Ulnar Neuropathy At The Elbow Research Articles

Core outcomes in nerve surgery: development of a core outcome set for ulnar neuropathy at the elbow.

Ulnar neuropathy at the elbow (UNE) is common, affecting 1%-6% of the population. Despite this, there remains a lack of consensus regarding optimal treatment. This is primarily due to the difficulty one encounters when trying to assess the literature. Outcomes are inconsistently reported, which makes comparing studies or developing meta-analyses difficult or even impossible. Thus, there is a need for a core outcome set (COS) for UNE (COS-UNE) to help address this problem. The objective of this study was to utilize a modified Delphi method to develop COS-UNE. A 5-stage approach was utilized to develop COS-UNE: stage 1, consortium development; 2, literature review to identify potential outcome measures; 3, Delphi survey to develop consensus on outcomes for inclusion; 4, Delphi survey to develop definitions; and 5, consensus meeting to finalize the COS and definitions. The study followed the Core Outcome Set-STAndards for Development (COS-STAD) recommendations. The Core Outcomes in Nerve Surgery (COINS) Consortium comprised 21 participants, all neurological surgeons representing 11 countries. The final COS-UNE consisted of 22 data points/outcomes covering the domains of demographic characteristics, diagnostics, patient-reported outcomes, motor/sensory outcomes, and complications. Appropriate instruments, methods of testing, and definitions were set. The consensus minimum duration of follow-up was 6 months, with the consensus optimal timepoints for assessment identified as preoperatively and 3, 6, and 12 months postoperatively. The authors identified consensus data points/outcomes and also provided definitions and specific scales to be utilized to help ensure that clinicians are consistent in their reporting across studies on UNE. This COS should serve as a minimum set of data to be collected in all future neurosurgical studies on UNE. The authors hope that clinicians evaluating ulnar neuropathy will incorporate this COS into routine practice and that future studies will consider this COS in the design phase.

Chapter 2 - The role of imaging in focal neuropathies

Electrodiagnostic testing (EDX) has been the diagnostic tool of choice in peripheral nerve disease for many years, but in recent years, peripheral nerve imaging has been used ever more frequently in daily clinical practice. Nerve ultrasound and magnetic resonance (MR) neurography are able to visualize nerve structures reliably. These techniques can aid in localizing nerve pathology and can reveal significant anatomical abnormalities underlying nerve pathology that may have been otherwise undetected by EDX. As such, nerve ultrasound and MR neurography can significantly improve diagnostic accuracy and can have a significant effect on treatment strategy. In this chapter, the basic principles and recent developments of these techniques will be discussed, as well as their potential application in several types of peripheral nerve disease, such as carpal tunnel syndrome (CTS), ulnar neuropathy at the elbow (UNE), radial neuropathy, brachial and lumbosacral plexopathy, neuralgic amyotrophy (NA), fibular, tibial, sciatic, femoral neuropathy, meralgia paresthetica, peripheral nerve trauma, tumors, and inflammatory neuropathies.

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

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. 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. 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. We did not find a difference between the two groups. One should not make inferences regarding acuity or etiology based on electrodiagnostic features alone.

Diagnosis of Ulnar Neuropathy at the Elbow Using Ultrasound — A Comparison to Electrophysiologic Studies

