ICD-10 Code L88: Pyoderma gangrenosum coding reference
L88 is the billable ICD-10-CM code for pyoderma gangrenosum. One Excludes1 note ...
Last Updated: August 4, 2026
Key takeaways
ICD-10 code S42.126S is a billable FY2026 code for a nondisplaced fracture of the acromial process, unspecified shoulder, sequela.
The 7th character S marks a late effect that shows up after the original fracture has finished healing.
The base code S42.126 takes one of seven 7th characters: A, B, D, G, K, P, and S.
Sequencing decides whether the claim pays. Code the residual condition first, then S42.126S as the injury behind it.
Practice management software like Pabau helps orthopedic and physical therapy practices pair sequela codes correctly before claims go out.
ICD-10 code S42.126S is a billable diagnosis code for a nondisplaced fracture of the acromial process, unspecified shoulder, sequela. The 7th character S tells the payer that the fracture has healed and the visit is about what it left behind. The code is valid for submission in FY2025 and FY2026 under the CMS ICD-10-CM code set.
Two decisions determine whether the claim is paid. The first is picking S over the other six 7th characters, which turns on the documented status of the fracture. The second is order. The residual condition is coded first, and S42.126S follows it.
What the S in S42.126S means
The 7th character is what separates this code from every other S42.126 variant. The letter S designates sequela, a condition produced as a direct late effect of an injury that has already healed. Per the ICD-10-CM Official Guidelines (Section I.C.19), a sequela code is used after the active healing phase of the original injury is complete.
Sequela differs from a subsequent encounter for ongoing healing. Those visits use 7th character D for routine healing or G for delayed healing. Sequela applies once the fracture has resolved and the patient presents with a residual condition. Chronic shoulder pain, restricted range of motion, and post-traumatic arthritis are the usual ones.
- When the fracture is still healing (routine): Use 7th character D (S42.126D)
- When healing is delayed: Use 7th character G (S42.126G)
- When healing resulted in nonunion: Use 7th character K (S42.126K)
- When healing resulted in malunion: Use 7th character P (S42.126P)
- When the fracture is fully healed and residual effects remain: Use 7th character S (S42.126S)
Sequela codes are not time-limited, so there is no minimum waiting period after the fracture resolves. The clinical status of the injury decides the character, not how many days have passed.
Where the code sits in the ICD-10-CM hierarchy
Knowing where S42.126S sits in the wider classification helps you confirm the category and spot related codes quickly. The CDC/NCHS ICD-10-CM web tool confirms this hierarchy for FY2026.
The “unspecified shoulder” designation reflects laterality the treating provider did not document. Query the provider whenever the side is missing, because S42.124 for the right shoulder or S42.125 for the left is the more specific choice. Use S42.126 and its variants only when the documentation genuinely does not name a side.
All 7th character variants for S42.126
The base code S42.126 needs a 7th character to be complete and billable. There are seven valid options, each standing for a different encounter context. Other fractures in the S42 category follow the same pattern, as S42.489P does for a malunion visit. The AAPC Codify ICD-10-CM lookup confirms the full character set for FY2026.
Clinical definition: Nondisplaced fracture of the acromial process
The acromion, or acromial process, is the bony prominence that forms the highest point of the shoulder. It projects from the spine of the scapula over the glenohumeral joint. It anchors the trapezius and deltoid muscles and forms the roof of the subacromial space.
A nondisplaced fracture means the bone has cracked but the fragments have not shifted out of position. In a displaced fracture, the bone ends move out of alignment. Nondisplaced acromial fractures follow direct trauma to the shoulder, falls onto an outstretched arm, or high-impact sports injuries. Practitioners at sports medicine practices see them regularly in contact-sport athletes.
- Anatomy: The acromion is part of the scapula, or shoulder blade, not the humerus
- Displacement: Nondisplaced means the bone fragments stay in anatomical alignment
- Laterality: S42.126 specifies “unspecified shoulder”, so use it only when the side is undocumented
- Fracture classification: Falls under S42.1 for scapula fractures, within the wider S42 category
When to use S42.126S instead of another 7th character
Choosing among the seven S42.126 variants comes down to one question. What is the clinical status of the fracture at today’s encounter? The table below maps common scenarios to the correct 7th character.
Pro Tip
Document the move from active fracture care to sequela status in the clinical note. Something like ‘fracture healed per imaging, patient now presents with residual shoulder stiffness from the prior acromial fracture’ does the job. That one line gives the coder what they need to justify S42.126S without a provider query.
Coding guidelines for sequela claims
The ICD-10-CM Official Guidelines set out how a sequela code pairs with the condition it caused. That rule covers every injury code, S42.126S included. Payers review sequela claims closely, and the wrong order is a common audit finding.
Sequencing rule
Code the residual condition first, then S42.126S. Section I.B.10 of the Official Guidelines puts the nature of the sequela ahead of the injury code that produced it. Post-traumatic osteoarthritis of the shoulder is reported as M19.119, followed by S42.126S. Shoulder pain follows the same pattern, with M25.519 in first position.
Two details trip coders up here. Use M19.111 or M19.112 and M25.511 or M25.512 whenever the provider documents the side. And the 7th character S attaches only to the injury code, never to the manifestation code beside it.
Documentation requirements
Three documentation elements support a clean S42.126S claim:
- A record of the original acromial fracture, such as prior imaging, an earlier encounter note, or provider attestation
- A statement that the fracture itself has resolved
- A description of the current residual condition, tied causally to that fracture
Structured patient records that keep historical injury notes in one place make that retrieval quick during billing or an audit review.
