ICD code S42.262P – Displaced lesser tuberosity fracture with malunion

Key takeaways

S42.262P is a billable ICD-10-CM code for a displaced lesser tuberosity fracture of the left humerus with malunion, at a subsequent encounter.

The 7th character P means the fracture healed in an abnormal position. A fracture that failed to unite takes K (nonunion) instead.

Laterality is a hard requirement. S42.261P is the right-side code and S42.263P is unspecified, so match the code to the documented side.

Imaging must confirm the malunion, and the record must show the patient is still receiving care for it.

Pabau, the practice management platform we build, helps billing teams validate diagnosis-to-procedure pairings before a claim is submitted.

ICD-10 code S42.262P: Definition, billable status, and quick reference

ICD-10 code S42.262P is a billable ICD-10-CM code for a displaced lesser tuberosity fracture of the left humerus, at a subsequent encounter for malunion. It is valid for the current fiscal year (FY 2027, from October 1, 2026). The code sits in Chapter 19 of the tabular list, which covers injury, poisoning and certain other consequences of external causes. Its block is S40-S49, injuries to the shoulder and upper arm.

Clinical meaning: Displaced fracture of the lesser tuberosity with malunion

The lesser tuberosity is a bony prominence on the anterior surface of the proximal humerus. It is the attachment point for the subscapularis muscle, part of the rotator cuff complex. Fractures here are less common than greater tuberosity injuries, but they matter. The subscapularis drives internal rotation and keeps the front of the shoulder stable.

A displaced fracture means the fracture fragments have separated beyond acceptable alignment and are no longer in anatomical position. Displacement matters for coding because it determines both treatment approach and the specific code within the S42.26x family (displaced vs nondisplaced).

Malunion means the fracture did heal, but in an abnormal position. The bone has united, just not in correct alignment. This is the key clinical distinction from nonunion: The fracture is no longer broken. The healed position still causes functional deficit, pain, or mechanical restriction.

Patients with lesser tuberosity malunion typically present with limited internal rotation, anterior shoulder pain with resisted motion, and subscapularis weakness on testing.

• Subscapularis involvement: Malunited lesser tuberosity fractures can impair subscapularis function even after healing, requiring physical therapy or surgical correction.
• Imaging confirmation: Malunion is diagnosed radiographically. Standard shoulder X-rays (AP and axillary views) or a CT scan confirm the healed-but-malaligned position.
• Treatment implications: Depending on functional deficit, management ranges from structured rehabilitation to corrective osteotomy or shoulder arthroplasty.
• Laterality specificity: S42.262P designates the left side, so documentation must explicitly state the left shoulder.

Breaking down S42.262P: Character-by-character structure

Each character position in S42.262P carries a distinct anatomical or encounter meaning. Understanding the structure helps coders select the correct code and confidently choose the 7th character extender.

The 6th character encodes displacement and laterality: 1 = displaced right, 2 = displaced left, 3 = displaced unspecified, 4-6 = the same three for nondisplaced. Using S42.263P when the chart clearly states “left shoulder” is a laterality specificity error that commercial payers and Medicare auditors flag routinely.

Understanding the 7th character P in ICD-10 code S42.262P

The 7th character extender for S42.262 encodes both the encounter type and the fracture’s healing status. Selecting the wrong character is a frequent denial trigger for this code family. The seven valid options are shown below.

Character P applies when imaging confirms the fracture united in malalignment and the patient is still receiving treatment or follow-up for that malunion. Once active treatment ends and only the residual effect remains, the encounter shifts to sequela (S). The ladder below puts these rules in the order a coder should check them.

S42.262P vs adjacent codes: Laterality, displacement, and healing status

The S42.26x family covers all lesser tuberosity fractures across three axes: Laterality (right/left/unspecified), displacement (displaced vs nondisplaced), and 7th character. Coders must confirm all three before selecting a code. The table below maps the most commonly confused neighbors.

Two errors come up often in this code family. One is reversing laterality, using S42.261P for the left side. The other is using unspecified S42.263P when the operative or imaging report clearly identifies the left shoulder. Payers treat unnecessary unspecified-laterality codes as incomplete documentation.

Malunion vs nonunion: Why the distinction matters for claim accuracy

Malunion and nonunion are distinct clinical diagnoses that map to different 7th characters, different treatment approaches, and different payer expectations for supporting documentation. Swapping them is an audit flag.

The American Hospital Association’s Coding Clinic for ICD-10-CM/PCS treats malunion versus nonunion as a recurring source of coder queries. Radiology language like “healed in varus/valgus” or “consolidated in malalignment” supports P (malunion). When the report reads “no evidence of fracture healing” or “fibrous union,” that supports K.

CPT codes commonly paired with S42.262P

Because S42.262P is a subsequent-encounter malunion code, the CPT codes associated with it reflect either ongoing rehabilitation or surgical correction. The pairing depends on where the patient is in their treatment course. Office follow-ups for the malunion usually bill as 99213 through 99215, depending on medical decision making.

