ICD-10-CM · Hip

M91.92

M91.92 identifies juvenile osteochondrosis affecting the hip and pelvis on the left side, where the specific subtype of osteochondrosis has not been documented or cannot be determined from the clinical record.

Verified May 8, 2026 · 6 sources ↓

Status: Billable
Chapter: 13
Related CPT: 10
Region: Hip

Drawn from CDCICD10DataAAPCAAOS

Documentation tips

What should appear in the chart to support M91.92.

Source · Editorial brief grounded in 6 cited references ↓

Document laterality explicitly as 'left' in the clinical note — 'left hip' or 'left leg' is required to support M91.92 over the unspecified-leg code M91.90.
Record the basis for the 'unspecified' subtype: note that imaging or workup is pending, inconclusive, or that the specific osteochondrosis variant has not yet been determined.
If X-ray, MRI, or bone scan results are available, document specific findings (e.g., femoral head flattening, subchondral collapse, epiphyseal irregularity) — these findings typically support a more specific code such as M91.12 (Legg-Calvé-Perthes, left).
Record patient age at onset; juvenile osteochondrosis is a condition of skeletally immature patients, and age documentation anchors the diagnosis within the M91 category versus adult-onset pathology.
Note the absence of trauma or nontraumatic slippage language — if SUFE is suspected, that requires M93.0- and cannot be coded alongside M91.92 per the Excludes1 rule.
If chondrolysis is also present, document it explicitly so that M94.3 can be added as an additional code per category-level instructions.

Related CPT procedures

Procedure codes commonly billed with M91.92. Linking the right diagnosis to the right procedure is what establishes medical necessity.

Source · CMS LCDs · AAOS specialty guidance · claims-pattern analysis

73521 $41.75

Bilateral hip X-ray examination capturing two radiographic views of both hips, including the pelvis when performed.

73523 $61.46

Radiologic examination of both hips, including the pelvis when performed, requiring a minimum of five views captured from multiple projections.

73525 $133.27

Radiologic examination of the hip joint using contrast material, including radiological supervision and interpretation

27035 $1,035.43

Surgical denervation of the hip joint by cutting or ablating the intra-articular nerve branches of the sciatic, femoral, or obturator nerves, performed via an intrapelvic or extrapelvic approach to reduce arthritic hip pain.

27036 $942.91

Open hip capsulectomy or capsulotomy, with or without heterotopic bone excision and release of hip flexor muscles including gluteus medius, gluteus minimus, and iliopsoas.

27130 $1,162.02

Primary total hip arthroplasty replacing both the acetabular socket and proximal femoral components with prosthetic implants, with or without bone graft.

27132 $1,504.04

Conversion of a previously operated hip — any prior surgery except total hip arthroplasty — to a complete total hip arthroplasty, replacing both femoral and acetabular components, with or without bone graft.

73502 $48.77

Radiologic exam of a single hip, capturing two or three views, including the pelvis when performed.

73503 $62.79

Radiologic examination of a single hip, including the pelvis when performed, capturing a minimum of four views from different angles.

27299 View procedure details

Common coding pitfalls

The recurring mistakes coders make with M91.92 and adjacent codes.

Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓

Coding M91.92 when a specific subtype is documented: if the note or radiology report names Legg-Calvé-Perthes, coxa plana, pseudocoxalgia, or coxa magna on the left, use the corresponding specific code (M91.12, M91.22, M91.32, or M91.42) — M91.92 is only for genuinely unspecified presentations.
Pairing M91.92 with M93.0- (slipped upper femoral epiphysis): the Excludes1 note at M91 prohibits this combination — SUFE is coded under M93.0- exclusively.
Using parent code M91.9 for billing: M91.9 is non-billable. Always code to the laterality level — M91.92 for left, M91.91 for right, M91.90 for unspecified.
Defaulting to M91.90 (unspecified leg) when the provider has clearly documented the left side: laterality is required when documented, and using the unspecified-leg code when left is known will trigger specificity downcoding and potential audit flags.

