M91.12 ICD-10-CM Code: Juvenile osteochondrosis of head of femur [Legg-Calvé-Perthes], left leg
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Inpatient Payment Groups (MS-DRG)
MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43.0, Appendix B.
- MS-DRG 553 — BONE DISEASES AND ARTHROPATHIES WITH MCC (MDC 08)
- MS-DRG 554 — BONE DISEASES AND ARTHROPATHIES WITHOUT MCC (MDC 08)
A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.
Official Registry Overview & Definition
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for M91.12 in the official ICD-10-CM tabular list.
Excludes1 — Not Coded Here
Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
- slipped upper femoral epiphysis (nontraumatic) (M93.0-) Compare M91.12 vs M93.0 →
- postprocedural chondropathies (M96.-) Compare M91.12 vs M96 →
Frequently Compared Codes
The official Excludes notes on M91.12 name these codes. Each comparison page covers when the two can — or must not — be reported together.
Change history
No changes recorded for this code — unchanged since the FY2016 baseline of the change ledger.
Verify Before Coding
- No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.
From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim.
Contextual Map
Every relationship of M91.12 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Hierarchy
- M00-M99 — Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) (M00-M99) [Hierarchy]
- M91-M94 — Chondropathies [Hierarchy]
Referenced by Excludes1 notes
- M87 — Osteonecrosis [Excludes1](via M91.-): “juvenile osteonecrosis (M91-M92)” · check together
Clinical classification (CCSR)
- MUS028 — Other specified bone disease and musculoskeletal deformities [CCSR]
Potential MS-DRG
- DRG 553 — BONE DISEASES AND ARTHROPATHIES WITH MCC [MS-DRG]: “BONE DISEASES AND ARTHROPATHIES WITH MCC (MDC 08)”
- DRG 554 — BONE DISEASES AND ARTHROPATHIES WITHOUT MCC [MS-DRG]: “BONE DISEASES AND ARTHROPATHIES WITHOUT MCC (MDC 08)”
MDC crossing · procedures (18508)
- MDC 08 — Diseases and Disorders of the Musculoskeletal System and Connective Tissue [MDC crossing]: “Diseases and Disorders of the Musculoskeletal System and Connective Tissue — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs.”
- 005T0ZZ — Destruction of Spinal Meninges, Open Approach [Same-MDC procedure]: “Destruction of Spinal Meninges, Open Approach — grouped in MDC 08, the procedure side of this code's crossing.” · check together
- 005T3ZZ — Destruction of Spinal Meninges, Percutaneous Approach [Same-MDC procedure]: “Destruction of Spinal Meninges, Percutaneous Approach — grouped in MDC 08, the procedure side of this code's crossing.” · check together
- 005T4ZZ — Destruction of Spinal Meninges, Percutaneous Endoscopic Approach [Same-MDC procedure]: “Destruction of Spinal Meninges, Percutaneous Endoscopic Approach — grouped in MDC 08, the procedure side of this code's crossing.” · check together
- 005W0Z3 — Destruction of Cervical Spinal Cord using Laser Interstitial Thermal Therapy, Open Approach [Same-MDC procedure]: “Destruction of Cervical Spinal Cord using Laser Interstitial Thermal Therapy, Open Approach — grouped in MDC 08, the procedure side of this code's crossing.” · check together
- 005W0ZZ — Destruction of Cervical Spinal Cord, Open Approach [Same-MDC procedure]: “Destruction of Cervical Spinal Cord, Open Approach — grouped in MDC 08, the procedure side of this code's crossing.” · check together
- and 18503 more
Nearest codes (25)
- M91 — Juvenile osteochondrosis of hip and pelvis [Sibling]
- M91.0 — Juvenile osteochondrosis of pelvis [Sibling]
- M91.1 — Juvenile osteochondrosis of head of femur [Legg-Calvé-Perthes] [Sibling]
- M91.10 — Juvenile osteochondrosis of head of femur [Legg-Calvé-Perthes], unspecified leg [Sibling]
- M91.11 — Juvenile osteochondrosis of head of femur [Legg-Calvé-Perthes], right leg [Sibling]
- M91.2 — Coxa plana [Sibling]
- M91.20 — Coxa plana, unspecified hip [Sibling]
- M91.21 — Coxa plana, right hip [Sibling]
- and 17 more
Referenced by Other Codes
Clinical classification (AHRQ CCSR):MUS028 — Other specified bone disease and musculoskeletal deformities (default).
Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.
Potential MS-DRG Relationships (FY2026)
Not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity.
Named in the grouper logic of 2 MS-DRGs: DRG 553 (MDC 08), DRG 554 (MDC 08).
From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.
Official ICD-10-CM tabular notes on other codes that name M91.12 or its code family.
1 Excludes1 notes: M87 (via M91.-).
Nearest Codes in This Family
Official ICD-10-CM classifications closest to M91.12 in its code family, with their registry titles.
- M91 — Juvenile osteochondrosis of hip and pelvis
- M91.0 — Juvenile osteochondrosis of pelvis
- M91.1 — Juvenile osteochondrosis of head of femur [Legg-Calvé-Perthes]
- M91.10 — Juvenile osteochondrosis of head of femur [Legg-Calvé-Perthes], unspecified leg
- M91.11 — Juvenile osteochondrosis of head of femur [Legg-Calvé-Perthes], right leg
- M91.2 — Coxa plana
- M91.20 — Coxa plana, unspecified hip
- M91.21 — Coxa plana, right hip
- M91.22 — Coxa plana, left hip
- M91.3 — Pseudocoxalgia