Correlation between Severity of Diabetic Neuropathy and Somatosensory Evoked Potentials Study

OBJECTIVE: To investigate the clinical applicability of the somatosensory evoked potentials (SEPs) study in early detection of diabetic neuropathy, and compare the results in different degrees of the disease. METHOD: The study was performed retrospectively with prospective data collection. The Toronto clinical scoring system was taken as well as nerve conduction study, needle electromyography, and SEPs study with median and posterior tibial nerve stimulations in thirty-eight diabetic patients and twenty non-diabetic adults. The subjects were divided into the non-neuropathy group and the neuropathy group, and the latter was divided into three subgroups (suspected, probable, and definite) according to the degree of neuropathy. Statistical analysis was performed with height and age-related correction of reference values of the latency of SEPs with posterior tibial nerve stimulation. RESULTS: The Toronto clinical scoring system showed concordance with the degree of the diabetic neuropathy (p<0.05, correlation coefficient=0.827). SEPs study with posterior tibial nerve stimulations showed statistically significant latency delay, not only in the neuropathy group, but also in the non-neuropathy group, compared with the non-diabetic group (p<0.05). Moreover, the latency delay was noted in proportion to the degree of the diabetic neuropathy within the neuropathy group. Interpretation of the data with height and age-corrected reference values of latency of posterior tibial SEPs had stronger correlation. CONCLUSION: The SEPs study is useful in the early diagnosis of diabetic neuropathy. However, application of the SEPs to clinical use needs to go through height and age correction.

Intramuscular Hemangioma Mimicking Myofascial Pain Syndrome: A Case Report

Intramuscular hemangioma, an infrequent but important cause of musculoskeletal pain, is often difficult to establish the diagnosis clinically. This report describes a case of a 32-yr-old woman who presented with severe left calf pain for 10 yr. Initial conservative treatments consisting of intramuscular electrical stimulation, herb medication, acupuncture, and intramuscular lidocaine injection under the diagnosis of myofascial pain syndrome in other facilities, failed to alleviate the symptoms. On physical examination, there was no motor weakness or sensory change. Conventional radiography of the leg revealed a soft tissue phlebolith. Conventional angiography study showed hemangioma. Intramuscular hemangioma within the soleus muscle was confirmed by magnetic resonance imaging. Following surgical excision of the hemangioma, the patient's symptom resolved completely. Intramuscular hemangioma is a rare cause of calf pain and should be considered in the differential diagnosis if a patient with muscle pain, particularly if associated with a soft tissue mass, fails to respond to conservative treatment.

Abductor Digiti Minimi and First Dorsal Interosseous Recordings for the Localization of Ulnar Neuropathy at the Elbow

OBJECTIVE: To compare abductor digiti minimi (ADM) recording with first dorsal interosseous (FDI) recording for the localization of ulnar neuropathy at the elbow. METHOD: The subjects were consisted of 28 patients of ulnar neuropathy at the elbow. The subjects were divided into 3 groups: focal demyelination; focal demyelination and axonal degeneration; axonal degeneration. Compound muscle action potentials were recorded from both ADM and FDI muscles and ulnar nerve was stimulated at the wrist, 2 cm distal and 8 cm proximal to the medial epicondyle. Focal demyelination were analyzed into conduction block and/or conduction slowing. RESULTS: Conduction block was observed in 13 out of 28 patients (46%) with FDI recording and 11 out of the 28 patients (39%) with ADM recording. Conduction block was found solely with FDI recording in 3 patients, whereas 1 patient showed conduction block with ADM recording only. Concomitant segmental motor conduction slowing was observed in 11 out of 13 patients with FDI recording and in 6 out of 11 patients with ADM recording. CONCLUSION: Measurements to the FDI had a higher yield of abnormality than the ADM. In some patients, only one recording muscle showed abnormal findings. Therefore, it may be useful to record from both muscles to localize ulnar neuropathy at the elbow.

Frequency of Carpal Tunnel Syndrome acoording to the Severity of Diabetic Neuropathy

OBJECTIVE: To investigate the frequency of carpal tunnel syndrome (CTS) according to the severity of diabetic polyneuropathy. METHOD: Electrophysiologic study was performed in 456 patients (male 222, female 233, average age 58) with diabetes mellitus. Electrophysiologically diagnosed diabetic neuropathy was classified as suspected, probable or definite. CTS was also diagnosed both in cases with and without underlying diabetic peripheral neuropathy. The ANOVA test was used for statistical analysis. RESULTS: Out of 456 diabetic patients, 228 patients were diagnosed as diabetic peripheral neuropathy. The patients with diabetic neuropathy consisted of 107 cases (23.5%) of sus pected group, 95 cases (20.8%) of probable group and 26 cases (5.7%) of definite group. The frequencies of concomitant CTS were 49 cases (21.5%) in 228 diabetic patients without diabetic polyneuropathy, 31 cases (29%) in suspected group and 30 cases (31.6%) in probable group. These were statistically significant. However, only one case showed concomitant CTS in 26 cases of definite group. CONCLUSION: The frequency of CTS was higher in probable group compared to suspected group. However the frequency decreased in definite group because there is a difficulty in the differential diagnosis of two disease in the cases of advanced peripheral neuropathy.

Dorsal Ulnar Cutaneous Nerve Conduction Study in Entrapment Ulnar Neuropathy at the Elbow

OBJECTIVE: To evaluate the electrophysiologic findings of the dorsal ulnar cutaneous nerve (DUCN) in ulnar neuropathy at the elbow and to correlate the sensory nerve action potential (SNAP) amplitude of DUCN to those of ulnar compound muscle action potential (CMAP) and SNAP. METHOD: The subjects were 39 patients diagnosed as ulnar neuropathy at the elbow. Electrophysiologic classification consisted of 3 groups: conduction block (CB); conduction block and axonal degeneration (CBAD); axonal degeneration (AD). Findings of DUCN conduction study were evaluated according to the electrophysiologic classification. The amplitude of DUCN was correlated to those of CMAP and SNAP. RESULTS: The DUCN conduction study was normal in all cases of CB (4 cases), but was abnormal in 21 cases of CBAD (23 cases) and in 10 cases of AD (12 cases). Even in the cases with AD, 4 cases showed normal DUCN potentials. Correlations of DUCN to ulnar SNAP and CMAP were r=0.48, (p<0.01) and r=0.33, (p<0.05), respectively. CONCLUSION: Findings of DUCN may be related to the fascicular involvement of the ulnar nerve at the elbow. Although it is possible for the DUCN to be spared in ulnar neuropathy at the elbow, electrophysiologic measurement of the DUCN response remains useful, but only in those cases where it is abnormal, which suggests the lesion to be at a more proximal site.