INJURY ASSESSMENT AND MANAGEMENT

Transcription

1 INJURY ASSESSMENT AND MANAGEMENT UNIT THREE Despite the certified athletic trainer s best efforts toward injury prevention, injuries do still occur. It is important for the ATC to be able to recognize, assess, and manage injuries, both when they occur and throughout the process of rehabilitation and return to play. To have a sound understanding of injuries, the ATC must first study anatomy and physiology. The chapters that follow introduce anatomy, physiology, and the injuries most commonly encountered on the athletic field, gymnasium, or sports arena. Techniques used in the initial management and rehabilitation of those injuries are also discussed.

2 CHAPTER 14 Kinesiology abduction adduction amphiarthroses arthritis arthrology articular cartilage axial plane ball-and-socket joint bursitis circumduction KEY TERMS closed kinematic chain concave condyloid (ellipsoidal) joint convex coronal plane depression diarthroses dorsiflexion elevation eversion extension fibrocartilage flexion gliding joint gomphoses gout hinge joint hyperextension inversion joint articulation kinesiology open kinematic chain opposition osteoarthritis pivot joint plantar flexion primary fibrositis pronation protraction retraction rheumatic fever rheumatoid arthritis rotation saddle joint sagittal plane supination sutures synarthroses syndesmoses synovial fluid synovial joint synovial membrane OBJECTIVES Upon completion of this chapter, the reader should be able to: Explain the study of kinesiology Define the articular system and describe its importance to movement Define the three classifications of joints State the six types of diarthroses joints Define the 18 different movements of synovial joints Explain the three anatomical planes and their importance to medicine Explain the concept of open and closed kinematic chains 259

3 260 UNIT THREE Injury Assessment and Management kinesiology The multidisciplinary study of physical activity or movement; encompasses anatomy, biomechanics, physiology, psychomotor behavior, and social and cultural factors. DID D YOU KNOW? Careers related to the study of kinesiology include occupational and physical therapy, professional athletics, coaching, athletic training, and even nutrition. joint articulation The connecting point of two bones. arthrology The study of joints. KEY CONCEPT KINESIOLOGY The study of kinesiology focuses on exercise stress, movement efficiency, and fitness. _ Fun Facts There are more than 100 joints connecting the body s 206 bones. Kinesiology is the multidisciplinary study of physical activity or movement. It encompasses anatomy, biomechanics, physiology, psychomotor behavior, and various social and cultural factors. The study of kinesiology focuses on exercise stress, movement efficiency, and fitness. The term is fashioned from two Greek verbs, kinein and logus, which mean to move and to discourse. Modern phrasing has changed the meaning of the suffix logus to the study of, so that kinesiology reads literally as the study of movement. Kinesiology encompasses both the theory and practice of movement. The study of movement in physical activity has a long history in American higher education, in many institutions dating to the late nineteenth century. The field of study was primarily oriented to the practice of movement, such as physical training and the playing of sports. The beginning of the study of movement from a disciplinary perspective was a fragmented effort driven by the insight of a few individuals operating as individual scholars, practitioners of medicine, or aspiring academics in universities. Today, these various approaches to the study of movement all come under the single umbrella of kinesiology. This chapter addresses how the body moves, by way of its joints and related structures. ARTICULAR SYSTEM The articular system is a series of joints that allows movement of the human body. This series of joints, combined with the neuromuscular system, enables locomotion. When two bones come into contact, they form a joint articulation. Joint articulations can be freely movable, as in the knee or hip; slightly movable, as in the pubic symphysis, which moves slightly during childbirth; or immobile, as in the fused sutures of the skull. Many joints are identified by combining the names of the two bones that form the joint. An example is the sternoclavicular joint, which is the articulation between the sternum and the clavicle. The study of joints is called arthrology. CLASSIFICATION OF JOINTS Joints have two main functions. They allow motion, and at the same time provide stability. They are classified in three different ways:

