of AIN neuropathy in the setting of SCI, though further characterization of the optimal management strategy is needed.

Cutaneous silent period in ulnar neuropathy at the elbow.

INTRODUCTION/AIMS: The cutaneous silent period (CSP) reflects the function of A-delta sensory fibers. There are few studies on CSP in nerve entrapment syndromes. This study aims to evaluate the neurophysiological abnormalities of small-diameter sensory fibers in ulnar neuropathy at the elbow (UNE) by means of CSP. METHODS: We consecutively evaluated UNE patients at one electrodiagnostic laboratory. The CSP was obtained upon stimulating the fifth (D5) and third digits, recording from the first dorsal interosseous (FDI) and abductor pollicis brevis (APB) muscles. RESULTS: We enrolled 37 UNE patients (mean age 55.4 ± 11.2 y) and 30 controls (mean age 51.2 ± 11.1 y). The combinations of the D5-APB and D5-FDI mean onset latencies of CSP were significantly more prolonged in patients (83.7 ± 6.8 and 84.5 ± 8 ms, respectively) than in controls (78.2 ± 8.1 and 79.4 ± 7.6 ms, respectively). The D5-FDI duration of CSP was shorter in patients (52.2 ± 8.3 ms) than in controls (55.8 ± 7 ms). The mean of the onset latencies of D5-FDI and D5-APB was related to the clinical severity (P = .013 and .0025, respectively). D5-APB and D5-FDI onset latencies were more prolonged and the duration was shorter in the UNE group with absent ulnar sensory nerve action potentials (SNAPs) and axonal motor damage than in patients with preserved SNAPs and with demyelinating damage. DISCUSSION: CSP was able to demonstrate abnormalities of small-diameter myelinated sensory fibers. This damage was directly related to UNE severity and to axonal damage of motor fibers. Absence of a sensory large-diameter fiber response did not exclude preserved residual small fiber conduction.

Diagnostic values of conventional conduction parameters in ulnar neuropathy at elbow.

BACKGROUND AND PURPOSE: Conventional parameters used in electrodiagnosis of ulnar neuropathy at elbow (UNE) are: (i) absolute across-elbow ulnar nerve motor conduction velocity (MCV), (ii) reduction rate of composed muscle action potential (CMAP) amplitude from above to below elbow stimulation, and (iii) MCV difference between forearm and across-elbow segment. We aimed to search the diagnostic accuracy values of these parameters on UNE, and their correlations with axonal dysfunction of ulnar nerve fibers. METHODS: Arms with clinical signs of UNE and two-fold healthy controls were included. We detected the best cut off points of the measured parameters and their possible combinations. Their diagnostic accuracy values and correlations with parameters reflecting the axonal functions were analyzed, statistically. RESULTS: Totally, 118 arms with UNE and 236 controls were included. Absolute across-elbow MCV yielded a higher accuracy than MCV difference and reduction rate of CMAP amplitude (p = 0.010 and p˂0.001, respectively). Besides, combining it with other parameters did not increase the diagnostic yield. Correlation analyses revealed that the only parameter having positive linear correlations with sensory nerve action potential amplitudes both in the control and the disease groups is the absolute across-elbow MCV. The absolute across-elbow MCVs have also positive linear correlation with CMAP amplitudes in disease group. CONCLUSION: The absolute across-elbow MCV is the most valuable conventional parameter for the electrodiagnosis of UNE. It is also the most correlated parameter with the electrodiagnostic parameters reflecting the axonal functions of the ulnar nerve fibers.

The red flags of ulnar neuropathy in leprosy.

