Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Ellen Tsay

Individual provider Orthopaedic Surgery Physician · NPI 1194354951

Ellen Tsay practises Orthopedic Surgery in Vacaville, California. Qualified in 2020, 6 years ago. Practices with Reconstructive Orthopaedic Associates II LLC, a 275-clinician group and accepts Medicare assignment. Licensed in New Jersey and Pennsylvania.

Years since qualifying
6
Licensed in
NJ, PA
In the registry since
2020
Specialties on file
2
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Practice location Address checks out

1 Quality Dr
Vacaville, CA 95688-9494
Phone: (707) 651-5502
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Orthopaedic Surgery Physician (primary) Taxonomy 207X00000X · Licence MD487615 (PA)
Orthopaedic Surgery Physician Taxonomy 207X00000X · Licence 25MA12498400 (NJ)

Record details

NPI number1194354951
Entity typeIndividual (Type 1)
GenderFemale
Sole proprietorYes
NPI enumeratedApril 3, 2020
Last updated in NPPESSeptember 22, 2026
Certification dateSeptember 22, 2026

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyORTHOPEDIC SURGERY
Medical schoolOTHER
Graduated 2020 (6 years in practice)
Group practice Reconstructive Orthopaedic Associates Ii Llc — 275 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations2 on file with Medicare

Procedures

From CMS Care Compare, which counts the procedures a clinician billed to Original Medicare and Medicare Advantage over a recent 12-month period. CMS reports a fixed list of common procedures, so this is not everything the clinician does. Counts of 10 or fewer are given as a range, because CMS withholds small numbers.

Hip replacement 60 times · 91st percentile
Knee replacement 65 times · 85th percentile

The percentile compares how often this clinician performed the procedure with other clinicians who performed it, as CMS calculates it. It measures volume, not outcomes or skill.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Grant $3,125 1 payment · funding for a project or programme, not a fee for the clinician’s time
Travel and Lodging $1,690 5 payments · travel or lodging paid or reimbursed, such as to attend a conference
Food and Beverage $1,186 15 payments · a meal or drink at a meeting or visit, not a fee
Education $77 1 payment · educational material or training, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician. Those with a page here are linked.

Colleagues at Reconstructive Orthopaedic Associates II LLC

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 275 clinicians in the practice; 12 are shown here.

Other providers in Vacaville