Diabetic amyotrophy usually presents with a painful asymmetrical proximal motor neuropathy affecting the lower limbs. Less commonly it is symmetrical. It is thought to be caused by the occlusion of the vasa nervorum of the proximal lumbar plexus and/or the femoral nerve causing infarction. The initial presentation is with pain in the thigh. This is followed by wasting and weakness of the quadriceps and loss of the knee jerk.
It is an example of a multiple mononeuropathy; the onset is often associated with poor diabetic control and may improve with good control.
Last reviewed 01/2018