4 CHAPTER 14 Kinesiology 261 KEY CONCEPT Synarthroses, or immovable Amphiarthroses, or slightly movable Diarthroses, or freely movable Synarthroses Synarthroses are joints that lack a synovial cavity and are held closely together by fibrous connective tissue. Synarthroses are immovable joints in which the bones come into very close contact and are separated only by a thin layer of fibrous connective tissue. The sutures in the skull are examples of immovable (synarthric) joints. There are three structural types of synarthroses: sutures, syndesmoses, and gomphoses. Sutures The articular system is a series of joints that allows movement of the human body. In sutures, a thin layer of dense, fibrous connective tissue unites the bones of the skull (Figure 14 1). They are immovable and fuse completely by adulthood. Sutures are found only in the skull. synarthroses (singular: synarthrosis) Immovable joints that lack a synovial cavity and are held together by fibrous connective tissue. sutures Joints where a thin layer of dense, fibrous connective tissue unites the bones of the skull. syndesmoses Slightly movable joints where bones are connected by ligaments. Syndesmoses A syndesmosis is a joint in which the bones are connected by ligaments. Examples of syndesmoses are the fibula and tibia in the lower leg (Figure 14 2), and the ulna and radius of the arm. These bones move as one when we pronate (turn or rotate the hand or forearm so that the palm faces down or back) and supinate (turn or rotate the hand or forearm so that the palm faces up or forward) the forearm, or rotate the lower leg. These joints do offer slight movement and thus are sometimes considered to be amphiarthroses. Figure 14 1 Sutures. Fibrous connective tissue Suture of skull

5 262 UNIT THREE Injury Assessment and Management Interosseous membrane Fibula Tibia Anterior tibiofibular ligament Figure 14 2 Syndesmosis. Gomphoses Gomphoses are joints in which a conical process fits into a socket and is held in place by ligaments. An example is a tooth in its alveolus (socket), held in place by the periodontal ligament (Figure 14 3). Amphiarthroses Slightly movable joints are called amphiarthroses. In this type of joint, the bones are connected by hyaline cartilage or fibrocartilage. The connections of the ribs to the sternum are slightly movable joints connected by costal hyaline cartilage. The symphysis pubis is a slightly movable joint in which there is a fibrocartilage pad between the two bones. The joints between the vertebrae are also amphiarthroses (Figure 14 4). Diarthroses or Synovial Joints Most joints in the adult body are diarthroses, or freely movable joints. In this type of joint, the ends of the opposing bones are covered with a type of hyaline cartilage gomphoses (singular: gomphosis) Immovable joints in which a conical process fits into a socket held in place by ligaments. amphiarthroses (singular: amphiarthrosis) Slightly movable joints connected by fibrocartilage. fibrocartilage Specialized connective tissue with thick collagen fibers. Socket of alveolar process Periodontal ligament Figure 14 3 Gomphosis. Root of tooth

6 CHAPTER 14 Kinesiology 263 KEY CONCEPT Vertebra Fibrocartilage Intervertebral disc Figure 14 4 Amphiarthrosis. The three classifications of joints are synarthroses, amphiarthroses, and diarthroses. The synarthroses are immovable. The amphiarthroses are slightly movable. The diarthroses are freely movable. Most joints in the human body are diarthroses joints. called the articular cartilage, and they are separated by a space called the joint cavity. The components of the joints are enclosed in a dense, fibrous joint capsule. The outer layer of the capsule consists of the ligaments that hold the bones together. The inner layer, the synovial membrane, secretes synovial fluid into the joint cavity for lubrication. Because all diarthroses joints have a synovial membrane, they are sometimes called synovial joints. There are six different types of synovial joints. Each type allows a different degree of mobility. Pivot Joint The pivot joint is a freely movable joint in which a bone moves around a central axis, creating rotational movement (Figure 14 5). An example is the joint between the radius and ulna of the lower arm. Radius Ulna Pivot diarthroses (singular: diarthrosis) Freely movable joints; also known as synovial joints. articular cartilage Connective tissue covering the ends of long bones. synovial membrane A double layer of connective tissue that lines joint cavities and produces synovial fluid. synovial fluid A lubricating substance found in joint cavities. synovial joint Freely movable joint; also known as a diarthrosis. pivot joint A freely movable joint in which a bone moves around a central axis, creating rotational movement. Figure 14 5 Pivot joint.

