Progressive collapsing flatfoot deformity can be classified according to the severity of the deformity, as well as the underlying cause. There are several classification systems used by healthcare providers to describe the different stages of the condition. Here are two common classification systems:
- Johnson and Strom’s classification system:
- Stage I: The foot is flat when bearing weight, but the arch returns when the foot is lifted off the ground.
- Stage II: The arch does not return when the foot is lifted off the ground, but the foot is still flexible.
- Stage III: The foot is rigid, and there is significant arthritis and deformity.
- Myerson’s classification system:
- Stage I: The hindfoot is in a valgus position (tilted outward) and the arch is slightly flattened.
- Stage II: The hindfoot is in a valgus position, the arch is more severely flattened, and there is evidence of instability in the ankle joint.
- Stage III: The hindfoot is in a valgus position, the arch is severely flattened, and there is significant ankle joint arthritis.
The classification system used will depend on the healthcare provider’s preference and the specific needs of the patient.