ICD code S82.136K – Nondisplaced fracture of medial condyle of unspecified tibia

Key takeaways

ICD-10 code S82.136K reports a nondisplaced medial condyle tibia fracture at a subsequent encounter, once the closed fracture has developed nonunion.

Closed nonunion sits on the 7th character K, not J. J belongs to an open fracture of type IIIA, IIIB or IIIC with delayed healing.

S82.136 accepts sixteen valid 7th characters, so the note has to settle encounter type, skin integrity and healing status separately.

The sixth digit is the unspecified-tibia option. Query the provider for right or left, then report S82.134K or S82.135K instead.

Practice management software like Pabau validates ICD-10-CM codes before submission, so subsequent-encounter fracture claims leave the practice clean.

ICD-10 code S82.136K: code details at a glance

S82.136K is a billable, specific ICD-10-CM diagnosis code. It goes on claims to Medicare, Medicaid and commercial payers. The diagnosis it reports is a closed, nondisplaced fracture of the medial condyle of the tibia, seen at a subsequent encounter with nonunion. Verify the code year in the CDC/NCHS ICD-10-CM web tool before you submit, because the set changes every October 1.

What does ICD-10 code S82.136K mean? Breaking down the code

Every character in S82.136K carries a specific clinical meaning. Misread any one of them and the claim goes back. Here is how the string breaks down, left to right.

• S: Injury chapter (Chapter 19, ICD-10-CM). Codes starting with S cover injuries to specific body regions.
• 82: Fracture of lower leg, including ankle. This is the three-character category for tibial and fibular fractures.
• .1: Fracture of upper end of tibia. The proximal tibia subcategory, which is where the medial condyle sits.
• .13: Fracture of medial condyle of tibia, narrowing to the inner side of the knee joint.
• 6: Nondisplaced, unspecified tibia. The sixth digit carries displacement and side at once, and this value records no side.
• K: Subsequent encounter for closed fracture with nonunion. The 7th character names the visit and the healing status.

“Nondisplaced” means the fracture line is there but the bone ends have stayed in normal anatomical alignment. A displaced fracture is the opposite, with fragments moved out of position. Displacement is the difference between S82.133 and S82.136.

“Closed fracture” means the skin over the fracture site is intact, with no wound communicating with the bone. Both facts have to appear in the provider’s note to support this code.

Understanding the 7th character K in ICD-10 fracture codes

The 7th character is the most consequential decision on S82.136. Under the CMS ICD-10-CM coding guidelines, it has to record three facts at once. Those are the encounter type, whether the fracture was open or closed, and the healing status.

S82.13x takes the full open-fracture extension set, so sixteen valid 7th characters exist here, not the six that closed-only codes use. The table below runs all sixteen, with the documentation each one assumes.

The set skips I, L and O on purpose, because those letters read too easily as digits on a claim line. That is why nonunion lands on K and malunion on P, rather than on the letters that would follow J alphabetically.

K is not J. This is the single most common mix-up on this code family. J and K sit next to each other in the extension set, and both describe a subsequent encounter, so they look interchangeable. They are not.

J requires an open fracture of type IIIA, IIIB or IIIC, and it requires delayed healing rather than nonunion. Use it on a closed nonunion and you have described a high-grade open wound that the chart never documented. Payers read that as an unsupported diagnosis.

The grid below plots all sixteen characters on the two axes that decide them. It shows how far apart J and K actually sit.

K is not G either. Delayed healing means the biology is still working, just behind schedule. Nonunion means the process has effectively stopped, usually confirmed at six months or more with no bridging callus on imaging. Reaching for G when the films and the note say nonunion is the other habitual error.

Code hierarchy: Where S82.136K fits in ICD-10-CM

Reading the parent structure is the quickest way to confirm you are at the right level of specificity. S82.136K sits at the bottom of a seven-level hierarchy, and each level narrows the clinical picture further. The full tabular list is available through ICD List’s free ICD-10-CM lookup.

