M40.55 Lordosis, unspecified, thoracolumbar region

Billable ICD-10-CM code, FY2026.

Applies from M40 Kyphosis and lordosis

Excludes1 (never code together)

• congenital kyphosis and lordosis (Q76.4)
• kyphoscoliosis (M41.-)
• postprocedural kyphosis and lordosis (M96.-)

Code first

• underlying disease

MS-DRG index

Defines the logic of DRG(s) 456-458 in MDC 08.

Approximate ICD-9-CM (GEMs)

• 737.29 Other lordosis (acquired) (approximate)
• 737.42 Lordosis associated with other conditions (approximate)

Code annotations containing back-references to M40.55

Back-references to M40

• Type 2 Excludes: M43.8 Other specified deforming dorsopathies ("kyphosis and lordosis (M40.-)")
• Type 2 Excludes: M95 Other acquired deformities of musculoskeletal system and connective tissue ("deforming dorsopathies (M40-M43)")

Diagnosis Index entries for M40.55

• Lordosis › thoracolumbar region

Nearby codes

• M40.45 Postural lordosis, thoracolumbar region
• M40.46 Postural lordosis, lumbar region
• M40.47 Postural lordosis, lumbosacral region
• M40.5 Lordosis, unspecified
• M40.50 Lordosis, unspecified, site unspecified
• M40.55 Lordosis, unspecified, thoracolumbar region (this code)
• M40.56 Lordosis, unspecified, lumbar region
• M40.57 Lordosis, unspecified, lumbosacral region