Carpal Tunnel Syndrome: Although EMG/NCV tests are normal, carpal tunnel syndrome can sometimes present with normal electrophysiological studies, especially in early or mild cases. Clinical examination and symptoms such as nocturnal numbness, tingling, and Phalen's or Tinel's sign can support this diagnosis.

Thoracic Outlet Syndrome: This condition can cause numbness and dexterity changes in the hands due to compression of the brachial plexus. Normal EMG/NCV and MRI cervical spine do not rule out thoracic outlet syndrome, as the compression often occurs at the thoracic outlet.
Radial or Ulnar Neuropathy: Focal neuropathies can cause numbness and dexterity changes. While EMG/NCV might be normal if the neuropathy is mild or recent, clinical examination can reveal specific patterns of weakness or sensory loss.
Cervical Radiculopathy with Normal Imaging: Sometimes, cervical radiculopathy can present with normal MRI findings, especially if the pathology is dynamic or if there is a component of foraminal stenosis not well visualized on static MRI images.

Multiple Sclerosis: Although less common, multiple sclerosis can present with bilateral symptoms and normal initial imaging and electrophysiological studies. It's crucial to consider this diagnosis due to its significant implications for treatment and prognosis.
Vitamin B12 Deficiency: A deficiency in vitamin B12 can cause neurological symptoms, including numbness in the hands and feet, and can be associated with normal EMG/NCV and imaging studies.
Diabetes Mellitus: Early diabetic neuropathy can present with bilateral hand symptoms, and EMG/NCV might be normal in the early stages. Given the prevalence and importance of diabetes, it should not be missed.

Amyloidosis: This condition can cause peripheral neuropathy, which might present with bilateral hand numbness and dexterity changes. However, it is relatively rare and usually associated with other systemic symptoms.
Sjögren's Syndrome: This autoimmune disorder can cause peripheral neuropathy among its myriad presentations. While rare, it should be considered in patients with suggestive symptoms or other systemic manifestations.
Paraneoplastic Syndromes: These are rare neurological disorders caused by the immune response to a cancer, and they can present with a variety of neurological symptoms, including neuropathy. Given their potential for serious underlying disease, they should be kept in mind, especially in patients with risk factors for cancer.