M88.859 Osteitis deformans of unspecified thigh

Billable ICD-10-CM code, FY2026.

Applies from M88 Osteitis deformans [Paget's disease of bone]

Excludes1 (never code together)

• osteitis deformans in neoplastic disease (M90.6)

MS-DRG index

Defines the logic of DRG(s) 553-554 in MDC 08.

Approximate ICD-9-CM (GEMs)

• 731.0 Osteitis deformans without mention of bone tumor (approximate)

Code annotations containing back-references to M88.859

Back-references to M88

• Type 1 Excludes: M43 Other deforming dorsopathies ("spinal curvature in Paget's disease of bone [osteitis deformans] (M88.-)")
• Type 1 Excludes: M90.6 Osteitis deformans in neoplastic diseases ("osteitis deformans [Paget's disease of bone] (M88.-)")

Nearby codes

• M88.842 Osteitis deformans of left hand
• M88.849 Osteitis deformans of unspecified hand
• M88.85 Osteitis deformans of thigh
• M88.851 Osteitis deformans of right thigh
• M88.852 Osteitis deformans of left thigh
• M88.859 Osteitis deformans of unspecified thigh (this code)
• M88.86 Osteitis deformans of lower leg
• M88.861 Osteitis deformans of right lower leg
• M88.862 Osteitis deformans of left lower leg
• M88.869 Osteitis deformans of unspecified lower leg
• M88.87 Osteitis deformans of ankle and foot