M76.61 identifies inflammatory or degenerative pathology of the Achilles tendon localized to the right leg, classified under lower-limb enthesopathies (M76). Per the ICD-10-CM Tabular List, Achilles bursitis of the right side maps here as well.

Documentation tips

What should appear in the chart to support M76.61.

Source · Editorial brief grounded in 4 cited references ↓

• Explicitly state 'right' Achilles tendinitis or tendinopathy — laterality is required to use M76.61 instead of the unspecified M76.60.
• Note whether the presentation is insertional (at the calcaneal attachment) or non-insertional (midsubstance); ICD-10-CM does not yet split these, but the detail supports medical necessity and surgical planning.
• Record symptom duration and any prior conservative care (physical therapy, orthotics, NSAIDs, prior injections) to establish medical necessity for injections, imaging, or surgery.
• If Achilles bursitis co-exists with tendinitis at the same right-side location, a single M76.61 code covers both per the Tabular 'Applicable To' note — do not add a separate bursitis code.
• For injection encounters, document the specific tendon or peritendinous target, the agent injected, and the functional deficit driving the procedure to satisfy CMS A57201 medical necessity requirements.

Related CPT procedures

Procedure codes commonly billed with M76.61. 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 M76.61 and adjacent codes.

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

• Defaulting to M76.60 (unspecified leg) when the note clearly states 'right' — always assign the laterality-specific code when documented.
• Coding M76.61 alongside a separate right Achilles bursitis code: the Tabular 'Applicable To' note under M76.6 includes Achilles bursitis, so M76.61 already covers it for the right side.
• Confusing Achilles tendinitis with Achilles tendon rupture — acute rupture maps to S86.01- (with 7th-character extension) and spontaneous rupture to M66.361; M76.61 is for tendinitis/tendinopathy, not structural tear.
• Applying M76.61 to foot-level enthesopathy — the Type 2 Excludes note under M76 redirects enthesopathies of the ankle and foot to M77.5-, so verify the anatomical site before coding.
• Reporting a symptom code (e.g., M25.571 pain in right ankle) as an additional code once M76.61 is established — the tendinitis diagnosis subsumes the pain; add symptom codes only when they describe a distinctly separate condition.

Clinical context

Source · Editorial summary grounded in 4 cited references ↓

Sibling codes

Other billable codes under M76.6 (laterality / anatomic variants).