Brief Answer:
Rather a lot of possibilities.

Detailed Answer:

Hi,

Several features of pain can be helpful in clarifying what is going on and the next steps for diagnosis and treatment.

Type of pain. Burning mostly means a nerve is having problems. This can be either a sick nerve or a nerve that has had an injury. Electrical, shooting would be others implying nerve source for pain.

Location of pain. There is a lot to this. First, if something goes in the pathway of a nerve, then that is the nerve involved. Nerves are long and the pain is in a belt-like long pathway. Smaller areas are smaller nerves. This also tends to say what might be going on. Obviously, if there was an injury to the area and then there was pain outward from it "hit a nerve" would be a possibility. Sick nerves are there in Multiple areas and tend to be the TIPS of the nerve, not the whole nerve

What hurts. Moving a particular way that triggers the pain tells what is hurting. Specifically, it can distinguish outward structures like skin, muscles, tendons, joints from deep structures like organs and nerves.

``     Having a diagnosis leads to the choice of medicine for the pain. Inflamed outer structures respond to treating inflammation. Inner structures need diagnostic tests because something internal is broken. MRI's.

And, structures that cannot be fixed need adaptations. Physical therapy, pillows, supportive structures internal and external.

So, for arthritis, there are medications for inflammation such as Ibuprofen and other aspirin-like drugs. Physical therapy, heating pads are probably some of the MOST important modalities especially aqua-therapy.
OK, you've done all of that. Evaluation by an orthopedic surgeon is another option.

Joint replacement often is helpful for severely deformed joints.

Regards

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