2026 ICD-10-CM Diagnosis Code M76.42Tibial collateral bursitis [Pellegrini-Stieda], left leg

ICD-10-CM Codes›M00–M99›M70-M79›M76

ICD-10-CM M76.42
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M76.42 is a billable ICD-10-CM diagnosis code for tibial collateral bursitis [Pellegrini-Stieda], left leg. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 557 through 558. Coders also document this condition as bilateral bursitis of knees. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified connective tissue disease.

Code Identity

ICD-10-CM Code
M76.42
Billable Status
Yes — Valid for Submission
Code Describes
Tibial collateral bursitis [Pellegrini-Stieda], left leg
Short Description
Tibial collateral bursitis [Pellegrini-Stieda], left leg
Same as the full description in the CMS dataset.
Parent Code
M76.4
Tibial collateral bursitis [Pellegrini-Stieda]

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM70-M79Other soft tissue disorders
CategoryM76Enthesopathies, lower limb, excluding foot
This CodeM76.42Tibial collateral bursitis [Pellegrini-Stieda], left leg

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Bilateral bursitis of knees
  • Bilateral tibial collateral ligaments bursitis
  • Inflammation of semimembranosus muscle bursa of left knee
  • Inflammation of semimembranosus muscle bursa of right knee
  • Semimembranosus bursitis

Clinical ClassificationClinical

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

CCSR MUS025
Other specified connective tissue disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Bursitis

A bursa is a small, fluid-filled sac that acts as a cushion between a bone and other moving parts, such as muscles, tendons, or skin. Bursitis occurs when a bursa becomes inflamed. People get bursitis by overusing a joint. It can also be caused by an injury. It usually occurs at the knee or elbow.

Read the full article at MedlinePlus

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

Convert M76.42 to ICD-9-CMHistory

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

ICD-9-CM
726.62 Tibial coll lig bursitis
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 M76.42Overview

Is M76.42 (Tibial collateral bursitis [Pellegrini-Stieda]) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report tibial collateral bursitis [Pellegrini-Stieda], left leg on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M76.42 group to?

When tibial collateral bursitis [Pellegrini-Stieda], left leg is the principal diagnosis on an inpatient stay, it groups to MS-DRG 557, 558, with relative weights from 0.8932 to 1.4869 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M76.42?

Under the General Equivalence Mappings, tibial collateral bursitis [Pellegrini-Stieda], left leg converts to ICD-9-CM 726.62 (tibial coll lig bursitis). 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.