Reflex sympathetic dystrophy, also known as complex regional pain syndrome, is an rare cause of limb pain. The condition is characterize by an inciting event (trauma to the limb, damage to a nerve in the limb) which sets off a cascade of symptoms, which include burning or lancing pain in the affected limb, combined with swelling of the limb and changes in the color and texture of the skin (most commonly the skin because reddened). If you have symptoms that sound like this, then RSD is certainly a possibility and you should talk to the doctors
who are treating your condition about this.
On the other hand if you just have pain but are lacking the other symptoms, especially skin changes and swelling, then RSD is much less likely. You should consider talking with your doctors again to try to reevaluate where the pain might be coming from. For me, not knowing much about your case, with the symptoms of pain in the leg like you describe, I would think first of a pinched nerve or bulging disc in the lower back causing the symptoms. If you have not had an MRI
of the spine, that might be an option. Another possibility would be bad arthritis
of the hip, which can often cause pain in the entire leg.
Start by talking with your doctors again!