M05.662: Rheumatoid arthritis of left knee with involvement of other organs and systems

M05.662, rheumatoid arthritis of left knee with involvement of other organs and systems, is listed as a covered diagnosis in 11 Medicare billing and coding articles that apply to 85 HCPCS Level II codes, including J9312 (Injection, rituximab, 10 mg), Q5123 (Injection, rituximab-arrx, biosimilar, (riabni), 10 mg), Q5119 (Injection, rituximab-pvvr, biosimilar, (ruxience), 10 mg). 47 of these codes have a 2026 DMEPOS fee schedule amount; L1844 pays $1,865.51 to $2,436.24 depending on the state. The articles come from 5 Medicare contractors. A listed diagnosis supports medical necessity only; coverage still depends on the LCD's criteria and on documentation in the medical record.

HCPCS Level II codes with M05.662 as a covered diagnosis

CodeDescriptionMedicare coverageDMEPOS fee 2026 (state range)Articles listing it
J9312Injection, rituximab, 10 mgSpecial coverage instructions apply—3
Q5123Injection, rituximab-arrx, biosimilar, (riabni), 10 mgCarrier judgment—3
Q5119Injection, rituximab-pvvr, biosimilar, (ruxience), 10 mgCarrier judgment—3
Q5115Injection, rituximab-abbs, biosimilar, (truxima), 10 mgSpecial coverage instructions apply—3
J1745Injection, infliximab, excludes biosimilar, 10 mgSpecial coverage instructions apply—2
Q5104Injection, infliximab-abda, biosimilar, (renflexis), 10 mgSpecial coverage instructions apply—2
Q5103Injection, infliximab-dyyb, biosimilar, (inflectra), 10 mgSpecial coverage instructions apply—2
Q5121Injection, infliximab-axxq, biosimilar, (avsola), 10 mgCarrier judgment—2
J0881Injection, darbepoetin alfa, 1 microgram (non-esrd use)Special coverage instructions apply—1
J0885Injection, epoetin alfa, (for non-esrd use), 1000 unitsSpecial coverage instructions apply—1
Q5106Injection, epoetin alfa-epbx, biosimilar, (retacrit) (for non-esrd use), 1000 unitsSpecial coverage instructions apply—1
J0882Injection, darbepoetin alfa, 1 microgram (for esrd on dialysis)Special coverage instructions apply—1
J0888Injection, epoetin beta, 1 microgram, (for non esrd use)Special coverage instructions apply—1
Q5105Injection, epoetin alfa-epbx, biosimilar, (retacrit) (for esrd on dialysis), 100 unitsSpecial coverage instructions apply—1
J0887Injection, epoetin beta, 1 microgram, (for esrd on dialysis)Special coverage instructions apply—1
J0890Injection, peginesatide, 0.1 mg (for esrd on dialysis)Carrier judgment—1
Q4081Injection, epoetin alfa, 100 units (for esrd on dialysis)Special coverage instructions apply—1
J9260Injection, methotrexate sodium, 50 mgSpecial coverage instructions apply—1
J9215Injection, interferon, alfa-n3, (human leukocyte derived), 250,000 iuSpecial coverage instructions apply—1
J9311Injection, rituximab 10 mg and hyaluronidaseSpecial coverage instructions apply—1
J3590Unclassified biologicsCarrier judgment—1
G0278Iliac and/or femoral artery angiography, non-selective, bilateral or ipsilateral to catheter insertion, performed at the same time as cardiac catheterization and/or coronary angiography, includes positioning or placement of the catheter in the distal aorta or ipsilateral femoral or iliac artery, injection of dye, production of permanent images, and radiologic supervision and interpretation (list separately in addition to primary procedure)Carrier judgment—1
G0269Placement of occlusive device into either a venous or arterial access site, post surgical or interventional procedure (e.g., angioseal plug, vascular plug)Special coverage instructions apply—1
G0283Electrical stimulation (unattended), to one or more areas for indication(s) other than wound care, as part of a therapy plan of careCarrier judgment—2
A9585Injection, gadobutrol, 0.1 mlCarrier judgment—1

60 more codes are listed. See every code with payment by region in Caduvo.

Medicare policy articles listing M05.662

A diagnosis listed as covered in a billing and coding article supports medical necessity for the article's codes; it does not guarantee payment. Coverage depends on the LCD's criteria, the contractor's jurisdiction and documentation in the medical record.

Other M05 diagnoses (Rheumatoid arthritis with rheumatoid factor)

Frequently asked questions

Does Medicare cover M05.662 (Rheumatoid arthritis of left knee with involvement of…)?

Medicare covers items and services, not diagnoses. 11 Medicare billing and coding articles list M05.662 as a covered diagnosis for 85 HCPCS Level II codes: the diagnosis can support medical necessity for those codes, but payment still depends on the LCD's coverage criteria and the medical record.

Which HCPCS codes can be billed with ICD-10 M05.662?

The Level II codes from the policies most specific to this diagnosis are J9312 (Injection, rituximab, 10 mg, 3 articles); Q5123 (Injection, rituximab-arrx, biosimilar, (riabni), 10 mg, 3 articles); Q5119 (Injection, rituximab-pvvr, biosimilar, (ruxience), 10 mg, 3 articles); Q5115 (Injection, rituximab-abbs, biosimilar, (truxima), 10 mg, 3 articles); J1745 (Injection, infliximab, excludes biosimilar, 10 mg, 2 articles). Code choice depends on the item supplied; check each code's descriptor.

What does Medicare pay for equipment billed with M05.662?

Under the 2026 DMEPOS fee schedule (non-rural state fees): L1844 $1,865.51 to $2,436.24; L1860 $1,233.07 to $1,985.94; L1846 $1,283.72 to $1,960.17; L1834 $892.02 to $1,808.36. Medicare pays 80% of the allowed amount after the Part B deductible.

Which Medicare policy articles list M05.662?

A56795 (Billing and Coding: Erythropoiesis Stimulating Agents (ESAs)); A56432 (Billing and Coding: Infliximab); A55639 (Billing and Coding: Chemotherapy Agents for Non-Oncologic Conditions), and 8 more articles.

What is ICD-10-CM code M05.662?

M05.662 is the ICD-10-CM code for rheumatoid arthritis of left knee with involvement of other organs and systems, in category M05 (Rheumatoid arthritis with rheumatoid factor), chapter 13: Diseases of the musculoskeletal system and connective tissue.

Next steps

Sources: CMS Medicare Coverage Database billing and coding articles (covered ICD-10 code lists and HCPCS links); ICD-10-CM FY2026; CMS HCPCS Level II release October 2026; CMS DMEPOS fee schedule 2026 (non-rural state fees). Not billing or legal advice.

Chapter 13: Diseases of the musculoskeletal system and connective tissue · All diagnoses · HCPCS lookup