I have clonus and hyperreflexia.also have sjogren's, low b12 but normal mri of brain and spine.burning weak arms legs. can clonus caused by sjogrens?

Sort this out: Both sjogren's and b-12 deficiencies can cause small fiber neuropathy, which can promote limb burning. The weakness could involve large fibres, but the clonus and hyperreflexia may be a sign of upper motor neuron problem within brain or neck, and thus might require imaging studies. A few tests can be useful, such as mri, and skin punch biopsy. Although sjogren's could mimic ms, and cause clonus.

Unlikely: Neurologic issues such as clonus would be unlikely to be related to sjogren's but this is not impossible.