Verify each CPT-to-ICD pairing against the payer’s medical necessity policy before submission. Malunion repair (24430 or 24435) and corrective osteotomy (24400) need imaging that documents the malunion, plus the operative report. The record should also explain why non-operative management was not enough. CPT codes are maintained by the American Medical Association, and payer coverage criteria change every year.

Documentation requirements for S42.262P

Claims submitted with S42.262P require a specific documentation set. Missing any element below is a common denial trigger, particularly for Medicare and commercial orthopedic policies. Validating diagnosis-to-procedure pairings before submission catches many of these denials before a payer sees the claim.

• Original fracture documentation: The medical record must establish that a fracture occurred, through ED notes, an initial orthopedic visit or prior imaging that confirms it.
• Laterality stated explicitly: The encounter note must identify “left shoulder” or “left humerus.” A generic “shoulder fracture” note does not support a laterality-specific code.
• Imaging confirming malunion: The 7th character P needs a radiology report (X-ray or CT) that describes bony union in malalignment, angulation, or abnormal position.
• Subsequent encounter established: The note must show this is a follow-up visit, not the initial fracture presentation. Treatment dates, prior visit references or the clinical narrative should make this clear.
• Active treatment or management: The patient must still be receiving care for the malunion. A physical therapy referral, surgical planning, pain management or a functional assessment shows this.
• Medical necessity statement: Clinical rationale for continued care must be present, particularly when surgical correction is planned or repeated visits are submitted.

Knowing what a clean claim requires helps billing staff build documentation checklists for malunion codes like this one. Those checklists stop denials before the claim is submitted.

Physical therapy visits often carry S42.262P as the supporting diagnosis, billed under 97110 or 97530. Notes that record functional status, treatment goals and progress next to the diagnosis code make the medical necessity case much stronger.

Common claim denial reasons for S42.262P and how to avoid them

Claims using S42.262P are denied for a predictable set of reasons. Most are documentation failures rather than coding errors. The right code was used, but the supporting record did not back it up. Effective denial management workflows start with knowing which documentation faults payers look for on this code family. The denial codes on the remittance advice tell you which fault the payer found.

Excludes notes and coding conventions for S42.262P

The S42 category carries coding conventions that govern what codes may or may not be reported alongside S42.262P. These come from the ICD-10-CM tabular list and the Official Guidelines for Coding and Reporting. The Centers for Medicare and Medicaid Services (CMS) and the National Center for Health Statistics (NCHS) publish both each year.

Excludes1 (cannot be coded together): S42 codes carry an Excludes1 note for traumatic amputation of the shoulder and upper arm (S48.-). If a traumatic amputation occurred, S48 takes precedence and S42 fracture codes are not reported in the same encounter.

Excludes2 (both may be coded when both are present): Periprosthetic fracture around an internal prosthetic shoulder joint (M97.3-). The same applies to physeal fractures of the upper end of the humerus (S49.0-). Report these alongside S42 when both conditions exist.

• External cause code: An external cause code (V00-Y99) can record how the injury happened, such as a fall from a ladder. These codes are optional, but they support medical necessity and workers’ compensation claims.
• Place of occurrence and activity: A place of occurrence code (Y92.-) and an activity code (Y93.-) may be added. Use them when the encounter involves the original injury context.

How Pabau helps billing teams catch S42.262P errors

The denials above come down to three checks: Laterality, the 7th character and the radiology report. In many practices, a biller runs those checks by hand after the visit, one claim at a time.

Pabau, the practice management platform we build, keeps the encounter note and the billing record in one system. Its claims management software helps billing teams validate diagnosis-to-procedure pairings before submission.

That matters most for orthopedic practices with high volumes of fracture follow-ups, where 7th character errors repeat across several visits. A pairing caught before submission never becomes a denial to appeal.

Reduce claim denials on fracture follow-up codes

Pabau’s claims management tools help orthopedic and musculoskeletal practices validate diagnosis-to-procedure pairings before each claim goes out.

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Conclusion

The 7th character P is the part of this code that is easiest to get wrong and hardest to defend in an audit. Read the radiology report before you assign it. If imaging shows no union, the code takes K. If healing is only slow, it takes G.

Then check that the note names the left side and shows care is still active. Those two lines in the chart decide whether a malunion follow-up pays the first time.

Orthopedic and musculoskeletal practices with high volumes of fracture follow-ups gain the most from checking pairings before submission. Book a demo to see how Pabau helps your billing team review fracture claims before they reach payers.

Continue your research

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Want to understand denial patterns across fracture codes? Denial codes in medical billing maps the most common CARC denial reason codes that accompany musculoskeletal claim rejections.

Coding the nondisplaced fracture at a routine follow-up? ICD-10 code S42.265D covers a nondisplaced lesser tuberosity fracture of the left humerus with routine healing.

Coding a malunion higher up the humerus? ICD-10 code S42.226P covers a nondisplaced surgical neck fracture that healed with malunion.

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