• S00-T88 – Injury, Poisoning and Certain Other Consequences of External Causes (Chapter 19)
• S80-S89 – Injuries to the knee and lower leg
• S82 – Fracture of lower leg, including ankle
• S82.1 – Fracture of upper end of tibia
• S82.13 – Fracture of medial condyle of tibia
• S82.136 – Nondisplaced fracture of medial condyle of unspecified tibia (no 7th character, so not billable at this level)
• S82.136K – Nondisplaced fracture of medial condyle of unspecified tibia, subsequent encounter for closed fracture with nonunion (billable)

S82.136 on its own is not a valid billable code. The 7th character is mandatory everywhere in the S82.13 family, and a claim submitted with only six characters is rejected automatically.

One level up, the S82.1 subcategory holds the other proximal tibia patterns. S82.11x covers the tibial spine, S82.12x the lateral condyle and S82.14x a bicondylar break. Only a fracture confined to the medial condyle belongs in S82.13x.

Clinical overview: Nondisplaced medial condyle tibial fracture with nonunion

The medial condyle is the inner prominence of the proximal tibia, and it forms the medial compartment of the knee joint. Fractures here usually follow valgus stress combined with axial loading. Falls, motor vehicle collisions and sports injuries are the common mechanisms.

Orthopedic and physical therapy practices carry most of the recovery phase for this injury, which is where the subsequent-encounter codes get used.

A nondisplaced medial condyle fracture is often managed without surgery, using immobilization and protected weight-bearing. Nonunion still complicates roughly 5-10% of long-bone fractures. Patient factors include osteoporosis, smoking, diabetes and poor vascular supply, and mechanical factors include premature weight-bearing and inadequate immobilization.

Once the provider declares nonunion on imaging, the 7th character moves from D or G across to the K value. Those subsequent encounters often involve bone grafting, revision of internal fixation or electrical bone stimulation. Each of those services leans on the diagnosis code for its medical necessity.

Approximate synonyms and alternate descriptions for S82.136K

The wording below turns up in provider notes and all of it maps to ICD-10 code S82.136K. Coders should read every one of these variants as the same diagnosis.

• Nondisplaced fracture of medial condyle of tibia, subsequent encounter, closed, nonunion
• Non-displaced tibial medial condyle fracture with failed fracture union, follow-up visit
• Medial condyle tibia fracture, closed, nondisplaced, nonunion, subsequent care
• Subsequent encounter for nondisplaced medial tibial condyle fracture, nonunion
• Nondisplaced fracture of inner tibial condyle, follow-up, nonunion
• Closed tibial medial condyle fracture with failed healing, follow-up encounter

Documentation requirements for accurate S82.136K coding

The provider’s note has to carry five clinical facts for S82.136K to hold up at audit. Miss one and the coder is left with a less specific code or a query.

• Fracture site: “Medial condyle of the tibia.” The note has to name this location, not just “proximal tibia” or “knee fracture.”
• Displacement status: “Nondisplaced.” The provider has to state that the fragments stayed in anatomical alignment, since an unstated status sends the code to the displaced series.
• Open vs. closed: “Closed fracture.” The skin over the fracture is intact. Section I.C.19.c defaults an undesignated fracture to closed, but an explicit statement is what keeps K defensible.
• Encounter type: “Subsequent encounter.” Active treatment has ended and this visit is follow-up, rehabilitation or complication care.
• Healing status: “Nonunion.” Imaging, usually X-ray or CT, has to show failed union, and the note should say “nonunion confirmed” or the equivalent.

Coder tip: if the imaging report mentions nonunion but the provider’s note does not, query the provider first. The ICD-10-CM Official Guidelines require the diagnosis to be stated by the treating provider, not inferred by the coder from diagnostic findings.

Laterality is the sixth item worth chasing. S82.136 is the unspecified-tibia option, and the guidelines reserve unspecified codes for records that genuinely do not name a side. Ask the provider, then report S82.134K for the right tibia or S82.135K for the left.

Coding guidelines: When to use S82.136K vs related codes

Picking the wrong 7th character is the most common error on this family. The table below runs the five subsequent-encounter scenarios that come up most often for S82.136, with the correct code and the decision point behind it.

One pitfall shows up in audits again and again. A coder selects S82.136G when the imaging clearly shows nonunion, because “delayed healing” feels like the safer, less severe description.

That choice invites a medical necessity denial. Payers expect K when the provider documents nonunion and the practice bills bone stimulation or surgical revision alongside it.

Review the denial codes in billing to see which rejection messages a payer sends when the diagnosis does not support the service billed.

