S99.021PSalter-Harris Type II physeal fracture of right calcaneus, subsequent encounter for fracture with malunion

S99.021P is the ICD-10-CM diagnosis code for Salter-Harris Type II physeal fracture of right calcaneus, subsequent encounter for fracture with malunion. It belongs to category S99 (other and unspecified injuries of ankle and foot), block S90-S99 (injuries to the ankle and foot) and chapter 19 (injury, poisoning and certain other consequences of external causes). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

The 7th character "P" means subsequent encounter for fracture with malunion: use it for encounters after active treatment, while the patient is healing or recovering.

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 949 (Aftercare with CC/MCC, relative weight 1.123) and DRG 950 (Aftercare without CC/MCC, relative weight 0.7664), in MDC 23 (Factors Influencing Health Status and Other Contacts with Health Services), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It is exempt from present-on-admission (POA) reporting, so no POA indicator is required.

It was added in FY2017, effective October 1, 2016.

Before ICD-10, this condition was coded in ICD-9-CM as 733.81 (malunion of fracture).