Introduction to the Muscular System

When most people think of muscles, they think of the muscles that move our arms and legs. These are called skeletal muscles because they move the skeleton. However, there are two additional types of muscles, including smooth muscle and the cardiac muscle. The basic function of all types of muscle is to create movement.

This chapter will review common word components related to the muscular system to assist learners in analyzing, building, and defining medical terms. Other terms, whose definitions cannot be easily built from word components, will be described in context based on the anatomy and physiology of the muscular system and common diseases and disorders. Medical specialists, diagnostic tests, and procedures related to the muscular system will also be discussed.

References

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CrashCourse. (2015, June 15). Muscles, Part 2 - Organismal level: Crash Course Anatomy & Physiology #22 [Video]. YouTube. All rights reserved. https://www​.youtube.com​/watch?v=I80Xx7pA9hQ ↵.

Prefixes Related to the Muscular System

• a-: Absence of, without
• ab-: Away from
• ad-: Towards
• brady-: Slow
• dys-: Painful, difficult, abnormal, labored
• hyper-: Above, excessive
• inter-: Between
• intra-: Within, in
• poly-: Many, much
• sub-: Below, under
• supra-: Above
• sym-: Together, joined
• syn-: Together, joined

Word Roots With a Combining Vowel Related to the Muscular System

• ankyl/o: Stiff or bent
• electr/o: Electricity; electrical activity
• fasci/o: Fascia
• fibr/o: Fibrous connective tissue
• kinesi/o: Movement, motion
• kyph/o: Hump
• lamin/o: Lamina (thin, flat plate or layer)
• leimy/o: Smooth (visceral)muscle that lines the walls of internal organs
• my/o: Muscle
• myel/o: Spinal cord, bone marrow
• myos/o: Muscle
• myocardi/o: Heart muscle
• plant/o: Sole of the foot
• rhabd/o: Rod-shaped, striated
• sarc/o: Flesh, connective tissue
• ten/o: Tendon
• tend/o: Tendon
• tendin/o: Tendon

Suffixes Related to the Muscular System

• -ad: Toward
• -al: Pertaining to
• -algia: Pain
• -ar: Pertaining to
• -asthenia: Weakness
• -centesis: Surgical puncture to aspirate fluid
• -desis: Surgical fixation, fusion
• -ectomy: Excision, surgical removal, cutting out
• -gram: The record, radiographic image
• -graphy: Process of recording, radiographic imaging
• -ic: Pertaining to
• -itis: Inflammation
• -lysis: Loosening, separating, dissolution
• -oid: Resembling
• -oma: Tumor
• -osis: Abnormal condition
• -penia: Abnormal reduction
• -physis: Growth
• -plasty: Surgical repair
• -rrhaphy: Suturing, repairing
• -sarcoma: Malignant tumor
• -schisis: Split, fissure
• -scopy: Process of viewing, visual examination
• -tome: Instrument used to cut
• -tomy: Incision, cut into
• -trophy: Nourishment, development

Smooth Muscle

Smooth muscle (SMŎŎTH MŬS-ăl) is responsible for involuntary muscle movement. Smooth muscle is present in the following areas[3]:

• Walls of hollow organs, like the urinary bladder, uterus, stomach, and intestines, where muscle contractions cause the movement of fluids and other substances
• Walls of passageways, such as the arteries and veins of the circulatory system, where it causes vasodilation and vasoconstriction
• Tracts of the respiratory, urinary, and reproductive systems, where contraction and relaxation affect the movement of air, urine, and reproductive fluids
• Eyes, where it functions to change the size of the pupil
• Skin, where it causes hair to stand erect in response to cold temperature or fear, commonly called goose bumps

Cardiac Muscle

Cardiac muscle (KÄR-dē-ăk MŬS-ăl) is only found in the heart. Highly coordinated contractions of cardiac muscle pump blood throughout the circulatory system. Cardiac muscle fiber cells are extensively branched and connected to one another at their ends to allow the heart to contract in a wavelike pattern and work as a pump.[4]

