Audit Defense

2026 Medicare and Commercial Payer Audits Target Physical Therapy Billing (CPT 97110‑97530): Defending Medical Necessity, Visit Frequency, and Modifier KX Documentation

Medicare Administrative Contractors have stepped up Targeted Probe and Educate (TPE) efforts in 2026, and therapy codes are a prime focus. When a MAC letter arrives requesting records for CPT 97110 (therapeutic exercise) or 97530 (therapeutic activities), it isn’t random. CMS uses analytics to pinpoint billing patterns suggesting overuse, incorrect KX modifier use, or weak documentation of medical necessity. Major commercial payers such as UnitedHealthcare and Cigna are running similar reviews that parallel CMS priorities.

The TPE Connection: Data‑Driven Scrutiny, Not Routine Sampling

As outlined in the RACmonitor report, CMS designed TPE to align what’s billed with what’s documented. A MAC typically samples a few dozen therapy claims, comparing each note with its corresponding claim. When discrepancies appear, the contractor provides one‑on‑one education and allows time for corrective action before another review. After three failed cycles, CMS can escalate to full prepayment review or refer the provider to a Recovery Auditor.

Quick EMR notes, vague explanations like “improved mobility,” or repeated therapy goals across visits can sink a review. CDI, coding, and therapy management must coordinate closely when addressing findings, CMS has stated that the same gaps found before submission tend to reappear during review.

PT Codes 97110-97530: What Auditors Are Watching

Therapy billing seems straightforward, yet each CPT code carries specific intent:

  • 97110 - Therapeutic exercise, direct one‑on‑one, focused on strength, endurance, range of motion, flexibility.
  • 97112 - Neuromuscular re‑education, targeting balance, coordination, and proprioception.
  • 97530 - Therapeutic activities, dynamic functional movements tied to daily‑living tasks.

Auditors are honing in on whether documentation distinguishes these services. If every session reflects the same code mix no matter the treatment plan, it signals templated billing. Combine that with high unit counts or repetitive activity over time, and it resembles low complexity with high utilization, a clear audit trigger.

MACs also check therapy frequency against diagnosis codes and plan‑of‑care updates. Long runs of visits under ICD‑10 M25.561 (pain in right knee) without measurable progress or objective metrics point to missing medical necessity. Even when the plan is appropriate, the progress must be clearly shown.

Modifier KX and Documentation Integrity: A Frequent Trouble Spot

The KX modifier tells CMS the therapy is medically necessary beyond the usual threshold and that supporting documents exist. Auditors expect to see plan‑of‑care signatures, updated progress reports, and functional scores backing that need.

Too often, billers attach KX assuming it guarantees payment, skipping verification that notes truly justify continuation. When TPE reviewers find missing or outdated rationale, they view KX as an unsupported attestation, often leading from first‑round education to prepayment hold. UHC and Anthem post‑payment reviews follow suit. KX without contemporaneous documentation brings recoupment risk months later.

Therapists tend to trust a detailed narrative alone. Auditors expect specific ties between impairment data, strength values, range of motion, and the skilled interventions required. The record has to illustrate why a home exercise plan alone would be insufficient. Without that link, it reads as maintenance, not skilled care.

Cross‑Team Accountability and Real‑Time Fixes

Compliance departments alone can’t carry a TPE cycle. According to RACmonitor, the program connects CDI, coding, and utilization review. A claim failing audit already failed at documentation design. So, where to focus now?

  • Audit templates for repetitive language. EMR automation easily clones visits.
  • Document measurable functional outcomes every 10 visits or at plan renewal.
  • Before submitting KX‑flagged lines, confirm updated therapist justification within the same date range.
  • Arrange combined training for therapy, coding, and compliance teams, clarifying what reviewers notice first in a PT note.

Don’t wait for a probe letter. Once it arrives, you’re in a structured three‑round process where failure leads to extrapolation. Building solid, defensible documentation around CPT 97110-97530 now avoids that scramble later. And when commercial payers align with Medicare’s model, as they tend to, your compliance data will already be ready.

Sources

Claims Assistant