Laterality and risk factors for ulnar neuropathy at the elbow.

BACKGROUND: Ulnar neuropathy at the elbow (UNE) is the second commonest entrapment neuropathy after carpal tunnel syndrome (CTS) and yet the laterality is not well delineated. Our aim was to establish the laterality of UNE in a large cohort of patients. METHODS: All new patients with clinical and electrodiagnostic (EDX) confirmed UNE over a 13-year period were included. We used multivariate analysis to examine potential predictors of laterality, and unilateral vs bilateral UNE. RESULTS: Of 880 cases, 61% were left-sided and 39% right-sided. These proportions did not change regardless of the handedness of the patient. Patients with bilateral UNE were much more likely to be older male and have a variety of comorbidities. CONCLUSIONS: UNE appears to be present on the left 50% more often than on the right, regardless of the patient's handedness.

The external elbow measure as surrogate of the anatomical width of cubital groove and possible risk factor of ulnar neuropathy at the elbow.

Introduction: There are no studies on elbow anthropometry in ulnar neuropathy at the elbow (UNE). We aimed to test the interrater agreement of external elbow measurements with caliper, the matching of external width of cubital groove (WCG) measures with those obtained through conventional radiography (XR) and ultrasonography (US). The final aim was to evaluate the differences of anthropometric elbow and body measures between UNE cases and controls with multicenter prospective study.Materials and methods: After common training of five observers for external elbow and body anthropometric measurements, we assessed the interrater agreement of measures in a single blind measurement session in 16 healthy volunteers. Then we verified if external WCG measures in eight and four of the above 16 subjects matched with those obtained with US and XR. Finally, we enrolled 40 consecutive idiopathic UNE cases in four electromyographic labs matched for sex and age with 40 controls to evaluate the differences of anthropometric measures.Results: There was high interrater agreement of all anthropometric body and elbow measures (Kendal's and interclass correlation coefficients between 0.84 and >0.9). We found high relations between WCG caliper measures and those obtained with US and XR (r > 0.9). WCG was smaller in cases than in controls (13.2 vs.15.7 mm, p < 0.001). There were no differences in body anthropometric measures (BMI and waist-to-hip ratio).Conclusion: The external measurement of WCG is reliable and reproducible and may be risk factor of UNE. Future studies should be performed in lager samples evaluating the relations with lifestyle and occupational factors.

Ulnar neuropathy at wrist: entrapment at a very "congested" site.

Ulnar tunnel syndrome indicates ulnar neuropathy at different sites within the wrist. Several classifications of ulnar tunnel syndrome are present in literature, based upon typical nerve anatomy. However, anatomical variations are not uncommon and can complicate assessment. The etiology is also complex, due to the numerous potential causes of entrapment. Clinical examination, neurophysiological testing, and imaging are all used to support the diagnosis. At present, many therapeutic approaches are available, ranging from observation to surgical management. Although ulnar neuropathy at the wrist has undergone extensive prior study, unresolved questions on diagnosis and treatment remain. In the current paper, we review relevant literature and present the current knowledge on ulnar tunnel syndrome.

Bilateral position-related ulnar neuropathy at elbow in pediatric population and review of the literature.

Perioperative ulnar neuropathies attributed to inappropriate arm positioning and padding during surgical procedures are commonly found in adults. However, their extremely rare incidence in the pediatric population may cause absent awareness of the risk of nerve injury in anesthetized pediatric patients. Furthermore, young patients respond to conservative treatment of neuropathy less favorably than adults and their response also depends on the pathomechanism of the ulnar nerve injury. A surgeon's or anesthetist's failure to recognize all of these specifics in children may result in substantial morbidity of young patients leading to lawsuits. Fortunately, with an adequate knowledge of surgical anatomy and types of procedures and positions in which the ulnar nerve is particularly vulnerable, and familiarity with measures to minimize the potential for neuropathy, this serious complication can be prevented. The aims of this review are to highlight personal experience and current knowledge of the rare position-related ulnar neuropathy, both from a clinical and anatomical-pathophysiological perspective, and to raise awareness about this rare but serious complication in the pediatric population.