Given the relatively high false negative rate of electrodiagnostic studies (EDX) in patients with clinically diagnosed ulnar neuropathy at the elbow (UNE), we sought to determine whether an alternative objective test could more effectively detect UNE. Additionally, we proposed to determine the relationship between the cross-sectional area (CSA) of the ulnar nerve on ultrasound(US), EDX, and clinical symptoms. This was a retrospective study of patients presenting with symptomatic UNE. The performance characteristics of EDX versus ultrasound were calculated using the clinical diagnosis of UNE as the reference standard. Standard EDX studies and US of the ulnar nerve were analyzed. Maximal CSA of the ulnar nerve and EDX severity were analyzed for patients with each combination of US-positive/negative and EDX-positive/negative findings. Analysis was performed on 89 patients and 115 nerves with signs and symptoms of cubital tunnel syndrome. In total, 56 (49%) nerves were diagnosed as mild UNE, 32 (28%) nerves were diagnosed as moderate UNE, 17 (15%) nerves were diagnosed as severe UNE, and 10 (8%) nerves were negative for UNE by EDX. Maximal-maximal CSA was highly correlated with disease severity as determined by nerve conduction studies/electromyography. Compared with EDX+/US+, patients with EDX-/US+ showed higher rates of ulnar sensory loss and elbow tenderness with similar rates of positive Tinel and intrinsic muscle atrophy. In this sample of patients with clinically diagnosed UNE, 91.3% of the patients demonstrated positive EDX studies, whereas 94.8% had a positive US. Ultrasound is an alternative to EDX that could be incorporated clinically in the diagnosis and management of UNE. Ultrasound was able to consistently detect clinically positive cubital tunnel syndrome demonstrating its utility as a confirmatory or supplemental test to the clinical assessment if one is required. Ultrasound additionally may be able to better identify patients with early stages of UNE with negative EDX findings. Diagnostic IV.

Clinical and neurophysiological recovery of ulnar nerve conduction block at the elbow.

An important mechanism of peripheral nerve motor and sensory dysfunction is conduction block (CB). However, recovery from mechanically induced CB has been rarely studied in humans. The aim of this study was to describe clinical, electrodiagnostic (EDx), and ultrasonographic (US) characteristics of CB recovery in ulnar neuropathy at the elbow (UNE). We recruited a group of consecutive patients presenting to our EDx laboratory with UNE and >50% motor CB. Patients' histories were obtained and neurologic, EDx, and US examinations were repeated every 1-3 mo for at least 12 mo. We studied 10 patients (5 men), with a mean age of 63 y (range, 51-81 y). In all affected arms CB was localized to the retrocondylar groove. Following conservative management, myometrically measured index finger abduction improved from a median of 49% to 100% relative to the contralateral index finger, and ulnar nerve CB decreased from a median of 74% to 6%. Most of the improvement took place within 8 mo of symptom onset, and 6 mo after receiving treatment instructions. Mean motor nerve conduction velocity improved from 15 to 27 m/s in the most affected 2-cm ulnar nerve segment. The resolution of CB after typical chronic compression may take longer than after acute compression. This should be considered by clinicians when estimating prognosis for discussions with patients.

No Major Nerve Regeneration Seems to Occur during Recovery of Ulnar Neuropathy at the Elbow.

Introduction: There are three main potential mechanisms of recovery after nerve lesion: (1) resolution of conduction block, (2) collateral reinnervation, and (3) nerve regeneration. Their relative contributions in recovery after focal neuropathies are not well established. Methods: In a group of previously reported prospective cohort of patients with ulnar neuropathy at the elbow (UNE), I performed a post-hoc analysis of their clinical and electrodiagnostic findings. I compared amplitudes of the compound muscle action potential (CMAP) and sensory nerve action potential (SNAP) on ulnar nerve stimulation, as well as qualitative concentric needle electromyography (EMG) findings in the abductor digiti minimi muscle on the initial and follow-up examinations several years later. Results: Altogether, 111 UNE patients (114 arms) were studied. During median follow-up period of 880 days (range: 385-1545 days), CMAP amplitude increased (p = 0.02), and conduction block in the elbow segment recovered (from median 17% to 7%; p < 0.001). By contrast, SNAP amplitude did not change (p = 0.89). On needle EMG, spontaneous denervation activity diminished (p < 0.001), motor unit potential (MUP) amplitude increased (p < 0.001), and MUP recruitment remained unchanged (p = 0.43). Conclusions: Findings of the present study indicate that nerve function in chronic focal compression/entrapment neuropathies seems to improve mainly due to the resolution of the conduction block and collateral reinnervation. Contribution of nerve regeneration seems to be minor; the majority of axons lost in chronic focal neuropathies probably never recover. Further studies using quantitative methods are needed to validate present findings.

