Identifying Origins and Insertions
Once you have launched a View from the Anatomy or Index sections, you can identify muscle origins and insertions within that View by using muscle pins or bone landmarks.
Red pins mark the location of a muscle’s origin, and blue pins mark its insertion. Clicking on the head of a pin displays the muscle in the model (if it is not showing already) and labels it with its name. Each pin allows you to navigate between the origins and insertions of that muscle by clicking on the icon(s) to the right of the label.
If you click on a red pin to view the origin of a muscle, an icon showing a curved arrow and a blue pin will appear next to the text label. Clicking once on this icon causes the model to automatically reorient on the screen to show that muscle’s insertion. The view centers and highlights the blue insertion pin and displays the insertion label. The icon next to the insertion label shows an arrow and a red pin. Clicking this icon returns you to the origin of the muscle.
Many muscles have multiple origins and/or insertions. In these cases, clicking one of the pins highlights all other pins of the same type (origin or insertion) for that muscle. Clicking a blue insertion pin, for example, highlights all the insertion pins for that muscle by turning them a brighter shade of blue. A multiple insertion icon showing a straight arrow and multiple pins appears next to the label. Repeatedly clicking on this icon sequentially centers and labels all the insertions of that muscle. A second icon showing a curved arrow and a red pin also appears next to each insertion label, bringing you to the origin(s) of that muscle.
Pins are turned on automatically in Anatomy Views. You can customize which pins are shown by using the buttons at the left side of the screen. To turn on the pins in a View, select the structure(s) for which you would like to view pins (either a muscle or a bone) and click “Show Pins”. To hide pins for one or more specific structures, select the structure(s) for which you wish to turn off the pins and click “Hide Pins”. To clear all pins from a View, make sure there are no structures highlighted and then click “Clear All Pins”.
Red and blue markings on bones show the surface areas where muscles attach. These landmarks are colored red for muscle origins and blue for muscle insertions. Landmarks can be switched on or off for all skeletal structures appearing in a View by clicking the “Landmarks On” or “Landmarks Off” button at the left of the screen.
You can identify which muscles attach to bone landmarks by selecting the bone and clicking “Show Pins”. Each red landmark matches up with a red pin (denoting an origin), and each blue landmark matches up with a blue pin (denoting an insertion). Clicking once on the head of the pin shows the muscle and labels it with its name.
For example, the frontal bone of the skull has six red landmarks displayed. Showing the pins and clicking the pin heads reveals that the temporalis muscles, the corrugator supercilii muscles, and the orbicularis oculi muscles all originate from the frontal bone of the skull.