Skeletal Muscle

Skeletal muscles (SKĔL-ĕ-tăl MŬS-ălz) are located throughout the body. They are under voluntary control and primarily produce movement of the arms, legs, back, and neck and maintain posture by resisting gravity. Small, constant adjustments of the skeletal muscles are needed to hold the body upright or balanced in any position.[5]

Skeletal muscles also have several additional functions. Ring-shaped skeletal muscles called sphincters are located throughout the body at the openings of internal tracts to control the movement of substances. These skeletal muscles allow voluntary control of functions such as swallowing, defecation, and urination in the digestive and urinary systems.[6]

Skeletal muscles, such as the rectus abdominus, protect internal organs (particularly abdominal and pelvic organs) by acting as an external barrier against trauma and supporting the weight of the organs.[7]

Skeletal muscles also contribute to maintaining homeostasis by generating heat. This heat generation is very noticeable during exercise, when sustained muscle movement causes a person’s body temperature to rise, or conversely during cold environmental temperatures when shivering produces random skeletal muscle contractions to generate heat.[8]

See Figure 14.2[9] for an illustration of the major skeletal muscles of the body. For the anterior and posterior views in this figure, superficial muscles are shown on the right side of the body, and deep muscles are shown on the left side of the body. For the legs, superficial muscles are shown in the anterior view while the posterior view shows both superficial and deep muscles.[10]

Figure 14.2

Muscular System

Muscles are named based on various characteristics, such as the following[11]:

• Body location: The area of the body, for example, biceps, triceps, and quadriceps
• Size: The size of the muscle, such as maximus (largest) and minimus (smallest)
• Shape: The shape of the muscle, such as deltoid (triangular) or trapezius (trapezoid)
• Action: The action of the muscle, such as flexor (i.e., to flex) or adductor (i.e., towards midline of body)
• Fiber direction: The direction of the muscle fibers (such as external oblique)

Tendons

Muscles attach to bones via tendons (TĔN-dŏnz). A tendon is a flexible but inelastic cord of strong fibrous collagen tissue. For example, consider the Achilles tendon, hamstring, and rotator cuff. The Achilles tendon (ə-KĬL-ēz TĔN-dŏn) attaches the calf muscles to the heel bone. The hamstring (HĂM-strĭng) tendons refer to five tendons at the back of a person’s knee that connect a group of three hamstring muscles to bones in the pelvis, knee, and lower leg. The rotator cuff (rō-TĀ-tŏr KŬF) is a group of muscles and tendons that stabilize the shoulder.[13] See Figure 14.3[14] for an illustration of the tendon that attaches the quadriceps muscle to the top of the patella.

Figure 14.3

Tendon

References

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“Types_Of_Muscle​.jpg” by www​.scientificanimations.com is licensed under CC BY-SA 4.0 ↵.

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This work is a derivative of Anatomy and Physiology by OpenStax licensed under CC BY 4.0. Access for free at https://openstax​.org​/books/anatomy-and-physiology​/pages/1-introduction ↵.

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This work is a derivative of Anatomy and Physiology by OpenStax licensed under CC BY 4.0. Access for free at https://openstax​.org​/books/anatomy-and-physiology​/pages/1-introduction ↵.

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This work is a derivative of Anatomy and Physiology by OpenStax licensed under CC BY 4.0. Access for free at https://openstax​.org​/books/anatomy-and-physiology​/pages/1-introduction ↵.

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This work is a derivative of Anatomy and Physiology by OpenStax licensed under CC BY 4.0. Access for free at https://openstax​.org​/books/anatomy-and-physiology​/pages/1-introduction ↵.

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This work is a derivative of Anatomy and Physiology by OpenStax licensed under CC BY 4.0. Access for free at https://openstax​.org​/books/anatomy-and-physiology​/pages/1-introduction ↵.

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This work is a derivative of Anatomy and Physiology by OpenStax licensed under CC BY 4.0. Access for free at https://openstax​.org​/books/anatomy-and-physiology​/pages/1-introduction ↵.

