10/14/2026
The problem with representing what the best golfers do without a systematic biomechanical model is that it becomes difficult to draw accurate conclusions about their movements. This problem is compounded by the limitations of 3D sensor systems, including GEARS, in accurately representing individual anatomical joint motions.
Three-dimensional motion analysis is subject to several important limitations: kinematic cross-talk, soft-tissue artifact, and the difficulty of establishing accurate anatomical reference systems for individual joints. Kinematic cross-talk can cause rotations in one plane to be misrepresented as rotations in another. Soft-tissue artifact occurs when sensors or markers move relative to the underlying bones. Inaccurate or inappropriate anatomical reference frames can further distort the interpretation of calculated joint angles.
These limitations are particularly important when analyzing the shoulder. Humeral motion relative to the trunk is not the same as humeral motion relative to the scapula. Shoulder external/internal rotation and horizontal abduction/adduction are distinct anatomical motions that must be identified using appropriate reference frames and a valid biomechanical model. A three-dimensional representation does not, by itself, establish that the individual joint motions have been accurately measured or labeled.
Here, AMG incorrectly represents the trail shoulder’s external rotation and horizontal adduction. In its demonstration, the cubital fossa faces toward the target, whereas the elite golfers demonstrate a more externally rotated humeral position, with the humerus horizontally adducted toward the body’s midline.
The following catalog of the world’s leading male golfers and the No. 1 female golfer illustrates these differences and provides a basis for comparing AMG’s representation with the movements demonstrated by elite players.
The fundamental question is whether AMG’s anatomical labels and biomechanical interpretations accurately represent the actual motions of the trail shoulder—and, consequently, what the best golfers really do.
