Inflammation of the bicipital tendon at the right shoulder, typically involving the long head of the biceps brachii where it runs through the bicipital groove.

Documentation tips

What should appear in the chart to support M75.21.

Source · Editorial brief grounded in 5 cited references ↓

• Explicitly state 'right shoulder' — laterality must appear in the note to justify M75.21 over M75.20.
• Record the results of provocative tests by name: Speed's test (resisted forward flexion with elbow extended) and Yergason's test (resisted supination with elbow flexed) are the key clinical validators.
• Summarize imaging findings when obtained: ultrasound tendon sheath fluid ≥3 mm, tendon echogenicity changes, or MRI signal abnormality in the biceps tendon support medical necessity.
• Document conservative care already attempted (activity modification, NSAIDs, physical therapy) before ordering advanced imaging or proceeding to injection — payors audit this sequence.
• Note functional limitations (e.g., restricted shoulder ROM, pain with overhead activity or lifting) in the history and plan to substantiate medical necessity for ongoing treatment.

Related CPT procedures

Procedure codes commonly billed with M75.21. 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 M75.21 and adjacent codes.

Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓

• Assigning M75.21 when only shoulder pain is documented — a definitive bicipital tendinitis diagnosis must be stated by the provider before using this code.
• Using M75.21 for a traumatic biceps tendon injury — acute trauma belongs in the S46 range, not the M75 family.
• Appending a shoulder pain symptom code (e.g., M79.621) alongside M75.21 after a definitive diagnosis is established — symptom codes are redundant once the condition is confirmed.
• Defaulting to M75.20 (unspecified) when laterality is clearly documented in the note — M75.21 is required whenever 'right' is specified.
• Confusing M75.21 with calcific tendinitis of the right shoulder (M75.31) — calcific tendinitis requires imaging evidence of calcium deposits and carries a distinct code.

Clinical context

Source · Editorial summary grounded in 5 cited references ↓

Sibling codes

Other billable codes under M75.2 (laterality / anatomic variants).