I have 2 adult tiels and each one has a foot like Adelie's. Both were seen by Dr. Sakas, in fact Chickpea had been injured in an attack by another fid and spent several days at the vet hospital. They had been able to straighten out her foot and had it taped in a normal position but once she came home and the tape was removed her foot folded so all her toes face forward. The vet had said it might happen due to muscle injury caused in the attack.
Baldie has a similar situation but I have no background on what happened. He'd been sold to a bird owner friend (not on AA) but 2 weeks later she gave him back. He'd obviously been attacked by something larger and literally had a hole in his right leg just above the foot. He was treated by the vet and had his foot taped plus had to wear a cone. His leg eventually filled in but once the bandages were removed from his foot the toes were facing forward. The foot atrophied just like Chickpeas and can't really be used.
In spite of that though, both Chickpea and Baldie can perch both on flat surfaces, perches and platform perches. In fact, Chickpea and her OH sleep on the frame of one of the pictures hanging in the bird/family room. They stick together as a couple. Both Chickpea and Baldie are "hands off" tiels due to having been treated and medicated when they were young.