The diagnosis of pure neural leprosy is more challenging because patients share characteristics with other common pathologies, such as ulnar compression, which should be taken into consideration for differential diagnosis. In this study, we identify ulnar nerve conduction characteristics to aid in the differential diagnosis of ulnar neuropathy (UN) in leprosy and that of non-leprosy etiology. In addition, we include putative markers to better understand the inflammatory process that may occur in the nerve. Data were extracted from a database of people affected by leprosy (leprosy group) diagnosed with UN at leprosy diagnosis. A non-leprosy group of patients diagnosed with mechanical neuropathy (compressive, traumatic) was also included. Both groups were submitted to clinical, neurological, neurophysiological and immunological studies. Nerve enlargement and sensory impairment were significantly higher in leprosy patients than in patients with compressive UN. Bilateral impairment was significantly higher in the leprosy group than in the non-leprosy group. Leprosy reactions were associated to focal demyelinating lesions at the elbow and to temporal dispersion (TD). Clinical signs such as sensory impairment, nerve enlargement and bilateral ulnar nerve injury associated with eletrodiagnostic criteria such as demyelinating finds, specifically temporal dispersion, could be tools to help us decided on the best conduct in patients with elbow ulnar neuropathy and specifically decide if we should perform a nerve biopsy for diagnosis of pure neural leprosy.

Treatment related fluctuation and response to intravenous immunoglobulin therapy in post COVID-19 Guillain-Barre syndrome.

Treatment related fluctuation (TRF) poses a special challenge in the treatment of Guillain-Barre syndrome (GBS). Many cases of GBS following COVID-19 infection have been reported in literature till date, but treatment related fluctuation (TRF) in post COVID-19 GBS has not been reported till date. We report a 35-year-old male patient who developed GBS following COVID-19 infection and had TRF after intravenous immunoglobulin (IV-IG) therapy. He required ventilator support but repeat IV-IG therapy led to complete recovery. Significant proximal muscle involvement, cranial nerve palsy, no antecedent diarrhea and absence of anti-GM1 antibodies are important predictors of TRF in GBS and need to be recognized early in the course of this illness. Early recognition of TRF and differentiating it from other forms of immune mediated neuropathy such as acute onset chronic inflammatory demyelinating polyradiculoneuropathy (A-CIDP) are important for prognostication and management.

Expert consensus on the combined investigation of ulnar neuropathy at the elbow using electrodiagnostic tests and nerve ultrasound.

The addition of ultrasound (US) to electrodiagnostic (EDX) tests can significantly enhance the accuracy of testing for ulnar neuropathy at the elbow (UNE). We aimed to obtain expert consensus to guide clinicians on the combined use of EDX and US in UNE investigation. Consensus was achieved using the Delphi method. Two consecutive anonymised questionnaires were submitted to 15 experts, who were asked to choose their level of agreement with each statement. Consensus was pre-defined as ≥ 80% rating agreement. The experts concluded that all investigations of UNE should include both nerve conduction studies and US. There was consensus that US should include cross-sectional area measurement and assessment of nerve mobility at the elbow, and that the entire ulnar nerve should be imaged. This study defined expert opinion on the 'core' techniques that should be used routinely in the UNE investigation using EDX and US. Areas with lack of consensus highlighted some controversial issues in the current use of these diagnostic modalities and the need for future research. This document is an initial step to guide clinicians on the combined investigation of UNE using EDX and US, to be regularly updated as new research emerges.

Determining the utility of minimum F-wave latency alterations in the electrodiagnosis of ulnar neuropathy at the elbow.

BACKGROUND: Ulnar neuropathy at the elbow (UNE) is the second most common entrapment neuropathy. There is little information about the application of F-wave studies for evaluation of UNE. OBJECTIVE: The aim of this study was to evaluate the diagnostic value of minimum F-wave (F-min) latency alterations by comparing this with nerve conduction analyses in UNE-suspected patients. METHODS: Ninety-four UNE-suspected patients were admitted to this study. Sensory and motor nerve conduction and F-wave analyses on the median and ulnar nerves were performed on both upper extremities. RESULTS: A total of 188 upper extremities of 94 patients were examined. Their mean age was 41.4±12.9 years, and 69 patients were female (73.4%). The mean ulnar-nerve across-elbow motor conduction velocity (MCV) in the affected arms was significantly slower than the velocity in healthy arms. The mean ulnar-nerve F-min latencies were significantly longer in the affected arms. Fifty-one patients were electrophysiologically diagnosed as presenting UNE (54.2%). Significantly slower mean ulnar-nerve across-elbow MCV, longer mean ulnar-nerve F-min latency and longer distal onset latency were detected in UNE-positive arms. Lastly, patients who were symptomatic but had normal nerve conduction were evaluated separately. Only the mean ulnar F-min latency was significantly longer in this group, compared with the healthy arms. CONCLUSION: Our study confirmed the utility of F-min latency measurements in the electrodiagnosis of UNE. F-wave latency differences can help in making an early diagnosis to provide better treatment options.

