Combined Motions of the Shoulder Joint Complex for Model-Based Simulation: Modeling of the Shoulder Rhythm (ShRm) - 3D Multiscale Physiological Human - page 203

Table 9.1 ALs used in this research for ShRm analysis. Most ALs in the list are readily palpable
through the subject's skin
Segments Anatomical landmarks
Acronyms Names
Spine MTV3, MTV8 Thoracic spinous processes
Sternum MSJN Jugular notch
MSXS XiphiSternal joint
Clavicle LCAJ, RCAJ Acromioclavicular joint
LCSJ, RCSJ Sternoclavicular joint
LCAS, RCAS Anterior sternoclavicular joint
Scapula LSIA, RSIA Inferior angle
LSRS, RSRS Root of spine
LSAJ, RSAJ Acromioclavicular joint
Humerus LHCH, RHCH Humeral head center
LHME, RHME Medial epicondyle
LHLE, RHLE Lateral epicondyle
Ulna LUSP, RUSP Styloid process
Not palpable ALs (such as joint centres like the humeral head centre in the list) are approximated
using the coordinates of palpable ALs within regression procedures [ 74 ]. These ALs are visible in
Fig. 9.2
that aims to estimate clavicle and scapula displacements from humerus instantaneous
postures, must first deal with the primary nature of the observed shoulder girdle dis-
placements, i.e. simultaneous clavicle elevation within the sternoclavicular joint with
scapula gliding on the thorax via the scapulothoracic joint, combined or not with a
humerus displacement within the scapulohumeral joint. This is the purpose of this
research.
The next section describes the anatomical landmarks required for shoulder motion
characterization first. Then, the entire data collection protocol, including in-vivo
validation activities, is given. Finally, the newly-developed method to estimate the
various components of the shoulder rhythm is explained.
9.2.1 Anatomical Landmarks for the Upper Limb
The palpation protocol is fully described in Van Sint Jan [ 73 ]. The list of ALs used in
this work for the upper limbs and thorax is given in Table 9.1 . These ALs are used for
several tasks related to modeling anthropometric measurements, anatomical features
approximation using regression procedures, data registration and data fusion, joint
reference frame construction and motion representation. Accurate and reproducible
AL palpation and AL spatial location is therefore important to increase result vali-
dation, and strict and standardized definitions facilitate result comparison [ 73 ]. This
must be kept in mind when using modeling algorithms integrating 3D locations of