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Lizard With Metabolic Bone Disease

My bearded dragon will not move at all. When it does move, it can only move its front legs. What is wrong?

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I bought two bearded dragons last Christmas. One has always been larger than the other and fairly active (as active as they can be), whereas the other one barely moves, has always been a lot thinner and looks weak. At first I thought the bigger one ate all the food, so at meal times, I would separate them. However, recently the small one will not move at all. When it does move, it can only move its front legs. It has never been roughly handled so I can’t understand it. I’m taking it to the vet soon, but do you have any ideas about what could be wrong?

Your smaller beardie is really in trouble and I’m glad that you are taking it in to see a vet soon. You are calling them both “it” so I don’t know if you don’t know the sexes or if they could both be two males. It is not a good idea to house males together, nor is it a wise idea to house beardies of differing sizes together.


I would like you to go back into the archives and read about the proper husbandry of these lizards. They need a very hot basking area (110 degrees Fahrenheit) and a cage gradient of 80 to 90 degrees Fahrenheit). You didn’t give me any information about your UV lighting (they really need UVB), and with most sources of ultraviolet light, the bulb must be changed regularly (every 6 to 9 months or as recommended by the manufacturer). Sunlight, unfiltered through glass or plastic, is also very beneficial. A vitamin/mineral supplement containing calcium is also a good way to ensure a more balanced diet (but this is something that should be discussed with your herp vet). Crickets should be gut-loaded. In addition to vegetables and insects, a portion of the diet should also contain a commercial bearded dragon food.

My suspicion is that your smaller beardie is suffering from the ravages of a form of metabolic bone disease (MBD). I have discussed this several times in my column. Please have a look in the archives so you can read more about this disease. It usually occurs when a reptile (or other creature) does not receive proper UVB lighting and/or calcium in the diet. The calcium level in the bloodstream must remain within a certain narrow range for the animal to function normally, so it draws calcium out of the bones. As the bones become weaker, spontaneous fractures may occur. Lizards may begin dragging themselves when they ambulate, instead of lifting themselves up to walk or run. Eventually, the spine may become affected, causing rear-limb lameness or even paralysis. This sounds a lot like what you are describing to me.

It is weird that two lizards, housed the same way and fed the same way, will react differently. One may acquire a metabolic disease from lack of ultraviolet light and calcium, and the second one may appear perfectly fine (although internally, it may also be developing signs of MBD, albeit, much more slowly).

So, yes, please take your beardie in to see a herp vet as soon as possible. Your vet may need to draw blood to check the calcium and phosphorus levels. Radiographs (X-rays) may need to be taken. Other tests may also need to be performed. Your bearded dragon may need extensive treatment, and even then, the damage to the nerves of the spinal cord or limbs may be permanent. Also, you must commit to changing your lizard’s environment and husbandry or this can occur again.

I am sorry to be the bearer of bad news, but a lizard dragging its hindquarters and pulling itself along by its front legs is not a good situation, and one that may not be able to be completely reversed. I hope your vet can help you figure out exactly what is wrong with your smaller beardie and provide the correct treatment to stabilize it and allow it to heal.


Margaret A. Wissman, DVM, DABVP has been an avian/exotic/herp animal veterinarian since 1981. She is a regular contributor to REPTILES magazine.

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