ICD-10-CM · Spine

M49.84

Secondary spondylopathy affecting the thoracic spine, where the spinal pathology — including curvature, deformity, kyphosis, or scoliosis — is a manifestation of an underlying systemic or infectious disease coded elsewhere.

Verified May 8, 2026 · 3 sources ↓

Status: Billable
Chapter: 13
Related CPT: 13
Region: Spine

Drawn from CDCICD10DataAAPC

Documentation tips

What should appear in the chart to support M49.84.

Source · Editorial brief grounded in 3 cited references ↓

Identify the underlying disease by name and ensure it is coded first — M49.84 is always a secondary code per the 'Code first' tabular instruction.
Specify 'thoracic region' or reference thoracic vertebral levels (T1–T12) by name in the clinical note to justify the '84' site character over unspecified M49.80.
Document the type of spinal manifestation: whether the condition presents as kyphosis, scoliosis, vertebral deformity, or structural compromise, since these are inclusion terms that validate the code.
Record imaging findings (X-ray, MRI, CT) that confirm thoracic vertebral involvement — vertebral body collapse, endplate erosion, angular deformity, or loss of vertebral height.
Note any conservative or surgical management history relevant to the thoracic spondylopathy to support medical necessity when paired with spine procedure CPT codes.

Related CPT procedures

Procedure codes commonly billed with M49.84. Linking the right diagnosis to the right procedure is what establishes medical necessity.

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

72070 $33.07

Two-view radiologic examination of the thoracic spine, including AP and lateral projections of the 12 thoracic vertebrae.

72080 $35.07

Radiologic examination of the thoracolumbar junction (where the thoracic and lumbar spine meet), requiring a minimum of two views.

20610 $68.81

Aspiration and/or injection of a major joint or bursa (shoulder, hip, knee, or subacromial bursa) performed without ultrasound guidance.

22532 $1,732.17

Spinal fusion at a single thoracic vertebral segment using the lateral extracavitary approach, which provides a wide posterolateral corridor to the anterior and middle columns without entering the thoracic cavity. Includes minimal discectomy to prepare the interspace for fusion.

22533 $1,547.80

Spinal fusion of a lumbar vertebral segment performed through a lateral extracavitary approach, including minimal discectomy to prepare the interspace (not performed solely for decompression).

22534 $323.65

Add-on code for lateral extracavitary arthrodesis at each additional thoracic or lumbar vertebral segment beyond the first.

63030 $898.15

Single-interspace lumbar laminotomy with nerve root decompression, including partial facetectomy, foraminotomy, and/or herniated disc excision performed via open surgical technique.

99213 $95.19

Established patient office or outpatient visit requiring 20–29 minutes of total time or low-complexity medical decision-making.

99214 $135.61

Office visit for an established patient requiring moderate-complexity medical decision making (MDM), or 30–39 minutes of total provider time on the date of service.

99215 $192.39

Highest-level office or outpatient E/M visit for an established patient, qualifying via high-complexity medical decision making or 40–54 minutes of total provider time on the date of service.

72072 View procedure details

72074 View procedure details

77080 View procedure details

Common coding pitfalls

The recurring mistakes coders make with M49.84 and adjacent codes.

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

Sequencing M49.84 first — the underlying disease (e.g., brucellosis A23.-, osteitis fibrosa cystica E21.0) must be listed before M49.84 per mandatory tabular instruction.
Using M49.84 when the cause is on the Excludes1 list (e.g., Pott's disease, gonococcal spondylitis, tabes dorsalis spondylitis) — those conditions have their own dedicated codes and M49.84 cannot coexist with them.
Assigning M49.84 when the spondylopathy is thoracolumbar or cervicothoracic rather than purely thoracic — check M49.83 or M49.85 if the affected region spans a junction.
Applying M49.84 for enteropathic arthropathies of the spine — those code to M07.- per Excludes1, not to M49.

Clinical context

Source · Editorial summary grounded in 3 cited references ↓

M49.84 applies when a thoracic-region spondylopathy (vertebral deformity, abnormal curvature, or structural compromise) is directly caused by an underlying disease that carries its own primary code. Classic triggers include brucellosis (A23.-), Charcot-Marie-Tooth disease (G60.0), enterobacterial infections (A01–A04), and osteitis fibrosa cystica (E21.0). The tabular instruction is mandatory: code the underlying disease first, then M49.84 as the secondary code.

