Yes, that does look like some of the pictures I have seen of osteopetrosis. It is thought to be related to avian lymphoid leukosis. Here are some threads with pictures and other links:
I know this is a late response, but wanted to post in case others came across this thread.
I agree that the first bird pictured in this thread almost certainly has a disease called avian osteopetrosis (= thick leg disease), which is caused by avian leukosis virus. As avian osteopetrosis (AOP) progresses, the bird's legs will begin thickening in the middle, and eventually become football-shaped. The thigh and wing bones may also be affected in the same ways. It is basically bone tumors growing out of control.
Some questions that would help diagnose AOP:
- Are the swellings hard to the touch? (AOP: yes; soft tumors or swelling will be squishier)
- Are the swellings cool/normal temperature to the touch? (AOP: yes, usually; hot swellings indicate inflammation)
- Did they seem to start in the center of the lower leg and move towards the joints? (AOP: yes; broken or infected bone could be anywhere)
- Did they appear in the left and right leg around the same time? (AOP: yes, although the size of the swellings can vary between right and left, they should be present on both sides)
If it is AOP, you can expect:
- new swellings on the thigh bones, feet, and wing bones (harder to see but you could feel them)
- these will start in the middle of the bones and move towards both joints
- for the same bone (i.e., just looking at the upper wing bone or the foot), swellings will present on both the left and right sides of the body around the same time
- the new bone tissue is weaker than normal bone, so it is easier to fracture
- progressively reduced mobility to immobility
Because AOP is transmitted virally, it is very important to separate infected birds from the rest of your flock, and especially from chicks, who are highly susceptible to the virus. If you obtained an infected bird recently, there is a strong possibility that it was already infected when you got it. We don't know how extensive this virus can be transmitted across different bird species, but it seems to be most common in chickens and turkeys. Because it results from a virus, antibiotics are unlikely to do anything helpful for AOP.
I am a researcher at Des Moines University (Iowa) who studies the origins and history of this disease in birds. If you think one of your birds might have AOP, please contact me via pm on this forum or by email at firstname.lastname@example.org. I am interested in obtaining euthanized birds for research, so that healthy birds do not have to be infected to study how this disease affects the skeleton.