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“1105​_Anterior_and_Posterior​_Views_of_Muscles.jpg” by OpenStax is licensed under CC BY 4.0 ↵.

10.

This work is a derivative of Anatomy and Physiology by OpenStax licensed under CC BY 4.0. Access for free at https://openstax​.org​/books/anatomy-and-physiology​/pages/1-introduction ↵.

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This work is a derivative of Anatomy and Physiology by OpenStax licensed under CC BY 4.0. Access for free at https://openstax​.org​/books/anatomy-and-physiology​/pages/1-introduction ↵.

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This work is a derivative of Anatomy and Physiology by OpenStax licensed under CC BY 4.0. Access for free at https://openstax​.org​/books/anatomy-and-physiology​/pages/1-introduction ↵.

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This work is a derivative of Anatomy and Physiology by OpenStax licensed under CC BY 4.0. Access for free at https://openstax​.org​/books/anatomy-and-physiology​/pages/1-introduction ↵.

14.

“Quadriceps_tendon​.svg” by InjuryMap is licensed under CC BY-SA 4.0 ↵.

References

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This work is a derivative of Anatomy and Physiology by OpenStax licensed under CC BY 4.0. Access for free at https://openstax​.org​/books/anatomy-and-physiology​/pages/1-introduction ↵.

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“Body_Movements_I​.jpg” by Tonye Ogele CNX is licensed under CC BY-SA 3.0 ↵.

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“Body_Movements_II​.jpg” by Tonye Ogele CNX is licensed under CC BY-SA 3.0 ↵.

4.

RegisteredNurseRN. (2021, March 3). Flexion and extension anatomy: Shoulder, hip, forearm, neck, leg, thumb, wrist, spine, finger [Video]. YouTube. All rights reserved. Reused with permission. https://www​.youtube.com​/watch?v=p4xbehGmkmk ↵.

5.

RegisteredNurseRN. (2021, March 29). Abduction and adduction of wrist, thigh, fingers, thumb, arm | Anatomy body movement terms [Video]. YouTube. All rights reserved. Reused with permission. https://www​.youtube.com​/watch?v=qcxE9uql8g4 ↵.

6.

RegisteredNurseRN. (2021, January 11). Inversion and eversion of the foot, ankle | Body movement terms anatomy [Video]. YouTube. All rights reserved. Reused with permission. https://www​.youtube.com​/watch?v=4HuxLWQykxk ↵.

7.

RegisteredNurseRN. (2020, December 29). Dorsiflexion and plantar flexion of the foot | Anatomy body movement terms [Video]. YouTube. All rights reserved. Reused with permission. https://www​.youtube.com​/watch?v=e6WugOzgFIM ↵.

8.

Dr Matt & Dr Mike. (2021, February 7). Joint movements [Video]. YouTube. All rights reserved. https://www​.youtube.com​/watch?v=tAJjXvumL7E ↵.

Cerebral Palsy

Cerebral palsy (sĕr-Ē-brăl pôl-zē) (CP) is a group of disorders that affects the ability to move and maintain balance and posture. CP is the most common motor disability in childhood. “Cerebral” means having to do with the brain, and “palsy” means weakness or problems with using the muscles. CP is caused by abnormal brain development or damage to the developing brain that affects the ability to control muscles.[1]

The symptoms of CP vary from person to person. A person with severe CP might require the use of special equipment to walk or might not be able to walk at all and need lifelong care. A person with mild CP, on the other hand, might walk a little awkwardly, but otherwise not require specialized care. Doctors classify CP according to the main type of movement disorder involved. Depending on which areas of the brain are affected, one or more of the following movement disorders can occur[2]:

• Spasticity (spăs-TĬS-ĭ-tē): Stiff muscles
• Dyskinesia (dĭs-kĭ-NĒ-zē-ă): Uncontrollable movements
• Ataxia (ă-TĂK-sē-ă): Poor balance and coordination