7 264 UNIT THREE Injury Assessment and Management gliding joint A freely movable joint that allows bones to make a sliding motion. hinge joint A freely movable joint that allows flexion and extension. concave A half-circle-shaped indentation to a surface. convex A half-circle-shaped protrusion on a surface. condyloid (ellipsoidal) joints Freely movable joints that allow bones to move about one another in many different directions, but not to rotate. ball-and-socket joints Freely movable joints in which a rounded end of one bone fits into an indented end of another bone; allows the widest range of motion. Gliding Joint A gliding joint allows bones to make a sliding motion, either back and forth or side to side. They are found in the carpals of the wrist and the tarsals of the ankle. Gliding joints are also found between the vertebrae in the spine (Figure 14 6). Hinge Joint The hinge joint allows only extension and flexion. The reason for this is that the convex surface of one bone fits into the concave surface of the second bone. The knee, elbow (Figure 14 7), and phalanges of the fingers and toes are all hinge joints. Condyloid or Ellipsoidal Joint Condyloid or ellipsoidal joints are formed where bones can move about one another in many directions, but cannot rotate. This joint is named for a condyle-containing bone. A condyle is a curved process that fits into a fossa (cavity) in another bone for its articulation. This type of joint can be found at the metacarpals (bones in the palm of the hand) and phalanges (fingers), and between the metatarsals (foot bones, excluding the heel) and phalanges (toes) (Figure 14 8). Ball-and-Socket Joint In a ball-and-socket joint, one bone has a rounded end that fits into a concave cavity on another bone. This provides the widest range of movement possible in joints; for example, the hips (Figure 14 9) and shoulders can swing in almost any direction. Convex Concave Hinge Concave surface of ulna Figure 14 6 Gliding joint. Figure 14 7 Hinge joint.

8 CHAPTER 14 Kinesiology 265 Ball-and-socket joint Figure 14 8 Condyloid joint. Figure 14 9 Ball-and-socket joint. Saddle Joint In a saddle joint, the two bones both concave and convex regions, with the shapes of the two bones complementing one another. This joint also allows a wide range of movement. The only saddle joint in the body is in the thumb (Figure 14 10). This joint allows humans to turn and oppose their thumbs in cooperation with the fingers. KEY CONCEPT The six types of diarthroses are pivot joints, gliding joints, hinge joints, condyloid or ellipsoidal joints, ball-and-socket joints, and saddle joints. Each type allows a particular type of motion. Saddle saddle joint A freely movable joint between two bones with complementary shapes; allows a wide range of motion. Figure Saddle joint.

