Knee pain from back?

I've had intermittent bilateral medial knee pain for 3 years without a diagnosis after seeing 4 doctors. The pain appears to be neurological (MRI is normal), it never occurs in both knees at the same time, and comes and goes seemingly at random. I've also had back problems with decompression surgery at L5-S1 in 1990 and again in 1996 with current nerve impingement at L4-L5 and L5-S1. I'm looking at a spinal fusion at L5-S1 soon with severe low back pain and some numbness in the foot (minimal sciatic pain).

I'm wondering if my knee pain could be referred pain from the back. I've heard numerous anecdotal stories about such referred pain, but none of the doctors I've talked with are willing to acknowledge that such a thing exists. It seems to me that either referred knee pain from the back is anatomically possible, or it isn't, and the medical community should have a definitive answer to that. And, if it is possible, what is the mechanism which triggers it?

My symptoms appear consistent with, for example, saphenous nerve entrapment which can mimic orthopedic knee pain, and this actually makes some sense since the saphenous nerve is a branch of the femoral nerve which arises from the L4 nerve root. Why have none of the doctors suggested this, or referred me to a neurologist for testing to rule that out? Are there other possible etiologies for referred knee pain from the back which could make sense with lower lumbar nerve involvement?  

[dr_simran]

Hello Lonzo

It seems you might be having some neural compression which sends out a referred pain to the back.
Often it is very difficult to pin point on any specific nerve as the exact cause of the nerve pain.
It could be also sciatica where the pain is also on the knee joint.
What are the current medications you are taking? How is the pain precipitated? Answers to these questions would further help.

Best.
Take care