The category M49 explicitly includes curvature of spine, deformity of spine, kyphosis, and scoliosis when those conditions are caused by a disease classified elsewhere. However, it has a substantial Excludes1 list — conditions with their own dedicated codes. Specifically excluded are: Pott's disease/tuberculous spondylitis (A18.01), gonococcal spondylitis (A54.41), neuropathic spondylopathy in tabes dorsalis (A52.11), neuropathic spondylopathy in syringomyelia (G95.0), nonsyphilitic neuropathic spondylopathy NEC (G98.0), spondylitis in acquired syphilis (A52.77), typhoid fever spondylitis (A01.05), and enteropathic arthropathies (M07.-). Do not assign M49.84 when any of those conditions is the driver — the condition has its own code.

Within the M49.8 subcategory, thoracic-region specificity is captured by the 4th–5th character pair '84'. If documentation does not clearly specify the thoracic region (T1–T12 vertebrae), drop to M49.80 (unspecified site) or consider adjacent region codes M49.83 (cervicothoracic) or M49.85 (thoracolumbar) if the affected zone spans a junction.

Sibling codes

Other billable codes under M49.8 (laterality / anatomic variants).

M49.82

Spondylopathy in diseases classd elswhr, cervical region

M49.80

Spondylopathy in diseases classified elsewhere, site unsp

M49.86

Spondylopathy in diseases classd elswhr, lumbar region

M49.87

Spondylopathy in diseases classd elswhr, lumbosacral region

M49.81

Spond in diseases classd elswhr, occipt-atlan-ax region

M49.83

Spondylopathy in diseases classd elswhr, cervicothor region

M49.85

Spond in diseases classd elswhr, thoracolumbar region

M49.89

Spond in diseases classd elswhr, multiple sites in spine

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 3 cited references ↓

01Which code goes first — M49.84 or the underlying disease?

The underlying disease always goes first. The ICD-10-CM tabular list includes a mandatory 'Code first' instruction at the M49 category level. M49.84 is always a secondary code.

02Can M49.84 be used for a patient with Pott's disease affecting the thoracic spine?

No. Pott's disease (tuberculous spondylitis) codes to A18.01. It appears on the M49 Excludes1 list, meaning M49.84 cannot be used simultaneously. Assign A18.01 alone for that condition.

03What is the difference between M49.84 and M49.85?

M49.84 specifies the thoracic region (T1–T12 vertebrae), while M49.85 specifies the thoracolumbar junction. Use M49.85 when documentation or imaging identifies involvement at the T12–L1 transitional zone rather than the mid- or upper thoracic spine.

04Does M49.84 require a 7th character?

No. M-codes in the musculoskeletal chapter do not use 7th-character extensions. M49.84 is complete as a 5-character code and is billable as written.

05Can M49.84 be assigned for degenerative disc disease causing thoracic spondylopathy?

Not directly. M49.84 is reserved for spondylopathy as a manifestation of a disease classified elsewhere (e.g., metabolic, infectious, or neurological conditions). Primary degenerative disc disease codes to M51.- subcategories, not M49.84.

06What CPT codes most commonly pair with M49.84?

Thoracic spine imaging codes (72070–72080) and diagnostic E/M codes (99213–99215) are the most frequent pairings. Surgical intervention codes such as 22532–22534 (thoracic fusion) may apply when the underlying disease leads to structural instability requiring operative management.

07Does M49.84 cover kyphosis caused by osteoporosis?

Only if osteoporosis is the documented underlying cause of a thoracic spinal deformity and that cause is explicitly coded first. However, osteoporosis with vertebral fracture has its own code family (M80.-), which is often more precise. Review the clinical documentation to determine which code set best reflects the documented condition.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

01CDC ICD-10-CM Tabular List 2026 (FY2026, effective Oct 1, 2025)
02
icd10data.com
https://www.icd10data.com/ICD10CM/Codes/M00-M99/M45-M49/M49-/M49.84
03
aapc.com
https://www.aapc.com/codes/icd-10-codes/M49.84

Mira Scribe

Mira's AI scribe captures the underlying systemic diagnosis, the thoracic vertebral levels involved, imaging evidence of spinal deformity or structural change, and the treating physician's explicit linkage between the underlying disease and the spinal manifestation. That documentation locks in correct sequencing (underlying disease first), prevents downcoding to the unspecified site M49.80, and neutralizes an Excludes1 audit flag by confirming the cause is not on the exclusion list.

See how Mira captures M49.84 documentation