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I read your question carefully and I am sorry about the distress you seem to be in.

From what I understand the doctors do not think that the issue stands with the knee itself, but rather in the nervous system which is responsible for commanding movements in your limbs. So its involvement would affect limb movement and can at times be mistaken for an issue of the joint. The MRI of the knee has excluded knee problems, while the MRI of the head has revealed multiple brain lesions probable in the setting of multiple sclerosis.

Multiple sclerosis is a chronic neurologic disease, appearing typically at your age, with multiple lesions of the brain and spine white matter which could well justify your walking difficulties and increased reflexes. It is not a life threatening disease, but it causes disability which increases with time as the number of lesions increases. These days many several new therapies are being developed to slow down its progression, time will tell how effective they are.

The other alternative the MRI suggests is that these white matter lesions are remains of an infection or inflammatory condition. It is unclear in your query what do you mean by still having vertigo and viral meningitis. Have you been diagnosed with viral meningitis recently? How was it diagnosed did you have tests like MRI or lumbar puncture? Did your problems with the knee present after that, or were they present before? The answers to these questions might be helpful. It might also be helpful in case you have the head MRI report if you could upload it here, so that I can create a better impression on the findings.

Anyway for now I believe the next diagnostic steps will be a spine MRI to look for lesions there, as well as a lumbar puncture. Those tests should establish the precise diagnosis among the possibilities above and then proper treatment can be initiated.

I remain at your disposal for further questions.

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Thank you for the MRI report. I must say that the rest of your story is not very clear however, I find it difficult to understand the timeline, whether you are relating about when you were diagnosed with viral meningitis or about your recent history. It doesn't make it any easier to understand neither how the viral meningitis was diagnosed nor what in your recent history led the doctors to the head MRI.

The MRI report was very useful. The description of those lesions looks compatible with multiple sclerosis. Some of those lesions are probably active which would speak against old lesions from the past viral meningitis and is in the favor of multiple sclerosis.
The examination is not complete though as it was performed without contrast. Given the findings another MRI this time with contrast administration is necessary to confirm the presence of new active lesions which would indicate multiple sclerosis. As I said before lumbar puncture with cerebrospinal fluid analysis will be necessary as well.

As for your question of how long it will take you to be as before, while I understand your wish to be back as you used to be, you must realize that if multiple sclerosis is confirmed it is a chronic disease. It has no cure, there is no medication which reverts the lesions already there. The aim of the treatment would be to slow done disease progression in the future. But let's not get ahead of ourselves, as I said more exams are needed before.

I hope to have been of help.

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At times different patients mean different things by twitching so it depends.

In the most common use, meaning small muscle contractions. That type of twitching is not related to brain injury. Most often it is a question of anxiety, but at times some electrolyte abnormalities, thyroid dysfunction or vitamin B12 deficiency (which might produce brain lesions as well) might be the cause, easily excluded by some simple routine blood tests though, might already have done them, if not probably the neurologist will request them.

In your case though it might be a question of clonus as well, often associated with the increased reflexes you report. Clonus is a series of involuntary, rhythmic muscle contraction and decontraction in the limbs. It is common in any disease interrupting nerve pathways coming from the brain (as those lesions on MRI can do), as the brain is unable to properly exercise its control on the spine, hence the increased reflexes and clonus.
Another possibility would be a partial seizure, but since you describe it as all around your body it's unlikely.

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