Electrodiagnostic test results in people with a working diagnosis of cubital tunnel syndrome

BackgroundElectrodiagnostic tests (EDx) can determine when symptoms and signs suggestive of idiopathic ulnar neuropathy at the elbow (cubital tunnel syndrome; CubTS) is due to measurable ulnar neuropathy at the elbow (UNE), cervical radiculopathy, or median neuropathy at the carpal tunnel, and when there is no measurable neuropathology associated with the symptoms. The role of EDx in management of CubTS is debated. Questions(1) What is the percentage of patients with CubTS (both including and excluding patients with a previous electrodiagnosis of idiopathic UNE) that have EDx results consistent with idiopathic UNE, other neuropathology, and no detectable neuropathology (2) What factors (e.g. age and gender); are independently associated with electrodiagnosis of UNE. MethodsWe retrospectively reviewed all medical records of 133 patients with a working diagnosis of CubTS sent for EDx over a 5-year period in one large urban medical center. We recorded data on patient demographics, comorbidities, non-specialist or specialist referring physician, and EDx results. ResultsAmong 133 patients, 61% (N = 81) of EDx identified idiopathic UNE, 14% (N = 18) identified other neuropathology, and for 26% (N = 34) there was no measurable neuropathology. Among the 14 patients with a previous ipsilateral or contralateral electrodiagnosis of UNE, all 14 had electrodiagnosis of UNE. Older age and men were independently associated with an increased likelihood of UNE. ConclusionsThe observation that people diagnosed with CubTS often do not have UNE, particularly if they are relatively young, suggests that the diagnosis of CubTS may benefit from a more stringent clinical prediction rule. Level of EvidenceDiagnostic; Retrospective cohort study; Level III.

Relationship between Clinical Severity and Cross-sectional Area of Ultrasonographic Examinations in Ulnar Neuropathy at the Elbow.

This study explored the relationship between clinical severity of ulnar neuropathy at the elbow (UNE) and ulnar nerve cross-sectional area (CSA) by ultrasound examination to identify appropriate measurement sites for UNE diagnosis and evaluation. In this retrospective analysis, we examined the arms of 37 patients diagnosed with UNE and those of 34 individuals as controls. The ulnar nerve CSAs were measured at 2 cm distal to the tip of the medial epicondyle (dME), the tip of the medial epicondyle (ME), 2 cm proximal to the tip of the medial epicondyle (pME), and any site showing the maximum CSA between the dME and pME (largest dpME). The modified McGowan classification (grades I, IIA, IIB, and III) was used to rate the clinical severity of UNE. For all sites, the CSAs were significantly correlated with clinical severity. The sites showing the maximum CSA were inconsistent between controls and grade IIA patients. Grade IIB patients showed the largest CSA at the ME in the majority of patients. In grade III patients, maximum CSA occurred only at the ME. Serial assessment to detect nerve enlargement at multiple sites was beneficial for mild UNE patients with weakness of the ulnar distal muscles with Medical Research Council (MRC) score of 4 or higher (grade IIA). For severe UNE patients with weakness of the ulnar distal muscles classified as MRC3 or less (grades IIB, III), the most efficient method for detecting enlarged nerves was to initially measure the CSA at the ME.