Related ICD-10-CM codes for medial condyle tibial fractures

S82.136K belongs to a family that varies by displacement, laterality and encounter type. The table below covers the siblings that come up most in orthopedic charts. Use the AAPC Codify ICD-10-CM lookup to confirm current descriptions for any code in this family.

Note the pattern in the sixth digit. S82.134 and S82.135 name the right and left tibia for a nondisplaced medial condyle fracture, and S82.136 is the unspecified option. Query for the side whenever the chart allows it, because unspecified codes attract payer scrutiny.

Billing and reimbursement notes for S82.136K

S82.136K is accepted for claim submission under ICD-10-CM. Whether the claim pays depends on the payer’s policy, the medical necessity documentation and the services billed with it. A valid diagnosis code does not guarantee payment. It establishes the condition that the procedure codes have to be necessary for.

For orthopedic practices submitting electronically, practice management software like Pabau sends claims through the Claim.MD clearinghouse, which covers thousands of US payers. That connection supports CMS-1500 and 837P submission with built-in ICD-10 code validation.

Practices using claims management software catch errors such as a missing 7th character or unspecified laterality before the claim leaves the building.

• Medicare: Nonunion subsequent-encounter codes are recognized for reimbursement when the claim documents medical necessity for the billed service. That covers an office visit, a bone stimulator, surgical revision or therapy.
• Prior authorization: Surgical treatment for nonunion, such as bone grafting or revision ORIF, usually needs prior authorization from commercial payers. Submit S82.136K as the supporting diagnosis on the request.
• Denial risk: Pairing S82.136K with a procedure tied to initial fracture care, such as a new reduction, will draw a query. Match the procedure code to a subsequent nonunion encounter.
• External cause code: A code from the V00-Y99 range should accompany S82.136K to record how the fracture happened. The fracture code is sequenced first and the external cause code follows.
• Code validity: S82.136K is valid for FY2026, covering October 1, 2025 through September 30, 2026. Check the current CMS release before submitting in a new fiscal year.

How Pabau keeps nonunion fracture claims clean

In most practices the 7th character is decided twice. The provider describes the healing status in the note, and days later a biller reads that note and picks a letter. Anything the note left vague gets settled by whoever is closest to the deadline.

Practice management software like Pabau closes that distance. Fracture follow-ups run on structured medical forms. Displacement, skin integrity, laterality and healing status are captured as fields at the visit, rather than reconstructed later. The coder then reads a record that already answers all four questions K depends on.

Claims then go out through the Claim.MD integration, with ICD-10 validation on the way. A six-character stub or an unspecified-laterality code gets caught before submission. Reporting shows which codes get denied and why, which is how you spot a run of S82.136G claims that should have been S82.136K.

The result is a shorter revenue cycle on exactly the encounters that carry the most documentation risk. Every Pabau subscription includes the full feature set, so clinical forms, coding validation and denial reporting arrive together.

Streamline fracture coding and claim submission

Pabau connects ICD-10-CM coding workflows to electronic claim submission through Claim.MD, covering thousands of US payers. See how orthopedic and physical therapy practices cut denials on subsequent-encounter codes.

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Conclusion

S82.136K asks three questions of the chart at once. The visit has to be a subsequent encounter, the fracture has to be closed, and the provider has to have declared nonunion. Get one wrong and you have either the wrong code or a query to write.

The letter next door is the one to watch. J describes an open type IIIA, IIIB or IIIC fracture with delayed healing, which is a different injury and a different healing status. Sixteen characters share this base code, and only K carries closed nonunion.

Pabau’s revenue cycle tools and the Claim.MD integration validate ICD-10-CM codes before submission. Orthopedic and physical therapy practices use them to track denials tied to subsequent-encounter coding. To see how that works on your own fracture caseload, book a demo.

Continue your research

Managing fracture billing denials? Denial management in healthcare covers the most common payer rejection patterns for orthopedic and injury codes.

Need to understand the claims submission process? Medical claims clearinghouse explains how 837P electronic claims flow from practice to payer and where errors are caught.

Coding the same fracture at a later stage? ICD-10 code S82.136S covers the sequela character for this base code, once treatment moves to a late effect.

New to the revenue cycle side of coding? What is medical billing walks a claim from encounter to payment, so you can see where the 7th character decides the outcome.

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