What is the significance of below the knee versus toe-to-groin casts?
In his book, Congenital Clubfoot, Fundamentals of treatment, on pages 70-71, Dr. Ponseti states; “The foot can be maintained in external rotation only if the talus, the ankle and the leg are stabilized by a toe-to-groin (to upper thigh) plaster cast while the knee is in 90-degree flexion. In order to maintain a strong external rotation of the foot under the talus while the talus is firmly immobilized against rotation in the ankle mortise, a toe-to-groin plaster cast is mandatory The talar head will continue to stretch the tight plantar calcaneonavicular ligament as well as just the tibionavicular part of the deltoid ligament, and the posterior tibial tendon just as we stretch them with manipulation. A cast extending to just below the knee cannot immobilize the foot in firm external rotation under the talus. The reason is that since the leg of a baby is round and the anterior crest of the tibia is covered with baby fat the casts cannot be well molded and therefore will rotate inwardly w
