Dr. Gregory Duff, M.D.

Orthopedic Surgery
25 procedures 2 hospitals Silverdale, WA
Latest available Medicare data — updated April 2026
Growing Volume

Contact & Location

Phone: 360-698-6630
Practice phone listed in the NPI registry
4409 Nw Anderson Hill Rd
Silverdale, WA 98383
NPI: 1952374290
Credentials: M.D.
Active Medicare provider (NPI verified)
20 years of practice experience
Licensed M.D.
Licensed surgical specialist
Board-certified orthopedic surgeon
Contact information available
Find Practice on Google Maps
Shoulder replacement recovery kit Slings, cold therapy, and adaptive clothing for recovery
National Comparison by Procedure
Shoulder 25 vs 29 avg (2,213 surgeons)

Dr. Gregory Duff is a board-certified orthopedic surgeon practicing in Silverdale, Washington. A Medicare provider since 2006, Dr. Duff has performed 25 Medicare-verified shoulder replacements, ranking #24 in Washington.

In Washington, Dr. Duff performs near average in shoulder (25 vs 28 avg).

Dr. Duff's Medicare data shows a focused shoulder replacement practice with 25 verified procedures. Surgeons who concentrate on a single procedure type often develop deep procedural expertise, though total practice volume may include additional procedures not captured in Medicare fee-for-service data.

Silverdale is home to 6 orthopedic surgeons in the current Medicare dataset. Patients in the Silverdale area can compare surgeon volume and procedure specialization to find the right fit for their joint replacement needs.

Medicare records for Dr. Duff extend back to 2020, covering 5 years of data. Over that period, recorded procedure volume increased from 12 to 25 in the most recent data, a 108% increase. This sustained growth reflects an expanding joint replacement practice.

Among 2,213 shoulder replacement surgeons tracked nationally, Dr. Duff's 25 verified procedures is near the national average of 29.

Verified Medicare Cases

Shoulder Replacement
25 verified cases
#24 in Washington
Estimated total: 70 – 80 procedures (all insurers)
Based on Medicare FFS representing 33–37% of national joint replacement volume
How is this estimated?

Medicare Part B fee-for-service claims represent approximately 33–37% of all joint replacements performed nationally (source: CMS data, AJRR). This range estimates the surgeon's total practice volume across all payers. The verified Medicare count above is the definitive, audited figure.

How Dr. Duff Compares

Procedure volume compared to the Washington state average.

Shoulder Average
25 Avg: 28
Dr. Duff Washington Average

Volume Trend Analysis

Dr. Duff's Medicare-recorded procedure volume has trended upward over 5 years, increasing 108% from 12 procedures in 2020 to 25 in the most recent data.

Years of Data 5
2024 Volume 25
Peak Volume 25 (2024)
Trend Growing

Hospital Affiliations & Quality

H
St Michael Medical Center
4/5
Silverdale, WA
Similar to national avg
H
Olympic Medical Center
3/5
Port Angeles, WA
Low case volume

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 Shoulder Replacement

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

Shoulder Replacement Recovery Overview

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

Week 1-3 Arm in a sling for protection. Gentle pendulum exercises under therapist guidance. Focus on pain management and wound care.
Week 4-6 Gradual sling weaning. Begin passive and active-assisted range-of-motion exercises. Light daily activities resume.
Week 7-12 Active range-of-motion exercises. Light strengthening begins. Most patients can drive and perform desk work.
Month 4-6 Progressive strengthening continues. Return to most activities. Full recovery may take 6-12 months for complete shoulder strength.

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

Frequently Asked Questions About Dr. Duff

How does Dr. Duff's procedure volume compare to other Washington surgeons?

Dr. Duff has performed 25 Medicare-verified joint replacement procedures. The Washington average is 59 procedures per surgeon. Medicare data captures roughly one-third of all joint replacements, so total volume may be higher. Dr. Duff ranks #148 out of 198 orthopedic surgeons in Washington.

What types of joint replacement does Dr. Duff perform?

Dr. Duff's reported Medicare volume is focused on shoulder replacement, with 25 verified procedures. Some surgeons choose to concentrate on a single joint type to build deep procedural expertise.

Are there other orthopedic surgeons near Dr. Duff in Silverdale?

Yes. There are 6 orthopedic surgeons in Silverdale 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 Washington surgeons.

What does the Medicare data for Dr. Duff represent?

The procedure counts shown are based on the most recent Medicare Part B fee-for-service claims data, published by the Centers for Medicare and Medicaid Services (CMS). This captures approximately 33–37% of all joint replacements performed nationally. Dr. Duff's total practice volume — including private insurance and Medicare Advantage patients — is likely higher than the 25 procedures shown here.

Has Dr. Duff's procedure volume changed over time?

Yes. Dr. Duff's Medicare-recorded volume has increased from 12 procedures in 2020 to 25 in the most recent data, a 108% increase over 5 years. This upward trend suggests an expanding joint replacement practice. Peak volume was 25 procedures in 2024.

Which hospitals is Dr. Duff affiliated with?

According to CMS facility affiliation data, Dr. Duff is affiliated with St Michael Medical Center, Olympic Medical Center.

How does Dr. Duff compare to other orthopedic surgeons in Silverdale?

Among the 6 orthopedic surgeons in Silverdale, Dr. Duff ranks #6 by total Medicare procedure volume. The highest-volume surgeon in Silverdale has 182 verified Medicare procedures.

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

St Michael Medical Center (4 out of 5 CMS stars, hip/knee complication rate similar to national average); Olympic Medical Center (3 out of 5 CMS stars, insufficient case volume for complication rate comparison). These are hospital-level quality metrics from CMS Hospital Compare and do not reflect individual surgeon outcomes.

Other Orthopedic Surgeons in Silverdale, Washington

Dr. Duff's 25 Medicare procedures are below the Silverdale average of 80. The table below compares verified procedure volumes for orthopedic surgeons practicing in Silverdale.

SurgeonProceduresSpecialties
Dr. Omar Abdul-Hadi 182 Hip, Knee
Dr. Erin Moyer 98 Hip, Knee
Dr. Bradley Watters 72 Hip, Knee
Dr. Dawson Brown 64 Shoulder
Dr. Christopher Rankin 40 Shoulder

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. Gregory Duff, M.D. -- Orthopedic Surgeon Profile. Retrieved from https://orthoprocedures.com/surgeons/wa/dr-gregory-duff-silverdale.html

Link: https://orthoprocedures.com/surgeons/wa/dr-gregory-duff-silverdale.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.