High resolution sonographic examination: a newer technique to study ulnar nerve neuropathy in leprosy.

Objectives: A prospective case control study was conducted to calculate normal dimensions of ulnar nerve and study the size, echotexture and morphologic alterations in ulnar nerve in patients with leprosy. Methods: The study group included 48 patients diagnosed with leprosy on basis of clinical, bacteriologic and/or histopathologic evaluation. Sonographic measurements were taken at 3 levels around elbow. The morphology and vascularity were also studied. Control group consisted of 60 clinically normal ulnar nerves, on which ultrasound was performed to calculate normal parameters. 96 Ulnar nerves were independently evaluated clinically and on ultrasound. The mean cross sectional area and diameters (both antero-posterior and mediolateral) of controls at all three levels were calculated. The normal sonographic dimensions of ulnar nerve were calculated based on Mean ± 2SE and beyond the upper limit of normal was considered enlarged on ultrasound. Statistical analysis was done using SSPS version 17.0. Results: The dimensions of ulnar nerve were significantly larger in leprosy group for all levels (P value , 0.001). Sonographic abnormalities included hypoechoic areas (61·45%), loss of fascicular pattern (same 61·45%) and focal hyperechoic areas (48·95%). 37·5% of nerves (6 out of 16) with clinical evidence of reaction showed endoneural vascularity. Conclusions: We conclude that by detecting enlargement and/or morphologic alterations of ulnar nerve, sonography can objectively determine involvement of ulnar neuropathy in leprosy.

Primary Neuritic Hansen's Disease presenting as Ulnar Nerve Abscess in a Human Immunodeficiency Virus Positive Patient.

Leprosy has been increasingly known to have an enigmatic relationship with human immunodeficiency virus infection. Co-infection may result in atypical manifestations of leprosy. A 45-year old human immunodeficiency virus-positive male; agricultural laborer presented with a swelling over right elbow, right hand deformity, generalized itching and recurrent vesicles overthe perinasal area. Clinical and investigational findings were consistent with mononeuritic type of Hansen's disease with right sided silent ulnar nerve abscess, partial claw hand. CD4+ count of the patientwas 430 cells/cmm. This patient also hadherpes simplex labialis, with HIV-associated pruritus. To the best of our knowledge such an atypical presentation has not been reported earlier.

Magnetic resonance imaging findings in acute elbow dislocation: insight into mechanism.

PURPOSE: To identify with magnetic resonance imaging the location and severity of ligamentous injury after acute elbow dislocations. Based on observations that many elbow dislocations arise from an initial acute valgus load, we hypothesized that all patients would have a high-grade medial injury but not all would demonstrate injury of the lateral ligaments. METHODS: The medial collateral ligament was subdivided into anterior bands of the anterior bundle of the medial collateral ligament (MCL) and posterior bands of the anterior bundle of the MCL, whereas the lateral collateral ligament was divided into the lateral ulnar collateral ligament and the radial collateral ligament. Distinction on magnetic resonance imaging was made between normal morphology and low-grade partial tear (< 50% of the ligament fibers), high-grade partial tear (≥ 50%), and full-thickness disruption. The site of disruption was also characterized. RESULTS: Acute magnetic resonance imaging studies for 16 patients were included. No low-grade tears or intact evaluations of either the anterior or posterior bands of the anterior bundle of the MCL were observed; most demonstrated complete tears. The lateral ulnar collateral ligament most frequently showed complete disruption but was occasionally intact. The radial collateral ligament infrequently showed full disruption. Complete tears involving either the anterior or posterior portions of the anterior band of the MCL were significantly more common than complete tears involving the ligaments on the lateral side. CONCLUSIONS: After elbow dislocation, complete ligamentous tears were more common on the medial versus the lateral side. Whereas the lateral ligaments were occasionally preserved, this was never observed on the medial side. These data suggest a sequence of failure starting on the medial side with subsequent variable energy dissipation laterally. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic IV.

Extensive ulnar nerve necrosis: a complication of tuberculoid leprosy.

