McClure (2001) used bone pins drilled into the scapular spine of 8 healthy volunteers to directly measure 3D scapular motion during dynamic arm elevation. The study asked: what does normal scapular kinematics actually look like when tracked without the distortion of surface markers? The answer revealed that three planes of rotation operate simultaneously, with two of them — posterior tilting and external rotation — largely missed by prior 2D methods.
McClure (2001) used bone pins drilled into the scapular spine of 8 healthy volunteers to directly measure 3D scapular motion during dynamic arm elevation. The study asked: what does normal scapular kinematics actually look like when tracked without the distortion of surface markers? The answer revealed that three planes of rotation operate simultaneously, with two of them — posterior tilting and external rotation — largely missed by prior 2D methods.