Electrodiagnostic Testing for Disorders of Peripheral Nerves.

Nerve conduction studies and electromyography are useful diagnostic tools that neurologists use to diagnose diseases of the peripheral nerves, neuromuscular junction, and muscles. These tests are considered an extension of clinical history and examination, and their results should always be interpreted with the clinical context. Neuromuscular diseases are common and affect a large proportion of the elderly population. With an aging population in expansion, these diseases are expected to become even more prevalent. It is important to highlight the basics of electrophysiology and provide a reference for providers who are planning to send their patients to electromyographers for these studies.V.

Marinacci anastomosis (reverse Martin-Gruber anastomosis): A case report.

RATIONALE: The incidence of Martin-Gruber anastomosis ranges from 5% to 34%, which is characterized by crossing over from the median to the ulnar nerve and innervating the first dorsal interosseous, thenar or hypothenar muscles. However, the reverse Martin-Gruber anastomosis, or Marinacci anastomosis, is far less discussed and appears in recent literature. PATIENT CONCERNS: A 56-year-old man presented to the clinic of a university hospital because of left neck soreness with numbness radiating to the left lateral shoulder. The neck discomfort was aggravated while the neck rotated or tilted to the right. DIAGNOSIS: Higher compound muscle action potential over the abductor pollicis brevis on elbow stimulation than on the wrist was found during upper limb nerve conduction velocity study. Ulnar to median anastomosis was identified. INTERVENTION: We performed cervical spine X-ray and electrophysiological examinations and monitored the patient. OUTCOMES: We identified that this patient had left C5 and C6 subacute radiculopathy with active denervation and left subclinical ulnar sensory neuropathy, and verified the existence of ulnar-to-median anastomosis. LESSONS: We demonstrated a pure motor ulnar-to-median anastomosis without sensory correspondence and higher CMAP over the abductor pollicis brevis on elbow stimulation of the ulnar nerve than on the wrist. The prevalence might be underestimated in a Chinese population-based published study.

Determining the utility of minimum F-wave latency alterations in the electrodiagnosis of ulnar neuropathy at the elbow / Determinação da utilidade das alterações mínimas da latência da onda F no eletrodiagnóstico da neuropatia ulnar do cotovelo

ABSTRACT Background: Ulnar neuropathy at the elbow (UNE) is the second most common entrapment neuropathy. There is little information about the application of F-wave studies for evaluation of UNE. Objective: The aim of this study was to evaluate the diagnostic value of minimum F-wave (F-min) latency alterations by comparing this with nerve conduction analyses in UNE-suspected patients. Methods: Ninety-four UNE-suspected patients were admitted to this study. Sensory and motor nerve conduction and F-wave analyses on the median and ulnar nerves were performed on both upper extremities. Results: A total of 188 upper extremities of 94 patients were examined. Their mean age was 41.4±12.9 years, and 69 patients were female (73.4%). The mean ulnar-nerve across-elbow motor conduction velocity (MCV) in the affected arms was significantly slower than the velocity in healthy arms. The mean ulnar-nerve F-min latencies were significantly longer in the affected arms. Fifty-one patients were electrophysiologically diagnosed as presenting UNE (54.2%). Significantly slower mean ulnar-nerve across-elbow MCV, longer mean ulnar-nerve F-min latency and longer distal onset latency were detected in UNE-positive arms. Lastly, patients who were symptomatic but had normal nerve conduction were evaluated separately. Only the mean ulnar F-min latency was significantly longer in this group, compared with the healthy arms. Conclusion: Our study confirmed the utility of F-min latency measurements in the electrodiagnosis of UNE. F-wave latency differences can help in making an early diagnosis to provide better treatment options.