There is no cure for CP, but treatment can improve the quality of life for people who have the condition. After CP is diagnosed, a team of health professionals works with the child and family to develop a plan to help the child reach their optimal potential. Common treatments include medications; surgery; braces; and physical, occupational, and speech therapy.[3]

See Figure 14.6[4] for an image of David Smith who has cerebral palsy and has won several Paralympian awards. Paralympians are athletes with a range of impairments who compete in the Paralympics, a competition similar to the Olympics. Paralympic athletes inspire people around the world with their performance and focus on moving forward and never giving up.[5]

Figure 14.6

David Smith, a Paralympian With Cerebral Palsy

Contracture

A contracture (kŏn-TRĂK-chŭr) is a condition of shortening and hardening of muscles, tendons, or other tissue, often leading to deformity and rigidity of joints. Contractures are caused by immobility and can be the result of several disorders such as a stroke, cerebral palsy, or muscular dystrophy. Contractures may be prevented and/or treated with braces, physical therapy, and range-of-motion exercises. See Figure 14.7[6] for an image of a hand contracture.

Figure 14.7

Hand Contracture

Fibromyalgia

Fibromyalgia (fī-brō-mī-AL-jē-ă) is defined as pain in muscle fibers. It is a condition that causes widespread pain, sleep problems, fatigue, and often emotional distress. Fibromyalgia affects about 2% of the adult population in the United States. The cause of fibromyalgia is not known, but it can be effectively treated and managed. Fibromyalgia is diagnosed by health care providers based on the patient’s history, physical examination, X-rays, and blood work.[7]

Fibromyalgia is treated by a doctor or team of health care professionals who specialize in the treatment of fibromyalgia. A combination of treatments is typically prescribed, which may include the following[8]:

• Medications, including prescription drugs and over-the-counter pain relievers
• Aerobic exercise and muscle strengthening exercise
• Patient education classes
• Stress management techniques such as meditation, yoga, and massage
• Good sleep habits to improve the quality of sleep
• Cognitive behavioral therapy, a type of talk therapy that helps people change the way they think about their life circumstances

Muscular Dystrophy

Muscular dystrophy (mŭs’kyŭ-lăr DĬS-trŏ-fē) (MD) refers to group of diseases caused by abnormal muscle development due to gene mutations. Muscular dystrophy can run in families, or a person can be the first in their family to have muscular dystrophy. Over time, muscle weakness decreases mobility and makes it difficult to perform everyday tasks. There are many types of muscular dystrophy, each affecting specific muscle groups. Each type has signs and symptoms that appear at different ages and vary in severity.[9]

An example of one type of MD is Duchenne muscular dystrophy (DMD), a genetic disorder characterized by progressive muscle degeneration and weakness due to the alterations of a muscle protein called dystrophin. DMD symptom onset is in early childhood, usually between the ages 2 and 3. The disease primarily affects boys. Muscle weakness is the principal symptom of DMD and begins by first affecting the proximal muscles (those closest to the core of the body) and later affecting the distal limb muscles. The child with DMD might have difficulty jumping, running, and walking. Other symptoms include enlargement of the calves, a waddling gait, and lumbar lordosis (an inward curve of the spine). The heart and respiratory muscles are affected as well. Progressive weakness and scoliosis result in impaired pulmonary function, which can eventually cause acute respiratory failure. Treatment of DMD requires multidisciplinary care to coordinate specialized assessments and interventions needed to maximize function and quality of life. Due to recent advances in cardiology and pulmonology, people with DMD are living longer than ever and often well into adulthood.[10]

The impact of DMD can be significantly minimized by keeping the body as flexible, upright, and mobile as possible. As muscle deteriorates, a person with muscular dystrophy often develops contractures. If not treated, contractures can become severe, causing discomfort and restricting mobility and flexibility. Contractures can affect the knees, hips, feet, elbows, wrists, and fingers. However, there are many ways to minimize and postpone contractures. Range-of-motion exercises, performed on a regular schedule, help delay contractures by keeping tendons from shortening prematurely. Braces on the lower legs also can help keep the limbs stretched and flexible, delaying the onset of contractures. Eventually, a wheelchair is needed, typically by about age 12. Although a child and parents may dread using a wheelchair, many people find that when they start to use one, they are more mobile, energetic, and independent than when trying to walk without assistance.[11] See Figure 14.8[12] for an image of child with MD using a specialized wheelchair called an “Easy Stand” that supports him while sitting and also allows him to stand for periods of time.

