Quick answers
- Does John R. Greensfelder accept Medicare assignment?
- Yes. Medicare's clinician data says John R. Greensfelder accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does John R. Greensfelder see?
- In 2024, CMS data shows 78 Original Medicare patients and 867 services for John R. Greensfelder. This counts Original Medicare only and measures volume, not quality.
- What is John R. Greensfelder's NPI number?
- 1871637207. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for John R. Greensfelder, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 78 |
|---|---|
| Services billed to Medicare | 867 |
| Different services or procedures | 2 |
| Participating Medicare provider | Yes |
| Average age of these patients | 73 |
Most frequent services
- Chiropractic manipulative treatment, 3-4 spinal regions (98941)824 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High cholesterol73%
- High blood pressure60%
- Arthritis45%
- Ischemic heart disease23%
- Diabetes22%
- Anxiety14%
Practice locations
Addresses where John R. Greensfelder is enrolled with Medicare (CMS data updated October 2, 2026).
- 1350 Blair Dr, Suite HhOdenton, MD 21113 (410) 674‑8605
Specialties
- Chiropracticprimary
Other chiropractors in Maryland
Clinicians with the same Medicare primary specialty in Maryland — not a recommendation.
Clinician information
| Credential | DC |
|---|---|
| Chiropractic college | Los Angeles College Of Chiropractic |
| Graduation year | 1996 (30 years since chiropractic college) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1871637207 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians