RT Journal Article SR Electronic T1 Electrodiagnosis of ulnar nerve entrapment at the elbow JF Neurosciences Journal JO Neurosciences (Riyadh) FD Prince Sultan Military Medical City SP 249 OP 253 VO 14 IS 3 A1 Yuksel, Gulbun A1 Karlikaya, Geysu A1 Tutkavul, Kemal A1 Akpinar, Ayse A1 Orken, Cihat A1 Tireli, Hulya YR 2009 UL http://nsj.org.sa/content/14/3/249.abstract AB OBJECTIVE: To evaluate the different localizing electrodiagnostic techniques of ulnar nerve entrapment at the elbow (UNE), particularly, comparison of the sensitivities of long segment stimulation across the elbow, versus short segment stimulation.METHODS: Patients who were referred to the Neurophysiology Laboratory of Haydarpasa Numune Training and Research Hospital, Istanbul, Turkey between 2000-2004 with a preliminary diagnosis of UNE were retrospectively evaluated. We compared the sensitivity of studying long segments (8-12 cm) versus short segments (3 cm) for the diagnosis of UNE in 93 limbs.RESULTS: The study group consisted of 55 females and 31 males. Slowing of the conduction velocity (<50 m/sn) across the elbow was recorded in 48.4% of the limbs with long segment studies, and 73% of the limbs with short segment studies. In 82% of cases, an amplitude drop of the compound muscle action potential (CMAP) was also recorded. A CMAP amplitude drop of 10-30% between the wrist and elbow was recorded in 35 limbs (37.6%), while a drop of more than 50% was only recorded in 5 limbs (5.4%).CONCLUSION: Short segment studies are sensitive for the electrodiagnosis of UNE, and although a CMAP amplitude drop is recorded in most patients, an amplitude drop consistent with a conduction block (>50%) is rare.