G82.51 ICD-10-CM Code: Quadriplegia, C1-C4 complete
HCC Buddy Code Card
Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.
FY 2026 Apr update / Diseases of the nervous system (G00-G99) / Cerebral palsy and other paralytic syndromes (G80-G83)
G82.51
Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidanceQuadriplegia, C1-C4 complete
Complete paralysis of all four limbs resulting from injury to the upper cervical spinal cord (C1-C4 vertebrae level), with total loss of motor and sensory function below the injury.
Buddy Insight
Complete quadriplegia at the C1-C4 level represents the most severe form of spinal cord injury with total loss of function in all four extremities and typically requiring mechanical ventilation.
CMS-HCC V28
MappedHCC 180
RAF 0.274
CMS-HCC V24
MappedHCC 70
RAF 0.885
ACA/HHS
00
RAF 0
ESRD/PACE
MappedHCC 70
RAF 0.0
RXHCC
00
RAF 0
Code Trumping
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Code Book Path
Inclusion Terms
OfficialICD-10-CM does not list inclusion terms for G82.51 in this effective period.
Excludes 2
OfficialICD-10-CM does not list Excludes 2 notes for G82.51 in this effective period.
Related Child Codes
Includes
OfficialICD-10-CM does not list Includes notes for G82.51 in this effective period.
Excludes 1
OfficialICD-10-CM does not list Excludes 1 notes for G82.51 in this effective period.
Code First
OfficialICD-10-CM does not list Code First sequencing instructions for G82.51 in this effective period.
Use Additional
OfficialICD-10-CM does not list Use Additional Code instructions for G82.51 in this effective period.
Code Also
OfficialICD-10-CM does not list Code Also instructions for G82.51 in this effective period.
Buddy Documentation Tip
MEAT Support
Audit Caution
Common Mistakes
Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.
Is G82.51 an HCC code?
Yes. G82.51 maps to Quadriplegia under the CMS-HCC V28 risk adjustment model (and Quadriplegia 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 G82.51
For G82.51to 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 G82.51 during that encounter, not just copy-forwarded from a problem list.
What This Code Means
G82.51 is the ICD-10-CM diagnosis code for quadriplegia, c1-c4 complete. Complete paralysis of all four limbs resulting from injury to the upper cervical spinal cord (C1-C4 vertebrae level), with total loss of motor and sensory function below the injury. G82.51 sits in the ICD-10-CM chapter for diseases of the nervous system (g00-g99), within the section covering cerebral palsy and other paralytic syndromes (g80-g83).
Under the CMS-HCC V28 risk adjustment model, G82.51 maps to Quadriplegia (HCC 180) with a community, non-dual, aged base RAF weight of 0.274. Under the older V24 model, G82.51 mapped to the same category but with a base RAF weight of 0.885, 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.
Complete quadriplegia at C1-C4 level typically results in the most severe functional impairment and may require ventilator support. Because G82.51 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 G82.51 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Complete quadriplegia at C1-C4 level typically results in the most severe functional impairment and may require ventilator support
- •Ensure documentation specifies both the C1-C4 level and that the paralysis is complete before assigning this code
Clinical Significance
Complete quadriplegia at the C1-C4 level represents the most severe form of spinal cord injury with total loss of function in all four extremities and typically requiring mechanical ventilation. These patients are entirely dependent for all activities of daily living and are at extreme risk for respiratory failure, pressure injuries, autonomic dysreflexia, and numerous other complications. This is one of the most resource-intensive conditions in all of medicine.
Documentation Requirements
- ✓Documentation of complete quadriplegia specifying C1-C4 cervical level
- ✓Verification of complete loss of motor and sensory function below the injury
- ✓Ventilator dependency status if applicable
- ✓Underlying etiology (trauma, tumor, vascular, etc.)
- ✓Respiratory management plan
- ✓Full care dependency documentation
- ✓Bladder/bowel management approach
- ✓Skin integrity protocol
- ✓Active specialist care plan
Commonly Confused Codes
- •G82.52 Quadriplegia, C1-C4 incomplete: some function preserved at same level
- •G82.53 Quadriplegia, C5-C7 complete: lower cervical level with potentially more upper extremity function
- •G82.50 Quadriplegia, unspecified: use only when cervical level cannot be determined
- •G82.21 Paraplegia, complete: only lower extremities affected