Pure neural leprosy without cutaneous manifestations is a relatively rare manifestation of leprosy. It can present as a mono- or poly-neuritis with sensory and/or motor impairment. Neural leprosy may or may not be associated with thickening of the involved nerve. We report the case of a 14 year old boy with extensive ulnar nerve necrosis who was diagnosed to have tuberculoid leprosy. What makes this case unique is that we have here a case of pure neural leprosy with a single nerve turned 'necrotic'.

The pattern of muscle involvement in ulnar neuropathy at the elbow.

OBJECTIVE: To determine the pattern of muscle involvement in patients with ulnar neuropathy at the elbow. MATERIALS AND METHODS: This study evaluated all patients referred for upper limb electrodiagnostic study (EDX) during 2007-2011 and included. patients with clinical signs and symptoms of ulnar neuropathy at the elbow. All patients had nerve conduction studies (NCS) for ulnar neuropathy. Needle electromyography (EMG) of four ulnar innervated muscles, flexor carpi ulnaris (FCU), flexor digitrom profoundus (FDP), first dorsal interosseous (FDI) and abductor digiti minimi (ADM)) was evaluated. RESULTS: During the study period 34 (23 males and 11 females) patients were diagnosed with ulnar neuropathy at the elbow and three of them had bilateral involvement. Muscle involvement by EMG was as follows: FDI: 91.9%, ADM: 91.3%, FCU: 64.9% and FDP: 56.8%. CONCLUSION: In this study, EMG abnormalities of nerve damage were presented more commonly in the FCU muscle than in the FDP in patients with ulnar nerve lesion at the elbow.

Ulnar neuropathy at the elbow: MR neurography--nerve T2 signal increase and caliber.

PURPOSE: To assess nerve T2 signal and caliber as diagnostic signs at magnetic resonance (MR) neurography in ulnar neuropathy at the elbow (UNE). MATERIALS AND METHODS: This prospective study was approved by the institutional review board, and written informed consent was obtained from all participants. Twenty patients with UNE were graded by using clinical criteria and nerve conduction studies as mild (n = 12) and severe (n = 8) and were compared with 20 healthy control subjects. All subjects underwent ulnar nerve MR neurography (in-plane resolution of 0.4 × 0.4 mm) covering the elbow region, including T2-weighted imaging with fat suppression (turbo inversion-recovery magnitude sequence: repetition time msec/echo time msec/inversion time msec, 6, 120/66/180) and T1-weighted turbo spin-echo imaging (843/16). Nerve T2 signal increase, measured by using T2-weighted contrast-to-noise ratios across the cubital tunnel, and nerve caliber, determined by using T1-weighted pixelwise measurement of cross-sectional nerve area, were evaluated as diagnostic signs. Qualitative assessment by using visual grading was performed additionally. RESULTS: Diagnostic performance, as determined with area under the receiver operating characteristic curve (AUC), was excellent for nerve T2 signal to discriminate UNE from a normal finding (AUC = 0.94; 95% confidence interval [CI]: 0.87, 1.00) and was excellent for nerve caliber to discriminate severe from mild UNE (AUC = 0.95; 95% CI: 0.85, 1.00). Qualitative assessment demonstrated sensitivity of 83% and specificity of 85% for MR neurography of UNE. CONCLUSION: Nerve T2 signal increase seems to be an accurate sign to determine the presence of UNE. Nerve caliber enlargement discriminates severe from mild UNE. UNE may be diagnosed with high accuracy by means of quantitative or qualitative evaluation of these signs.

Ultrasonography in ulnar neuropathy at the elbow: a critical review.

INTRODUCTION: Ultrasonography of the ulnar nerve has been recommended as a useful additional test in ulnar neuropathy at the elbow (UNE). METHODS: We searched the literature and systemically reviewed all clinical trials in UNE. We also looked for articles about the normal sonoanatomy and specific causes of UNE. RESULTS: Seven of 14 clinical trials in UNE were suitable for further analysis. Ultrasonographic ulnar nerve size measurement appears to be a test with good diagnostic accuracy. The most frequently reported abnormality was an increased cross-sectional area of the ulnar nerve at the elbow. However, several studies had methodological flaws. In addition, the ultrasonographic techniques and study designs differed among the studies. There were a few other uncontrolled studies about the underlying causes of UNE. DISCUSSION: The role of ultrasonography in UNE seems promising but could not be firmly established. More prospective studies are needed, and we make several recommendations for further research.