Figure 14.8

Child With MD in an EasyStand Wheelchair

Myasthenia Gravis

Myasthenia gravis (mī-ăs-THĒ-nē-ă GRĂ-vĭs) (MG) is a chronic, autoimmune neuromuscular disease that causes weakness in voluntary muscles, including those required for breathing and swallowing. Onset of symptoms can be rapid and include the following[13]:

• Myasthenia (mī-ăs-THĒ-nē-ă): Abnormal weakness of voluntary muscles
• Ocular myasthenia (Ō-kyŭ-lăr mī-ăs-THĒ-nē-ă): Weakness of the eye muscles
• Ptosis (TŌ-sĭs): Drooping of one or both eyelids (See Figure 14.9[14] for an image of ptosis.)
• Diplopia (dĭ-PLŌ-pē-ă): Blurred or double vision
• Dysphagia (dĭs-FĀ-jē-ă): Difficulty swallowing
• Dyspnea (dĭsp-NĒ-ă): Shortness of breath
• Dysarthria (dĭs-ĂR-thrē-ă): Impaired speech

Figure 14.9

Ptosis Related to Myasthenia Gravis

Sometimes the muscles that control breathing weaken to the point where a person needs a ventilator to breathe. This is called a myasthenic crisis and requires immediate emergency medical care. A myasthenic crisis may be triggered by infection, stress, surgery, or an adverse reaction to medication.[15]

MG is diagnosed by health care providers based on a physical exam, blood tests, and electromyography (EMG). Read more about EMG in the “Medical Specialists, Diagnostic Testing, and Procedures Related to the Muscular System” section. MG is treated with medications that improve neuromuscular transmission and increase muscle strength. Immunosuppressive medications may be prescribed to impact the autoimmune response. In some cases, a thymectomy (i.e., removal of the thymus) may be performed to rebalance the immune system and decrease MG symptoms.[16]

Paralysis

Paralysis (păr-ă-LĪ-sĭs) occurs when an injury or medical condition disrupts the nerve signals to the muscles, resulting in being unable to make voluntary movements. Common causes of paralysis include spinal cord injuries and strokes. Paralysis can be localized, where it affects specific areas of the body, such as the face. For example, Bell’s palsy temporarily paralyzes facial muscles. Paralysis can also be generalized where it affects a larger area of the body. There are categories of generalized paralysis based on its extent. Common categories include hemiplegia, paraplegia, and quadriplegia/tetraplegia[17]

• Hemiplegia (hĕm-ē-PLĒ-jē-ă): Paralysis affects one side of the body, for example, an arm and a leg on the same side.
• Paraplegia (păr-ă-PLĒ-jē-ă): Paralysis affects both legs and sometimes the torso.
• Quadriplegia or Tetraplegia (kwŏd-rĭ-PLĒ-jē-ă or tĕt-ră-PLĒ-jē-ă): Paralysis involves all limbs, with little or no movement from the neck down.

See Figure 14.10[18] for an illustration of paraplegia, hemiplegia, and tetraplegia (quadriplegia), where pink indicates the area of muscle paralysis. Because muscle paralysis is caused by disruption of nerve signals, the cervical (C), thoracic (T), and lumbar (L) nerves are labelled in the image.

Figure 14.10

Paraplegia, Hemiplegia, and Tetraplegia (Quadriplegia)

Paralysis is also classified by its effect on muscles in terms of being flaccid or spastic[19]:

• Flaccid (FLĂS-ĭd): The muscles atrophy (ĂT-rŏ-fē) (i.e., shrink) due to loss of function.
• Spastic (spăs-TĬK): The muscles tighten, causing uncontrollable jerks and spasms.

