I am sure we have all experienced spraddle-legged youngsters in the nest. Here one or both legs splays outward producing a deformity in the leg or legs. The deformity is mainly in the ability to position the limb in a proper posture; but can also result in true deformed bones or joints of the involved leg(s).
The condition results from insufficient traction in the nest bowl. It happens most commonly when there is a single nestling. The second nestling usually provides something to push against for the other nestling, and the side of the nest bowl provides the same thing for the opposite leg.
The nesting material is the other factor in providing adequate traction to the growing squabs. The parents usually cover the squabs providing extra weight for them to bear, and if adequate traction is not present, the leg or legs tend to push away from the body producing this condition.
The involved leg can end up pointing 90 degrees or more away from what would be normal. I have even seen them where the rotation was so severe that they appeared to be pointing backwards. Of course the longer before they are noticed, and the worse the deviation, the harder it can be to correct the problem.
This can usually be corrected by the fancier. First, adequate nesting material to provide decent traction needs to be supplied. The legs then need to be “hobbled”, or bound together to approximate a near normal or slightly overcorrected posture.
One must be careful not to attach the binding material too tightly around the racing pigeons legs so as not to disturb circulation. A relatively soft material is better, so as not to cut into the leg tissue since there may be quite a bit of tension on the legs/material. I have used soft twine or tape to do this job, often using the band as a starting point, attaching to the band rather than the leg to distribute the pressure more evenly.
Next bind the other leg to pull them together without constricting the leg. It usually only takes several days to a week or so to accomplish the correction since the squabs are growing so fast at this time. Remove the binding when it seems to be time and see how the squabs leg posture appears.
One can always reapply it if it is not corrected adequately. Some may not be completely correctable depending on severity and timing on the corrective process. The success rate is high and certainly deserves trying.
See also Treating Pigeons with Spraddle Legs
Spraddle Legged Pigeons by Dr. David E. Marx DVM