G83.4 ICD-10-CM Code: Cauda equina syndrome
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)
G83.4
Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidanceCauda equina syndrome
A serious condition where the bundle of nerves at the base of the spinal cord is compressed or damaged, causing weakness or loss of function in the legs and loss of bladder/bowel control.
Buddy Insight
Cauda equina syndrome is a surgical emergency caused by compression of the nerve bundle at the base of the spinal cord, resulting in lower extremity weakness, saddle anesthesia, and bowel/bladder dysfunction.
CMS-HCC V28
MappedHCC 182
RAF 0.282
CMS-HCC V24
MappedHCC 72
RAF 0.464
ACA/HHS
00
RAF 0
ESRD/PACE
MappedHCC 72
RAF 0.0
RXHCC
MappedHCC 155
RAF 0.0
Code Trumping
Basket needed
Code Book Path
Inclusion Terms
Official- Neurogenic bladder due to cauda equina syndrome
Excludes 2
OfficialICD-10-CM does not list Excludes 2 notes for G83.4 in this effective period.
Related Child Codes
Includes
Official- paralysis (complete) (incomplete), except as in G80-G82
Excludes 1
Official- cord bladder NOS (G95.89)
- neurogenic bladder NOS (N31.9)
Code First
OfficialICD-10-CM does not list Code First sequencing instructions for G83.4 in this effective period.
Use Additional
OfficialICD-10-CM does not list Use Additional Code instructions for G83.4 in this effective period.
Code Also
OfficialICD-10-CM does not list Code Also instructions for G83.4 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 G83.4 an HCC code?
Yes. G83.4 maps to Spinal Cord Disorders/Injuries under the CMS-HCC V28 risk adjustment model (and Spinal Cord Disorders/Injuries 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 G83.4
For G83.4to 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 G83.4 during that encounter, not just copy-forwarded from a problem list.
What This Code Means
G83.4 is the ICD-10-CM diagnosis code for cauda equina syndrome. A serious condition where the bundle of nerves at the base of the spinal cord is compressed or damaged, causing weakness or loss of function in the legs and loss of bladder/bowel control. G83.4 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, G83.4 maps to Spinal Cord Disorders/Injuries (HCC 182) with a community, non-dual, aged base RAF weight of 0.282. Under the older V24 model, G83.4 mapped to the same category but with a base RAF weight of 0.464, 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.
Document the underlying cause (herniated disc, trauma, tumor) as it may affect treatment and prognosis coding. Because G83.4 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 G83.4 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Document the underlying cause (herniated disc, trauma, tumor) as it may affect treatment and prognosis coding
- •This is a medical emergency requiring immediate intervention; ensure acute presentation is captured if applicable
Clinical Significance
Cauda equina syndrome is a surgical emergency caused by compression of the nerve bundle at the base of the spinal cord, resulting in lower extremity weakness, saddle anesthesia, and bowel/bladder dysfunction. Early recognition and surgical decompression are critical to prevent permanent neurological damage. This condition drives significant acute care resource utilization and often results in long-term functional deficits requiring ongoing management.
Documentation Requirements
- ✓Diagnosis of cauda equina syndrome explicitly stated
- ✓Underlying cause (disc herniation, tumor, abscess, fracture, etc.)
- ✓Neurological findings: saddle anesthesia, lower extremity weakness/numbness
- ✓Bladder and bowel function status (retention, incontinence)
- ✓Surgical intervention documentation if performed
- ✓Acute vs. chronic presentation status
- ✓Ongoing residual deficits if present
- ✓Active follow-up and management plan
Commonly Confused Codes
- •G82.20 Paraplegia, unspecified: bilateral lower extremity paralysis without cauda equina involvement
- •M51.16 Intervertebral disc disorder with radiculopathy, lumbar: disc disease without cauda equina compression
- •M48.06 Spinal stenosis, lumbar: narrowing without cauda equina involvement
- •G95.89 Other specified diseases of spinal cord: other spinal cord conditions
- •S34.3 Injury of cauda equina: use for traumatic injury to the cauda equina