RESUMO Introdução: A neuropatia ulnar do cotovelo (NUC) é a segunda neuropatia por encarceramento mais comum. Existem poucas informações sobre a aplicação dos estudos da onda F para avaliação da NUC. Objetivo: O objetivo deste estudo foi avaliar o valor diagnóstico das alterações mínimas de latência da onda F (F-min), comparando-as com análises de condução nervosa em pacientes com suspeita de NUC. Métodos: Noventa e quatro pacientes com suspeita de NUC foram admitidos neste estudo. A condução nervosa sensitiva e motora e as análises da onda F nos nervos mediano e ulnar foram realizadas em ambas as extremidades superiores. Resultados: Um total de 188 membros superiores de 94 pacientes foi examinado. A média de idade foi 41,4±12,9 anos e 69 pacientes eram do sexo feminino (73,4%). A velocidade de condução motora média do nervo ulnar através do cotovelo (VCM) nos braços afetados foi significativamente mais lenta do que a velocidade em braços saudáveis. As latências médias F-min do nervo ulnar foram significativamente mais longas nos braços afetados. Cinquenta e um pacientes foram diagnosticados eletrofisiologicamente como apresentando NUC (54,2%). Pacientes com presença de NUC tiveram, de forma significativa, detecção de VCM mais lenta no nervo ulnar ao nível do cotovelo, presença de latência mais longa da onda F-mínima no nervo ulnar, bem como latência de início distal mais longa. Por fim, os pacientes sintomáticos, e com condução nervosa normal, foram avaliados separadamente. Apenas a latência da onda F mínima média do nervo ulnar foi significativamente maior neste grupo, em comparação com os braços saudáveis. Conclusão: Nosso estudo confirmou a utilidade das medidas de latência da onda F-mínima no eletrodiagnóstico da NUC. As diferenças de latência da onda F podem ajudar a fazer um diagnóstico precoce para fornecer melhores opções de tratamento.

Perioperative Ulnar Neuropathy: A Contemporary Estimate of Incidence and Risk Factors.

BACKGROUND: Retrospective and prospective studies 2 decades ago from the authors' institution reported the incidence of perioperative ulnar neuropathy persisting for at least several months in a noncardiac adult surgical population to be between 30 and 40 per 100,000 cases. The aim of this project was to assess the incidence and explore risk factors for perioperative ulnar neuropathy in a recent cohort of patients from the same institution using a similar definition for ulnar neuropathy. METHODS: We performed a retrospective incidence and case-control study of all adults (≥18 years) undergoing noncardiac procedures with anesthesia services between 2011 and 2015. Each incident case of persistent ulnar neuropathy within 6 months of surgery was matched by age, sex, procedure date, and procedure type to 5 surgical patient controls. For the case-control study, separate conditional logistic regression analyses were performed to assess specific risk factors including the patient's body position and arm position, as well as body mass index (BMI), surgical duration, and selected patient comorbidities. RESULTS: Persistent ulnar neuropathy of at least 2 months duration was found in 22 of 324,124 anesthetics for patients who underwent these procedures during the study period for an incidence rate of 6.8 (95% confidence interval [CI], 4.3-10.3) per 100,000 anesthetics. The incidence of ulnar neuropathy was higher in men compared to women (10.7 vs 3.0 per 100,000; P = .016). From the matched case-control study, the odds of ulnar neuropathy increased with higher BMI (odds ratio [OR] = 1.67 [1.16-2.42] per 5 kg/m2 increase in BMI; P = .006), history of cancer (OR = 6.46 [1.64-25.49]; P = .008), longer procedures (OR = 1.53 [1.18-1.99] per hour; P = .001), and when 1 or both arms were tucked during surgery (OR = 6.16 [1.85-20.59]; P = .003). CONCLUSIONS: The incidence of persistent perioperative ulnar neuropathy observed in this study was lower than the incidence reported 2 decades ago from the same institution and using a similar definition for ulnar neuropathy. Several of the previously reported risk factors continue to be associated with the development of persistent perioperative ulnar neuropathy, providing ongoing targets for practice changes that might further decrease the incidence of this problem.