Differential Diagnosis for 62 yo Female with Perineal Pain, Hip Pain, and Muscle Weakness

Single Most Likely Diagnosis

• Lumbar Radiculopathy: The patient's symptoms of perineal pain, hip pain, and muscle weakness, combined with the MRI findings of left-sided asymmetric disc bulge, subarticular recess stenosis, and mass effect on the L5 nerve root, strongly suggest lumbar radiculopathy. The presence of foraminal stenosis and postsurgical changes also supports this diagnosis.

Other Likely Diagnoses

• Failed Back Surgery Syndrome (FBSS): Given the patient's history of bilateral laminectomy and postsurgical changes, FBSS is a possible diagnosis. The presence of postsurgical enhancement within the epidural space and asymmetric surrounding of the left S1 nerve root also supports this diagnosis.
• Degenerative Spondylosis: The MRI findings of mild to moderate spondylosis, degenerative endplate changes, and Schmorl's node at T12 suggest degenerative spondylosis as a contributing factor to the patient's symptoms.
• Foraminal Stenosis: The moderate left-sided foraminal stenosis with mass effect on the exiting L5 nerve root is a significant finding that could be contributing to the patient's symptoms.

Do Not Miss Diagnoses

• Cauda Equina Syndrome: Although less likely, cauda equina syndrome is a serious condition that requires prompt attention. The patient's symptoms of perineal pain, hip pain, and muscle weakness, combined with the MRI findings of mass effect on the L5 nerve root, warrant consideration of this diagnosis.
• Spinal Infection: The presence of mild edema suggested in posterior disc material and postsurgical enhancement within the epidural space raises the possibility of a spinal infection, which would require urgent attention.
• Spinal Tumor: Although rare, a spinal tumor could be causing the patient's symptoms and MRI findings, and it is essential to consider this diagnosis to avoid missing a potentially life-threatening condition.

Rare Diagnoses

• Arachnoiditis: This is a rare condition characterized by inflammation of the arachnoid membrane, which could be causing the patient's symptoms and MRI findings.
• Spinal Stenosis with Neurogenic Claudication: Although the patient's MRI findings do not show significant canal stenosis, this condition could still be considered, especially if the patient's symptoms worsen with walking or standing.