2026 ICD-10-CM Diagnosis Code M86.8X8Other osteomyelitis, other site

ICD-10-CM Codes›M00–M99›M86-M90›M86

ICD-10-CM M86.8X8
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M86.8X8 is a billable ICD-10-CM diagnosis code for other osteomyelitis, other site. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 456 through 458, 539 through 541. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Osteomyelitis.

Code Identity

ICD-10-CM Code
M86.8X8
Billable Status
Yes — Valid for Submission
Code Describes
Other osteomyelitis, other site
Short Description
Other osteomyelitis, other site
Same as the full description in the CMS dataset.
Parent Code
M86.8X
Other osteomyelitis

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM86-M90Other osteopathies
CategoryM86Osteomyelitis
This CodeM86.8X8Other osteomyelitis, other site

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abscess of bone of skull
  • Abscess of cheek
  • Abscess of facial bone
  • Abscess of frontal bone
  • Abscess of nasal-orbit complex
  • Abscess of sphenoid bone
  • Abscess of temporal bone
  • Abscess of zygomatic bone
  • Acute frontal sinusitis
  • Acute osteomyelitis of knee
  • Acute osteomyelitis of patella
  • Chronic osteomyelitis of facial bone
  • Chronic sclerosing nonsuppurative osteomyelitis
  • Chronic sclerosing nonsuppurative osteomyelitis of facial bone
  • Frontal sinusitis
  • Infection of bone of pelvis and femur
  • Infection of patella
  • Inflammation of pubic symphysis
  • Osteitis of both halves of pelvis
  • Osteitis of left half of pelvis
  • Osteitis of right half of pelvis
  • Osteomyelitis of knee
  • Osteomyelitis of left pelvis
  • Osteomyelitis of right pelvis
  • Periostitis of pelvic region
  • Pott's puffy tumor
  • Sequestrum of bilateral zygomatic bones
  • Sequestrum of facial bones
  • Sequestrum of left zygomatic bone
  • Sequestrum of right zygomatic bone
  • Sequestrum of the zygomatic bone
  • Sesamoiditis
  • Suppurative osteomyelitis of jaw

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR MUS002
Osteomyelitis
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Frontal Sinusitis

    inflammation of the nasal mucosa in the frontal sinus. in many cases, it is caused by an infection of the bacteria streptococcus pneumoniae or haemophilus influenzae.

  • Chronic Frontal Sinusitis

    inflammation of the frontal sinus that typically lasts beyond eight weeks. it is caused by infections, allergies, and the presence of sinus polyps or a deviated septum. signs and symptoms include headache, nasal discharge, swelling in the face, dizziness, and breathing difficulties.

  • Frontal Sinusitis

    an acute or chronic inflammatory process affecting the mucous membrane of the frontal sinus.

Patient EducationClinical

Bone Infections

Like other parts of the body, bones can get infected. The infections are usually bacterial, but can also be fungal. They may spread to the bone from nearby skin or muscles, or from another part of the body through the bloodstream.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert M86.8X8 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
730.18 Chr osteomyelit NEC
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About M86.8X8Overview

Is M86.8X8 (Other osteomyelitis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other osteomyelitis, other site on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M86.8X8 group to?

When other osteomyelitis, other site is the principal diagnosis on an inpatient stay, it groups to MS-DRG 456, 457, 458, 539, 540, 541, with relative weights from 0.7715 to 8.4034 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M86.8X8?

Under the General Equivalence Mappings, other osteomyelitis, other site converts to ICD-9-CM 730.18 (chr osteomyelit NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.