Leg "disappears" when walking

[KAB58]

Greetings,

Has anybody heard of this?  My wife, for months, has been dealing with the following condition.  She can be walking along and she just collapses.  She describes it as if her knee just disappears.  After she collapses to the ground is able to immediately get back up and walk again.  It happens at least 10-15 times a day.  Its does not seems to happen when she is baring weight such as carrying our child.  It does not happen walking up stairs or when she tenses or leg when she is walking.  It is guaranteed to happen the first step she takes after she exercises (stationary bike).  She has had the following test and seen the following doctors and is on the following medications:

Medications: 1) Lamictal, 2) Abilify and 3) Lorazipam (All for depression/anxiety)

Doctors: GP, physical therapy, neurosurgeon, orthopedic doctor, neurologist (current one she is working with)

Tests: Blood work (normal), EMG (normal), MRI - Brain (normal), MRI – C-spine (normal), MRI - Lumbar (normal), Spinal tap (1st half came back normal which basically ruled out the BIG ones like MS).

Any ideas?  We are desperate!!!!

[KAB58]

So this issues was resolved without trying you can say.  It was brought on by excess stress and anxiety.  After my wife went on, in her case, Abilify, her leg issue went away.  Apparently her brain was coping by making her leg give out.  Sounds very odd but is very true.  Would not exclude stress and anxiety even if you don't think you have any?  Does your leg go out when your doing anything that would cause you to be injured such as when your going up or down stairs, if you have a child, holding the child, etc?

[melynamarie]

your dilema sounds very similar to mine. I also loose my knee quite frequenty. I haven't seen a doctor yet, though. it took a bit of searching to find anything that sounds similar to my situation. I only have one question. Does it cause you a lot of pain. it doesn't hurt when my knee goes out. I does feel really weird. Mostly I'm embarassed especially at work. My co workers are starting to mimic my little bob as i catch myself before i fall.

[KAB58]

I will research each of these...

[KAB58]

Thanks.  Thats the big delima we face, not other symptoms.  MRI's, EMG's, Knee x-rays, spinal taps, blood results are coming back normal.  The symptom is a constant, the only other thing is just that she can make it happen at will if she exercises.  Frustrating.

Thanks txsilver

[txsilver]

Nothing specific in mind, but I think it is easier to get an idea of what is going on if you have more than one symptom, but not too far to the other extreme either.  I tried to get a little info on just the one symptom and here is what I found as possible causes.

Knee locking - a locked knee may cause a collapse, or may be a related condition.
Knee ligament damage
Recurrent patella dislocation - may cause knee locking or knee collapse
Discoid lateral meniscus - may cause knee collapse
Chondromalacia patella - occasional locking or knee collapse.

[KAB58]

Thanks for the clarification.  Anything with potential we will explore since nothing is showing up on anything.

Much appreciated

[KAB58]

The "disappearance" mainly was focused on an area about 2" below and above the knee.  In the last couple days the feeling has progressed from he knee up to her hip.  In the last couple days she has been complaining about being fatigued also.  She is pretty stoic so sometimes its hard to get things our of her.  Did you have anything specific in mind?

Thanks for you time.

[lazydog]

Well mainly the first step was the biggest problem.  She first noticed it playing golf...that it just "disappeared" on her....like you describe...and got worse fairly rapidly.
...Julia

[txsilver]

What other symptoms does she have?  I do not have my knee collapse as often as she does, but I have had it happen and know the misery of it.

[KAB58]

Thanks so much for taking the time to read my post.  I will certainly bring this up to the Dr..  What symptoms sound familiar to you?  Thanks!

[lazydog]

Have they tested for Paget's disease of the bone?  My mother has this and sounds like very similar symptoms.
...Julia