Dr. Robert Kay, MD

Orthopedic Surgery
100 procedures 1 hospital Boston, MA

Contact & Location

617-724-8801
Phone: 617-724-8801
Practice phone listed in the NPI registry
55 Fruit St
Boston, MA 02114
Current practice address per the CMS NPPES registry (self-reported to the registry, last updated October 2024). Registry checked August 2026.
Other locations registered to this NPI:
1000 W Carson St
Torrance, CA 90502
Additional practice sites listed in the surgeon's own CMS NPPES registry entry. The registry does not record which site a surgeon primarily works from, so call ahead to confirm where an appointment takes place.
NPI: 1912495656
Credentials: MD
Active Medicare provider (NPI verified)
8 years of practice experience
Licensed MD
Licensed surgical specialist
Board-certified orthopedic surgeon
Contact information available
Find Practice on Google Maps
National Comparison by Procedure
Hip 39 vs 36 national avg (4,542 surgeons)
Knee 61 vs 45 national avg (6,612 surgeons)

Dr. Kay performs more knee replacement procedures than 71% of orthopedic surgeons in Massachusetts, based on 2024 Medicare claims volume.Derived from the state ranking shown on this page: #45 of 160 ranked knee surgeons in Massachusetts.

About Dr. Kay

Dr. Robert Kay is a board-certified orthopedic surgeon practicing in Boston, Massachusetts. A Medicare provider since 2018, Dr. Kay performed 61 Medicare-verified knee replacements (#45 in Massachusetts) and 39 hip replacements in the latest annual CMS data, for a combined total of 100 procedures.

In Massachusetts, Dr. Kay performs above the state average in knee (61 vs 50), near the state average in hip (39 vs 44).

Dr. Kay's reported Medicare volume is split between knee replacements (61 cases) and hip replacements (39 cases).

Boston is home to 50 orthopedic surgeons in the current Medicare dataset. Patients in the Boston area can compare surgeon volume and procedure specialization to find the right fit for their joint replacement needs.

Dr. Kay first appears in the Medicare dataset in 2023. With 2 years of recorded data, the longitudinal trend is still developing.

Among 6,612 knee replacement surgeons tracked nationally, Dr. Kay's 61 verified procedures is above the national average of 45.

Verified Medicare Cases

Knee Replacement
61 verified cases
#45 in Massachusetts
Hip Replacement
39 verified cases
#58 in Massachusetts
Estimated 2024 total: 340 – 420 procedures (all insurers)
Medicare fee-for-service share of national volume in 2024: 23% to 28% for knee replacement, 25% to 33% for hip replacement
How is this estimated?

Medicare Part B fee-for-service claims are one payer stream among several, and the share they represent differs by procedure. In 2024 it was 23% to 28% for knee replacement, 25% to 33% for hip replacement. Each verified count above is divided by its own procedure's range, and the results are added, to estimate total practice volume across all payers. The verified Medicare count is the definitive, audited figure; this is a range derived from published national volume projections, not a measurement, and an individual practice can sit well outside it: how these ranges are derived, and their sources.

How Dr. Kay Compares

Procedure volume compared to the Massachusetts state average.

Hip Average
39 Avg: 44
Knee High
61 Avg: 50
Dr. Kay Massachusetts Average

Volume Trend Analysis

Dr. Kay has 2 years of Medicare procedure data beginning in 2023. Additional years of data will provide a clearer picture of volume trends.

Years of Data 2
2024 Volume 100
Peak Volume 100 (2024)
Trend Developing

Hospital Affiliations & Quality

H
Kaiser Foundation Hospital Fontana
3/5
Fontana, CA

Quality ratings and complication rates are hospital-level metrics from CMS Hospital Compare and do not reflect individual surgeon performance. Star ratings updated quarterly. Complication data covers a rolling 3-year period.

Patient Resources: Preparing for Knee Replacement

If you are considering knee replacement surgery, these evidence-based guides can help you prepare and recover:

Knee Replacement Recovery Overview

Recovery timelines vary by patient, but here is a general overview of what to expect after knee replacement surgery:

Week 1-2 Walking with assistive device. Knee bending exercises begin immediately. Ice therapy and elevation for swelling control.
Week 3-6 Increased range of motion (target 90 degrees). Walking longer distances. Physical therapy intensifies with strengthening exercises.
Week 7-12 Most patients walk without assistive devices. Resume driving and desk work. Continue PT for strength and flexibility.
Month 4-6 Near-full recovery. Resume most recreational activities. Some swelling and stiffness may persist but continues improving.

