ICD-10 Code S82.022J: Displaced longitudinal fracture of left patella

Key Takeaways

S82.022J is a billable ICD-10-CM code for displaced longitudinal fracture of the left patella, subsequent encounter for open fracture type I or II with nonunion – valid for FY 2026 billing.

The 7th character J encodes three simultaneous qualifiers: subsequent encounter, open fracture Gustilo type I or II, and nonunion. All three must be confirmed in the medical record before using this code.

S82.022 (without a 7th character) is non-billable. You must append one of its child codes (A through S) to submit a claim – S82.022J is one of those billable children.

Pabau’s claims management software includes built-in ICD-10-CM catalogues and Claim.MD clearinghouse integration, so coders can validate and submit S82.022J claims without leaving the platform.

ICD-10 Code S82.022J: full description and billable status

Most patella fracture claims get rejected at the parent code level. Submit S82.022 without a 7th character and the payer sends it back – because S82.022 is non-billable. ICD-10 Code S82.022J is the specific billable child code that adds three critical qualifiers at once: this is a subsequent encounter, the original fracture was open (Gustilo type I or II), and healing has failed (nonunion). Miss any of those three details in the chart, and you are coding the wrong character.

This reference page covers the full code description, the 7th character extension table, Gustilo-Anderson classification criteria, nonunion definition, encounter-type selection guidance, documentation requirements, related codes, and an ICD-9-CM crosswalk – everything a coder or clinician needs to use ICD-10 Code S82.022J correctly for FY 2026.

Code details at a glance

The table below summarises the key metadata for S82.022J as maintained by CMS in the ICD-10-CM annual release and confirmed across the CDC/NCHS ICD-10-CM web tool.

Code hierarchy: where S82.022J sits in ICD-10-CM

Understanding where S82.022J falls within the ICD-10-CM trauma code hierarchies helps coders navigate quickly to the right child code. The classification runs from broad injury section to the specific laterality and fracture pattern.

• S00-T88 – Injury, poisoning and certain other consequences of external causes
• S80-S89 – Injuries to the knee and lower leg
• S82 – Fracture of lower leg, including ankle
• S82.0 – Fracture of patella
• S82.02 – Displaced longitudinal fracture of patella
• S82.022 – Displaced longitudinal fracture of left patella (non-billable; requires 7th character)
• S82.022J – Displaced longitudinal fracture of left patella, subsequent encounter for open fracture type I or II with nonunion (billable)

The counterpart for the right patella is S82.021J; for an unspecified side, S82.029J. The laterality distinction is not optional – the medical record must state “left” to justify S82.022J over its siblings.

Understanding the 7th character J

The 7th character in S82.022 does more than label the encounter type. It simultaneously encodes the fracture’s openness (Gustilo classification), the healing outcome (nonunion, malunion, or routine), and the care phase (initial vs subsequent). For ICD-10 Code S82.022J, all three of the following must be true: this visit is not the first encounter for active fracture care, the original fracture involved an open wound classified as Gustilo type I or II, and the fracture has not united as expected. See also: ICD-10-CM coding for subsequent encounters for a broader discussion of encounter-type assignment.

Full 7th character extension table for S82.022

The table below shows every billable child code under S82.022, per the AAPC ICD-10-CM code lookup.

What is a displaced longitudinal fracture of the patella?

The patella (kneecap) is a sesamoid bone embedded in the quadriceps tendon. A longitudinal fracture splits it along its vertical axis, running roughly parallel to the long axis of the leg. This is distinct from the more common transverse pattern (horizontal split) and from comminuted fractures (multiple fragments).

“Displaced” means the fracture fragments have moved apart – typically more than 2 mm of separation or more than 2 mm of articular step-off, per orthopedic consensus. Displacement determines surgical candidacy; nondisplaced longitudinal fractures can often be managed conservatively. Clinicians working in physical therapy practice management frequently manage the rehabilitation phase of these injuries after surgical fixation.

Longitudinal patella fractures typically result from direct trauma – dashboard injuries, falls onto the knee, or sports impacts. They are less common than transverse fractures. Patients present with anterior knee pain, swelling, and inability to perform a straight-leg raise when displacement is significant. Recovery guidance for the post-fixation phase is addressed in physical therapy protocols for fracture recovery.

Open fracture type I and type II: the Gustilo-Anderson classification

The Gustilo-Anderson classification is the standard system for grading open fractures by soft tissue injury severity. The 7th character J in S82.022J is only valid when the original fracture was Gustilo type I or type II – not type III. Misidentifying the Gustilo grade leads to the wrong 7th character and a potential audit risk.

The wound size thresholds above are approximate – Gustilo classification is a clinical determination made by the treating surgeon at the time of initial debridement, and the exact measurements may vary by clinical context. The critical distinction for coders: if the original surgical notes document “type I” or “type II” open fracture, character J applies for subsequent nonunion encounters. If they document “type III,” use M instead.

Fracture nonunion: clinical and coding implications

Nonunion means the fracture has not healed and shows no progressive signs of healing. It is a clinical determination – typically supported by serial radiographs showing absence of bridging callus – rather than a fixed time threshold. Orthopedic consensus generally considers a fracture to be in nonunion territory when healing has stalled, though the specific timeframe varies by fracture location, patient factors, and clinical context.

Nonunion is distinct from two related concepts coders sometimes confuse with it:

• Delayed union: Healing is slower than expected but still progressing. Use 7th character H (for open type I/II delayed healing) rather than J.
• Malunion: The fracture has healed, but in an incorrect position. Use 7th character P (for open type I/II malunion) rather than J.
• Nonunion: No healing progression. The fracture gap persists. Character J applies.

