sulcata tortoise with back right knee too large from shell

Question
My almost 2 year old sulcata tortoise, Kanji. I don't have any idea yet which gender Kanji is.
Kanji weighs aprox 6 pounds. Is about the size of a standard pie plate.  Kanji is outside in a 15 foot by 9 foot enclosure surrounded by railroad ties during the day w/a dog house to keep cool in if needed, I live in a desert climate so this becomes essential during extreme heat.
I have a 100 gallon tank Kanji sleeps in at night. For substrate I use organic garden soil covered w/ bed a beast ground coconut shells which I keep moist to keep proper humidity in the tank.  Kanji has proper UVB lighting, heat set at 95 on warm end & 80 on cool end.
Kanji grazes outside during the day, food & water dish in tank as well.
Every morning Kanji gets a 15 minute soak daily.
Kanji's Main diet is yard grasses & weeds. Also eats plenty of mulberry leaves, grape leaves, occasional broccoli, mango & cantaloupe. Rarely (once a week) romaine lettuce as a treat.
I adopted Kanji as a 2 month old hatchling & did a lot of research before hand and have continued to study to make sure I am providing the best care possible.From the time I adopted Kanji there was a slight favoring of the right hind leg.
Lately, I have noticed very pronounced limping & lack of motivation to walk around his enclosure. Yesterday when I was bringing Kanji in for the evening I noticed that his right hind knee is too big to fit into his shell. This leg also appears to be profoundly shorter than his hind left leg.
Since this is definitely effecting his walking and activity levels I was wondering what, if anything, I should be doing about this. He appears happy. He knows his name, eats and has regular bowel movements. He enjoys basking and grazing. I just worry that this will really cause problems once he weighs 80 or more pounds.

Answer
Hi Vicki,

I think you need to take Kanji to a herp vet who specializes in tortoises.  I can't really say if there is a congenital problem, but you're wise to be concerned.  A vet can examine and x-ray the leg if necessary.  

I assume you're in Southern California.  Here's a link to the CTTC's list of tortoise vets; you should be able to find one near you.  If not, please post back and I'll see what I can do to help.