ICD-10 · PDGM grouping
M40 Kyphosis and lordosis
All 31 codes in the M40 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
Codes in family
31
Can lead a claim
0
Cannot lead a claim
31
What CMS assigns to M40
None of the 31 codes is assigned a clinical group. None of the 31 is assigned a comorbidity subgroup. None can lead a claim. CMS attaches a code-first note to all 31.
Code first
CMS grouper convention 12, on all 31 codes. Code first:
- underlying disease
Every code in M40
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| M40.0 Postural kyphosis | ||||
| M40.00 | Postural kyphosis, site unspecified | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.03 | Postural kyphosis, cervicothoracic region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.04 | Postural kyphosis, thoracic region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.05 | Postural kyphosis, thoracolumbar region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.1 Other secondary kyphosis | ||||
| M40.10 | Other secondary kyphosis, site unspecified | Cannot lead a claimUnacceptable principal diagnosis, code is not reportable as principal diagnosis | None | None |
| M40.12 | Other secondary kyphosis, cervical region | Cannot lead a claimUnacceptable principal diagnosis, code is not reportable as principal diagnosis | None | None |
| M40.13 | Other secondary kyphosis, cervicothoracic region | Cannot lead a claimUnacceptable principal diagnosis, code is not reportable as principal diagnosis | None | None |
| M40.14 | Other secondary kyphosis, thoracic region | Cannot lead a claimUnacceptable principal diagnosis, code is not reportable as principal diagnosis | None | None |
| M40.15 | Other secondary kyphosis, thoracolumbar region | Cannot lead a claimUnacceptable principal diagnosis, code is not reportable as principal diagnosis | None | None |
| M40.2 Other and unspecified kyphosis | ||||
| M40.20 Unspecified kyphosis | ||||
| M40.202 | Unspecified kyphosis, cervical region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.203 | Unspecified kyphosis, cervicothoracic region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.204 | Unspecified kyphosis, thoracic region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.205 | Unspecified kyphosis, thoracolumbar region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.209 | Unspecified kyphosis, site unspecified | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.29 Other kyphosis | ||||
| M40.292 | Other kyphosis, cervical region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.293 | Other kyphosis, cervicothoracic region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.294 | Other kyphosis, thoracic region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.295 | Other kyphosis, thoracolumbar region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.299 | Other kyphosis, site unspecified | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.3 Flatback syndrome | ||||
| M40.30 | Flatback syndrome, site unspecified | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.35 | Flatback syndrome, thoracolumbar region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.36 | Flatback syndrome, lumbar region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.37 | Flatback syndrome, lumbosacral region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.4 Postural lordosis | ||||
| M40.40 | Postural lordosis, site unspecified | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.45 | Postural lordosis, thoracolumbar region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.46 | Postural lordosis, lumbar region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.47 | Postural lordosis, lumbosacral region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.5 Lordosis, unspecified | ||||
| M40.50 | Lordosis, unspecified, site unspecified | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.55 | Lordosis, unspecified, thoracolumbar region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.56 | Lordosis, unspecified, lumbar region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M40.57 | Lordosis, unspecified, lumbosacral region | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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