Clinical context

Source · Editorial summary grounded in 6 cited references ↓

M91.92 applies when a pediatric or adolescent patient presents with osteochondrosis of the left hip or pelvis and the chart does not support a more specific subcategory — such as Legg-Calvé-Perthes disease (M91.12), coxa plana (M91.22), pseudocoxalgia (M91.32), or coxa magna (M91.42). The 'unspecified' designation reflects a documentation gap, not a clinical one. If imaging or clinical workup has identified the exact pathology, use the appropriate specific code.

This code sits under parent M91.9 (non-billable) and is the left-leg laterality variant. M91.91 is right leg; M91.90 is unspecified leg — use M91.90 only when laterality is genuinely unknown or undocumented, which should be rare after any imaging workup. The Excludes1 note at the M91 category level prohibits simultaneous use with M93.0- (slipped upper femoral epiphysis, nontraumatic); SUFE is coded separately and never paired with M91 codes.

M91.92 is appropriate during active diagnostic workup when the clinical picture is consistent with hip/pelvis osteochondrosis on the left but the treating provider has not yet differentiated the specific type. Once the subtype is established, update the code to the most specific option available. Use with additional codes if chondrolysis is present (M94.3 per the category-level annotation).

Sibling codes

Other billable codes under M91.9 (laterality / anatomic variants).

M91.91

Juvenile osteochondrosis of hip and pelvis, unsp, right leg

M91.90

Juvenile osteochondrosis of hip and pelvis, unsp, unsp leg

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01When should I use M91.92 instead of M91.12 (Legg-Calvé-Perthes, left leg)?

Use M91.92 only when the provider has not identified the specific subtype of osteochondrosis. If the note or radiology report explicitly names Legg-Calvé-Perthes disease, M91.12 is the correct code. M91.92 is a fallback for genuinely uncharacterized cases.

02Can M91.92 and M93.0- be coded together for the same patient?

No. The Excludes1 note at the M91 category level prohibits coding M91 codes alongside M93.0- (slipped upper femoral epiphysis, nontraumatic). If SUFE is the diagnosis, use M93.0- only.

03Is M91.92 valid for adult patients?

The M91 category is designated for juvenile osteochondrosis, meaning skeletally immature patients. If the condition arises or is diagnosed in adulthood after skeletal maturity, review whether a different code category is more appropriate and ensure the clinical documentation supports the juvenile classification.

04What additional code should be reported if chondrolysis accompanies this diagnosis?

Report M94.3 as an additional code when chondrolysis is documented alongside M91.92, per the annotation instructions at the M91 category level in the ICD-10-CM Tabular List.

05Why is M91.9 not billable when M91.92 is?

M91.9 is a non-billable header code that requires further specification to the laterality level. M91.92 (left leg), M91.91 (right leg), and M91.90 (unspecified leg) are the billable child codes. Submitting M91.9 will result in claim rejection.

06Should I update M91.92 to a more specific code once workup is complete?

Yes. M91.92 is appropriate during the diagnostic workup phase when the subtype is not yet established. Once imaging confirms a specific diagnosis such as Legg-Calvé-Perthes or coxa plana, update to the corresponding specific code for all subsequent encounters.

07What is the difference between M91.92 and M91.90?

M91.90 is for cases where the affected leg is unspecified or unknown — use it only when laterality is genuinely undocumented. M91.92 is specifically for confirmed left-side involvement. When the provider documents 'left,' M91.92 is required.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira AI Scribe

Mira AI Scribe captures the affected side (left hip/leg), patient age, and imaging findings or pending workup status from the encounter note to support M91.92. It also flags whether a specific osteochondrosis subtype — Legg-Calvé-Perthes, coxa plana, pseudocoxalgia, or coxa magna — is named anywhere in the note, which would route the code to a more specific M91 subcategory and prevent an unspecified-code audit flag.

See how Mira captures M91.92 documentation