Posterior tibial tendon rupture: a refined classification system.

Since Johnson's and Strom's classification system in 1989 an increasingly complex array of deformities of the foot has been recognized in association with PTTR. This wide spectrum of deformity is not completely addressed by the current classification system, nor does it leave sufficient room for variation within a given treatment stage. Taking into account ankle and hindfoot valgus, forefoot supination, forefoot abduction, and medial column instability we present and discuss a refined classification for PTTR. Potential treatments for each stage are provided.