Dr. Nicholas Gerken, M.D.
Contact & Location
210-874-3359
San Antonio, TX 78258
Dr. Gerken performs more knee replacement procedures than 39% of orthopedic surgeons in Texas, based on 2024 Medicare claims volume.Derived from the state ranking shown on this page: #295 of 489 ranked knee surgeons in Texas.
About Dr. Gerken
Practice. Dr. Nicholas Gerken is a board-certified orthopedic surgeon practicing in San Antonio, Texas. The latest annual CMS data records 26 knee replacements and 25 hip replacements, 51 procedures in all. That is #295 in Texas for knee replacement. A Medicare provider since 2011.
Trend. Medicare records run from 2019 to 2024, 5 years. Volume rose from 13 procedures a year to 51, up 292%.
National context. Among 6,612 knee replacement surgeons tracked nationally, 26 procedures is below the national average of 45. Medicare covers part of all joint replacements, so true volume is likely higher.
Local context. San Antonio has 41 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 | 13 |
| 2020 | 0 | 0 |
| 2021 | 0 | 20 |
| 2022 | 0 | 32 |
| 2023 | 17 | 32 |
| 2024 | 25 | 26 |
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. Gerken Compares
Procedure volume compared to the Texas state average.
Volume Trend Analysis
Dr. Gerken's Medicare-recorded procedure volume has trended upward over 5 years, increasing 292% from 13 procedures in 2019 to 51 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.
Questions to Ask Your Surgeon Before Joint ReplacementA practical checklist of questions covering experience, technique, hospital choice, and recovery expectations to discuss during your surgical consultation.
Recovery Timeline: Week-by-Week ExpectationsA detailed week-by-week guide covering pain levels, mobility milestones, physical therapy progression, and when to expect a return to daily activities.
Outpatient Joint Replacement: A Medicare GuideHow outpatient joint replacement works under Medicare, including eligibility criteria, cost differences, and what to expect with same-day discharge.
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. Gerken
How does Dr. Gerken's procedure volume compare to other Texas surgeons?
Dr. Gerken has performed 51 Medicare-verified joint replacement procedures. This is in line with the Texas average of 57 procedures per surgeon. Dr. Gerken ranks #230 out of 582 orthopedic surgeons in Texas.
What types of joint replacement does Dr. Gerken perform?
Dr. Gerken's Medicare data shows procedures in knee replacement (26 cases) and hip replacement (25 cases).
Are there other orthopedic surgeons near Dr. Gerken in San Antonio?
Yes. There are 41 orthopedic surgeons in San Antonio 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 Texas surgeons.
What does the Medicare data for Dr. Gerken 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. Gerken's total volume across all insurers at roughly 170 to 210 procedures against the 51 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. Gerken's procedure volume changed over time?
Yes. Dr. Gerken's Medicare-recorded volume has increased from 13 procedures in 2019 to 51 in the most recent data, a 292% increase over 5 years. This upward trend suggests an expanding joint replacement practice. Peak volume was 51 procedures in 2024.
Does Dr. Gerken perform more than one type of joint replacement?
Yes. Dr. Gerken's Medicare data shows procedures in knee replacement (26 cases), hip replacement (25 cases). Surgeons who perform multiple joint replacement types maintain broad technical skills across different anatomical joints.
Which hospitals is Dr. Gerken affiliated with?
According to CMS facility affiliation data, Dr. Gerken is affiliated with Methodist Hospital Stone Oak, Medina Regional Hospital, Baptist Medical Center, Methodist Hospital.
How does Dr. Gerken compare to other orthopedic surgeons in San Antonio?
Among the 41 orthopedic surgeons in San Antonio, Dr. Gerken ranks #19 by total Medicare procedure volume. The highest-volume surgeon in San Antonio has 383 verified Medicare procedures.
What are the quality ratings for hospitals where Dr. Gerken practices?
Methodist Hospital Stone Oak (3 out of 5 CMS stars, hip/knee complication rate similar to national average); Baptist Medical Center (3 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 San Antonio, Texas
Dr. Gerken's 51 Medicare procedures are below the San Antonio average of 186. The table below compares verified procedure volumes for orthopedic surgeons practicing in San Antonio.
| Surgeon | Procedures | Specialties |
|---|---|---|
| Dr. Christopher Phelps | 383 | Hip, Knee, Shoulder |
| Dr. Bryan Kaiser | 235 | Hip, Knee |
| Dr. Richard Ursone | 191 | Hip, Knee, Shoulder |
| Dr. Casey Taber | 172 | Hip, Knee |
| Dr. Robert Girling | 155 | Hip, Knee |
| Dr. Matthew Morrey | 116 | 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.