ICD-10-CM · Spine

M50.13

Cervical disc disorder with radiculopathy localized to the cervicothoracic region (C7-T1), where disc pathology compresses or irritates the C8 nerve root, producing radiating neurological symptoms into the arm and hand.

Verified May 8, 2026 · 6 sources ↓

Status
Billable
Chapter
13
Related CPT
6
Region
Spine
Drawn from CDCICD10DataAAPCOutsourcestrategiesMdclarity

Documentation tips

What should appear in the chart to support M50.13.

Source · Editorial brief grounded in 6 cited references ↓

  • Specify the disc level as C7-T1 or describe the region as cervicothoracic; vague 'lower cervical' language leaves the level ambiguous and may force a drop to M50.10.
  • Document objective neurological findings consistent with C8 radiculopathy: ring/little finger paresthesias, intrinsic hand weakness, diminished triceps or finger flexor reflex.
  • Record imaging findings (MRI or CT myelography) that confirm disc herniation or foraminal stenosis at C7-T1 — include modality, date, and relevant finding (e.g., right paracentral disc herniation with C8 nerve root compression).
  • Distinguish radiculopathy from myelopathy in the clinical assessment; if both are present, code myelopathy first (M50.03) and query the provider about the primary pathology.
  • Note the history of conservative treatment (physical therapy, NSAIDs, oral steroids) when supporting medical necessity for interventional procedures billed alongside this code.

Related CPT procedures

Procedure codes commonly billed with M50.13. Linking the right diagnosis to the right procedure is what establishes medical necessity.

Source · CMS LCDs · AAOS specialty guidance · claims-pattern analysis

Common coding pitfalls

The recurring mistakes coders make with M50.13 and adjacent codes.

Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓

  • Coding M50.13 for axial neck pain alone without documented radicular symptoms — disc degeneration at C7-T1 without radiculopathy codes to M50.33, not M50.13.
  • Assigning M50.13 when the affected level is C5-C6 or C6-C7 — those mid-cervical levels belong under M50.122 or M50.123; M50.13 is exclusive to C7-T1.
  • Confusing radiculopathy with myelopathy: spinal cord signal change, gait disturbance, or hyperreflexia drives a switch to M50.03, not M50.13.
  • Using an unspecified parent code (M50.10) when the provider has clearly documented C7-T1 or C8 involvement — specificity is available and required when documented.
  • Appending a 7th-character extension to M50.13 — M-codes in Chapter 13 do not use encounter-type extensions (A/D/S); those apply only to injury codes.

Clinical context

Source · Editorial summary grounded in 6 cited references ↓

M50.13 is the correct code when disc pathology at the C7-T1 level produces radiculopathy — specifically C8 nerve root irritation or compression. The applicable-to notes in the ICD-10-CM Tabular List confirm this: M50.13 covers C7-T1 disc disorder with radiculopathy and C8 radiculopathy due to disc disorder. If the disc level is not documented or falls outside C7-T1, this code does not apply — use M50.10 (unspecified cervical region) or the appropriate level-specific code under M50.12 for mid-cervical involvement.

Radiculopathy must be documented as the principal feature, not inferred. A patient with disc degeneration at C7-T1 and only axial neck pain codes to M50.33 (other cervical disc degeneration, cervicothoracic region), not M50.13. If disc pathology at this level causes myelopathy — spinal cord involvement — code instead to M50.03. Radiculopathy and myelopathy are mutually exclusive under the M50 subcategory structure; choose based on documented clinical findings.

The cervicothoracic region sits at the transition zone between the mobile cervical spine and the stiffer thoracic segment. C8 radiculopathy classically presents with pain and paresthesias radiating into the ring and little fingers, intrinsic hand weakness, and diminished triceps or finger flexor reflexes. Documenting these specific neurological deficits — along with MRI or CT myelography confirming C7-T1 disc herniation or foraminal stenosis — anchors the M50.13 assignment and supports medical necessity for both conservative and surgical interventions.

Inclusion & exclusion notes

Per the official ICD-10-CM Tabular List.

Source · CDC ICD-10-CM Official Tabular List · 2026

Includes

  • C7-T1 disc disorder with radiculopathy
  • C8 radiculopathy due to disc disorder

Sibling codes

Other billable codes under M50.1 (laterality / anatomic variants).

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01What disc level does M50.13 cover?
M50.13 covers the C7-T1 intervertebral disc level, also described as the cervicothoracic region. The ICD-10-CM applicable-to notes confirm it captures C7-T1 disc disorder with radiculopathy and C8 radiculopathy due to disc disorder.
02Can M50.13 be used for bilateral C8 radiculopathy?
Yes. M50.13 does not carry laterality in its structure — it identifies region, not side. Document bilateral involvement in the clinical notes; a single M50.13 code is appropriate. If payers require additional granularity, check payer-specific guidelines, but the ICD-10-CM code itself is not lateralized at this level.
03When should I use M50.03 instead of M50.13?
Use M50.03 when the C7-T1 disc disorder causes myelopathy — spinal cord compression with cord signal change on MRI, hyperreflexia, gait disturbance, or upper motor neuron signs. M50.13 applies when the pathology irritates or compresses the nerve root (lower motor neuron, radicular pattern) without cord involvement.
04Is M50.13 valid without imaging confirmation?
The code is billable based on clinical diagnosis. However, documenting imaging findings (MRI or CT myelography confirming C7-T1 disc pathology) is critical for medical necessity, prior authorization for procedures, and audit defense. A clinical diagnosis of C8 radiculopathy without imaging will often trigger payer requests for additional documentation.
05What is the MS-DRG grouping for M50.13?
M50.13 groups to MS-DRG 551 (Medical back problems with MCC) or MS-DRG 552 (Medical back problems without MCC) under MS-DRG v43.0, per ICD-10-CM data. The MCC distinction depends on comorbidities documented in the same encounter.
06Can M50.13 be the primary diagnosis for a cervical epidural steroid injection claim?
Yes. M50.13 supports medical necessity for CPT 62321 (cervicothoracic interlaminar epidural injection with imaging guidance) and CPT 64479 (transforaminal epidural injection, cervical/thoracic). Ensure the procedure level matches the documented C7-T1 pathology and that prior conservative care is on record when required by the payer.
07How does M50.13 differ from M54.12 (radiculopathy, cervical region)?
M50.13 specifies that a disc disorder is the identified cause of the radiculopathy at C7-T1. M54.12 is used for cervical radiculopathy when the etiology is not a documented disc disorder — for example, foraminal stenosis from spondylosis without a discrete disc herniation. If the imaging and clinical documentation identify a disc as the causative structure, M50.13 is the more specific and correct code.

Mira AI Scribe

The Mira AI Scribe captures the disc level (C7-T1), the laterality of nerve root compression, objective neurological deficits consistent with C8 involvement (finger paresthesias, grip weakness, reflex changes), and imaging confirmation of foraminal stenosis or herniation. That specificity locks in M50.13 over the unspecified M50.10 and prevents downcoding or payer queries requesting additional documentation to support medical necessity.

See how Mira captures M50.13 documentation

Related ICD-10 codes

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