Practices using claims management software can build pairing rules that flag S42.126S when it arrives without a manifestation code. That catches the most common sequela error before the claim ever leaves the practice.
S42.126S in practice: Common clinical scenarios
Sequela encounters for acromial fractures turn up across several specialties. Once the acute fracture has resolved, patients come back weeks, months, or years later with shoulder complaints that trace to the original injury.
At physical therapy practices, S42.126S appears when a patient is referred for shoulder rehabilitation after imaging confirms the fracture healed. Treatment then targets the residual impairment, such as lost range of motion or shoulder weakness. Strength testing such as the full can test often supplies the objective finding that supports the claim.
In orthopedic outpatient settings, the code applies when a patient presents with subacromial pain or limited abduction. The provider then links that symptom to a documented prior acromial fracture.
- Physical therapy: Shoulder rehab after confirmed healing, targeting a residual range-of-motion deficit
- Orthopedics: Chronic subacromial impingement or pain attributed to a healed acromial fracture
- Primary care: Ongoing shoulder complaints where prior imaging already confirmed the fracture healed
- Sports medicine: Return-to-play evaluation showing residual shoulder weakness after an acromial fracture
Related ICD-10 codes for shoulder and scapula fractures
Coders working with S42.126S run into these neighbors regularly. Use the table as a differential reference when you are confirming that S42.126S is the most accurate choice. Other bones in the same girdle carry their own sequela and follow-up codes, including S42.032S and S42.212D.
How Pabau keeps sequela claims clean
A sequencing mistake often surfaces only when the denial lands. A biller works the rejection, re-reads the note, re-orders the codes, and resubmits weeks after the visit. The patient’s original fracture record often sits in another system, or in a paper file nobody wants to dig through.
Practice management software like Pabau moves that check to the moment of coding. Claim rules can flag S42.126S when no manifestation code sits alongside it. The patient’s earlier fracture notes and imaging stay attached to the same record, so your coder can confirm the injury resolved without leaving the chart.
The compliance tools keep that history in order for an audit two years later. For orthopedic, physical therapy, and sports medicine teams, the outcome is fewer reworked claims and faster payment on the ones they submit.
Reduce claim errors on fracture sequela codes
Pabau's claims tools help orthopedic, physical therapy, and sports medicine practices pair sequela codes correctly. Structured documentation workflows keep the fracture history that supports each claim.
Conclusion
S42.126S is a simple code with one demanding requirement. The note has to show that the acromial fracture healed and that today’s complaint traces back to it.
Two mistakes account for most denials on this code. The first is reaching for A or D when the fracture has already resolved. The second is placing S42.126S ahead of the residual condition it caused, which reverses the order the guidelines set.
Fix the documentation habit and the coding follows on its own. Book a demo to see how Pabau helps musculoskeletal practices submit sequela claims that hold up at audit.
Continue your research
Billing the sling that came with the original fracture? A4566 covers the shoulder immobilizer supply and the documentation payers expect with it.
Residual shoulder pain with no fracture in the history? M66.9 handles spontaneous tendon rupture, a common alternative explanation for the same symptoms.
Wondering why a fracture took so long to unite? M83.5 covers drug-induced osteomalacia in adults, one of the metabolic reasons bone healing stalls.
Need a note format that shows the causal link clearly? DAR notes give you a structure that ties each finding to the action taken and the response recorded.
Open wound at the shoulder rather than a fracture? S41.021A covers a laceration with a foreign body, coded by encounter rather than by sequela.
Frequently asked questions
What is ICD-10 code S42.126S?
ICD-10 code S42.126S is a billable ICD-10-CM diagnosis code for a nondisplaced fracture of the acromial process, unspecified shoulder, sequela. The 7th character S designates a late effect that appears after the active healing phase of the original fracture is complete.
What does the S in ICD-10 code S42.126S mean?
The S is the 7th character designating sequela under the ICD-10-CM Official Guidelines (Section I.C.19). It shows that the fracture itself has fully healed. The patient is now being seen for a residual condition caused by that prior injury, such as chronic shoulder pain or restricted range of motion.
When should sequela codes be used in ICD-10-CM?
Use a sequela code once the active phase of healing is complete and the patient presents with a late effect of the original injury. There is no minimum time requirement. The clinical determination that the fracture has healed is what triggers sequela code selection, not elapsed time.
Which code is sequenced first with S42.126S?
The residual condition is sequenced first, and S42.126S follows it. Section I.B.10 of the ICD-10-CM Official Guidelines puts the nature of the sequela ahead of the injury code that caused it. Shoulder pain from a healed acromial fracture is reported as M25.519, then S42.126S.
What is the difference between S42.126A and S42.126S?
S42.126A is the initial encounter code, used when the patient first receives active treatment for the fracture. S42.126S is the sequela code, used after the fracture has healed and a residual late effect remains. Using S42.126A for a healed fracture is a coding error that can trigger a denial.
Is S42.126S a billable ICD-10 code?
Yes. S42.126S is a valid, billable, HIPAA-covered ICD-10-CM code for FY2026, effective October 1, 2025. Both the CMS ICD-10-CM Tabular List and the CDC/NCHS ICD-10-CM web tool confirm it.
How does S42.126S differ from S42.126K and S42.126P?
S42.126K for nonunion and S42.126P for malunion both describe fractures that did not heal correctly. Both are still active clinical problems that need treatment. S42.126S describes a fracture that has fully healed, where the patient presents only for the residual effects of the prior injury.
