It goes without saying that preoperative planning coupled with surgical experience, technique, and intraoperative adaptability are key ingredients to the successful outcome of shoulder arthroplasty. Preoperative planning allows the surgical team to grapple - before scrubbing in - with the anticipated pathoanatomy and the decisions that will have to made at surgery .
Traditionally, preoprerative planning was based on the physical examination and standard imaging of the shoulder, including standardized plain films with the addition of CT and MRI as necessary.
Recently introduced innovations in preoperative planning and plan implementation include three-dimensional simulation software, image guided navigation, patient specific instrumentation, virtual reality, and mixed reality.
While the effectiveness of these innovations in improving clinical outcomes for the patient remains to be rigorously demonstrated, the advocates of these innovations point to the improved accuracy and precision of component placement that can be achieved:
Reliability and accuracy of 3D preoperative planning software for glenoid implants in total shoulder arthroplastyPrecision refers to the degree of reproducibility or repeatability of the placement - doing it the same way each time. Accuracy, on the other hand, refers to the degree of closeness between the desired and the actual placement - how close do we need to be to what target?
If we think of the field goal in American football, we note that the ball doesn't need to be accurately positioned in the center of the uprights nor does it need to be reproducibly positioned, it just needs to pass between the uprights to get the team three points.
With respect to accuracy, the outcome (number of points generated) for each of the two sets of six kicks shown below would be the same.
We need to learn how much accuracy is needed to get our patients the outcome they want. This is difficult, because we have yet to learn where the goal posts are, for example with respect to version correction and reverse total shoulder component position.
As shown below, precision in and of itself cannot be the goal.
As we design studies to determine the clinical value of planning innovations, we need define the degree of accuracy and precision needed to achieve the desired outcome for the patient. Do we know where goalposts are - where is the target - and how wide apart are the uprights? As pointed out in Influence of Backside Seating Parameters and Augmented Baseplate Components in Virtual Planning for Reverse Shoulder Arthroplasty, surgeons vary widely in their targeted position for total shoulder arthroplasty components.
You can support cutting edge shoulder research and education that are leading to better care for patients with shoulder problems, click on this link.
Follow on twitter: https://twitter.com/RickMatsen or https://twitter.com/shoulderarth
Follow on facebook: click on this link
Follow on facebook: https://www.facebook.com/frederick.matsen
Follow on LinkedIn: https://www.linkedin.com/in/rick-matsen-88b1a8133/
Here are some videos that are of shoulder interest
Shoulder arthritis - what you need to know (see this link).
How to x-ray the shoulder (see this link).
The ream and run procedure (see this link).
The total shoulder arthroplasty (see this link).
The cuff tear arthropathy arthroplasty (see this link).
The reverse total shoulder arthroplasty (see this link).
The smooth and move procedure for irreparable rotator cuff tears (see this link).
Shoulder rehabilitation exercises (see this link).