There is no cure for permanent paralysis caused by spinal nerve damage because the spinal cord can’t heal itself. However, rehabilitative services like physical and occupational therapy can help people with paralysis live independently and enjoy quality of life. Equipment used for rehabilitative/restorative care may include the following[20]:

• Adaptive equipment (ă-DĂP-tĭv ĭ-KWĬP-mĕnt): Equipment that allows people to feed themselves or drive.
• Assistive equipment (ă-SĬS-tĭv ĭ-KWĬP-mĕnt): Equipment that enhances mobility, such as wheelchairs, scooters, crutches, and canes.
• Orthotic/prosthetic devices (ŏr-THŎT-ĭk/prŏs-THĔT-ĭk dĭ-VĪS-ĕz): Devices that support the limbs and prevent contractures, such as braces.
• Voice-activated technology (vois-ăk-TĬV-ā-tĕd tĕk-NŎL-ŏ-jē): Technology that doesn’t require the need for touch or movement, such as computers, lighting systems, and phones.

See Figure 14.11[21] for an image of Mark Manion, founder of “Mark Speaks Out.” Mark was permanently disabled during a cross-country biking trip when he was struck by a drunk driver. He travels the country educating and inspiring audiences on how he has effectively coped with his life circumstances.

Figure 14.11

Mark Manion

Rhabdomyolysis

Rhabdomyolysis (rab-dō-mī-OL-ĭ-sĭs) refers to the breakdown of muscles that causes damage to the kidney. When muscle is damaged, a protein called myoglobin (mī-Ō-glŏ-bĭn) is released into the bloodstream and is filtered out of the body by the kidneys. Myoglobin breaks down into substances that damage kidney cells.[22] See Figure 14.12[23] for an illustration of rhabdomyolysis.

Figure 14.12

Rhabdomyolysis

Rhabdomyolysis may be caused by injury or any other condition that damages skeletal muscle. Potential causes of rhabdomyolysis include the following conditions[24]:

• Trauma or crush injuries
• Use of drugs such as cocaine, amphetamines, statins, heroin, or phencyclidine (PCP)
• Genetic muscle diseases
• Extremes of body temperature
• Ischemia or death of muscle tissue
• Low phosphate levels
• Seizures or muscle tremors
• Severe exertion, such as marathon running or calisthenics
• Lengthy surgical procedures
• Severe dehydration

Symptoms of rhabdomyolysis include dark, red, or cola-colored urine; decreased urine output; weakness; and myalgia (mī-AL-jē-ă) (i.e., muscle pain). Rhabdomyolysis is diagnosed with blood tests, including creatine kinase (CK), myoglobin, and creatinine, as well as urine tests such as urinalysis and urine myoglobin. Rhabdomyolysis is treated with intravenous fluids that contain bicarbonate. In cases causing severe kidney damage, dialysis may be required.[25]

Strain

A strain (strān) is an injury to a muscle or tendon from being overstretched or torn, causing pain. Strains can be caused by an injury, overusing a muscle, or using a muscle in the wrong way (such as twisting the back while lifting a heavy object). A strain is different from a sprain (sprān), which is an injury to a joint when a ligament is stretched or torn. See Figure 14.13[26] for an illustration of a muscle strain and tear. Initial treatments for strains and sprains are similar and can be easily recalled by the mnemonic called RICE, which stands for the following[27]:

Figure 14.13

Strain

• Rest: Rest the strain or sprain for at least 24 hours. The health care provider may recommend not putting any weight on the injured area for 48 to 72 hours, so crutches may be needed for lower extremity injuries.
• Ice: Apply ice as soon as possible after the injury to reduce swelling. The ice should not be applied directly to the skin but should be wrapped in a cloth to avoid tissue injury. Ice should be applied for 5 to 20 minutes, four to eight times a day, for the first 48 hours or until swelling improves.
• Compression: Compress the area with an elastic wrap or bandage to reduce swelling.
• Elevate: Elevate the injured limb above your heart whenever possible to help prevent or limit swelling.