9 266 UNIT THREE Injury Assessment and Management MOVEMENTS OF DIARTHROSES (SYNOVIAL JOINTS) flexion Movement that decreases the angle between two bones. extension Movement that increases the angle between two bones. hyperextension Movement beyond the natural range of motion. abduction Movement of the limbs away from the midline of the body. adduction Movement of the limbs toward the midline of the body. rotation Movement of a bone on an axis, toward or away from the body. circumduction Circular movement of the limbs around an axis. The range of motion in movable joints varies. Some joints are only slightly movable; others are capable of a wide range of motion. The ranges of motion of the movable joints determine the positions the human body can assume, and play an important role in athletic activity. The joints in the body that move most freely are the synovial joints. The greater the range of motion in a synovial joint, the more the joint relies on the attached muscles for stability. The joints with the greatest amount of movement are the shoulders. The hips a not-too-distant second: Some gymnasts have a range of motion in their hips nearly as great as that in their shoulders. The stability of a joint is determined by three factors: the shape of the bones where they come together, the ligaments that join the bones, and muscle tone. In some joints, the shapes of the bones are well matched, resulting in a very stable joint (such as the hips); in others the opposite is true. The more ligaments a joint possesses, the stronger it is, but joints that rely on ligaments for bracing are not very stable. For most joints, however, muscle tone is the main stabilizing factor. The shoulder and knee joints, for example, are primarily stabilized in this way. Muscle tone keeps the tendons that attach the muscles to the bones taut, reinforcing the related joints. Synovial joints allow 18 different types of movements: Flexion decreases the angle between two bones (Figure 14 11A). Extension increases the angle between two bones (Figure 14 11A). Hyperextension increases (extends)the angle between two bones beyond the normal range of motion (Figure 14 11B). Abduction describes movements of the limbs only; in abduction, the limb moves away from the midline of the body (Figure 14 11C). Adduction also describes movement of the limbs only; in adduction, the limb moves toward the midline of the body (Figure 14 11C). Rotation occurs when a bone turns on its axis toward or away from the midline of the body, in limbs, or between the atlas and axis (Figure 14 11D). Circumduction is the ability of a limb to move in a circular path around an axis. The proximal portion of the limb remains stationary, while the distal portion moves in a circle (Figure 14 11E).

10 CHAPTER 14 Kinesiology Flexion Hyperextension Forward flexion 0 Extension 50 Figure 14 11A Flexion and extension. Figure 14 11B Hyperextension. 180 Abduction Internal rotation 90 Adduction 50 Figure 14 11C Abduction and adduction. Figure 14 11D Internal rotation.

11 268 UNIT THREE Injury Assessment and Management supination Movement of the radius and ulna anterior or superior. pronation Movement of the radius and ulna posterior or inferior. plantar flexion Movement that extends the foot. dorsiflexion Movement that flexes the foot. inversion Movement of the sole of the foot inward. eversion Movement of the sole of the foot outward. protraction Movement of a body part forward in a transverse plane. retraction Movement of a body part backward in a transverse plane. elevation Movement of a body part upward in a frontal plane. Figure 14 11E Circumduction. Supination refers to the act of turning the palm upward, performed by lateral rotation of the forearm. When applied to the foot, it generally implies movements resulting in raising of the medial margin of the foot (Figure 14 11F). Pronation refers to the act of turning the palm downward, performed by medial rotation of the forearm. When applied to the foot, it generally implies movements resulting in lowering of the medial margin of the foot (Figure 14 11F). Plantar flexion extends the foot, with the toes pointing down (Figure 14 11G). Dorsiflexion flexes the foot, bringing the toes up toward the lower leg (Figure 14 11G). Inversion turns the sole of the foot inward (medially) (Figure 14 11H). Eversion turns the sole of the foot outward (laterally) (Figure 14 11H). Protraction occurs in a transverse plane, moving the body part forward (shoulders, mandible) (Figure 14 11I). Retraction also occurs in a transverse plane, moving the body part backward (Figure 14 11J). Elevation occurs in the frontal plane, lifting the body part superiorly (upward), as with the shoulders (Figure 14 11K).

12 CHAPTER 14 Kinesiology Dorsiflexion Supination 90 Pronation 0 45 Plantar flexion Figure 14 11F Supination and pronation. Figure 14 11G Plantar flexion and dorsiflexion Eversion 30 Inversion Figure 14 11H Eversion and inversion. Figure 14 11I Protraction.

13 270 UNIT THREE Injury Assessment and Management depression Movement of a body part downward in a frontal plane. opposition Movement of the thumb to touch each finger. Depression also occurs in the frontal plane, moving the body part inferiorly (downward) (Figure 14 11L). Opposition moves the thumb to touch the tips of the other fingers (Figure 14 11M). Figure 14 11J Retraction. Figure 14 11K Elevation. Figure 14 11L Depression. Figure 14 11M Opposition.

