ICD-10-CM 2027
ICD-10 code for lumbosacral region flatback syndrome
From the official ICD-10-CM alphabetic index entry “Flatback syndrome › lumbosacral region”. Page updated September 29, 2026.
About coding lumbosacral region flatback syndrome
The ICD-10-CM code for lumbosacral region flatback syndrome is M40.37 (Flatback syndrome, lumbosacral region).
Within M40.3 (Flatback syndrome), M40.37 is specifically for Flatback syndrome, lumbosacral region. Related codes cover site unspecified (M40.30), thoracolumbar region (M40.35) and lumbar region (M40.36).
Code first: underlying disease.
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
Common questions about lumbosacral region flatback syndrome ICD-10 codes
What is the ICD-10 code for lumbosacral region flatback syndrome?
- M40.37 — Flatback syndrome, lumbosacral region.
Is M40.37 billable?
- Yes. M40.37 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can M40.37 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict M40.37 as a principal diagnosis.
Is M40.37 a CC or MCC?
- No. M40.37 is neither a CC nor an MCC under MS-DRG v44.0.