Dr. Aaron Johnson, M.D.
Contact & Location
410-448-6400
Baltimore, MD 21201
Richmond, VA 23298
Dr. Johnson performs more hip replacement procedures than 56% of orthopedic surgeons in Maryland, based on 2024 Medicare claims volume.Derived from the state ranking shown on this page: #39 of 89 ranked hip surgeons in Maryland.
About Dr. Johnson
Practice. Dr. Aaron Johnson is a board-certified orthopedic surgeon practicing in Baltimore, Maryland. The latest annual CMS data records 34 hip replacements and 20 knee replacements, 54 procedures in all. That is #39 in Maryland for hip replacement. A Medicare provider since 2012.
Trend. Medicare records run from 2020 to 2024, 5 years. Volume rose from 12 procedures a year to 54, up 350%.
National context. Among 4,542 hip replacement surgeons tracked nationally, 34 procedures is near the national average of 36.
Local context. Baltimore 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 | 0 |
| 2020 | 12 | 0 |
| 2021 | 34 | 12 |
| 2022 | 43 | 20 |
| 2023 | 45 | 34 |
| 2024 | 34 | 20 |
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 25% to 33% for hip replacement, 23% to 28% for knee 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. Johnson Compares
Procedure volume compared to the Maryland state average.
Volume Trend Analysis
Dr. Johnson's Medicare-recorded procedure volume has trended upward over 5 years, increasing 350% from 12 procedures in 2020 to 54 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 Hip Replacement
If you are considering hip replacement surgery, these evidence-based guides can help you prepare and recover:
Understanding the progression from conservative treatments to surgical intervention, and how to determine when hip replacement becomes the right choice.
Prehabilitation: Preparing Your Body for SurgeryEvidence-based exercises and lifestyle adjustments that can improve surgical outcomes and speed recovery when started weeks before your procedure.
Rehabilitation Roadmap: Your Complete Recovery GuideA structured physical therapy progression from the first post-op exercises through full strength and mobility restoration over 3 to 6 months.
Medicare Bundled Payment Programs for Joint ReplacementHow bundled payment models affect your joint replacement costs and care coordination, and what it means for hospital and surgeon selection.
Hip Replacement Recovery Overview
Recovery timelines vary by patient, but here is a general overview of what to expect after hip replacement surgery:
Individual recovery varies based on overall health, age, and adherence to physical therapy. View full hip replacement recovery guide and product recommendations
Frequently Asked Questions About Dr. Johnson
How does Dr. Johnson's procedure volume compare to other Maryland surgeons?
Dr. Johnson has performed 54 Medicare-verified joint replacement procedures. The Maryland average is 71 procedures per surgeon. Medicare data captures roughly one-third of all joint replacements, so total volume may be higher. Dr. Johnson ranks #80 out of 166 orthopedic surgeons in Maryland.
What types of joint replacement does Dr. Johnson perform?
Dr. Johnson's Medicare data shows procedures in hip replacement (34 cases) and knee replacement (20 cases).
Are there other orthopedic surgeons near Dr. Johnson in Baltimore?
Yes. There are 41 orthopedic surgeons in Baltimore 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 Maryland surgeons.
What does the Medicare data for Dr. Johnson 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 25% to 33% for hip replacement, 23% to 28% for knee replacement, which puts Dr. Johnson's total volume across all insurers at roughly 170 to 220 procedures against the 54 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. Johnson's procedure volume changed over time?
Yes. Dr. Johnson's Medicare-recorded volume has increased from 12 procedures in 2020 to 54 in the most recent data, a 350% increase over 5 years. This upward trend suggests an expanding joint replacement practice. Peak volume was 79 procedures in 2023.
Does Dr. Johnson perform more than one type of joint replacement?
Yes. Dr. Johnson's Medicare data shows procedures in hip replacement (34 cases), knee replacement (20 cases). Surgeons who perform multiple joint replacement types maintain broad technical skills across different anatomical joints.
Which hospitals is Dr. Johnson affiliated with?
According to CMS facility affiliation data, Dr. Johnson is affiliated with University Of Maryland Medical Center, Umd Baltimore Washington Medical Center, University Of Md Capital Region Medical Center, Umd Rehabilitation & Orthopaedic Institute.
How does Dr. Johnson compare to other orthopedic surgeons in Baltimore?
Among the 41 orthopedic surgeons in Baltimore, Dr. Johnson ranks #23 by total Medicare procedure volume. The highest-volume surgeon in Baltimore has 331 verified Medicare procedures.
What are the quality ratings for hospitals where Dr. Johnson practices?
University Of Maryland Medical Center (2 out of 5 CMS stars, insufficient case volume for complication rate comparison); Umd Baltimore Washington Medical Center (4 out of 5 CMS stars, hip/knee complication rate similar to national average); University Of Md Capital Region 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 Baltimore, Maryland
Dr. Johnson's 54 Medicare procedures are below the Baltimore average of 169. The table below compares verified procedure volumes for orthopedic surgeons practicing in Baltimore.
| Surgeon | Procedures | Specialties |
|---|---|---|
| Dr. Joseph Ciotola | 331 | Hip, Knee, Shoulder |
| Dr. Frank Ebert | 190 | Hip, Knee |
| Dr. Marc Hungerford | 180 | Hip, Knee |
| Dr. Robert McKinstry | 160 | Hip, Knee |
| Dr. Mark Hasenauer | 146 | Hip, Knee |
| Dr. Harpal Khanuja | 119 | 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.