Abstract

A 64 yr old right-handed mechanic presented with four weeks history of clumsy right hand with ongoing problems at work. He described stiffness and problems with co-ordination. At the time of presentation he was noted to be walking with his right arm behind him and not being aware of this. His initial examination showed Mini Mental Score of 26/30, with ongoing involuntary movements of his right arm (Video).

Video shows spontaneous elevation of right arm with occasional myoclonic jerks. Video also demonstrates patient's difficulty in following simple motor tasks and his comments that his arm “has a mind of its own”.

His MRI head (Figure 1) showed typical cortical ribboning pattern described in sporadic CJD and CSF Protein for 14-3-3, s100b and RT-QUIC findings were consistent with the diagnosis of CJD.

Over next 4 weeks his cognitive function rapidly deteriorated with progressive worsening of his myoclonus. He died 4 weeks after his hospital discharge.

There are three broad varieties of alien limb phenomenon (ALP) types described in the literature, frontal, callosal and sensory. Jerky (myoclonic) ALP is well described in patients with CJD, so CJD should be in the differentials in any patient presenting with sub-acute onset of ALP.