Mixed Nerve Conduction Study in the Diagnosis of Ulnar Neuropathy at the Elbow

Purpose: This study aims to investigate the ulnar-median mixed nerve latency difference (U-MLD) recorded from the medial aspect of the arm both in patients with ulnar neuropathy at the elbow (UNE) and in healthy individuals and thus to assist in the diagnosis of UNE. Materials and Methods: Twenty-nine patients meeting electrophysiological criteria defined by the American Association of Neuromuscular and Electrodiagnostic Medicine for diagnosis of UNE, and 50 healthy individuals were included in the study retrospectively. All participants' data were evaluated, such as median/ulnar motor and sensory response, U-MLD and the percentage of ulnar mixed nerve response amplitude difference between sides. Results: The U-MLD was significantly higher in patients with UNE than in the control group (1.78 ± 0.64 ms vs. 0.6 ± 0.22 ms, P = 0.000). The percentage of the ulnar mixed nerve response amplitude loss was significantly higher in the patient group compared to the control group (43.9% ± 30.3% vs. 21.4% ± 12.2%, P = 0.018). The U-MLD was significantly higher in the patients with amplitude loss ≥50%, and the ulnar mixed nerve response amplitude loss was ≥50% in all five patients with the ulnar sensory nerve action potential pathology. Conclusions: U-MLD is higher in patients with UNE; it can provide additional data in mild cases regarding the diagnosis of UNE, especially. Furthermore, the criterion that the ulnar mixed nerve response amplitude difference between the sides ≥50% suggests that it can be used to evaluate the severity of UNE.

Vücut Kitle İndeksi ve Mononöropatiler Arasındaki İlişki

Aim: The study aimed to find out whether there is a relationship between the mononeuropathies of the median, ulnar, radial, peroneal, and sciatic nerves and body mass index (BMI). Material and Methods: Patients whose clinical and electrodiagnostic findings were compatible with carpal tunnel syndrome (CTS), ulnar neuropathy at the elbow (UNE), radial neuropathy at the spiral groove (RNS), peroneal neuropathy at the fibular head (PNFH), and sciatic injury due to intramuscular injection (SNIII) were included in this retrospective cohort study. In addition, controls whose clinical and electrodiagnostic features were not compatible with mononeuropathy were included in the study. The BMI values of all participants were analyzed. Results: One hundred thirty-one CTS patients, 53 UNE patients, 6 RNS patients, 25 PNFH patients, 72 SNIII patients, and 53 controls were included in the study. The BMI of CTS patients was higher than the BMI of controls (p&amp;lt;0.001), PNFH patients (p&amp;lt;0.001), and SNIII patients (p&amp;lt;0.001). The BMI of SNIII patients was lower than the BMI of controls (p&amp;lt;0.001), CTS patients (p&amp;lt;0.001), and UNE patients (p&amp;lt;0.001). The BMI of PNFH patients was lower than that of CTS patients (p&amp;lt;0.001) and UNE patients (p=0.004). No significant correlation was found between BMI values and electrodiagnostic classification of mononeuropathies in the groups. Conclusion: This study showed that high BMI is a risk factor for CTS and low BMI is a risk factor for SNIII. There may also be a relationship between BMI and PNFH, but this should be confirmed by further studies.

Influence of ergonomic factors on peripheral neuropathy under HAV exposure.

Hand-arm vibration (HAV) is a risk factor for carpal tunnel syndrome (CTS) and ulnar neuropathy at the elbow (UNE). It is unclear how ergonomic factors influence the relationship between HAV exposure and CTS and UNE. We aimed to assess the relationship between cumulative HAV exposure and CTS and UNE in workers exposed to HAV from two tools with different ergonomic profiles. We performed nerve conduction studies (NCSs) of the sensory and motor median and ulnar nerves and recorded symptoms indicating CTS and UNE in workers exposed to HAV from impact wrenches or from rock drills. Exposure was measured as cumulative lifetime exposure. We used linear regression adjusted for age and body mass index to assess linear relationships. Sixty-five workers participated (33 rock drill and 32 impact wrench operators). We found inverse linear associations between cumulative HAV exposure and median nerve sensory conduction velocity in impact wrench operators and ulnar nerve motor conduction velocity in rock drill operators (beta of 0.63 and 0.75). Based on NCS findings and symptoms, seven impact wrench operators had CTS and one UNE, and four rock drill operators had CTS and six UNE. Our findings indicate that ergonomic factors influence the development of CTS and UNE under HAV exposure. The ergonomic profile seems to influence which type of neuropathy workers exposed to HAV will develop. Design of occupational exposure guidelines and future studies should be based on ergonomic profile and exposure characteristics for different tools and not merely HAV.

