Amyotrophic lateral sclerosis presenting as typical split hand syndrome

Abstract

DESCRIPTIONA 38-year-old man presented to a hospital with weakness of both hands (right>left) with associated generalised weakness for the past 2 years. The patient initially noticed weakness and thinning of his right hand followed by the left for 2 years, then he noticed a thinning of the arms, right more so that left, and his right thigh for the past 6 months. General examination showed flattening over the right shoulder and wasting of the thenar eminence on both hands with normal hypothenar muscles (figures 1 and 2). Nervous system examination showed tongue fasciculations and significant asymmetrical wasting of abductor pollicis brevis (APB), and first dorsal interossei (FDI) with sparing of abductor digiti minimi (ADM) was noted (figures 1 and 2), but strength was normal in all four limbs with the exception of bilateral weak pincer grip. The patient had wasting of both arms (circumference 10 cm above the olecranon process was 18 and 21 cm for the right and left arms, respectively) and right thigh (circumference 10 cm above tibial tuberosity was 35 cm with left side being 40 cm). The patient had exaggerated reflexes in all four limbs with flexor plantar response and fasciculations most noticeably in deltoid, pectoral and quadriceps muscles suggesting definitive diagnosis of amyotrophic lateral sclerosis (ALS) by EL Escorial criteria. Other cranial nerves, motor, sensory and

Dissociated lower limb muscle involvement in amyotrophic lateral sclerosis and its differential diagnosis value

“…They revealed that compound muscle action potentials (CMAP) of APB and FDI were significantly lower than CMAP of ADM. The results were presented as split hand index (SI, ) 5,6 .They found that the “split hand” could be used to differentiate ALS from CSA 5,7 . Recently, Neil reported dissociated lower limb muscle involvement in ALS 8 .…”