Gait reveals a steppage pattern favoring the right lower limb with visible foot drop. Full passive range of motion is present throughout both lower limbs. At this point, review your differential diagnosis and revise as appropriate. The physical examination shows an asymmetric pattern of weakness in the lower limbs. There is complete paresis of the right peroneal-innervated muscle groups as well as significant weakness of the right gastrocnemius muscles.
Mild weakness is noted in the right hamstring and the left gastrocnemius muscle.
Radiculopathy is excluded since this pattern of weakness is not in a segmental distribution. Given the asymmetry of the distal motor and sensory findings, a peripheral polyneuropathy seems likely, specifically multiple mononeuropathies. There is an asymmetric pattern of sensory loss, with right peroneal and left tibial nerve distributions affected. At this point, the possibility of a vasculitic neuropathy associated with SLE should be high on the differential diagnosis list and should warrant further work up including electrodiagnostic testing. The examination has excluded a central nervous system lesion.