Sympathetic Skin Response in Ulnar Neuropathy at the Elbow.

The sympathetic skin response (SSR) reflects the function of sudomotor sympathetic unmyelinated fibers. This study evaluates SSR abnormalities in ulnar neuropathy at the elbow (UNE). Sympathetic skin response was obtained after electrical stimulation of the glabella recording simultaneously from the hand palm (P), third digit (M3) and fifth digit ipsilateral (U5) and contralateral (cU5) to the side of UNE. Ten consecutive SSRs were recorded from each recording side of all participants. The authors enrolled 31 patients (mean age 54.3 ± 11.4 years) and 25 subjects of a control group (mean age 52.6 ± 11.3 years). The mean of the areas and the area of the largest response of U5-SSR were significantly lower in the patients (106.9 ± 68.9 and 127.8 ± 79.7 μV/s, respectively) than in control group (161.8 ± 116.6 and 197.2 ± 143.3 μV/s, respectively) and in the affected than in the unaffected sides of the patients (155.3 ± 84.8 and 197.7 ± 103.3 μV/s, respectively); there were no differences in U5-SSR latencies and P-SSR and M3-SSR parameters. U5-SSR mean areas and U5-SSR largest area were reduced in 29% and 26% of patients, respectively. The differences between patients and control group and the number of patients with U5-SSR abnormalities increased when the ratios of M3/U5-SSR and U5/cU5-SSR areas were considered. U5-SSR area was related to UNE clinical severity and to some parameters of the ulnar nerve conduction velocity and cutaneous silent period. Sympathetic skin response is useful to demonstrate abnormalities of sympathetic fibers even if UNE patients do not complain for sympathetic symptoms. The SSR abnormalities were evident only if electrophysiological damage of myelinated fibers was moderate or severe.

The Relationship Between Magnetic Resonance Imaging and Electrodiagnostic Studies in Patients with Ulnar Neuropathy at the Elbow

Objective: This study investigated the correlations between magnetic resonance imaging (MRI) and nerve conduction studies (NCS) in patients with ulnar neuropathy at the elbow (UNE).Methods:In total, 46 patients who underwent elbow MRI and NCS at a single center from 2014 to 2018 were included. Motor studies, including segmental and inching tests, and sensory NCS were performed. The 5-point severity score was evaluated based on the signal change and swelling in the fat-suppressed T2 weighted sequence. The findings of MRI and NCS were grouped into 3 categories. The Spearman rank test was used to evaluate correlations between the severity score on MRI and electrodiagnostic parameters.Results:The locations of the lesions on MRI and NCS were correlated in 20 of the 46 patients with UNE, while the other 20 patients had no correlations. Six patients who could not be categorized according to the location showed various findings. The severity score based on MRI showed significant negative correlations with amplitude on the segmental study (r = -0.423, p = 0.002) and the inching study (r = -0.456, p = 0.002), and with conduction velocity in the segmental study (r = -0.526, p &lt; 0.001) and the inching study (r = -0.548, p &lt; 0.001).Conclusion Electrodiagnostic outcomes had negative correlations with the severity score, reflecting the structural changes seen on MRI. Combining electrodiagnostic studies and MRI could make the diagnosis and localization more precise.

Conservative therapy in ulnar neuropathy at the elbow (Review).

