551 MS-DRG: MEDICAL BACK PROBLEMS WITH MCC
MS-DRG 551 groups Medicare inpatient hospital stays for: MEDICAL BACK PROBLEMS WITH MCC. This is a medical MS-DRG. It falls under MDC 08 (Diseases and Disorders of the Musculoskeletal System and Connective Tissue).
Payment & Classification Data
Official CMS values from the FY2027 IPPS Final Rule Table 5.
| Major Diagnostic Category | MDC 08 — Diseases and Disorders of the Musculoskeletal System and Connective Tissue |
| DRG Type | Medical |
| Severity Level | MCC |
| Relative Weight | 1.6358 |
| Relative Weight (10% Cap Applied) | 1.6358 |
| Geometric Mean Length of Stay | 4.4 days |
| Arithmetic Mean Length of Stay | 5.7 days |
| Post-Acute Transfer DRG | Yes |
| Special Pay Transfer DRG | No |
Defining Codes (FY2027)
1,170 diagnosis codes can drive assignment here: M25.78, M40.00, M40.03, M40.04, M40.05, M40.10, M40.12, M40.13, M40.14, M40.15, M40.202, M40.203 and 1,158 more.
From the CMS MS-DRG Definitions Manual (Appendices B and E). Assignment also depends on severity, discharge status and the rest of the claim.
Contextual Map
Every relationship of 551 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Major Diagnostic Category
- MDC 08 — Diseases and Disorders of the Musculoskeletal System and Connective Tissue[MDC]— CMS MS-DRG Definitions Manual · FY2027
Defining diagnoses (1170)
- M25.78 — Osteophyte, vertebrae[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- M40.00 — Postural kyphosis, site unspecified[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- M40.03 — Postural kyphosis, cervicothoracic region[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- M40.04 — Postural kyphosis, thoracic region[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- M40.05 — Postural kyphosis, thoracolumbar region[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- M40.10 — Other secondary kyphosis, site unspecified[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- M40.12 — Other secondary kyphosis, cervical region[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- M40.13 — Other secondary kyphosis, cervicothoracic region[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- and 1162 more
DRG family
- DRG 552 — MEDICAL BACK PROBLEMS WITHOUT MCC[DRG family]: “MEDICAL BACK PROBLEMS WITHOUT MCC — same CMS DRG family (551-552), split by severity.”— CMS MS-DRG Definitions Manual (DRG family 551-552) · FY2027
Read from: CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v44. All data sources · How to read the labels