It’s mouthful, yes, but you use this muscle everyday when you raise your eyebrows. You might do this when you are surprised or frightened. Boo!

The front part of this muscle starts under the skin where your eyebrows are located. It then travels back to the top of the head, blending into a layer of thick connective tissue which then blends into the back (occipital) portion of the muscle. This portion rests at the occipital ridge, the bony part of the skull where the neck starts.

The occipitofrontalis is one of thirty mimetic muscles – muscles that express emotion. Prolonged stress, concentration, or fear can exhaust this muscle.

Tension can set up trigger points which can cause headaches and eye pain. It’s easy to access this muscle to massage it; you probably do it often without even realizing.

In this depiction by Primal Pictures you can see the frontal and occipital bellies, but not the connecting tissue. The muscle belly at the side of the skull is the temporalis muscle.

In this rendering by Primal Pictures, the gemellus may be difficult to locate. The muscle at the top (it’s cut off by the border) is the quadratus lumborum. Below that angling diagonally toward the hip bone is the piriformis. Below the piriformis, laying almost horizontally, is the gemellus.

The gemellus, along with the piriformis, are part of the “deep six”, a group of hip muscles responsible for external rotation. If you can kick a soccer ball with the inside part of your foot it’s because you can externally rotate your hip. Sitting cross legged also requires the strength to externally rotate. (It also requires flexibility in the adductors, another topic.)

Trigger points that develop in the gemellus can be expected to behave like trigger points in the piriformis. Hip pain and a pain in the butt would be common. Lost range of motion (hip rotation) could follow if treatment was incomplete. In order for a massage therapist to access the gemellus, she’ll have to work through the gluteus maximus, a large muscle that lays superfically on top of the deep six.

The supinator (the muscle shown at the top of this picture) is a small, deep muscle in your forearm; it is located on the outer (lateral) side of the forearm near the elbow. In the forearm, supination is the action of turning the forearm into a position where your palm is facing upward or forward. The supinator muscle is well named because all it does is supinate. It’s easy to remember the action of the muscle because it puts your hand into a position to hold soup. (Not that I recommend holding soup in your hand!)

When performing bicep curls with dumbells you would call the supinator into play as you curl the weights toward your chest. See the position of the palms? They’re supinated. Using a (manual) screwdriver requires strength and stamina in the supinator. Turning some doorknobs require the use of the supinator.

Trigger points in the supinator can be dificult to distinguish from trigger points in other forearm muscles. Pain is felt near the lateral part of the elbow and at the base of the thumb. The thumb may also present with a vague numbness.

The rotatores are tiny, thick muscles that help “stitch” the vertebrae together. These muscles of the back compose the deepest layer and are responsible for the ability to rotate or twist your spine.

Individual rotatore muscles attach the transverse process of one vertebra to the spinous process of another; this gives it a diagonal placement which causes the rotation when the muscle is put to use. The whole group of rotatores are placed from the lumbar to the cervical vetebrae. Along with two other groups of small spinal muscles, they make up the transversospinalis group.

People with very tight or contracted rotatores may appear to have a stiff back with very limited ability to make minute, subtle spinal movements. Trigger points in the rotatores refer pain close to the source; generally a client will describe pain right next to the spine. Often releasing tension in the deep spinal muscles can make chiropractic adjustment easier. Occasionally, a client will have a “spontaneous adjustment” after trigger points are released.

The gastrocnemius is one of several calf muscles. Because the gastrocnemius cross two joints it is responsible for two distinct movements.

With its two short tendons attaching to the bottom end of the femur (thigh bone), the gastroc allows you to bend (flex) your knee. The long, inferior tendon was made rather famous by stories about a Greek warrior name Achilles. The Achilles tendon (more properly called the calcaneal tendon) crosses the ankle to attach to the heal bone (the calcaneus), allowing you to point your toe, also known as plantar flexion.

Many activities this holiday season may cause overuse in the gastrocs. Walking up stairs and escalators at the mall, inching along in traffic unable to use cruise control, and standing in line at the post office can create conditions that trigger points find attractive. Trigger points in the gastroc usually cause localized pain and pain in the arch of the foot.

Flying long distances can cause calf trouble for people at risk for deep vien throbmosis (DVT). Cramping in the calves can be caused by trigger points, poor circulation, or inadequate nutrition, especially calcium and magnesium.

Although it sounds like an obscure general from the Roman Empire, the splenius capitis is actually a neck and head muscle. You have a splenius capitis (SC) on each side of the neck attaching along the vertebrae of the upper back at one end and on the other end attaching to the skull at the mastoid process (just behind your ear).

Contracting the SC on one side will rotate and/or laterally flex (bring ear to shoulder) your neck on that same side. Looking up (extension) requires contraction of both SC simultaneously.

As a neck muscle the splenius capitis is susceptible to injuries such as whiplash. Trauma involving the neck or head can allow trigger points to develop in this muscle. Over or misuse of the muscle (especially related to posture) can also set the stage for trigger points.

Trigger points in the splenius capitis generally refer pain to the top of the head. Headaches of this nature can be relieved if trigger points are causing them and can be deactivated.

The adductor pollicis (AP) is a small, but powerful thumb muscle. The bulk of the muscle can be found by squeezing the tissue in the webbing between the thumb and the index finger. This muscle helps bring the thumb (pollicis) toward the fingers by an action called adduction.

Adducting the thumb allows us to enjoy our opposable thumb status. Because of the AP you can use utensils to eat and tools to build. You use this muscle to open jars and doors, throw a Frisbee, text your friends, and hold a brush to paint the house. Overusing, underusing, or injuring the AP can set up trigger points in the muscle.

Trigger points in the AP can refer pain to the base of the thumb, complicating or intensifying pain associated with arthritis. Deactivating the trigger points can reduce the “pain load” carried in the thumb.

The psoas (SO-az) muscle is a very important hip flexor. As such it is attached to the upper, inside femur (lesser trochanter) and to the front (anterior) of the lumbar vertebrae. On top of the psoas muscles lay the intestines and on top of that are positioned the abdominal muscles.

All walking, running, crawling, and kicking activities require you to activate your psoas muscles. In order to sit comfortably your psoas has to be able to relax; sitting for prolonged periods, however can be a perpetuating factor in pain and dysfunction. A psoas that can’t relax can also prevent you from standing up straight, giving you a stooped appearance.

When the psoas has become stuck in contraction or has developed trigger points, the problem generally manifests as low back pain. Sometimes problems also show up as groin pain. A skilled therapist will investigate the psoas of a client who presents with low back pain.

image credited to Real BodyWork