Ulnar neuropathy at the elbow (UNE) is the second most frequent entrapment syndrome in the upper limb after carpal tunnel syndrome. Clinical features are validated through electromyographic and sonographic examination. Although the two aforementioned entrapment syndromes share common pathophysiological traits, the conservative treatment approach for mild and moderate cases of UNE differs from that for median nerve entrapment. The present study identified 23 different types of scientific articles aimed to address this issue. The research stressed the importance of patient education and activity modification. Night splinting offers clinical and functional improvement. Although corticosteroid injections play a role in selected cases, their utility remains to be validated. Physiotherapy trials evaluated ultrasound, low-level laser therapy, diathermy, extracorporeal shock wave therapy and dry cupping. Neurodynamic mobilization may add value to therapeutic approaches and should be a part of it.

Ultrasonographic Evaluation of Ulnar Neuropathy Around the Elbow in Diabetes Mellitus

Objective: We evaluated the usefulness of ultrasonography for subclinical ulnar neuropathy at the elbow (UNE) in patients with diabetes.Methods: Ultrasonography of the ulnar nerve was performed on 140 limbs in 73 patients with diabetes mellitus at 8 standardized sites proximal and distal to the medial epicondyle (1-cm intervals). The ulnar nerve cross-sectional area (CSA) at each site was analysed according to the presence of electrophysiological diabetic polyneuropathy (DPN) or UNE (UNE_e).Results: Fifty-nine limbs were electrophysiologically normal, 22 limbs had UNE, 39 limbs had DPN, and 20 limbs had DPN and UNE_e. In patients without DPN, the maximal CSA, swelling ratio, and CSAs were greater in the UNE_e group than in the normal group (p &lt; 0.01). No significant differences were noted between the DPN and DPN+UNE_e groups regarding the CSAs, maximal CSA, and swelling ratio.Conclusion: Ultrasonography of ulnar nerve swelling is helpful for diagnosing subclinical UNE in patients with diabetes.

Diagnosing ulnar neuropathy at the elbow on MRI: importance of the longitudinal extent of the hyperintense ulnar nerve.

To evaluate the usefulness of the longitudinal extent (LE) of high ulnar nerve signal intensity (SI) for the diagnosis of ulnar neuropathy at the elbow (UNE). This retrospective study included 68 patients who underwent elbow MRI. Twenty-seven and 41 patients were enrolled in the UNE and control groups, respectively. Qualitative and quantitative analyses of the SI and size of the ulnar nerve at the cubital tunnel, proximal, and distal to the cubital tunnel were performed. Cross-sectional area (CSA) and nerve-to-muscle contrast ratio (NMCR) were measured at each level. The LE of the hyperintense ulnar nerve was evaluated using axial and coronal images. The presence of space-occupying lesions (SOLs), subluxation, and muscle denervation were recorded. Univariate and multivariate analyses were performed to identify independent predictive factors. Ulnar nerve hyperintensity at and distal to the cubital tunnel, presence of compression, SOL, muscle denervation, LE of hyperintense ulnar nerve, NMCR, and CSA at and distal to the cubital tunnel significantly differed between the two groups. Multivariate logistic regression analysis showed that the LE of the hyperintense ulnar nerve and CSA at the cubital tunnel were independent predictive factors for UNE (p < 0.05). LE of the hyperintense ulnar nerve could be a useful predictive factor for UNE.

Radiographs and Corticosteroid Injections at a New Patient Visit for Care of Carpal Tunnel Syndrome and Ulnar Neuropathy at the Elbow