Individual recovery varies based on overall health, age, and adherence to physical therapy. View full knee replacement recovery guide and product recommendations

Frequently Asked Questions About Dr. Kay

How does Dr. Kay's procedure volume compare to other Massachusetts surgeons?

Dr. Kay has performed 100 Medicare-verified joint replacement procedures. This is in line with the Massachusetts average of 74 procedures per surgeon. Dr. Kay ranks #57 out of 203 orthopedic surgeons in Massachusetts.

What types of joint replacement does Dr. Kay perform?

Dr. Kay's Medicare data shows procedures in knee replacement (61 cases) and hip replacement (39 cases).

Are there other orthopedic surgeons near Dr. Kay in Boston?

Yes. There are 50 orthopedic surgeons in Boston in the current Medicare dataset. Patients can compare procedure volumes and specializations to choose the surgeon who best fits their needs. Use the state page to view all Massachusetts surgeons.

What does the Medicare data for Dr. Kay represent?

The procedure counts shown are based on 2024 Medicare Part B fee-for-service claims data, published by the Centers for Medicare and Medicaid Services (CMS). Medicare fee-for-service is only one payer stream, and the share of national volume it represents differs by procedure. In 2024 the share was 23% to 28% for knee replacement, 25% to 33% for hip replacement, which puts Dr. Kay's total volume across all insurers at roughly 340 to 420 procedures against the 100 verified here. Those shares are derived from published national volume projections rather than quoted from a single publication, and they are estimates with real uncertainty. The OrthoProcedures methodology page shows the full derivation, the sources, and the limits at orthoprocedures.com/data-methodology.html.

Does Dr. Kay perform more than one type of joint replacement?

Yes. Dr. Kay's Medicare data shows procedures in knee replacement (61 cases), hip replacement (39 cases). Surgeons who perform multiple joint replacement types maintain broad technical skills across different anatomical joints.

Which hospitals is Dr. Kay affiliated with?

According to CMS facility affiliation data, Dr. Kay is affiliated with Kaiser Foundation Hospital Fontana. Dr. Kay maintains hospital privileges across state lines, indicating a practice that serves patients in multiple states.

How does Dr. Kay compare to other orthopedic surgeons in Boston?

Among the 50 orthopedic surgeons in Boston, Dr. Kay ranks #21 by total Medicare procedure volume. The highest-volume surgeon in Boston has 305 verified Medicare procedures.

What are the quality ratings for hospitals where Dr. Kay practices?

Kaiser Foundation Hospital Fontana (3 out of 5 CMS stars). These are hospital-level quality metrics from CMS Hospital Compare and do not reflect individual surgeon outcomes.

Other Orthopedic Surgeons in Boston, Massachusetts

Dr. Kay's 100 Medicare procedures are below the Boston average of 194. The table below compares verified procedure volumes for orthopedic surgeons practicing in Boston.

SurgeonProceduresSpecialties
Dr. Carl Talmo 305 Hip, Knee
Dr. Young-Min Kwon 235 Hip, Knee
Dr. James Bono 204 Hip, Knee
Dr. Nicholas Pagani 178 Hip, Knee
Dr. Eric Smith 170 Hip, Knee
Dr. Dennis Burke 169 Hip, Knee

Patient Resources & Verification

Research reviews, verify credentials, and check official quality data through these trusted sources:

Medicare Care Compare and NPI Registry are official U.S. government sources. Google reviews reflect user-submitted feedback. OrthoProcedures.com does not verify the accuracy of third-party review content.

Cite This Data

APA: OrthoProcedures. (2026). Dr. Robert Kay, MD -- Orthopedic Surgeon Profile. Retrieved from https://orthoprocedures.com/surgeons/ma/dr-robert-kay-boston.html

Link: https://orthoprocedures.com/surgeons/ma/dr-robert-kay-boston.html

Data source: CMS Medicare Part B Provider Utilization & Payment Data. Full methodology | Open Data API

Important: Rankings are based solely on Medicare procedure volume and do not reflect quality of care, patient outcomes, or procedures covered by private insurance. This data represents approximately one-third to 40% of all joint replacement procedures nationwide. Always consult with healthcare providers to make informed decisions about your care.