A 25 year old was playing basketball in a local league when he noticed that his legs were becoming uncharacteristically tired and stuff. Over the period of weeks the weakness increased even with less strenuous tasks. Except for headaches, which awakened him from sleep, he had no other complaints.
He comprehended and spoke well. The cranial nerve exam was normal except for papilledema. His sensory exam was normal; the motor exam showed normal strength and tone for both upper extremities but both lower extremities were weak, showed spasticity and there were bilateral Babinski signs.Weakness and spasticity of both lower extremities without involvement of the upper limbs indicates a midline cortical lesion where the representation of both legs are close together but somewhat distant from the arm area.
Papilledema and headache suggest increased intracranial pressure and the gradual onset of symptoms tend to rule out hemorrhage. A midline mass growing on the falx cerebri (meningioma) was diagnosed and removed.
Extended Explanation
Lesions at lower levels would give weakness and spasticity of the lower extremities while sparing the upper extremities. One such location would be the lateral funiculus of the spinal cord below T1.
The spinal cord lesion would likely include the posterior white columns producing loss of conscious proprioception, which in this case was unaffected.
The hemispheres are a more likely site since the leg area is far from the arm and motor and sensory functions are separated by the central sulcus.
