The trapezius muscle is a large flat superficial triangular muscle covering the back of the neck and shoulder.
It is sometimes described in terms of three parts or regions of the trapezius muscle. They are the:
- Superior (upper) fibres, also called the 'descending fibres'
- Middle fibres, and the
- Inferior (lower) fibres, also called the 'ascending fibres'.
Origin, Insertion and Actions of the (whole) Trapezius muscle:
|Points of Origin:||
|Points of Insertion:|
It is not surprising that such an extensive muscle has so many actions. Different textbooks and websites list and describe the actions of the trapezius muscle in slightly different ways. There is no single consistent number of actions of trapezius muscle. The most detailed descriptions indicate the actions of specific parts (groups of fibres) of this muscle, together with examples of movements caused or supported by the trapezius muscle. An example of a short list of its actions is:
- Stabilises the scapula
- Elevation, rotation, and adduction of the scapula
- Some extension and rotation of the neck.
Overall, many of the actions of the trapezius muscle involve moving the scapula bone and/or the clavicle bone or head/neck.
The word 'trapezius' is derived from the Greek word trapezoides, which means 'table shaped'.
More about Muscles:
The following are some popular pages in the section about the human muscular system:
- The structure of muscle tissue
- The structure of muscle cells
- Labelled diagrams of the muscles in different parts of the body including anterior muscles, posterior muscles and facial muscles
- Types of muscle contractions
- Movements at joints
There are also more pages about the words used to describe muscles (terminology), the anatomy and physiology of muscles, muscular disorders and associated topics. See also books about sports medicine.
- Anterior Muscles
- Posterior Muscles
- Facial Muscles
- Muscle Terminology (Definitions)
- 1. Structure of Muscle
- 2. Structure of Muscle Cells
- 3. Muscle Filaments
- 4. Sliding Filament Theory
- 5. Neuromuscular Junction
- 6. Actions at Neuromuscular Junction
- Types of Muscle Contractions
- Muscular Disorders
- Effects of exercise on muscles