ICD-10-CM 2027
ICD-10 code for skull osteolysis
From the official ICD-10-CM alphabetic index entry “Osteolysis › skull”. Page updated September 29, 2026.
About coding skull osteolysis
The ICD-10-CM code for skull osteolysis is M89.58 (Osteolysis, other site).
Within M89.5, choose M89.58 (other site) only when documentation doesn't support a more specific option: unspecified site (M89.50), shoulder (M89.51), upper arm (M89.52), forearm (M89.53), hand (M89.54), thigh (M89.55), lower leg (M89.56), ankle and foot (M89.57) and 1 more.
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 564 (Other Musculoskeletal System and Connective Tissue Diagnoses with MCC, relative weight 1.4908), DRG 565 (Other Musculoskeletal System and Connective Tissue Diagnoses with CC, relative weight 0.9783) and DRG 566 (Other Musculoskeletal System and Connective Tissue Diagnoses without CC/MCC, relative weight 0.7378), in MDC 08 (Diseases and Disorders of the Musculoskeletal System and Connective Tissue), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about skull osteolysis ICD-10 codes
What is the ICD-10 code for skull osteolysis?
- M89.58 — Osteolysis, other site.
Is M89.58 billable?
- Yes. M89.58 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can M89.58 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict M89.58 as a principal diagnosis.
Is M89.58 a CC or MCC?
- No. M89.58 is neither a CC nor an MCC under MS-DRG v44.0.