Bursal inflammation that does not fit any site-specific or etiology-specific bursitis category in ICD-10-CM, and for which no anatomical location has been documented.
Verified May 8, 2026 · 4 sources ↓
- Status
- Billable
- Chapter
- 13
- Related CPT
- 6
- Region
- General
Documentation tips
What should appear in the chart to support M71.50.
Source · Editorial brief grounded in 4 cited references ↓
- Record the specific anatomical bursa by name (e.g., olecranon, trochanteric, prepatellar) — even a named site without laterality lets you move to M71.58 instead of M71.50.
- Document laterality (right or left) whenever a limb bursa is involved; it unlocks the 7th-character site codes (1=right, 2=left) and avoids the unspecified-site flag.
- Specify etiology: if the bursitis follows repetitive activity or pressure, the correct category is M70, not M71.5x — document the causative mechanism explicitly.
- Note imaging results (ultrasound fluid in bursa, MRI bursal distension) and physical exam findings (localized tenderness, fluctuance) to support medical necessity when an unspecified-site code is unavoidable.
- If the bursitis is infective, document the organism and use M71.1x series; if calcific, use M71.4x series — neither maps to M71.50.
Related CPT procedures
Procedure codes commonly billed with M71.50. 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 M71.50 and adjacent codes.
Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓
- Using M71.50 when shoulder bursitis is documented — shoulder bursitis is Excludes2 from M71.5x and must be coded to M75.5x (unspecified M75.50, right M75.51, left M75.52).
- Confusing M71.50 with M71.9x: M71.9 (bursitis NOS) applies when a site is known but no further specification is available; M71.50 is for genuinely unspecified site — and Excludes1 prevents using both simultaneously.
- Defaulting to M71.50 when an overuse or pressure mechanism is documented — that belongs in the M70 category (e.g., M70.60 trochanteric bursitis, M70.5x patellar bursitis), excluded from M71 at the category level.
- Assigning M71.50 for tibial collateral (Pellegrini-Stieda) bursitis — that is an Excludes2 condition coded to M76.4x.
- Submitting M71.50 on an injection claim (e.g., CPT 20610) without querying the provider for site; CMS coverage articles list site-specific M71.5x codes as the supported diagnoses for bursa injection coverage — M71.50 may trigger a medical necessity denial.
Clinical context
Source · Editorial summary grounded in 4 cited references ↓
M71.50 is the last-resort code for bursitis that cannot be assigned a more specific location or etiology. The M71.5x subcategory covers 'other bursitis, not elsewhere classified,' meaning the condition is neither use/overuse-driven (M70 series) nor infective, nor calcific. The unspecified-site variant (M71.50) adds a second layer of vagueness: the affected bursa is also undocumented. Before landing here, exhaust every site-specific child code — M71.52x (elbow), M71.53x (wrist), M71.54x (hand), M71.55x (hip), M71.56x (knee), M71.57x (ankle/foot), M71.58 (other named site).
Key exclusions block common misassignments. Shoulder bursitis goes to M75.5x, not M71.5x (Excludes2). Tibial collateral bursitis (Pellegrini-Stieda) goes to M76.4x (Excludes2). Bursitis NOS — when you have a site but no further specificity — goes to M71.9x, not M71.50 (Excludes1). Bursitis driven by repetitive use, overuse, or external pressure belongs to M70 (Excludes1 at the M71 category level). M71.50 also does not apply to enthesopathies (M76–M77).
In practice, M71.50 surfaces on claims when a provider documents 'bursitis' without specifying site, laterality, or etiology, and the bursitis is not a shoulder, tibial collateral, or overuse presentation. Payers increasingly flag unspecified-site codes for additional documentation, so query the provider for anatomical location before defaulting to M71.50.
Sibling codes
Other billable codes under M71.5 (laterality / anatomic variants).
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 4 cited references ↓
01When is M71.50 the correct code and not M71.9?
02Can I use M71.50 for shoulder bursitis?
03Why would a payer deny a bursa injection claim coded with M71.50?
04Does M71.50 require a 7th-character extension?
05How do I code bursitis caused by repetitive work activity at an unspecified site?
06What is the difference between M71.50 and M71.58?
07Is Pellegrini-Stieda bursitis coded to M71.50?
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/M71-/M71.50
- 03aapc.comhttps://www.aapc.com/codes/icd-10-codes/M71.50
- 04cms.govhttps://www.cms.gov/medicare-coverage-database/view/article.aspx?articleId=60304&ver=3
Mira AI Scribe
Mira AI Scribe captures the bursa name, affected side, symptom onset, provocative activity, and imaging findings (ultrasound or MRI confirming bursal fluid) from the encounter note. That detail moves the code from unspecified M71.50 to a site-specific child code, preventing medical necessity flags on injection or imaging claims and satisfying payer documentation requirements at the first submission.
See how Mira captures M71.50 documentation