ICD-10-CM 2027
ICD-10 code for nerve disorder
From the official ICD-10-CM alphabetic index entry “Disorder (of) › nerve”. Page updated September 29, 2026.
About coding nerve disorder
The ICD-10-CM code for nerve disorder is G58.9 (Mononeuropathy, unspecified). The official index lists 35 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on G58.9.
Within G58, choose G58.9 (Mononeuropathy, unspecified) only when documentation doesn't support a more specific option: intercostal neuropathy (G58.0), mononeuritis multiplex (G58.7) and other specified mononeuropathies (G58.8).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 073 (Cranial and Peripheral Nerve Disorders with MCC, relative weight 1.5779) and DRG 074 (Cranial and Peripheral Nerve Disorders without MCC, relative weight 1.0173), in MDC 01 (Diseases and Disorders of the Nervous System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific nerve disorder codes (official index)
- abducent NEC
- accessory G52.8 — Disorders of other specified cranial nerves
- acoustic
- auditory
- auriculotemporal G50.8 — Other disorders of trigeminal nerve
- axillary G54.0 — Brachial plexus disorders
- cerebral
- cranial G52.9 — Cranial nerve disorder, unspecified
- eighth
- eleventh G52.8 — Disorders of other specified cranial nerves
- fifth G50.9 — Disorder of trigeminal nerve, unspecified
- first G52.0 — Disorders of olfactory nerve
- fourth NEC
- multiple G52.7 — Disorders of multiple cranial nerves
- ninth G52.1 — Disorders of glossopharyngeal nerve
- second NEC
- seventh NEC G51.8 — Other disorders of facial nerve
- sixth NEC
- specified NEC G52.8 — Disorders of other specified cranial nerves
- tenth G52.2 — Disorders of vagus nerve
- third NEC
- twelfth G52.3 — Disorders of hypoglossal nerve
- entrapment
- facial G51.9 — Disorder of facial nerve, unspecified
- specified NEC G51.8 — Other disorders of facial nerve
- femoral
- glossopharyngeal NEC G52.1 — Disorders of glossopharyngeal nerve
- hypoglossal G52.3 — Disorders of hypoglossal nerve
- intercostal G58.0 — Intercostal neuropathy
- lateral
- cutaneous of thigh
- popliteal
- lower limb
- medial popliteal
- median NEC
- multiple G58.7 — Mononeuritis multiplex
- oculomotor NEC
- olfactory G52.0 — Disorders of olfactory nerve
- optic NEC H47.09 — Other disorders of optic nerve, not elsewhere classified
- hemorrhage into sheath
- ischemic H47.01 — Ischemic optic neuropathy
- peroneal
- phrenic G58.8 — Other specified mononeuropathies
- plantar
- pneumogastric G52.2 — Disorders of vagus nerve
- posterior tibial
- radial
- recurrent laryngeal G52.2 — Disorders of vagus nerve
- root G54.9 — Nerve root and plexus disorder, unspecified
- cervical G54.2 — Cervical root disorders, not elsewhere classified
- lumbosacral G54.1 — Lumbosacral plexus disorders
- specified NEC G54.8 — Other nerve root and plexus disorders
- thoracic G54.3 — Thoracic root disorders, not elsewhere classified
- sciatic NEC
- specified NEC G58.8 — Other specified mononeuropathies
- lower limb
- upper limb
- sympathetic G90.9 — Disorder of the autonomic nervous system, unspecified
- tibial
- trigeminal G50.9 — Disorder of trigeminal nerve, unspecified
- specified NEC G50.8 — Other disorders of trigeminal nerve
- trochlear NEC
- ulnar
- upper limb
- vagus G52.2 — Disorders of vagus nerve
Common questions about nerve disorder ICD-10 codes
What is the ICD-10 code for nerve disorder?
- G58.9 — Mononeuropathy, unspecified. More specific codes apply when the documentation supports them: G52.8, G50.8, G54.0, G52.9 and others below.
What is the ICD-10 code for accessory nerve disorder?
- G52.8 — Disorders of other specified cranial nerves.
What is the ICD-10 code for auriculotemporal nerve disorder?
- G50.8 — Other disorders of trigeminal nerve.
What is the ICD-10 code for axillary nerve disorder?
- G54.0 — Brachial plexus disorders.
What is the ICD-10 code for cranial nerve disorder?
- G52.9 — Cranial nerve disorder, unspecified.
What is the ICD-10 code for facial nerve disorder?
- G51.9 — Disorder of facial nerve, unspecified.
What is the ICD-10 code for glossopharyngeal nec nerve disorder?
- G52.1 — Disorders of glossopharyngeal nerve.
Is G58.9 billable?
- Yes. G58.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can G58.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict G58.9 as a principal diagnosis.
Is G58.9 a CC or MCC?
- No. G58.9 is neither a CC nor an MCC under MS-DRG v44.0.