Nail courses – Muscles of the leg
On the plantar side there are the big toe, the thenar muscle of the little toe and the mesothenar muscles (lumbrical and interosseous muscles) on the dorsal side there are interosseous as well as tiny extensor muscles (which cannot be found in the hand).
The long muscles of the leg are extensors on the anterior side, flexors on the posterior side and fibular muscles on the lateral side. Tendons of these are highly important for maintaining the arch of the foot.
The accessory parts of muscles are those which reduce friction:
- muscular tubes,
- tendon sheaths (tube-like sheaths that ensure easy slipping, and usually enclose tendons running under strong fastening ligaments, in many cases, on the constant deflection points of limbs e.g. wrist, fingers or commonly on e.g. ankle).
Based on their direction of movement skeletal muscles can be:
Division of skeletal muscles based on the parts of the body:
- muscles of the head (e.g. mimicry, manducatory),
- muscles of the neck (e.g. muscle that allows flexing and rotating the head)
- muscles of the back (e.g trapezius muscle, intercostal muscle, erector muscle of spine),
- muscles of the abdomen (outer and inner oblique),
- muscles of the upper limb (e.g. shoulder muscles, upper arm, forearm),
- muscles of the hand (thenar muscles of thumb and little finger and of the middle of palm),
- lower limb muscles (e.g.hip muscles, thigh muscles, leg),
- foot muscles ( dorsal and plantar muscles).
Classification on the basis of their function related to each other:
- synergistic muscles, or in other words, those which function together,
- antagonistic muscles (when one contracts, other relaxes).
Functions of the muscular system:
- Active muscular system organs of motion.
- Fix the joints.
- Create heat.
- Participate in stimulating venous circulation (suction effect on veins).
- Having protecting role (e.g. abdomen muscle).
- Contribute to the aesthetic appearance of the body as well.