The illness of Rickets is present in young dogs due to the lack or deficiency of calcium or vitamin D. It is characterized by a tendency toward the formation of long bones in the legs. You will notice bone swellings developing in the extremities of the long bones.There is a tendency in puppies for the long bones to arch outwards due to the pressure of the body weight. In more advanced cases, the complete bone structure is deteriorated, and the dog has a lot of difficulties getting around. The lack of sunlight is also a contributing cause of rickets, as well as a bad diet. In order for the animal to recuperate, he must be under veterinarian treatment. The case can worsen notably, leading to an irreversible state.
I would take him to the vet. He needs vitamins and sunlight. If he's inside you can put the crate by a window or open door. The light needs to shine directly on him for a while. Since I raise my puppies and any that I keep in the house, I have an exercise pen that I put on my front porch for them to have outside time from the time they are about 4 weeks old.
Over the years, raising numerous litters, we've found this to be a much bigger problem when feeding higher end puppy foods. Yes, they need sunlight to utilize Vit D that plays a role in all this, but I think the bigger issue is improper ratios of calcium & phosphorus in the dog food. For this reason, we found just good old Puppy Chow to be the best to raise pups on and to NOT have the "rickett's" bone disease issues.
So not sure what you are feeding, but I would switch up to Puppy Chow, let them get some sun.
This is also the reason some food makers have a large breed puppy vs a regular puppy food.......to further restrict and more closely manage the mineral content of the food to keep these "growth diseases" from appearing.
Be sure to get that pup checked out by a professional, and give a good multi vitamin and consider a tums (or 1/2 or 1/4 depending on size of pup... your veterinarian can tell you how much is safe) along with it for a while, along with a good quality puppy food Good luck!!
High doses of vitamins A,D, and E. One of the best sources is wheat germ oil. Also make sure they get plenty of sunlight and exercise. If you catch it early enough, you can treat it and straighten them right out.
Treeblazin said it all cod liver oil for a week lay off a week and give it for a week as far as a vet they will tell you there is no such thing as rickets in a dog had a pup with it at 7 weeks put her on the cod liver oil she is 7 mths old now and a UKC show champion