MS-DRG 550: SEPTIC ARTHRITIS WITHOUT CC/MCC
MS-DRG 550 is septic arthritis without cc/mcc, in MDC 08 (a medical DRG), at the without-CC/MCC level. Its FY2027 relative weight is 0.8591, so a case here pays less than the average Medicare inpatient stay (weight 1.0), with a geometric mean length of stay of 2.80 days. 155 ICD-10-CM principal diagnoses group into MS-DRGs 548–550 under the CMS definitions manual; the most-searched are listed below.
FY2027 payment factors
- Relative weight
- 0.8591
- Geometric mean LOS
- 2.80
- Arithmetic mean LOS
- 3.50
- Post-acute transfer
- No
Principal diagnoses that group to MS-DRGs 548–550
From the CMS MS-DRG definitions manual’s principal-diagnosis index: 155 ICD-10-CM codes route here, and the CC/MCC status of the secondary diagnoses decides which of 548–550 the case lands in. The 24 most-searched:
- M00.9Pyogenic arthritis, unspecified
- A02.23Salmonella arthritis
- A18.02Tuberculous arthritis of other joints
- A18.09Other musculoskeletal tuberculosis
- A39.83Meningococcal arthritis
- A39.84Postmeningococcal arthritis
- A54.40Gonococcal infection of musculoskeletal system, unspecified
- A54.42Gonococcal arthritis
- A54.43Gonococcal osteomyelitis
- A54.49Gonococcal infection of other musculoskeletal tissue
- A66.6Bone and joint lesions of yaws
- M00.00Staphylococcal arthritis, unspecified joint
- M00.011Staphylococcal arthritis, right shoulder
- M00.012Staphylococcal arthritis, left shoulder
- M00.019Staphylococcal arthritis, unspecified shoulder
- M00.021Staphylococcal arthritis, right elbow
- M00.022Staphylococcal arthritis, left elbow
- M00.029Staphylococcal arthritis, unspecified elbow
- M00.031Staphylococcal arthritis, right wrist
- M00.032Staphylococcal arthritis, left wrist
- M00.039Staphylococcal arthritis, unspecified wrist
- M00.041Staphylococcal arthritis, right hand
- M00.042Staphylococcal arthritis, left hand
- M00.049Staphylococcal arthritis, unspecified hand
131 more codes group here. Open any code above for its full hierarchy, or check a whole claim in the free DRG calculator.
The severity splits
Same base DRG, split by whether a secondary diagnosis is a CC or MCC. The last column is the weight change from MS-DRG 550.
| 548 | SEPTIC ARTHRITIS WITH MCC | 1.9519 | +1.0928 |
| 549 | SEPTIC ARTHRITIS WITH CC | 1.1435 | +0.2844 |
| 550 | SEPTIC ARTHRITIS WITHOUT CC/MCC | 0.8591 |
All FY2027 MS-DRGs · MDC 08