Can osteoarthritis be misdiagnosed from an x ray?

I am having the usual blood tests now as I suspect I may have other problems, but a recent foot x ray result came back showing 'early signs of osteoarthritis'. I am only 26 so naturally, I am worried. My GP does not seem too concerned, but the pain from the base of my big toe was terrible a few months ago (still not great but much better that I have been resting). Is it at all possible that this is a misdiagnosis? Could it be reactive arthritis instead?

Osteoarthritis is a type of arthritis that is caused by breakdown of cartilage, with eventual loss of the cartilage of the joints. Cartilage is a protein substance that serves as a "cushion" between the bones of the joints. When the cartilage deteriorates (degenerates), the bone next to it becomes inflamed and can be stimulated to produce new bone in the form of a local bony protrusion, called a "spur."

A very common early sign of osteoarthritis is a knobby bony deformity at the smallest joint of the end of the fingers. This is referred to as a Heberden's node, named after a very famous British doctor. The bony deformity is a result of the bone spurs from the osteoarthritis in that joint. Another common bony knob (node) occurs at the middle joint of the fingers in many patients with osteoarthritis and is called a Bouchard's node. Also common in feet.
I have some very good pictures which would show you how easy it is to spot on an x ray but unfortunatly they will not copy.

What you see is the 2 bones with a usual gap(filled with cartilage, but when ostearthritis is present there is either a very narrow gap or no gap at all so the pain is of bone rubbing on bone as the cartilage cushion has gone flat.

I am sure you get the picture but a good idea would be to ask to see your xrays and I am sure your consultant will explain to you what they see and it will become clear.
good luck.

Why did you get the X-ray in the first place?
If you had trauma to that foot, then it could look like osteoarthritis. Even though you are young, Id ask your doctor if he/she thought it could be gout? (there is a blood test for that)
Reactive arthritis happens if youve had an infection (strep, gonorrhea, ect) that later your immune system reacts againts.

generally in my experience of ortho surgery, after working an orthopaedic outpatients clinic, the consultants use x-rays as well as thorough non invasive examinations as the gold standard for diagnosis, these x-rays will also be used during surgery, to pinpoint exactly where they should be operating, so generally misdiagnosis from x-rays is rare.

To the trained eye you can spot it from x-ray at the blink of an eye.

Don't worry, surgery especially at 26 is the last resort, your doctor/consultant will prefer to use a non surgical option first, maybe physio or medication (glucosamine) or a brace or maybe all 3. steroid injections can ease the pain and make you feel excellent for a while.

hope this helps put your mind at ease a little,