For S82.022J, the treating physician must document nonunion explicitly. A note that says “patient continues to have pain” or “fracture not healed” is insufficient on its own. The documentation should reference imaging findings confirming absence of union and the surgeon’s clinical conclusion that the fracture is in nonunion.

Subsequent encounter vs initial encounter: how to choose the right code

This is where most coding errors for S82.022J occur. The ICD-10-CM guidelines define encounter types based on the phase of care – not simply whether the patient has been seen before. A patient can be new to your practice and still warrant a subsequent encounter code if the active fracture treatment happened elsewhere.

For ICD-10-CM diagnosis code documentation across all fracture codes, the ICD-10-CM Official Guidelines instruct coders to use an initial encounter character (A, B, or C) “while the patient is receiving active treatment for the fracture” – including surgical treatment, ED care, and evaluation by a new physician who initiates a treatment plan. Once active treatment is complete and the patient is in aftercare or monitoring, subsequent characters apply.

The CMS ICD-10-CM Official Guidelines for Coding and Reporting govern how fracture codes are assigned. The key rules for S82.022J are:

• Default to displaced: When documentation does not specify whether a fracture is displaced or nondisplaced, code it as displaced (per ICD-10-CM guidelines). S82.022 (displaced) is the default.
• Default to closed: When documentation does not specify open or closed, code as closed. An open fracture requires explicit documentation of an open wound communicating with the fracture.
• Laterality is required: S82.022J specifies the left patella. If the medical record does not specify laterality, use S82.029J (unspecified side). Do not assume laterality.
• 7th character is mandatory: S82.022 without a 7th character is not a valid billable code. Every claim using a parent code in the S82.022 subcategory requires a 7th character extension to be submitted.
• Sequela coding: For late effects of a healed patella fracture (residual condition), use character S and code the residual condition first, followed by S82.022S.
• Multiple fractures: If both the left and right patella are fractured, code both separately. Do not use the unspecified-laterality code when both sides are documented.

Accurate application of these guidelines reduces the risk of claim denial. Practices using orthopedic claims management software with built-in ICD-10-CM catalogues can validate 7th character assignments before submission, catching errors before they reach the payer. Good denial management for fracture claims starts with accurate initial coding rather than appeals after the fact.

Documentation requirements for S82.022J

Six specific elements must appear in the medical record to support S82.022J. Each maps to a distinct component of the code’s descriptor. Missing even one creates an undercoding or overcoding risk.

• Laterality (left): The note must state “left patella.” “Patella fracture” without a side defaults to unspecified (S82.029J), not left.
• Fracture pattern (longitudinal): The imaging report or operative note must describe the fracture as longitudinal. A transverse fracture maps to a different code subcategory entirely.
• Displacement status (displaced): The surgeon or radiologist must document displacement. If not stated, ICD-10-CM defaults to displaced – but explicit documentation is cleaner for audit purposes.
• Open wound type (I or II): The original operative report must document the Gustilo classification. “Open fracture” alone is insufficient; the type determines whether J or M applies.
• Encounter type (subsequent): The note must reflect that active fracture treatment is complete. This visit is a follow-up, aftercare, or complication management encounter – not the initial treatment.
• Nonunion confirmation: The physician must document nonunion explicitly, ideally with a reference to serial imaging showing no progressive callus formation or bridging. Imaging reports alone are insufficient without physician interpretation.

Practices can streamline this documentation workflow using digital forms and structured clinical note templates that prompt providers to capture all six elements at the point of care. Submitting clean claims through electronic claim submission via Claim.MD further reduces rejection rates by running real-time eligibility and claim validation before the claim leaves the practice. Understanding the broader landscape of medical claims clearinghouse workflows helps coders anticipate where these documentation gaps typically surface.

Related and sibling codes

The table below shows the most commonly referenced sibling and related codes for S82.022J. These include same-subcategory siblings (different 7th character), laterality variants, and adjacent patella fracture subtypes. For lower extremity injury assessment tools used alongside these codes, see lower extremity injury assessment tools.

ICD-9-CM crosswalk

ICD-9-CM did not have the same granularity as ICD-10-CM for fracture laterality and healing status. The approximate equivalents below are useful for retrospective chart reviews and legacy data mapping. These are approximate crosswalks only – not exact equivalents. ICD List provides free ICD-9 to ICD-10 crosswalk tools for verification.

Note that in ICD-9-CM, nonunion required a separate additional code (733.82). ICD-10-CM incorporates the healing status directly into the 7th character, eliminating the need for a secondary code in most circumstances.

Streamline orthopedic billing from code to claim

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S82.022J is one of the more complex patella fracture codes precisely because it encodes three clinical facts at once: open fracture type, encounter phase, and healing failure. Getting any one of those wrong means the wrong 7th character and a claim that does not reflect the actual clinical picture.

Practices that systematise ICD-10-CM documentation – prompting providers to record Gustilo grade, laterality, and nonunion explicitly at the point of care – dramatically reduce rework on these claims. Pabau’s medical claims clearinghouse overview explains how Claim.MD integration validates code assignments before submission. To see how Pabau handles fracture coding workflows end to end, book a demo.

Continue your research

Need help understanding the broader ICD-10-CM trauma code structure? ICD-10-CM trauma code hierarchies walks through how injury codes are organised across the S00-T88 section.

Looking for clearinghouse options for your orthopedic claims? Claim.MD vs Office Ally comparison covers how the two most common clearinghouses differ for musculoskeletal billing workflows.

Want to reduce denials on fracture and trauma codes? Denial codes in medical billing explains the most common payer denial reasons and how to address them upstream.

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