The human musculoskeletal system consists of muscles and joints. There are over 640 muscles in the human body. The muscle tissues tighten and release to make movements possible. Muscles account for approximately one half of a person’s body weight.
The diagram above shows 30 of the major muscles in the human body. There are three types of muscles. The three types of muscles are striated, smooth, and cardiac.
Striated muscles are also called skeletal or voluntary muscles. These are the muscles that move the bones as well as control the face and eyes. Striated muscles can be consciously controlled.
Smooth muscles are also known as visceral, involuntary, or unstriated muscles. The body has no control over these muscles, which move the internal organs. Blood vessels and secretory ducts also contain smooth muscles.
Cardiac muscles are a combination of the striated and smooth muscles. These muscles are striated in appearance but movement cannot be controlled. Branching fibers from the cardiac muscles form most of the wall of the heart and control the heartbeat.
In preparing this lesson we were faced with the overwhelming reality that there are an estimated 642 muscles in the human body. We decided to create individual lessons for each of the major muscle groups. Before proceeding to the major muscle groups, we’ll list the important root words and suffixes related to muscles.
| Root Words For the Muscular System | |
| Duct/o | To draw |
| Fasci/o | Band of tissue surround muscle |
| Flex/o | Bend |
| Leiomy/o | Smooth visceral muscle |
| My/o | Muscle |
| Myocari/o | Heart muscle |
| Myos/o | Muscle |
| Pronati/o | Backward or facing down |
| Rhabdomy/o | Skeletal or striated muscle |
| Sarc/o | Soft, fleshy or connective tissue |
| Supinato/o | Forward or facing up |
| Tens/o | Stretch |
The chart below shows the suffixes related to the muscular system.
| Suffixes Related to the Muscular System | |
| -algia | Pain in fibrous tissue |
| -desis | Surgical fixation |
| -ectomy | Removal or excision by surgery |
| -gram | Record |
| -graphy | The process of recording |
| -itis | Inflammation |
| -ology | The study of |
| -oma | Mass or tumor |
| -otomy | To cut into |
| -pathy | Disease |
| -rrhapy | Suture repair |
The glossary below includes some of the more common medical terms you’ll encounter related to the musculoskeletal system and related medical conditions.
| Abduction | Drawing away from the center of the body. |
| Adduction | Drawing toward the center of the body. |
| ALS | Amyotrophic Lateral Sclerosis. Muscle disorder or atrophy with degeneration of nerves in the spinal cord and lower region of the brain. |
| Articulation | Joint |
| Atrophy | Weakening of a muscle due to lack of use. |
| Bursitis | Inflammation of the bursa sac. |
| Diathermy | Applying heat to deep tissues. |
| Dupuytren’s contracture | Disease causing the ring finger and little finger to contract toward the palm. |
| Dyskinesia | Difficult body movement. |
| Dystrophy | Abnormal development. |
| Eversion | Turning outward. |
| Extension | Movement in which a limb is placed in a straight position. |
| Fascia | Band of tissue surrounding muscle. |
| Fasciectomy | Excision of fascia. |
| Fascitis | Inflammation of fascia. |
| Flexion | Movement in which a limb is bent. |
| Fibromyalgia | Pain in tissues of muscles, tendons, or ligaments. |
| Hyperkinesia | Excessive body movement. |
| Inversion | Turning inward. |
| Kinesiology | Study of movement. |
| Leiomyoma | Benign tumor of smooth muscle. |
| Leiomyosarcoma | Malignant tumor of smooth muscle. |
| Ligament | Material that binds one bone to another. |
| Muosarcoma | Malignant tumor of muscle tissue. |
| Muscular Dystrophy | Disease characterized by progressive weakness and degeneration of muscle fibers. |
| Myalgia | Muscle pain. |
| Myasthenia | Muscle weakness. |
| Myoclonus | Relaxing and contracting a muscle in rapid succession. |
| Myology | Study of muscles. |
| Myopathy | The name for any type of muscular disease. |
| Myoplasty | Surgical repair of a muscle. |
| Myorrhapy | Suturing of a muscle. |
| Polymyalgia rheumatica | Muscle pain without arthritis or signs of muscle weakness. |
| Pronation | Movement that turns the palm of the hand downward. |
| Rotation | Turning on its own axis. |
| Supination | Movement that turns the palm of the hand downward. |
| Tendon | The connective tissue that binds muscles to bones. |
| Tennis elbow | Inflammation of the tendon that connects the arm muscle to the elbow. |
| Tenodesis | Surgical fixation of a tendon. |
| Tenodynia | Pain in a tendon. |
| Tenomyoplasty | Surgical repair of a muscle and tendon. |
| Tenorrhapy | Suturing of a tendon. |
| Tenosynovitis | Inflammation of the tendon and the sheath around it |
| Tenotomy | Incision of a tendon. |
| Torticollis | Acute myositis of the cervical muscles. |