Burning pain, numbness, in feet and toes.. what is this, also chronic. can hardly walk left knee givs out also?

Hard to say: But chronic sensation changes , burning sensations, and ?Motor deficits can be serious. Check in with your doctor and maybe a neurologist for an evaluation.

Numbness: Burning, numbness, tingling can be caused by many things. Nerve damage can be mechanical (pinched nerve) or metabolic like diabetic neuropathies. Your doctor will have to evaluate the causes. The number one cause of parasthesias is diabetes. Elevated sugar levels cause damage to the covering of the nerve causing over stimulation of the nerve creating the burning and tingling.

Possible nerve: Consider peripheral neuropathy, especially small fibre variation, but also pinched nerve at ankle such as tarsal tunnel syndrome, and wonder about more proximal nerve issues causing distal symptoms. Emg testing or skin punch biopsies may reveal answers. Start with neurological exam, and have your doctor guide the workup.

Get Checked!: Symptoms like these especially if in both feet and toes is highly suspicious for diabetes. Other serious diseases can also account for your issues. You can expect to have blood work, as well as a thorough physical examination for starters. Depending on what they show will determine any other diagnostics are done. Don't delay!