ICD-10 Code M25.572: Pain in Left Ankle and Joints of Left Foot

Key Takeaways

M25.572 is a billable ICD-10-CM code for pain in the left ankle and joints of the left foot, valid from FY2016 through FY2026.

Use M25.572 for symptom-stage documentation before a definitive diagnosis is established – not when a more specific condition (e.g. plantar fasciitis M72.2 or ankle sprain S93.4) has been confirmed.

Excludes2 notes prohibit using M25.572 alongside codes for pain in the limb (M79.6-), foot and toes (M79.67-), or fingers (M79.64-) – verify exclusions before submitting claims.

Pabau’s claims management software helps physical therapy, podiatry, and orthopedic practices flag Excludes2 conflicts and reduce left ankle pain claim denials before submission.

Left ankle pain accounts for millions of outpatient visits each year, yet claim denials for this diagnosis are surprisingly common. The problem is usually not the code itself – M25.572 is straightforward. The problems arise from misapplying it when a more specific diagnosis is available, or from ignoring the Excludes2 interactions that quietly invalidate claims on submission. Under CMS ICD-10-CM guidelines, coders and clinicians are responsible for selecting the most specific code supported by documentation. This guide covers ICD-10 Code M25.572 in full: its clinical scope, correct usage criteria, related codes, exclusions, documentation requirements, and billing workflow tips for the specialties that use it most.

Physical therapists, podiatrists, sports medicine physicians, and orthopedic coders all encounter this code regularly. Whether you are verifying billability for a new patient evaluation or reconciling a denial, the sections below give you what you need without the filler.

ICD-10 Code M25.572: Clinical Description and Code Structure

ICD-10 Code M25.572 describes pain localized to the left ankle joint and the joints of the left foot. It sits within the ICD-10-CM Chapter 13 (Diseases of the musculoskeletal system and connective tissue, M00-M99), under the subsection M20-M25 (Other joint disorders), parent code M25.5 (Pain in joint). The CDC/NCHS ICD-10-CM lookup tool confirms this code has been valid and billable every fiscal year from FY2016 through FY2026 without interruption.

The code covers pain at the talocrural joint (the main ankle articulation between the tibia and the talus), the subtalar joint, and the smaller joints of the left foot. Importantly, the description includes joints of the left foot alongside the ankle itself – so pain that spreads from the ankle into the midfoot joints can be captured under this single code, provided no more specific diagnosis has been established.

Code Hierarchy at a Glance

This laterality-specific code was introduced with the October 1, 2015 ICD-10 implementation mandate. Its ICD-9-CM predecessor was 719.47 (Pain in joint, ankle and foot), though that crosswalk is approximate – the ICD-10 version adds left-side specificity that ICD-9 did not capture. Refer to ICD-10 code specificity guidelines for context on how laterality requirements affect coding across Chapter 13.

When to Use ICD-10 Code M25.572

M25.572 is a symptom code. Use it when a patient presents with left ankle or left foot joint pain and no definitive underlying condition has been diagnosed or documented. According to standard ICD-10-CM Official Guidelines for Coding and Reporting (published by the Centers for Medicare and Medicaid Services and the National Center for Health Statistics), signs and symptoms are appropriate when they are not routinely associated with a definitive diagnosis. For left ankle pain, common clinical scenarios where M25.572 applies include:

• First-contact evaluation with no imaging or diagnostic workup completed
• Persistent ankle pain following a previously healed injury, where no new specific diagnosis has been established
• Chronic diffuse left ankle pain where the underlying etiology is still under investigation
• Post-surgical follow-up visits where residual pain is documented but no new structural finding is present

When a specific diagnosis is confirmed – plantar fasciitis (M72.2), Achilles tendinitis (M76.6-), or an ankle sprain (S93.4-) – the definitive code replaces M25.572. It is not appropriate to code both the symptom and the confirmed diagnosis unless the symptom is not routinely associated with the definitive condition. Using the Ottawa Ankle Rules during the initial assessment can help clinicians determine when imaging is warranted, which in turn affects whether M25.572 or a more specific code is appropriate at that visit.

Symptom vs. Definitive Diagnosis: Quick Reference

• Use M25.572: Pain is the primary documented finding with no specific underlying condition confirmed
• Do not use M25.572: A condition such as plantar fasciitis, Achilles tendinopathy, tarsal tunnel syndrome, or osteoarthritis has been diagnosed
• May use M25.572 additionally: Only when the symptom represents a distinct condition not integral to the primary diagnosis

M25.572 vs. Related ICD-10 Codes

Laterality confusion is one of the most common coding errors for ankle pain. The M25.57x family includes three codes, each covering a distinct anatomical presentation. Selecting the wrong one causes claim rejection and potential compliance issues. For broader context on ICD-10 coding for other musculoskeletal conditions, the same laterality logic applies across the M25 category.

