S82.436K
Nondisplaced oblique fracture of shaft of unspecified fibula, subsequent encounter for closed fracture with nonunion
S82.436K (also written S82436K) is a billable ICD-10-CM diagnosis code for nondisplaced oblique fracture of shaft of unspecified fibula, subsequent encounter for closed fracture with nonunion. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 3096 codes in category S82 (Fracture of lower leg, including ankle). Its 7th character, K, means subsequent encounter for closed fracture with nonunion. Its coding notes include a Use additional code instruction, 1 Excludes1 entry and 10 Excludes2 entries.
7th character
Category S82 requires a 7th character.
Guidelines tips
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
A fracture not stated as open or closed is coded closed, and one not stated as displaced or not displaced is coded displaced. Nonunion and malunion have their own 7th characters.
The 7th character depends on whether the patient is in active treatment, not on who sees the patient. An aftercare Z code is not used for injury aftercare.
Each injury gets its own code unless a combination code exists, with the most serious injury first. Superficial injuries at the same site as a more severe injury are not coded. Injuries during medical care are coded as complications.
Use additional code
Add the listed code as a secondary code, if known.
Also from chapter/block level (1 note)
- code to identify any retained foreign body, if applicable (Z18.-)
Excludes1
Not coded here. The listed conditions generally should not be reported together.
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (6 notes)
- birth trauma (P10-P15)
- obstetric trauma (O70-O71)
Care settings
How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.
Hospital CC
Counts as a complication or comorbidity (CC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 5,561 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.
Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix CIncludes
Further defines or gives examples of the content of the category.
- fracture of malleolus
Notes
- A fracture not indicated as displaced or nondisplaced should be coded to displaced
- A fracture not indicated as open or closed should be coded to closed
- The open fracture designations are based on the Gustilo open fracture classification
Also from chapter/block level (2 notes)
- Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
- The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.