There are two main things that can cause rear leg parallelize, MBD or blockage/pressure pushing against the spine which pinch the nerves and prevent the legs from moving well or at all.
Metabolic bone disease typically is a result of lack of calcium in the body. The causes of lack of calcium are many. Dragon is not being exposed to sufficient levels of vitamin D3 which is needed for the body to use the calcium ingested by the dragon. Not enough calcium getting into the diet (ie via high calcium foods such as collard greens etc.) Or the diet consists also of too high levels of calcium binding agents such as oxates. (spinach has alot of this stuff hence why they do not make a good food source, despite being high in calcium as well). High levels of phosphates in the diet can do this as well.
Basking spots that do not reach sufficiently high temps to allow for proper digestion can also cause MBD. Make sure basking spots have a range of 95-115F. The dragon should be able to choose which part of that range she wants to bask in. I have seen dragons move from a basking spot of 115F down to one around 100F and anywhere in between during the course of a day. Hence a wide, inclining basking spot is best, with teh spot light shinning directly on it. Thus, the higher areas are in the 105-115F range (even if a bit higher, 115-125F is fine, as long as the dragon can move out of that heat range to a cooler area) and the lower areas in the 95-100F range.
Blockage in the stomach or intestines can also put pressure on the spine near the hips which can cause the back legs not to function properly. Depending on what is causing the blockage will determine if your dragon can regain the use of her rear legs.
Blockage can be caused by too large prey items (as your dragon is a full adult, adult crickets won't be a problem, too large prey items tends to be a problem with young dragons than adults). Ingestion of substrate is another prime reason for intestinal blackage. All calcium based sands have a high risk of causing this, crushed walnut is also well known to do this as well. Washed children's play sand has a much lesser risk but still can cause blockages if enough is ingested and the dragon isn't getting enough moisture to ensure it flushes out properly.
Other foreign matter consumed by the dragon can cause blockage as well, be it lint/fuzz or small hard objects eaten while the dragon was out of his cage and exploring, something that accidently fell into his salad bowl, or large tough stems of plants weren't all removed, can do this.
If he hasn't had a bowel movement for some time, intestinal blockage (or just plain constipation) could be the cause. First thing I would try is giving him a soak (for about 10-20 minutes) in a shallow bowl of luke warm water (around 75-80F in temp). This can help relief constipation. Adding some pureed carrot, summer squash or sweet potato will also help hydrate your dragon and get things to flow. Other things you can do is increase basking temp if they are on the low end. Cut out crickets, instead offer silkworms or hornworms (not wild caught, wild caught hornworms are toxic due to their diet. Captive bred hornworms are fed a special diet which doesn't contain the toxins found in their natural foods). Silkworms and horn worms have alot of water as well as calcium etc which can help loosen things up.
As your dragon' can't move his hind legs, when doing a soak, make sure there is something he can hang onto, such as a rolled up hand towel, your hand, or a rock/brick.
If the problem is due to MBD, make sure you have a new UVB bulb (no more than 6 months old) are feeding him calcium rich greens (see website below for a great nutritional guide on what are the best foods to feed your dragon). Dust insects with calcium powder with D3. Give her direct unfiltered sunlight, if the weather is nice enough where you are (take her outside in a container so she can bask in direct sunlight. Don't leave her unattended and make sure she has a shaded area to go to if she gets too hot.) About an hour a day for 3-4 days a week is perfect. Check yoru basking temps too, with a new digital thermometer with probe or temp gun. If you already have one, change the batteries. Low batteries may make the readings less accurate.
If her legs don't start working normally in a week or she gets worse you will need to take her to a vet. Cut out expenses elsewhere so you can pay a vet. Many vets will accept a payment plan if you can't afford to pay the cost up front.
A third cause of rear leg parallesis is a blow or injury to the spine. This is not as common but tends to happen suddenly, a fall from a basking spot, or having something heavy falling or pressing onto her back (ie stuck under a basking spot, water bowl etc while trying to get under it) can cause damage to the spine. Unfortunately there is no way to 'fix' this other than having a vet take x-rays and viewing the extent of the damage. If minor, it may go away by itself without treatment but if severe, it can lead to total paralisis and maybe even death.
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PHLdyPayne