An unusual location of ulnar nerve pathology: a perineurioma of the ulnar nerve in the upper arm.

A young man presented with progressive motor weakness and atrophy of the ulnar muscles of his left hand over a period of more than 2 years. Electrodiagnostic studies indicated an ulnar nerve lesion, but it was not localized. High-resolution sonography of the ulnar nerve revealed an enlarged and hypoechogenic ulnar nerve at an unusual location, namely 12.5 cm proximal to the medial epicondyle. Histology showed that this was an intraneural perineurioma. High-resolution sonography of the ulnar nerve is very useful in the discovery of this unusual location of nerve pathology and may assist in its early detection.

Temporoparietal fascial free flap for correction of first web space atrophy.

Fourteen temporoparietal fascial free flaps were used for correction of first web space atrophy from ulnar nerve palsy in 13 patients. Ten sustained ulnar nerve injuries and three suffered from leprosy. The procedures were performed under general anesthesia except one leprosy patient with bilateral ulnar nerve palsy in which local anesthesia and brachial block were employed to harvest bilateral free flaps and recipient site preparations, respectively. The follow-up time varied from 4 to 64 months. The postoperative results were satisfactory and there was no resorption of the free flaps. The consistency of the augmented first web space was soft and compressible like natural feel. The size of the flap was more than enough for augmentation of first web space and donor site morbidity was minimal and accepted by all patients. We conclude that temporoparietal fascial free flap is an ideal autogenous tissue for correction of first web space atrophy.

Anomalies of the flexor carpi ulnaris: clinical case report and cadaveric study.

Flexor carpi ulnaris (FCU) is an ever-present muscle of the anterior flexor compartment of the forearm. Variations of FCU are uncommon, with additional slips or heads of muscles described, and only one reported case of an accessory muscle. We describe a unique clinical case report in which an accessory FCU was identified and describe the findings of 5,000 cadaveric dissections of the forearm, performed as part of an ongoing institutional study of anatomical variations. An aberrant accessory forearm flexor muscle was identified incidentally at the wrist during surgery for an anterior interosseous to ulnar nerve transfer for management of ulnar nerve palsy. This muscle was seen running superficial to the ulnar nerve and radial to the FCU proper, arising from the common flexor origin and inserting at the triquetral carpal bone. This was therefore suitably acknowledged as an "accessory FCU". The anomaly was identified as bilateral using ultrasound imaging, and was found to be anomalously innervated by the median nerve with nerve conduction studies. A subsequent review of 5,000 cadaveric dissections of the forearm did not identify any such variations related to FCU, despite identifying a range of variations of the other forearm flexor musculature. While the scarcity of this anomaly is thus highlighted, consideration of an accessory FCU, and its aberrant innervation is important in a range of surgical approaches.

Patient with amyloidoma of the ulnar nerve and salivary glands.

Amyloidomas of the peripheral nervous system have been reported rarely. We describe a patient with a history of localized amyloidosis of the salivary glands who presented a few years later with paresthesias of her left medial arm, forearm, and fifth digit. A mass affecting the left ulnar nerve was confirmed by MRI studies. It was excised and proven on pathological examination to be an amyloidoma. The benign course of this patient's illness is consistent with localized amyloidosis affecting two different organs.

MRI imaging of ulnar leprosy abscess.

Leprosy is a chronic granulomatous infection, caused by mycobacterium leprae, primarily affecting the peripheral nerve trunks and cutaneous nerves. It classically presents with neural or dermal signs and symptoms. The indolent course of leprosy may manifest as erythema nodosum (appearance of tender inflamed subcutaneous nodule) and reversal reaction (inflammation in the previous skin lesion, appearance of new skin lesions, neuritis and abscess). Ulnar nerve is most commonly involved. This report illustrates the MR imaging appearance of ulnar nerve abscess.