What is the diagnosis for a 90-year-old male with abnormal heel sensations and MRI brain findings of atrophy, chronic and acute left maxillary sinusitis, and right mastoid sinus effusion, 8 weeks post-fall?

Differential Diagnosis for Abnormal Heel Sensations in a 90-Year-Old Male

Single Most Likely Diagnosis

• Peripheral Neuropathy: Given the patient's age and the presence of microangiopathy suggested by brain atrophy, peripheral neuropathy is a common condition that could explain the abnormal heel sensations. The fall 8 weeks ago might have exacerbated or brought attention to pre-existing neuropathy.

Other Likely Diagnoses

• Radial Neuropathy or Other Focal Neuropathies: Although less common than peripheral neuropathy, a direct injury from the fall could have caused a focal neuropathy affecting the heel.
• Lumbar Radiculopathy: Nerve root compression in the lumbar spine, which could be due to degenerative changes common in this age group, might cause abnormal sensations in the heel.
• Diabetic Neuropathy: If the patient has diabetes, this could be a contributing factor to his symptoms, although the question does not provide information on his diabetic status.

Do Not Miss Diagnoses

• Cauda Equina Syndrome: A serious condition that requires immediate attention, cauda equina syndrome involves compression of the nerve roots in the lower spine and can cause sensory changes, among other symptoms. Although less likely, missing this diagnosis could have severe consequences.
• Spinal Cord Compression: Similar to cauda equina syndrome, spinal cord compression is a medical emergency that could present with sensory abnormalities and must not be overlooked.
• Infection or Abscess: Given the presence of chronic and acute sinusitis and mastoid sinus effusion, although these are not directly related to heel sensations, an infection spreading to the spinal cord or a peripheral nerve could cause neurological symptoms.

Rare Diagnoses

• Vitamin Deficiency Neuropathy: Deficiencies in vitamins like B12 can cause neuropathy, which might present with abnormal sensations. This would be less likely without other systemic symptoms but should be considered if other causes are ruled out.
• Paraneoplastic Neuropathy: A rare condition associated with cancer, paraneoplastic neuropathy could cause a variety of neurological symptoms, including abnormal sensations. This would be a consideration if there were other signs of malignancy or unexplained weight loss.