Inflammation or calcification of the bursa adjacent to the tibial collateral (medial collateral) ligament at the right knee, consistent with Pellegrini-Stieda syndrome.
Verified May 8, 2026 · 3 sources ↓
- Status
- Billable
- Chapter
- 13
- Related CPT
- 7
- Region
- Knee
Documentation tips
What should appear in the chart to support M76.41.
Source · Editorial brief grounded in 3 cited references ↓
- Explicitly document laterality as 'right' — without it, payers may downcode to M76.40 (unspecified) on audit.
- Record imaging findings that support the diagnosis: medial knee calcification on X-ray (Pellegrini-Stieda lesion), or bursal fluid/thickening on MRI or ultrasound.
- Note whether bursitis is post-traumatic (prior MCL injury) or chronic/insidious onset — this supports the enthesopathic classification under M76 rather than M70.
- Document conservative treatment history (NSAIDs, physical therapy, aspiration) if prior authorization is required for advanced imaging or corticosteroid injection.
- If bilateral involvement exists, assign M76.41 and M76.42 separately — there is no single bilateral code in the M76.4 subcategory.
Related CPT procedures
Procedure codes commonly billed with M76.41. Linking the right diagnosis to the right procedure is what establishes medical necessity.
Source · CMS LCDs · AAOS specialty guidance · claims-pattern analysis
Common coding pitfalls
The recurring mistakes coders make with M76.41 and adjacent codes.
Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓
- Assigning M76.40 (unspecified) when the provider note clearly states 'right knee' — always capture documented laterality.
- Coding M76.41 for a plain MCL sprain or medial knee pain without documented bursitis; this code requires a confirmed bursitis or Pellegrini-Stieda diagnosis.
- Defaulting to M70 bursitis codes when the mechanism is enthesopathic rather than strictly occupational pressure — review the Excludes2 note at M76 carefully before switching categories.
- Missing a concurrent diagnosis code when calcification is the primary finding — consider whether additional coding for soft-tissue calcification is warranted based on provider documentation.
Clinical context
Source · Editorial summary grounded in 3 cited references ↓
M76.41 captures tibial collateral bursitis — also called Pellegrini-Stieda syndrome — specifically affecting the right leg. The condition involves pathologic changes (inflammation, calcification, or both) at the bursa overlying the medial collateral ligament of the right knee. It commonly follows prior medial knee trauma or chronic overuse stress to the MCL insertion and presents with medial knee pain, tenderness directly over the tibial collateral ligament, and characteristic calcification visible on plain radiograph.
Use M76.41 when the provider explicitly documents right-sided tibial collateral bursitis or Pellegrini-Stieda disease of the right knee. If laterality is not documented, fall back to M76.40 (unspecified leg). For confirmed left-leg involvement, use M76.42. Do not assign M76.41 for general medial knee pain or MCL sprain — the diagnosis requires bursitis at the tibial collateral ligament, supported by clinical exam and/or imaging.
Two important Excludes2 notes apply at the M76 category level: bursitis due to use, overuse, and pressure (M70.-) is excluded, as is enthesopathy of the ankle and foot (M77.5-). If the bursitis is attributed explicitly to occupational or pressure-related overuse rather than the enthesopathic mechanism, evaluate M70 codes instead. MS-DRG grouping lands in DRG 557 (with MCC) or DRG 558 (without MCC) under Tendonitis, Myositis and Bursitis.
Sibling codes
Other billable codes under M76.4 (laterality / anatomic variants).
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 3 cited references ↓
01What is Pellegrini-Stieda syndrome and how does it differ from standard MCL bursitis?
02Can I use M76.41 if the provider only documents 'medial knee bursitis' without naming Pellegrini-Stieda?
03Which code do I use for bilateral tibial collateral bursitis?
04When should I use M70 instead of M76.41 for knee bursitis?
05Is M76.41 valid for an outpatient injection claim?
06What DRG does M76.41 map to on inpatient claims?
07Does M76.41 require a 7th-character extension?
Sources & references
Editorial content was developed using the following public sources. Last verified May 8, 2026.
- 01CDC ICD-10-CM Tabular List 2026 (effective Oct 1, 2025)
- 02icd10data.comhttps://www.icd10data.com/ICD10CM/Codes/M00-M99/M70-M79/M76-/M76.41
- 03aapc.comhttps://www.aapc.com/codes/icd-10-codes/M76.41
Mira AI Scribe
Mira AI Scribe captures the documented side (right), the clinical finding (medial knee tenderness at the tibial collateral ligament), any imaging evidence of calcification or bursal swelling, and prior trauma or overuse history — the elements that lock in M76.41 over the unspecified M76.40 and prevent a payer downcode or specificity audit flag.
See how Mira captures M76.41 documentation