Tendonitis

Tendonitis (ten-dŏ-NĪT-ĭs) refers to inflammation of a tendon, causing pain around a joint. Tendonitis usually happens after repeated injury to an area such as the wrist or ankle. Common forms of tendonitis are named after the sports that increase their risk, such as tennis elbow, golfer’s elbow, pitcher’s shoulder, swimmer’s shoulder, and jumper’s knee. Health care providers diagnose tendonitis based on medical history, a physical exam, and possible imaging tests. Initial treatment is focused on reducing pain and swelling with RICE (rest, ice, compression, and elevation). Other treatments may include ultrasound, physical therapy, steroid injections, and surgery in severe cases.[28]

References

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Centers for Disease Control and Prevention. (2023, October 6). What is cerebral palsy? https://www​.cdc.gov/ncbddd/cp/facts.html ↵.

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Cleveland Clinic. (2021, June 10). Paralysis. https://my​.clevelandclinic​.org/health/diseases​/15345-paralysis ↵.

20.

Cleveland Clinic. (2021, June 10). Paralysis. https://my​.clevelandclinic​.org/health/diseases​/15345-paralysis ↵.

21.

“USMC-100519-M-3215R-002.jpg” by unknown author for United States Marine Corps is licensed in the Public Domain ↵.

22.

A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2023. Rhabdomyolysis; [reviewed 2021, Jul 27; cited 2023, Nov 28). https://medlineplus​.gov​/ency/article/000473.htm ↵.

23.

“Rhabdo​.jpg” by AquapatMedia is licensed under CC BY-SA 3.0 ↵.

24.

A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2023. Rhabdomyolysis; [reviewed 2021, Jul 27; cited 2023, Nov 28). https://medlineplus​.gov​/ency/article/000473.htm ↵.

25.

A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2023. Rhabdomyolysis; [reviewed 2021, Jul 27; cited 2023, Nov 28). https://medlineplus​.gov​/ency/article/000473.htm ↵.

26.

“Calf​_muscle_strain_and_tear.svg” by InjuryMap is licensed under CC BY-SA 4.0 ↵.

27.

Mayo Clinic. (2022, March 22). Sprain: First aid. https://www​.mayoclinic​.org/first-aid/first-aid-sprain​/basics/art-20056622 ↵.

28.

MedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); [updated 2022, Apr. 4]. Tendinitis; [cited 2017, Mar. 16]. https://medlineplus​.gov/tendinitis.html ↵.

Medical Specialists

There are several types of health care professionals who help treat muscular disorders and diseases and help patients achieve optimal independence and quality of life.

Diagnostic Testing

Common diagnostic tests for muscular disorders include electromyograms, magnetic resonance imaging (MRI), and range-of-motion testing.

Electromyogram

An electromyogram (ē-lĕk-trō-mī-Ŏ-grăm) (EMG) is a diagnostic procedure that assesses the function of nerve cells that control muscles. Electrodes, either attached to the skin or inserted into the muscle, record electrical impulses. An EMG can identify functional problems with the peripheral nerves, muscles, or with the signals between the nerves and the muscles. During a needle EMG, a needle electrode inserted directly into a muscle records the electrical activity in that muscle. A nerve conduction study, another part of an EMG, uses surface electrodes applied to the skin to measure the speed and strength of signals traveling between two or more points. EMG results are used to diagnose muscle and nerve disorders.[9] See Figure 14.14[10] for an image demonstrating the basics of an EMG.

Figure 14.14

Electromyography

Magnetic Resonance Imaging

Magnetic resonance imaging (măg-NĔT-ĭk rĕz-ŏ-năns ĬM-ă-jĭng) (MRI) uses radio frequency waves and a strong magnetic field to produce three-dimensional, detailed anatomical images. MRIs are often used for diagnosis and monitoring of muscular and neurological disorders. To obtain an MRI image, a patient is placed inside a large magnet and must remain very still during the imaging process in order not to blur the image. Contrast agents may be intravenously administered to a patient before or during the MRI to enhance the image. MRIs differ from computed tomography (CT) in that they do not use the ionizing radiation of X-rays. The brain, spinal cord and nerves, muscles, ligaments, and tendons are seen much more clearly with MRI than with regular X-rays and CT. For this reason, an MRI is often used to image knee and shoulder injuries. However, people with metal implants, such as pacemakers, vagus nerve stimulators, implantable cardioverter-defibrillators, loop recorders, insulin pumps, cochlear implants, deep brain stimulators, and capsules from capsule endoscopy, should not enter an MRI machine.[11] See Figure 14.15[12] for an image of an MRI machine.

