Video commentary excerpt
... Start of condylar movement on opening:
• The bi-condylar horizontal hinge axis and the moving vertical and sagittal axes are purple, and performing a pure rotation
• In this rotation space the shift is minimal but the effect on the dysfunction observed clinically is very important, in fact, in this example the discs cap their condyles but the hypercondylia can cause compression of the left retro condylar area or a predisposition to arthritis or osteoarthritis of the right side.
• Simultaneously the axe hinges of the vertical and sagittal displacement separate to form an opening angle relative to their original counterparts
From the IOM - through the end of the pure condylar rotation until the POM (light blue line)
• From the end of the condylar rotation the displacement is performed by a rotary-linear combination
• Despite the hypercondylia the triaxiogrammes appear harmonious, in effect in the absence of disc dislocation, the condyles draw curves with no offset, but can be shorter on one side compared to the other.
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