Gregory J. Adamson, M.D.
Sports Medicine (Orthopaedic Surgery) Physician · Pasadena, CA
Gregory J. Adamson, M.D. is a sports medicine (orthopaedic surgery) physician with a practice address in Pasadena, California, and NPI 1972590610, issued on Sep 27, 2005. Check the license (California G58923, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Gregory J. Adamson
- Credential
- M.D.
- Primary taxonomy
- Sports Medicine (Orthopaedic Surgery) Physician 207XX0005X
- License number
- G58923 CA
Self-reported in NPPES; status is on the state search - Practice location
- 800 S Raymond Ave, Pasadena, CA 91105
- Phone
- (626) 795-8051
- Enumerated
- Sep 27, 2005
- Record last updated
- Mar 4, 2024
- Fax
- (626) 795-0356
- Medicare enrollment
- Enrolled (PECOS I20040420001782); accepts Medicare assignment
- Medical or professional school
- University Of Southern California Keck School Of Medicine, 1981
- Entity
- Type 1 · individual
8 nearest sports medicine (orthopaedic surgery) physician records → All 384 in California → Look up another NPI →
Also registered at 800 S Raymond Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Lea Armendariz, PTPhysical Therapist1427327147
- Roy Ashford, M.D.Orthopaedic Surgery of the Spine Physician1588646368
- Julie Cann, PA-CPhysician Assistant1972734929
- William Costigan, M.D.Orthopaedic Surgery of the Spine Physician1821084641
- Richard Diehl, M.D.Orthopaedic Surgery Physician1417943127
- Todd Dietrick, M.D.Adult Reconstructive Orthopaedic Surgery Physician1619963444
Verify Gregory J. Adamson in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G58923Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
75% fewer Medicare Part D claims than the average sports medicine (orthopaedic surgery) physician in 2024
73 Medicare Part D claims for 47 beneficiaries, against an average of 288 among the 2,562 providers of this specialty who prescribed in Part D. Brand-name drugs were 0% of claims. 50 claims were for opioids.
Most prescribed
- Hydrocodone-Acetaminophen34 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
The practice group's MIPS final score for 2023 (Medicare payment program): 76.6 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
Bills Medicare through 2 group practices
- Cedars-Sinai Medical Care FoundationPasadena, CA
- David B. HammerTempleton, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Gregory J. Adamson among 384 sports medicine (orthopaedic surgery) physician records in California
Gregory J. Adamson, M.D. is one of 384 sports medicine (orthopaedic surgery) physician records with a practice address in California. 88% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 93% newer
- In a Medicare fileYes · 88% of these records are
- In the CMS Doctors and Clinicians fileYes · 76% of these records are
- Graduated1981 · median 2003 among the 293 with a school on file
- Record last updated2024 · 51% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207XX0005X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Sports Medicine (Orthopaedic Surgery) Physician providers in California
There are 384 sports medicine (orthopaedic surgery) physician records in California.
All 384 in California → Every provider in Pasadena → Sports Medicine (Orthopaedic Surgery) Physician nationwide →
The 8 sports medicine (orthopaedic surgery) physician records with the nearest ZIP codes
- Michael Fraipont, MDPasadena, CA 911051164418893
- Charles Long, MDPasadena, CA 911051780035220
- Aaron Gipsman, M.D.Pasadena, CA 911061669854923
- Gregory Northrop, MDPasadena, CA 911071962404582
- Swapnil Shah, MDPasadena, CA 911071427283878
- Raffy Mirzayan, MDLa Canada, CA 910111588731467
- Rishi Garg, M.D.Arcadia, CA 910071164642583
- Gregory Heinen, MDArcadia, CA 910071962447961
Common questions
What is Gregory J. Adamson, M.D.'s NPI number?
Gregory J. Adamson, M.D.'s National Provider Identifier (NPI) is 1972590610, issued on Sep 27, 2005. An NPI identifies a provider in billing; it is not a license.
Where is Gregory J. Adamson, M.D. located?
The NPPES record lists a practice address at 800 S Raymond Ave, Pasadena, CA, 91105. Phone: (626) 795-8051. Providers update this record themselves, so call before visiting.
How can I verify Gregory J. Adamson, M.D.'s license?
NPPES lists California license number G58923, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Gregory J. Adamson, M.D. prescribe under Medicare Part D?
In 2024, Gregory J. Adamson, M.D. had 73 Medicare Part D claims for 47 beneficiaries; the average among sports medicine (orthopaedic surgery) physician prescribers was 288. Part D covers Medicare prescriptions only.
What is Gregory J. Adamson, M.D.'s MIPS final score?
The 2023 MIPS final score is 76.6 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.