Skip to main content
ICD-10/S82.66XN

S82.66XN ICD-10-CM Code: Nondisplaced fracture of lateral malleolus of unspecified fibula, subsequent encounter for open fracture type IIIA, IIIB, or IIIC with nonunion

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Inpatient Payment Groups (MS-DRG)

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43.0 (FY2026), Appendix B.

  • MS-DRG 564 — OTHER MUSCULOSKELETAL SYSTEM AND CONNECTIVE TISSUE DIAGNOSES WITH MCC (MDC 08)
  • MS-DRG 565 — OTHER MUSCULOSKELETAL SYSTEM AND CONNECTIVE TISSUE DIAGNOSES WITH CC (MDC 08)
  • MS-DRG 566 — OTHER MUSCULOSKELETAL SYSTEM AND CONNECTIVE TISSUE DIAGNOSES WITHOUT CC/MCC (MDC 08)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Code Set: Valid FY2026 and FY2027. FY2026 took effect October 1, 2025.

Official Registry Overview & Definition

Nondisplaced fracture of lateral malleolus of unspecified fibula, subsequent encounter for open fracture type IIIA, IIIB, or IIIC with nonunion is a billable ICD-10-CM diagnosis code (S82.66N).

Official Tabular Instructional Notes

Sequencing, inclusion, and exclusion notes published for S82.66XN in the official ICD-10-CM tabular list.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

  • fracture of malleolus

Excludes1 — Not Coded Here

Conditions that can never be reported with this code; the two are mutually exclusive.

  • pilon fracture of distal tibia (S82.87-)
  • traumatic amputation of lower leg (S88.-)

Excludes2 — Not Included Here

Conditions not covered by this code, but which may be reported alongside it when both are present.

  • fracture of foot, except ankle (S92.-)
  • periprosthetic fracture around internal prosthetic ankle joint (M97.2)
  • periprosthetic fracture around internal prosthetic implant of knee joint (M97.1-)
  • burns and corrosions (T20-T32)
  • frostbite (T33-T34)
  • injuries of ankle and foot, except fracture of ankle and malleolus (S90-S99)
  • insect bite or sting, venomous (T63.4)

Frequently Asked Questions (FAQ) & Clinical Guidance

Does S82.66XN require a 7th character?

Yes. The appropriate 7th character is to be added to all codes from category S82.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to S82.66XN in its code family, with their registry titles.

  • S82.66XG — Nondisplaced fracture of lateral malleolus of unspecified fibula, subsequent encounter for closed fracture with delayed healing
  • S82.66XH — Nondisplaced fracture of lateral malleolus of unspecified fibula, subsequent encounter for open fracture type I or II with delayed healing
  • S82.66XJ — Nondisplaced fracture of lateral malleolus of unspecified fibula, subsequent encounter for open fracture type IIIA, IIIB, or IIIC with delayed healing
  • S82.66XK — Nondisplaced fracture of lateral malleolus of unspecified fibula, subsequent encounter for closed fracture with nonunion
  • S82.66XM — Nondisplaced fracture of lateral malleolus of unspecified fibula, subsequent encounter for open fracture type I or II with nonunion
  • S82.66XP — Nondisplaced fracture of lateral malleolus of unspecified fibula, subsequent encounter for closed fracture with malunion
  • S82.66XQ — Nondisplaced fracture of lateral malleolus of unspecified fibula, subsequent encounter for open fracture type I or II with malunion
  • S82.66XR — Nondisplaced fracture of lateral malleolus of unspecified fibula, subsequent encounter for open fracture type IIIA, IIIB, or IIIC with malunion
  • S82.66XS — Nondisplaced fracture of lateral malleolus of unspecified fibula, sequela
  • S82.8 — Other fractures of lower leg

View all codes in the S82 family