2026 ICD-10-CM Diagnosis Code Q05.4Unspecified spina bifida with hydrocephalus

ICD-10-CM Codes›Q00-Q99›Q00-Q07›Q05

ICD-10-CM Q05.4
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

Q05.4 is a billable ICD-10-CM diagnosis code for unspecified spina bifida with hydrocephalus. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). The code is exempt from POA reporting. Coders also document this condition as meningomyelocele. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nervous system congenital anomalies.

Code Identity

ICD-10-CM Code
Q05.4
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified spina bifida with hydrocephalus
Short Description
Unspecified spina bifida with hydrocephalus
Same as the full description in the CMS dataset.
Parent Code
Q05
Spina bifida

Code Classification

ChapterQ00-Q99Congenital malformations, deformations and chromosomal abnormalities
SectionQ00-Q07Congenital malformations of the nervous system
CategoryQ05Spina bifida
This CodeQ05.4Unspecified spina bifida with hydrocephalus

Present on Admission (POA)Billing

Q05.4 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Meningomyelocele
  • Myelocele with hydrocephalus
  • Myelomeningocele and hydrocephalus
  • Rachischisis
  • Rachischisis with hydrocephalus
  • Spina bifida with hydrocephalus
  • Spina bifida with hydrocephalus - closed
  • Spina bifida with hydrocephalus - open
  • Spina bifida with hydrocephalus of late onset

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Hydrocephalus(acquired) (external) (internal) (malignant) (recurrent)
      • congenital (external) (internal)
        • with spina bifida
    • Spina bifida(aperta)
      • with hydrocephalus NEC

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR MAL004
Nervous system congenital anomalies
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Meningomyelocele

    congenital, or rarely acquired, herniation of meningeal and spinal cord tissue through a bony defect in the vertebral column. the majority of these defects occur in the lumbosacral region. clinical features include paraplegia, loss of sensation in the lower body, and incontinence. this condition may be associated with the arnold-chiari malformation and hydrocephalus. (from joynt, clinical neurology, 1992, ch55, pp35-6)

Patient EducationClinical

Hydrocephalus

Hydrocephalus is the buildup of too much cerebrospinal fluid in the brain. Normally, this fluid cushions your brain. When you have too much, though, it puts harmful pressure on your brain.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert Q05.4 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
741.00 Spin bif w hydroceph NOS
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About Q05.4Overview

Is Q05.4 (Spina bifida) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unspecified spina bifida with hydrocephalus on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is Q05.4 exempt from POA reporting?

Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for unspecified spina bifida with hydrocephalus on inpatient claims.

What is the ICD-9 equivalent of Q05.4?

Under the General Equivalence Mappings, unspecified spina bifida with hydrocephalus converts to ICD-9-CM 741.00 (spin bif w hydroceph NOS). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.