Introduction The benefit of radiographs or steroid injection for idiopathic carpal tunnel syndrome (CTS) or ulnar neuropathy at the elbow (UNE) is open to debate. We assessed: (1) Radiographs ordered and injections performed at a new patient visit for patients presenting with either idiopathic CTS or UNE; (2) The estimated payment reduction if we omit these interventions; and (3) Patient age, sex, geographic region, and work status associated with radiographs or injections at a new patient visit for patients presenting with either idiopathic CTS or UNE.Materials and Methods Using a large database of commercial insurance claims, we identified patients with a new visit for either CTS (N = 9,522), UNE (N = 2,507), or both (N = 962; 8.7%). We identified injections and radiographs, and estimated total payments for these interventions. We created three multivariable logistic regression models for each diagnosis to identify factors associated with the interventions.Results Nearly one third of patients had radiographs at a new patient visit (30% and 32% for idiopathic CTS and UNE, respectively). Nearly 10% of patients with CTS and 2.6% with UNE received an injection. Both radiographs and injections representing annual minimum payments of over $345,000 and $294,000, respectively. Among people with CTS, radiographs were independently more common in the South and less common in the West. Injection for CTS was associated with younger age; North, Central, and South regions; and retired employment status. For people with UNE, radiographs were independently associated with younger age; South or West region; and retired or working employment status. Injection for UNE was associated with retired employment status.Conclusion The prevalence of radiographs and injections suggests opportunities for savings, which might benefit clinicians with bundled or capitated payments and patients with large copayments or deductibles. The observed variation may reflect debate about whether these interventions are worthwhile.Level of Evidence Diagnostic; Retrospective Database Level III study.

Diagnosis and Severity Evaluation of Ulnar Neuropathy at the Elbow by Ultrasonography: A Case-Control Study.

Traditional diagnostic techniques such as clinical examination and electrodiagnosis are less sensitive in diagnosing ulnar neuropathy at the elbow (UNE). Ultrasonography (USG) is increasingly being used to diagnose UNE. However, clinical applicability is limited by the lack of uniformity in the previous studies. Therefore, we aimed to study in the Indian patients the diagnostic utility of the ulnar nerve cross-sectional area (CSA) and a novel parameter-entrapment index (EI) in UNE measured by USG and to find if both these parameters correlate with the electrodiagnostic severity. This retrospective casecontrol study included 28 patients (36 nerves) of UNE and 12 (24 nerves) age- and gender-matched healthy controls. Electrodiagnostic severity was graded using the Padua classification. USG was performed in both groups, and CSA was measured at the medial epicondyle (ME) and 5 cm proximally and distally. EI was calculated by multiplying the ratio of CSA above ME over CSA at ME by 100. Best cutoffs were derived by the receiver operating characteristic curve analysis. UNE group had significantly higher CSA at all three locations and lower EI than the control group. CSA at ME ≥9.7 mm2 and EI ≤61.5 has sensitivity and specificity of 88.9%/87.5% and 72.2%/79.2%, respectively. There was no significant difference in CSA and EI between nonsevere and severe UNE groups. CSA at ME and EI have good sensitivity and specificity in diagnosing UNE. However, they cannot differentiate nonsevere from severe UNE.

Evidence-based guideline: Neuromuscular ultrasound for the diagnosis of ulnar neuropathy at the elbow.

The purpose of this literature review is to develop an evidence-based guideline for the use of neuromuscular ultrasound in the diagnosis of ulnar neuropathy at the elbow (UNE). The proposed research question was: "In patients with suspected UNE, does ulnar nerve enlargement as measured with ultrasound accurately identify those patients with UNE?" A systematic review and meta-analysis was performed, and studies were classified according to American Academy of Neurology criteria for rating articles for diagnostic accuracy. Based on Class I evidence in four studies, it is probable that neuromuscular ultrasound measurement of the ulnar nerve at the elbow, either of diameter or cross-sectional area (CSA), is accurate for the diagnosis of UNE. For patients with symptoms and signs suggestive of ulnar neuropathy, clinicians should offer ultrasonographic measurement of ulnar nerve cross-sectional area or diameter to confirm the diagnosis and localize the site of compression (Level B).

Cutaneous silent period in ulnar neuropathy at the elbow.

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. 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. We enrolled 37 UNE patients (mean age 55.4 ± 11.2y) and 30 controls (mean age 51.2 ± 11.1y). 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 ± 8ms, respectively) than in controls (78.2 ± 8.1 and 79.4 ± 7.6ms, respectively). The D5-FDI duration of CSP was shorter in patients (52.2 ± 8.3ms) than in controls (55.8 ± 7ms). 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. 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.