Modelling the muscles of the scapula morphometric and coordinate data and functional implications

Area of Science:

• Biomechanics
• Anatomy
• Orthopedics

Background:

• Shoulder mechanism modeling relies on precise morphometric data and muscle attachment points.
• Existing anatomical data may have discrepancies, impacting biomechanical model accuracy.

Purpose of the Study:

• To present normalized coordinate data from dissected cadaver radiography for shoulder muscles.
• To provide normalized physiological cross-section area (PCSA) measurements for shoulder muscles.
• To compare these findings with existing biomechanical literature.

Main Methods:

• Radiographic analysis of dissected cadavers to obtain muscle attachment coordinates.
• Normalization of coordinate data relative to humerus, scapula, clavicle, and trunk dimensions.
• Normalization of PCSA measurements relative to the deltoid muscle's PCSA.

Main Results:

• Normalized coordinate data and PCSA measurements for key shoulder muscles were established.
• PCSA measurements largely align with previous studies by Veeger et al. and Karlsson and Peterson.
• Morphometric descriptions generally agree with accepted texts, with specific discrepancies noted for the trapezius muscle.

Conclusions:

• The presented normalized data offer a reliable resource for shoulder mechanism modeling.
• The findings contribute to a more accurate understanding of shoulder muscle anatomy and function.
• Discrepancies in trapezius morphometry warrant further investigation for improved biomechanical models.