Training and experience are matters of record. Here is what the record can and cannot tell you.
Two facts about a surgeon can be documented: how they trained, and roughly how many knee replacements they do a year. Both have been studied at the population level. This article explains what each fact means, what the studies found, and what a candid conversation with a surgeon sounds like.
Fellowship training in adult reconstruction is a documented year of specialisation
An orthopaedic surgeon completes a five-year residency. A fellowship-trained adult reconstruction surgeon has then spent at least one further year training in joint replacement, including atypical deformity, dysplasia, and replacement after trauma 1. The American Association of Hip and Knee Surgeons requires its fellow-level members to be board certified and to do at least 50 joint replacements a year 1.
A fellowship is a fact about training, not a guarantee about any one operation.
The volume studies found a relationship, and defined volume differently each time
A systematic review of 11 studies on surgeon volume and knee replacement found that low volume was defined anywhere from fewer than 3 to fewer than 52 operations a year, and high volume from more than 5 to more than 70 2. Across those studies, low surgeon volume was associated with more infection, longer operations, longer hospital stays, more transfusions, and worse patient-reported outcomes 2. Mortality, blood clots, and implant survival were not associated with surgeon volume, and the authors wrote that the results must be interpreted with caution 2.
A later analysis let the data set its own thresholds. For knee replacement it identified four surgeon bands, 0 to 12, 13 to 59, 60 to 145, and 146 or more a year, with complication rates falling across each band 3. Revision rates fell too, but not between the top two bands 3. For hospitals the bands were 0 to 89, 90 to 235, 236 to 644, and 645 or more a year, with complications no longer falling above 236 3.
A meta-analysis of 68 studies found that each additional 50 knee replacements a hospital does per year was associated with about 9 percent lower odds of death within three months, and no clear association for deep infection or late revision 4.
A number is a record, not a verdict
The thresholds disagree with each other: low volume was set anywhere from fewer than 3 to fewer than 52 a year in one review, and the bands began at 13, 60 and 146 in another, depending on the study and the outcome 23. That is what a population finding looks like when the question is asked several ways.
What a candid conversation about approach and implant sounds like
A candid surgeon will name the approach they plan and say why it suits your anatomy, rather than presenting it as the only one. They will name the implant and say how long that design has been in use and what registry follow-up it has. They will say what they do when something goes wrong, and who else will be in the room.
The clearest sign is specificity. A plan that mentions your X-ray, your deformity, your other health conditions, and your goals has been made for you. A plan that would read the same for anyone has not yet been.
What to ask your surgeon
- Did you complete a fellowship in adult reconstruction, and where?
- Roughly how many knee replacements do you do in a year, and how many at this hospital?
- Which approach do you plan for me, and why this one for my anatomy?
- Which implant will you use, how long has it been in use, and what does the registry data show for it?
- What complications have you seen in patients like me, and how did you manage them?
Training and volume are records you are entitled to ask about. What they mean for your operation is decided with your surgeon, from your exam, imaging, and history.
This is general education drawn from published sources. It is not a diagnosis or a recommendation for you; your surgeon decides from your exam, imaging, and history, and their instructions come first.
Sources
What this article stands on
- AAHKS hipkneeinfo.org — What it means to be a member of AAHKS ↗
- Lau et al., BMC Musculoskelet Disord 2012 — The role of surgeon volume on patient outcome in total knee arthroplasty: a systematic review ↗
- Wilson et al., J Bone Joint Surg Am 2016 — Meaningful thresholds for the volume-outcome relationship in total knee arthroplasty ↗
- Kugler et al., Knee Surg Sports Traumatol Arthrosc 2022 — Hospital volume-outcome relationship in total knee arthroplasty: systematic review and dose-response meta-analysis ↗
Last checked against these sources 2026-09-03.
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