M25.572 vs. M25.579: M25.579 should only be used when the treating clinician genuinely cannot document laterality – such as in an emergency setting with a minimally responsive patient and no available history. In standard outpatient, physical therapy, or podiatry encounters, the chart should always document which ankle is affected. Using M25.579 when left-side laterality is documented constitutes a specificity failure and may trigger payer audits. For chiropractic practice management workflows handling bilateral presentations, each side should be coded separately with M25.571 and M25.572 as appropriate.

Excludes2 Notes for ICD-10 Code M25.572

The Excludes2 note for M25.572 is one of the most misunderstood aspects of this code. An Excludes2 note means the excluded condition is not included in M25.572 but can be used together with it if the patient has both conditions separately. The codes listed under M25.572’s Excludes2 note are:

• M79.64- (Pain in hand and fingers) – excluded; use the appropriate M79.64x code if the patient has hand or finger pain in addition to left ankle pain
• M79.67- (Pain in foot and toes) – excluded; if the pain is specifically in the foot/toes rather than the ankle joint, use M79.67x
• M79.6- (Pain in limb) – excluded; this broader category should not be combined with M25.572 for the same anatomical site

In practical billing terms: if a patient presents with left ankle joint pain (M25.572) and separately documents pain in their right hand (M79.641), you can report both codes on the same claim. What you cannot do is use M25.572 alongside M79.671 (Pain in right foot and toes) as a way of capturing pain that overlaps anatomically. Review related ICD-10 diagnostic codes for other examples of how Excludes1 and Excludes2 notes interact across different code categories.

Documentation Requirements for ICD-10 Code M25.572

Accurate documentation is what keeps M25.572 claims clean on the first pass. Payers reviewing musculoskeletal claims look for specific elements that justify the symptom-level code and confirm that a definitive diagnosis was not available or established at the time of the visit. These elements belong in every encounter note where M25.572 is used:

• Laterality confirmed in the subjective note: The note must explicitly name the “left ankle” or “left foot” – not just “ankle pain”
• Pain location and character: Onset, duration (acute vs. chronic), constant vs. intermittent, weight-bearing vs. at rest, character (sharp, dull, burning, throbbing)
• Physical examination findings: Point tenderness location (medial malleolus, lateral ligament complex, subtalar joint line, plantar surface), swelling, erythema, crepitus, range-of-motion deficits
• Ruling out specific diagnoses: Document why a more specific code is not yet warranted – imaging pending, exam findings non-specific, no confirmed plantar fasciitis (M72.2), Achilles tendinopathy (M76.6-), ankle sprain (S93.4-), or osteoarthritis (M19.07-). If any of those conditions is established, switch to the definitive code at the next visit.
• Functional impact for medical necessity: Gait changes, activity limitations, ROM measurements (e.g., dorsiflexion in degrees), inability to perform specific occupational or sport-related tasks. Payers reviewing LCDs for physical medicine services expect measurable functional documentation.

For physical therapists, the SOAP note structure supports M25.572 well when the subjective and objective sections clearly delineate left-sided symptoms and the assessment section avoids attributing pain to a specific structure before evaluation is complete. Practices using patient records software with structured clinical note templates can build these elements as required fields, reducing the chance of documentation gaps on submission. For practices integrating return-to-activity protocols into their workflow, M25.572 often appears in the early evaluation visits before a more specific functional diagnosis is established.

Streamline Musculoskeletal Claim Submissions

Pabau's claims management tools help physical therapy, podiatry, and orthopedic practices flag coding conflicts, attach supporting documentation, and reduce denials for ICD-10 codes like M25.572 before claims leave the practice.

Book a demo

CPT Codes Commonly Paired with M25.572

M25.572 pairs with a defined set of CPT codes covering evaluation, imaging, conservative treatment, and procedural management of left ankle pain. Pairing accuracy matters as much as code selection: payers apply medical-necessity edits that look at the relationship between the procedure code and the diagnosis code. The codes below are the most consistent pairings for M25.572 in physical medicine, podiatry, sports medicine, and orthopedic billing.

LCD verification caveat. Medicare Local Coverage Determinations (LCDs) and commercial payer policies define which ICD-10 codes support specific CPT codes for medical necessity. M25.572 appears in many MAC LCDs for E&M, ankle imaging, and physical therapy services, but coverage varies by region and payer. Verify the relevant LCD before submitting claims for higher-cost services such as MRI (73721/73718), advanced ultrasound, or repeat injection procedures. Practices using claims management software with built-in payer policy alerts catch most LCD-driven denial risks before claims leave the practice. For musculoskeletal-focused operations, sports medicine software with integrated billing reduces the manual cross-checking burden across these code combinations.

ICD-9-CM Crosswalk for M25.572

Practices reconciling historical billing data, working with legacy systems, or handling retrospective audits will encounter ICD-9-CM codes. The approximate crosswalk for ICD-10 Code M25.572 is ICD-9-CM 719.47 (Pain in joint, ankle and foot). The mapping is approximate, not exact, because the ICD-9 code did not capture laterality. A single ICD-9 claim coded as 719.47 could represent right, left, or unspecified-laterality ankle and foot pain in ICD-10.

