Z44.122
BillableEncounter for fitting and adjustment of partial artificial left leg
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is Z44.122 an HCC code?
Yes. Z44.122 maps to Amputation Status, Lower Limb/Amputation Complications under the CMS-HCC V28 risk adjustment model (and Amputation Status, Lower Limb/Amputation Complications under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for Z44.122
For Z44.122to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed Z44.122 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
Z44.122 is the ICD-10-CM diagnosis code for encounter for fitting and adjustment of partial artificial left leg. A patient visit to have a partial artificial left leg fitted or adjusted to ensure proper function and comfort. Z44.122 sits in the ICD-10-CM chapter for factors influencing health status and contact with health services (z00-z99), within the section covering encounters for other specific health care (z40-z53).
Under the CMS-HCC V28 risk adjustment model, Z44.122 maps to Amputation Status, Lower Limb/Amputation Complications (HCC 409) with a community, non-dual, aged base RAF weight of 0.598. Under the older V24 model, Z44.122 mapped to the same category but with a base RAF weight of 0.519 — V28 recalibrated weights across the entire model. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
This code is specific to the left leg; use Z44.121 for right leg and Z44.129 when laterality is not specified. Because Z44.122 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for Z44.122 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
Clinical Significance
This code indicates a patient has undergone partial lower limb amputation on the left side requiring prosthetic management, representing moderate functional impairment. Partial prosthetics typically involve below-knee or similar amputations with preserved joint function above the amputation site.
Documentation Requirements
- ✓Documentation specifying partial artificial leg prosthetic
- ✓Clear indication this is for left leg prosthesis
- ✓Type of encounter (fitting, adjustment, repair, replacement)
- ✓Patient's underlying partial amputation status
- ✓Level of amputation requiring partial prosthetic (e.g., below-knee)
- ✓Functional assessment and prosthetic goals
- ✓Provider specialty performing prosthetic services
- ✓Any complications with current partial prosthetic device
Commonly Confused Codes
- •Z44.102 — Use when prosthetic type is unspecified rather than partial
- •Z44.112 — Use when documentation specifies complete rather than partial prosthetic
- •Z44.121 — Use for right leg instead of left leg partial prosthetic
- •Z44.129 — Use when laterality is unspecified for partial prosthetic
- •Z89.412 — This is amputation status, not prosthetic encounter