M99.18 — Subluxation complex (vertebral) of rib cage

BillableCC

Is M99.18 billable?

Yes — M99.18 is billable for FY2027. M99.18 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. M99.18 may be submitted for encounters from October 1, 2026 through September 30, 2027.

M99.18 at a glance

Code	M99.18
Description	Subluxation complex (vertebral) of rib cage
Billable	Yes
Code set	ICD-10-CM FY2027
Valid for encounters	October 1, 2026 – September 30, 2027

Which MS-DRGs does M99.18 group to?

M99.18 sits in MDC 04 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.

183Major Chest Trauma with MCCmedical
184Major Chest Trauma with CCmedical
185Major Chest Trauma without CC/MCCmedical

As a secondary diagnosis, M99.18 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG. It also carries Hospital-Acquired Condition category 05.

How is M99.18 listed in the Alphabetic Index?

These are the routes through the Alphabetic Index that lead to M99.18. They show the wording a clinician may have documented, which often differs from the Tabular description.

Complex › subluxation › costochondral
Complex › subluxation › costovertebral
Complex › subluxation › rib cage
Complex › subluxation › sternochondral

Excludes2 — not included here — inherited from Chapter 13

The conditions below are not part of M99.18, but a patient may have both at the same time. When documentation supports it, M99.18 and the excluded code may both be reported.

arthropathic psoriasis (L40.5-)
certain conditions originating in the perinatal period (P04-P96)
certain infectious and parasitic diseases (A00-B99)
compartment syndrome (traumatic) (T79.A-)
complications of pregnancy, childbirth and the puerperium (O00-O9A)
congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
endocrine, nutritional and metabolic diseases (E00-E88)
injury, poisoning and certain other consequences of external causes (S00-T88)
neoplasms (C00-D49)
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

How long has M99.18 existed?

M99.18 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.

Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.