When patients are preparing for a hip or knee replacement, one of the most common steps is “medical clearance.” But that phrase can be misleading.
In Episode 51 of The Joint Replacement Podcast, I sat down with Tyler Thurman, DO, an internal medicine physician, hospitalist, and the creator behind @hospitaldoctort, to talk about what medical clearance really means, what physicians are actually looking for before surgery, and which medical issues may truly affect whether a patient is ready for the operating room.
Rather than thinking of clearance as a simple yes-or-no decision, Dr. Thurman prefers the term risk stratification. The goal is not to guarantee that nothing will go wrong. It is to identify acute medical problems, estimate perioperative risk, and determine whether additional testing or treatment is needed before surgery. In his experience, most routine preoperative consultations ultimately result in patients being considered low risk without the need for further testing.
What Can Actually Delay Surgery?
The answer depends heavily on how urgent the operation is.
For an elective procedure, there is often time to investigate a new fever, possible infection, significant cardiac symptoms, or other concerning abnormalities before proceeding. In contrast, hip fracture surgery creates a different situation because unnecessary delays can introduce their own risks. In that setting, the medical and surgical teams may need to balance the benefit of additional testing against the consequences of postponing surgery.
We discussed this tension in detail. A patient may have substantial medical comorbidities, but the question is not simply whether they are “high risk.” The more important question is whether anything can realistically be improved in the available time and whether delaying surgery would actually make the patient safer.
Sodium, Kidney Function, and Other Lab Abnormalities
One of the running jokes between orthopedic surgeons and hospitalists is sodium.
Dr. Thurman explained that a mildly low sodium may not require much attention at all, while progressively lower values can raise more concern. The challenge with more severe hyponatremia is not only determining the cause, but also correcting it safely without changing the sodium too rapidly.
Kidney function is approached in a similar way. Rather than focusing only on whether a creatinine value is “abnormal,” the more relevant issue is whether kidney function is acutely worsening or whether the patient is at their established baseline.
That distinction comes up frequently in perioperative care: abnormal does not always mean unstable.
Diabetes Before Surgery
For elective joint replacement, long-term glucose control is often an important part of surgical optimization.
However, an urgent hospital-based surgery is different. Hemoglobin A1C reflects glucose control over a period of months, so it cannot meaningfully be changed in a day or two. In an urgent setting, the focus shifts more toward recognizing poor baseline control and managing perioperative and postoperative glucose levels appropriately.
This is a good example of why the same laboratory value can have very different implications depending on whether a surgery is elective or urgent.
How Low Is Too Low for Hemoglobin?
Anemia is another common issue in orthopedic patients, particularly after trauma or hip fracture.
Dr. Thurman pointed out that interventions such as iron supplementation or infusion generally do not provide an immediate increase in hemoglobin. For elective patients, there may be time to optimize anemia before surgery. In an acute situation, however, the team may need to make a more immediate decision about transfusion and operative timing.
Again, the key theme is timing. Treatments that make sense weeks before surgery may not help when surgery needs to happen tomorrow.
When Does Cardiology Need to Get Involved?
Preoperative EKGs are common, especially in older patients or those presenting with hip fractures.
The difficult part is deciding which abnormalities actually require additional cardiac evaluation. Dr. Thurman described situations in which obvious ischemic changes or unusual findings may warrant cardiology involvement, while also acknowledging that practice patterns vary significantly between hospitals and anesthesia teams.
This variability is important for patients to understand. There is not always one universal pathway. The decision often involves communication between the surgeon, hospitalist, anesthesiologist, and, when necessary, cardiologist.
What Does “Medically Optimized” Actually Mean?
This was one of the most useful distinctions in the episode.
From Dr. Thurman’s perspective, “medically optimized” does not mean that a patient has perfect health. It means that the patient’s acute medical problems have been addressed, their vital signs and laboratory values are reasonably back to baseline, and their chronic conditions are as stable as they are likely to become in the available timeframe.
A patient can have significant chronic disease and still be medically optimized.
That is very different from expecting every abnormal test result to become normal before surgery.
Do We Still Need Routine Chest X-Rays and Urine Tests?
We also discussed some of the traditional elements of preoperative testing.
Dr. Thurman questioned the usefulness of routine one-view chest X-rays in asymptomatic patients, particularly when the results are nonspecific and do not change management. He similarly discussed the limitations of routine urine testing when there are no symptoms suggesting infection.
The larger point is that more testing does not always equal better care.
The value of any test depends on whether the result is likely to change what happens next.
Orthopedic Surgeons vs Hospitalists
The second half of the episode became a little less serious.
We moved into a rapid-fire discussion about the stereotypes orthopedic surgeons and internists have about each other.
Which is more dangerous: an internist reading a postoperative orthopedic X-ray or an orthopedic surgeon reading an EKG?
Dr. Thurman’s answer: the orthopedic surgeon reading the EKG.
Could a hospitalist reliably distinguish a total knee replacement from a partial knee replacement on an X-ray?
His answer was even more definitive: “Not a chance.”
And when I asked whether orthopedic surgeons are smarter than he expected, his answer may have produced the best line of the episode. He explained that orthopedic surgeons can sound very intelligent when discussing complicated fractures and surgical techniques, but then:
“…they consult me for sodium 132 and, like, all right, out the window.”
Fortunately, he also acknowledged that orthopedic surgery remains a highly competitive specialty.
The Value of Different Perspectives
The humor highlights something important about modern surgical care.
Orthopedic surgeons, hospitalists, anesthesiologists, cardiologists, and other specialists approach patients from different perspectives. That is exactly why multidisciplinary care can be so valuable.
The orthopedic surgeon may be focused on restoring mobility and treating the underlying musculoskeletal problem. The hospitalist may be focused on identifying acute medical instability. The anesthesiologist may be evaluating whether the patient can safely tolerate anesthesia.
None of those perspectives replaces the others.
For patients preparing for joint replacement, the purpose of the preoperative medical evaluation is not to achieve perfect health. It is to identify risks that can realistically be modified, avoid unnecessary testing or delays, and make the perioperative period as safe as possible.
Episode 51 of The Joint Replacement Podcast with Tyler Thurman, DO is available now on YouTube, Spotify, and major podcast platforms.
Topics discussed: medical clearance, perioperative risk stratification, hip replacement, knee replacement, hip fracture, cardiac evaluation, diabetes, anemia, kidney disease, hyponatremia, preoperative testing, hospital medicine, and orthopedic surgery.