Dr. Scott Zehnder, M.D.
Contact & Location
314-983-4700
Saint Louis, MO 63141
Dr. Zehnder performs more knee replacement procedures than 45% of orthopedic surgeons in Missouri, based on 2024 Medicare claims volume.Derived from the state ranking shown on this page: #90 of 166 ranked knee surgeons in Missouri.
About Dr. Zehnder
Practice. Dr. Scott Zehnder is a board-certified orthopedic surgeon practicing in Saint Louis, Missouri. The latest annual CMS data records 27 knee replacements and 13 hip replacements, 40 procedures in all. That is #90 in Missouri for knee replacement. A Medicare provider since 2007.
Trend. Medicare records run from 2020 to 2024, 4 years. Volume rose from 12 procedures a year to 40, up 233%.
National context. Among 6,612 knee replacement surgeons tracked nationally, 27 procedures is below the national average of 45. Medicare covers part of all joint replacements, so true volume is likely higher.
Local context. Saint Louis has 57 orthopedic surgeons in the current Medicare data. Comparing volume and procedure mix across them is one way to narrow a shortlist.
Verified Case Volume Trends (2013-Current)
| Year | Hip Replacement | Knee Replacement |
|---|---|---|
| 2013 | 0 | 0 |
| 2014 | 0 | 0 |
| 2015 | 0 | 0 |
| 2016 | 0 | 0 |
| 2017 | 0 | 0 |
| 2018 | 0 | 0 |
| 2019 | 0 | 0 |
| 2020 | 12 | 0 |
| 2021 | 0 | 0 |
| 2022 | 24 | 16 |
| 2023 | 18 | 16 |
| 2024 | 13 | 27 |
Verified Medicare Cases
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. Zehnder Compares
Procedure volume compared to the Missouri state average.
Volume Trend Analysis
Dr. Zehnder's Medicare-recorded procedure volume has trended upward over 4 years, increasing 233% from 12 procedures in 2020 to 40 in the most recent data.
Hospital Affiliations & Quality
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:
An overview of current surgical approaches including robotic-assisted and minimally invasive techniques, implant options, and expected outcomes.
What to Expect on the Day of SurgeryA step-by-step walkthrough of your surgical day, from pre-op preparation through anesthesia, the procedure itself, and the first hours of recovery.
Home Safety: Creating Your Recovery SanctuaryRoom-by-room modifications, equipment recommendations, and fall-prevention strategies to prepare your home for a safe post-surgical recovery.
Medicare Coverage for Joint ReplacementWhat Medicare Part A and Part B cover for joint replacement surgery, including hospital stays, surgeon fees, anesthesia, and physical therapy.
Knee Replacement Recovery Overview
Recovery timelines vary by patient, but here is a general overview of what to expect after knee replacement surgery:
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. Zehnder
How does Dr. Zehnder's procedure volume compare to other Missouri surgeons?
Dr. Zehnder has performed 40 Medicare-verified joint replacement procedures. The Missouri average is 59 procedures per surgeon. Medicare data captures roughly one-third of all joint replacements, so total volume may be higher. Dr. Zehnder ranks #108 out of 204 orthopedic surgeons in Missouri.
What types of joint replacement does Dr. Zehnder perform?
Dr. Zehnder's Medicare data shows procedures in knee replacement (27 cases) and hip replacement (13 cases).
Are there other orthopedic surgeons near Dr. Zehnder in Saint Louis?
Yes. There are 57 orthopedic surgeons in Saint Louis 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 Missouri surgeons.
What does the Medicare data for Dr. Zehnder 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. Zehnder's total volume across all insurers at roughly 140 to 170 procedures against the 40 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.
Has Dr. Zehnder's procedure volume changed over time?
Yes. Dr. Zehnder's Medicare-recorded volume has increased from 12 procedures in 2020 to 40 in the most recent data, a 233% increase over 4 years. This upward trend suggests an expanding joint replacement practice. Peak volume was 40 procedures in 2022.
Does Dr. Zehnder perform more than one type of joint replacement?
Yes. Dr. Zehnder's Medicare data shows procedures in knee replacement (27 cases), hip replacement (13 cases). Surgeons who perform multiple joint replacement types maintain broad technical skills across different anatomical joints.
Which hospitals is Dr. Zehnder affiliated with?
According to CMS facility affiliation data, Dr. Zehnder is affiliated with Missouri Baptist Medical Center, St Lukes Hospital.
How does Dr. Zehnder compare to other orthopedic surgeons in Saint Louis?
Among the 57 orthopedic surgeons in Saint Louis, Dr. Zehnder ranks #32 by total Medicare procedure volume. The highest-volume surgeon in Saint Louis has 279 verified Medicare procedures.
What are the quality ratings for hospitals where Dr. Zehnder practices?
Missouri Baptist Medical Center (4 out of 5 CMS stars, hip/knee complication rate similar to national average); St Lukes Hospital (4 out of 5 CMS stars, hip/knee complication rate similar to national average). These are hospital-level quality metrics from CMS Hospital Compare and do not reflect individual surgeon outcomes.
Other Orthopedic Surgeons in Saint Louis, Missouri
Dr. Zehnder's 40 Medicare procedures are below the Saint Louis average of 147. The table below compares verified procedure volumes for orthopedic surgeons practicing in Saint Louis.
| Surgeon | Procedures | Specialties |
|---|---|---|
| Dr. Ryan Nunley | 279 | Hip, Knee |
| Dr. Christopher Palmer | 160 | Hip, Knee |
| Dr. Michael Hubbard | 144 | Hip, Knee, Shoulder |
| Dr. Coles L'hommedieu | 139 | Hip, Knee |
| Dr. Ilya Bendich | 137 | Hip, Knee |
| Dr. Christopher Mudd | 132 | 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.