Podiatry Coding & Billing Alert

Question: How do we report the encounter when a patient presents with orthotics required for correcting problems associated with flat foot? Will payers reimburse the encounter or do we need to get an ABN going forward? 

Kentucky Subscriber

Answer: “Most insurance companies exclude treatment for flat feet unless there is pain and other associated problems due to the condition,” says Arnold Beresh, DPM, CPC, CSFAC, of Peninsula Foot and Ankle Specialists PLC in Hampton, Va. When a patient suffers from flat foot (also called pes planus or colloquially known as fallen arches), this means that the arch, or medial border, of his foot collapses, with the entire sole of the foot coming into complete or near-complete contact with the ground.

In ICD-10-CM, you should report this condition with one of three codes:

• M21.40 — Flat foot [pes planus] (acquired), unspecified foot
• M21.41 — ... right foot
• M21.42 — ... left foot
• Q66.50 — Congenital pes planus, unspecified foot
• Q66.51 — … right foot
• Q66.52 — … left foot.

Note the ICD-10 change: While you used to have one ICD-9 option for flat foot, ICD-10 gives you three more based on anatomical site (right foot, left foot, and unspecified).

Documentation: Your physician most likely already documents the side of the flat foot, so now have you a way of specifying this with a diagnosis code. Although you have a code for unspecified, you should always code to the highest specificity.

Coder tips: Underneath the M21 (Other acquired deformities of limbs), you’ll find the following notations:

Excludes1: Acquired absence of limb (Z89.-), Reduction defects of limbs (Q71-Q73), and congenital deformities and malformations of limbs (Q65-Q66, Q68-Q74)

Excludes2: Acquired deformities of fingers and toes (M20.-) and Coxa plana (M91.2).

Underneath the M21.4 (Flat foot [pes planus] [acquired]) category, you’ll find an Excludes1 note that prevents you from reporting these conditions with congenital pes planus (Q66.5).