What's a natural way to treat congenital malformation?

Prevention. There are no "natural" remedies to correct a congenital malformation - which is a deformity ro maldevelopment of a part of the body. If there are symptoms, there are some natural ways to relieve them, but correct of a malformation usually requires surgery or artificial substitution.
Limb difference. In the upper extremity we like to call these limb differences. Natural can mean "do nothing" and there are some cases this may be best limbdifferences.Org is a resource for families and friends of children with limb differences. And there are many regional support groups such as www.Littlefins.Org little fins limb difference group - a support group of families located in the twin cities, mn.