ICD-10-CM M45 is the diagnosis code for Ankylosing spondylitis. This code falls under the section "Spondylopathies" within Chapter 13 — Diseases of the musculoskeletal system and connective tissue (M00-M99). It is a non-billable/non-specific ICD-10-CM code that should not be used for reimbursement. A more specific sub-code is required for billing. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.
The following conditions should never be coded at the same time as M45. They are mutually exclusive:
The following conditions are not included in M45. If the patient has both, code each condition separately:
Understanding where M45 sits in the ICD-10-CM classification helps ensure proper coding:
No, M45 is a non-billable/non-specific code. You should use a more specific sub-code for billing and reimbursement.
M45 is the ICD-10-CM diagnosis code for "Ankylosing spondylitis". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.
M45 is located in Section M45-M49 — "Spondylopathies" within Chapter 13 of the ICD-10-CM Tabular List.
M45 has 11 sub-code(s) that provide more specific detail: M45.0, M45.1, M45.2, M45.3, M45.4 and more.
Use M45 when the patients documented diagnosis matches "Ankylosing spondylitis" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.
The ICD-10-CM code for Ankylosing spondylitis is M45.
No, M45 is non-billable. Use a more specific sub-code for primary diagnosis billing.
M45 is in Chapter 13 of the ICD-10-CM Tabular List.
Type 1 Excludes for M45 include: arthropathy in Reiter's disease (M02.3-); juvenile (ankylosing) spondylitis (M08.1).
Yes, M45 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.