Figure 14.15

Magnetic Resonance Imaging (MRI) Machine

Range of Motion

Range-of-motion testing (rānj ŏv mō-shŏn tĕs-tĭng) (ROM) is a diagnostic procedure performed by a trained health care professional that is used to determine the amount of movement around a patient’s specific joint. See Figure 14.16[13] for an image of a child undergoing range-of-motion testing of the shoulder.

Figure 14.16

Range-of-Motion Testing of the Shoulder

ROM exercises are used to treat musculoskeletal disorders and prevent contractures. Active range of motion (ăk-tĭv rānj ŏv mō-shŏn) (AROM) refers to joint movements the person can independently achieve when their opposing muscles contract and relax. Passive range of motion (păs-ĭv rānj ŏv mō-shŏn) (PROM) refers to joint movements that occur when an outside force, such as a therapist, causes movement of a patient’s joint.

Procedures

Surgical procedures related to the muscular system include tenomyoplasty, tenorrhaphy, and myorrhaphy. Tenomyoplasty (tĕn-ō-MĪ-ō-plăs-tē) refers to surgical repair of a tendon and muscle. Tenorrhaphy (tĕn-OR-ă-fē) refers to suturing of a tendon. Myorrhaphy (mī-OR-ă-fē) refers to suturing of a muscle.

References

1.

American Academy of Orthopaedic Surgeons. (n.d.). Orthopaedic surgeons: Restoring mobility and keeping our nation in motion. https://www​.aaos.org​/about/what-is-an-orthopaedic-surgeon ↵.

2.

American Academy of Neurology. (n.d.). What is a neurologist? https://www​.aan.com/tools-and-resources​/medical-students​/careers-in-neurology​/what-is-a-neurologist ↵.

3.

American Kinesiology Association. (n.d.) About AKA. https:​//americankinesiology.org ↵.

4.

American Occupational Therapy Association. (n.d.). What is occupational therapy? https://www​.aota.org/about/what-is-ot ↵.

5.

American Occupational Therapy Association. (n.d.). What is occupational therapy? https://www​.aota.org/about/what-is-ot ↵.

6.

American Physical Therapy Association. (n.d.). Careers in physical therapy. https://www​.apta.org​/your-career/careers-in-physical-therapy ↵.

7.

American Physical Therapy Association. (n.d.). Careers in physical therapy. https://www​.apta.org​/your-career/careers-in-physical-therapy ↵.

8.

American Chiropractic Association. (n.d.). Origins and history of chiropractic. https://www​.acatoday​.org/about/history-of-chiropractic ↵.

9.

Mayo Clinic. (2019, May 21). Electromyography (EMG). https://www​.mayoclinic​.org/tests-procedures​/emg/about/pac-20393913 ↵.

10.

“Electromyography​.png” by PRATYUSH AGRAWAL is licensed under CC BY-SA 4.0 ↵.

11.

National Institute of Biomedical Imaging and Bioengineering. (n.d.). Magnetic resonance imaging (MRI). National Institutes of Health. https://www​.nibib.nih​.gov/science-education​/science-topics/magnetic-resonance-imaging-mri ↵.

12.

“Scan_MRI​.jpg” by liz west from Boxborough, MA is licensed under CC BY 2.0 ↵.

13.

“New​_Horizons_2012_in​_Peru_120621-F-HI762-602.jpg” by Master Sgt. Kelly Ogden, United States Air Force is licensed in the Public Domain ↵.