The practical implication for cross-period analysis: a claim filed under 719.47 before October 1, 2015 may correspond to any of the three ICD-10 successors depending on which side was clinically affected. Compliance teams reviewing pre- and post-transition records should not assume one-to-one equivalence. The expanded laterality requirement was the main driver behind M25.571/M25.572/M25.579 displacing the older single code.

Common Denial Patterns and How to Avoid Them

Left ankle pain claims that fail typically fail for one of four predictable reasons. Each has a clean fix that belongs in the pre-submission workflow.

• Laterality omission: The clinical note documents “left ankle” but the claim carries M25.579 (unspecified ankle/foot pain). Fix: build a laterality-required field into the EHR documentation template, and configure the billing system to flag M25.579 for review whenever the chart contains “left” or “right” in the assessment.
• Defaulting to M25.579 when left side is documented: Closely related to laterality omission – some practices use M25.579 as a habit when a chart reviewer is uncertain. M25.572 is the correct code whenever the left side is clinically documented; M25.579 is reserved for cases where laterality is genuinely undocumented or undeterminable. Auditors flag overuse of M25.579 in practices where laterality data exists in the chart.
• Mismatching CPT to anatomical site: Submitting M25.572 (left ankle) with a CPT code that targets the right side, or with imaging targeting a different region of the lower extremity. Fix: verify CPT-modifier alignment (LT/RT modifiers on procedural codes) and re-check side-of-service documentation before submission.
• Coding M25.572 alongside a definitive diagnosis when the symptom is integral: Once plantar fasciitis (M72.2), Achilles tendinopathy (M76.6-), or ankle sprain (S93.4-) is confirmed, the symptom code is generally not separately reportable – the pain is integral to the established condition. Fix: at the visit where a definitive diagnosis is recorded, transition the primary code on subsequent claims to the definitive diagnosis and drop M25.572 unless documentation supports a clinically distinct symptom layer.
• Excludes2 conflict: M25.572 submitted alongside M79.671 (right foot pain) or M79.6- on the same claim with anatomical overlap. Fix: review code combinations at the time of charge capture; the Excludes2 note allows both codes only when the conditions are distinct and affect different anatomical sites.

Specialty-Specific Use Cases for M25.572

Three specialties account for the majority of M25.572 claims: physical therapy, podiatry, and sports medicine. Each has nuances that affect how the code is applied and supported in documentation.

Physical Therapy

Physical therapists typically use M25.572 during the initial evaluation and early treatment visits before a physician-assigned diagnosis is available. The PT’s role is to document functional impairment, not to diagnose pathology. Linking M25.572 to specific functional goals (e.g. “improve left ankle dorsiflexion from 5 degrees to 15 degrees within 6 visits”) strengthens medical necessity and supports the plan of care. Practices with physical therapy EMR systems that template these goal statements reduce documentation time without sacrificing specificity.

Podiatry

Podiatrists use M25.572 most often in the early stages of a diagnostic workup for unexplained ankle pain or when a patient transfers from another provider without complete records. Once imaging confirms a specific condition, the podiatrist should update the primary diagnosis code. Medicare podiatry claims are subject to close scrutiny for medical necessity, and using a symptom code when a specific diagnosis is available is a common audit trigger. Always document why the definitive diagnosis has not yet been established if using M25.572 beyond the first one or two visits.

Sports Medicine and Orthopedics

Sports medicine physicians frequently use M25.572 in sideline and rapid-access clinic settings where imaging is not immediately available. The code supports E&M and initial imaging orders. Once MRI or X-ray results confirm a specific injury – such as a lateral ligament tear or osteochondral defect – the treating physician should use the appropriate acute injury or structural code for subsequent visits. The AAPC Codify ICD-10-CM lookup is a practical tool for confirming the most specific available code once imaging results are in.

Expert Picks

Managing physical therapy billing workflows? Physical Therapy EMR covers how purpose-built practice management tools reduce coding errors and denial rates for musculoskeletal outpatient practices.

Running a sports medicine or orthopedic clinic? Sports Medicine Software supports the documentation and billing workflows specific to athletic injury and post-injury rehabilitation cases.

Need a billing validation layer for musculoskeletal claims? Claims Management Software helps practices catch Excludes2 conflicts, laterality mismatches, and CPT-to-ICD specificity gaps before claims are submitted.

Conclusion

Left ankle pain claims fail most often for one of three reasons: using a symptom code when a specific diagnosis is already documented, selecting the unspecified laterality code M25.579 when the chart clearly states left-sided, or triggering an Excludes2 conflict by pairing M25.572 with a limb or foot pain code for the same anatomical site. Getting ICD-10 Code M25.572 right requires accurate clinical documentation that confirms laterality, symptom character, and the absence of a confirmed specific diagnosis at the time of the encounter.

Pabau’s claims management software helps musculoskeletal practices catch these errors before submission – flagging code conflicts, checking documentation completeness, and reducing the denial cycle that costs practices time and revenue. To see how it works for physical therapy, podiatry, and sports medicine practices, book a demo.

Frequently Asked Questions