I suspect the Dragon has MBD. Metabolic Bone Disease is a result of lack of calcium, the lack of UVB light to metabolize the calcium, or improper diet where the calcium is being bound by improper diet.
The basking area should have 105*-110*F, warm side 80's and the cool side of the tank in the 85* range. This is imporatnt for digestion and passing of stool. If the temps are not correct, this can also cause a problem.
You need to have a day time basking bulb as well as a UVB. I recommend a Reptisun 10.0. The UVB bulb is needed to stop Metabolic Bone Disease. Since the Dragon is in such bad shape, in this case I would reccommed a Mercury Vapor Bulb, which has a higher output of UVB rays and would replace the basking bulb and a UVB tube.
On a side note, the UVB needs to be changed every 6 months.
Normally a UVB should be a tube type.
I would change the Coil light to an MVB bulb asap. The Power sun is an excellent MVB bulb.
TheCoil UVB bulbs can injure the eyes.
Compact UVB problems: http://www.uvguide.co.uk/phototherapyphosphor-info.htm
The UVB bulb or MVB bulb should not have any plastic between it and the Dragon,it should not be no more than 12" from the Dragon. The lights should run daily for 12-14 hours a day.
Normal diet is Collard greens, mustard greens, dandelion greens, escarole and curly endives. Butternut squash and various berries are great for a treat. The Veggies should be put in fresh daily, and done about an hour after lights on. They need 20% veggies daily and 80% live prey under a year old and over a year old we reverse the percenatges to higher veggies and less prey. The Kale can bind calcium as can spinach No Lettuce as it is all water and has no nutritional value! It can casue serious dehydration by causing diarrhea. This is a nutritional chart that will help to give the proper ratio of calcium to phosphorus: http://www.beautifuldragons.com/Nutrition.html it is color coded for easier reading.
The Dragon will need to get on a good Plain Calcium supplement 5 days a week and a Vitamin 2 days a week. It will have to see a Herp Vet for blood work and a get started on a Calcium and Vitamins from the Herp Vet. This is some information on MBD: http://exoticpets.about.com/cs/reptilesgeneral/a/metabolicbd.htm
I suggest you also get the proper lighting and if the Dragon is not in a 40 gallon breeder tank that will also be a must to help the Dragon.