[Evaluating the sensitivity of sternocleidomastoid muscle electromyography in differential diagnosis of amyotrophic lateral sclerosis from cervical spondylotic myelopathy]

Differentiation between amyotrophic lateral sclerosis [ALS] and cervical spondylotic myelopathy [CSM] not only for those similar clinical features but also for different handling is very important in clinical practice. Considering that EMG of the sternocleidomastoid muscle [SCM] is using for differential diagnosis of these diseases in Iran, present study was aimed to evaluate the sensitivity of sternocleidomastoid muscle electromyography in differential diagnosis of ALS from CSM. We conducted a retrospective cohort study. Subjects [34patients] were identified from suspected ALS or CSM patients who referred to Loqhman hospital and evaluated with using of the sternocleidomastoid muscle electromyography [SCM-EMG] between March 2006 and February 2008 as part of the diagnostic workup. Clinical characteristics and MRI results were derived from subject's medical records. Follow-up clinical evaluation during two years after initial diagnostic evaluation was available as a gold standard for confirmation the EMG results. We used two way tables for calculating sensitivity. SCM-EMG was abnormal in 10 [29.4%] patients, all of whom were subsequently diagnosed with ALS. The sensitivity of SCM-EMG was 0.71 [95% CI, 0.42 +/- 0.91] for the diagnosis of ALS. Although our findings suggest that SCM-EMG is an extremely useful adjunct for the diagnosis of ALS, but further studies with larger sample size is needed for its application as a useful test "Ruling in" for the diagnosis of ALS

[Evaluating the diagnostic value of somatosensory evoked potentials in the diagnosis of meralgia paraesthetica]

Although the diagnosis of Meralgia paraesthetica [MP] is always made based on clinical background, but electrophysiological evaluation is helpful in confirming the diagnosis. We investigated the Somatosensory Evoked Potentials [SEPs] of the lateral femoral cutaneous nerve [LFCN] of the thigh. Because of lack of knowledge in case of its diagnostic utility in our country, this study is performed. In this cross sectional study, we entered sixty consecutive patients referred to the Loqman Hospital in Tehran [2009-2010], who have clinical symptoms and signs consistent with a diagnosis of MP underwent bilateral studies of SEPs elicited by stimulation of the LFCN of the thigh. SEPs was abnormal in 32 [53.3%] patients, all of whom were clinically diagnosed with MP. The specificity of the SEPs test was 98.3% [95% CI, 91.0% 99.9%] for the diagnosis of MP. Our findings suggest that SEPs is an extremely useful test for ruling out the diagnosis of MP