S90-S99 — Injuries to the ankle and foot
ICD-10-CM codes S90-S99 cover injuries to the ankle and foot, within injury, poisoning and certain other consequences of external causes. The block holds 4,342 codes across 10 categories, of which 3,324 are billable and 1,018 are header codes that cannot be submitted on a claim. 4,341 of them (100%) require a 7th character.
The 7th character in S90-S99
A code in this block is not complete without its 7th character, and a missing one is a rejected claim rather than a denied one: the clearinghouse never passes it on. 4,341 of the 4,342 codes here take one.
- A
- initial encounter
- D
- subsequent encounter
- S
- sequela
Risk adjustment in S90-S99
0 codes in this block map to a CMS-HCC, which means the diagnosis carries a risk-adjustment payment when it is documented and coded. Under-coding here is money left on the table; over-coding here is what audits are for.
- HCC 405 Traumatic Amputations and Complications
What else to watch in S90-S99
- 2,680 codes are laterality-specific. They come in left and right pairs, and the pair is mutually exclusive on a single site: coding both without a bilateral code is a contradiction a scrubber should catch before the payer does.
- 2,329 codes are named in Medicare coverage policies. An LCD or NCD lists them as supporting medical necessity, or explicitly as not supporting it. Which applies depends on the MAC for your state.
Categories in S90-S99
- S90Superficial injury of ankle, foot and toes
- S91Open wound of ankle, foot and toes
- S92Fracture of foot and toe, except ankle
- S93Dislocation and sprain of joints and ligaments at ankle, foot and toe level
- S94Injury of nerves at ankle and foot level
- S95Injury of blood vessels at ankle and foot level
- S96Injury of muscle and tendon at ankle and foot level
- S97Crushing injury of ankle and foot
- S98Traumatic amputation of ankle and foot
- S99Other and unspecified injuries of ankle and foot