Comparative analysis of 2 glenoid version measurement methods in variable axial slices on 3-dimensionally reconstructed computed tomography scans.
These authors opine that "Variability of the vault according to slice height and angulation has not yet been studied and is crucial for proper surgical implant positioning."
They analyzed the variation of the glenoid vault (VM) compared with the Friedman angle (FA) according to different CT slice heights and angulations.
These authors opine that "Variability of the vault according to slice height and angulation has not yet been studied and is crucial for proper surgical implant positioning."
They analyzed the variation of the glenoid vault (VM) compared with the Friedman angle (FA) according to different CT slice heights and angulations.
Their hypothesis was that the Friedman angle would show less variability.
Sixty shoulder CT scans were retrieved from a hospital imaging database and were reconstructed in the plane of the scapula. Seven axial slices of different heights and coronal angulations were selected, and measurements were carried out by 3 observers.
Mid-glenoid mean version was −8.0° ± 4.9°; range, −19.6° to +7.0°) and −2.1° ± 4.7°; range, −13.0° to +10.3°) using the vault method and Friedman angle, respectively. Increasing slice height or angulation significantly increased anteversion for the vault method (P < .001).
Above is an example of 3-dimensionally reconstructed axial computed tomography slices at various heights and angulations and their influence on the Friedman angle (F, dashed lines) and vault method (V, solid lines), including mid glenoid (0°), 13 mm from the inferior glenoid border (13mm inf), and 10 mm from the superior glenoid border (10mm sup). Positive and negative angulated slices represent upward and downward glenoid tilt, respectively. This example shows some of the CT imaging variables that can change the determination of glenoid version.
They concluded that "glenoid version at the mid and lower glenoid is similar using either method. The vault method shows less reliability and more variability according to slice height or angulation. Yet, as it significantly differs from the Friedman angle, it should still be used in situations where maximum bone purchase is sought with glenoid implants. For any other situation, the Friedman angle remains the method of choice."
They concluded that "glenoid version at the mid and lower glenoid is similar using either method. The vault method shows less reliability and more variability according to slice height or angulation. Yet, as it significantly differs from the Friedman angle, it should still be used in situations where maximum bone purchase is sought with glenoid implants. For any other situation, the Friedman angle remains the method of choice."
Comment: The real question is "how complicated do we need to make the measurement of glenoid version; has it been shown that spending time and money on 3D reformatting or measurements at different glenoid levels leads to better patient outcomes? " See these related posts (link and link)?
Perhaps an even better question is whether we need CT scans at all in routine cases of shoulder arthritis to (a) plan the surgery and (b) evaluate the radiographic outcome. As shown below, pretty much all we need to know in most cases can be gleaned from standardized axillary views with less cost and less radiation to the patient.
Perhaps an even better question is whether we need CT scans at all in routine cases of shoulder arthritis to (a) plan the surgery and (b) evaluate the radiographic outcome. As shown below, pretty much all we need to know in most cases can be gleaned from standardized axillary views with less cost and less radiation to the patient.
Be sure to visit "Ream and Run - the state of the art" regarding this radically conservative approach to shoulder arthritis at this link and this link
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How you can support progress in shoulder surgery
You may be interested in some of our most visited web pages arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'
How you can support progress in shoulder surgery
You may be interested in some of our most visited web pages arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'