14 CHAPTER 14 Kinesiology 271 DISORDERS OF JOINTS Disorders of the joints are common. Often the reason for the disorder is excessive use or stress on the joint. This is commonly the case in athletic injuries. Other disorders are hereditary or the result of the deterioration that accompanies aging. Bursitis Bursitis is an inflammation of the synovial bursa that can be caused by excessive stress or tension placed on the bursa. For example, playing tennis for long periods of time may cause tennis elbow, which is bursitis in the elbow joint caused by excessive stress. You may experience canoeist elbow if you go canoing and paddle for long hours. This is, of course, temporary. The elbow and shoulder are common sites of bursitis. It can also be caused by a local or systemic inflammatory process. If bursitis persists, as in chronic bursitis, the muscles in the joint can eventually degenerate or atrophy, and the joint can become stiff even though the joint itself is not diseased. Arthritis Arthritis is an inflammation of the entire joint. It usually involves all the tissues of the joint: cartilage, bone, muscles, tendons, ligaments, nerves, blood supply, and so on. There are more than 100 varieties of arthritis, and 10 percent of the population experiences this disorder, which has no cure. Analgesics are commonly used for pain relief, but they affect only the symptom of arthritis (pain). Rheumatic Fever Rheumatic fever is a disease involving a bacterial infection. If undetected in childhood, the bacterium can be carried by the bloodstream to the joints, resulting in the development of rheumatoid arthritis. Rheumatoid Arthritis Rheumatoid arthritis is a connective-tissue disorder resulting in severe inflammation of small joints. It is severely debilitating and can destroy the joints of the hands and feet. The cause is unknown. A genetic factor may be involved, or an autoimmune reaction in which an immune reaction develops against a person s own tissues. The synovial membranes of the joints and connective tissues grow abnormally to form a layer in the joint capsule. This layer invades the articulating surfaces of the bone, destroying cartilage and fusing the bones of the joint. bursitis An inflammation of the synovial cavity caused by excessive stress or tension. arthritis An inflammation of an entire joint. rheumatic fever A bacterial infection that can be carried in the blood to the joints. rheumatoid arthritis A connective-tissue disorder resulting in severe inflammation of small joints.

15 272 UNIT THREE Injury Assessment and Management primary fibrositis An inflammation of the fibrous connective tissue in a joint. osteoarthritis A degenerative joint disease. gout An accumulation of uric acid crystals in the joint at the base of the large toe and other joints of the feet. Primary Fibrositis Primary fibrositis is an inflammation of the fibrous connective tissue in a joint. It is commonly called rheumatism by laypersons. If it is in the lower back, it is commonly called lumbago. Osteoarthritis Osteoarthritis, sometimes referred to as degenerative joint disease, occurs with advancing age, especially in people in their seventies. It is more common in overweight individuals and affects the weight-bearing joints. Mild exercise can prevent joint deterioration and increases the ability to maintain movement at joints. Gout Gout is an accumulation of uric acid crystals in the joint at the base of the large toe and other joints of the feet and legs. It may also present itself in other joints throughout the body. It is more common in men than in women. These waste-product crystals can also accumulate in the kidneys, causing kidney damage. ANATOMICAL PLANES In medicine, professionals refer to sections of the body in terms of anatomical planes or flat surfaces. These planes are imaginary lines, vertical or horizontal, which are drawn KEY CONCEPT Medical professionals refer to sections of the body in terms of anatomical planes or flat surfaces. The coronal plane, also known as the frontal plane, allows discussion of anatomy related to the front or back of the body. The sagittal plane allows discussion of anatomy related to the right and left halves of the body. The axial plane, also known as the transverse plane, allows discussion related to the upper or lower portion of the body. through an upright body (Figure 14 12). In the anatomical position, the human body stands erect, eyes looking forward, arms at the sides, and the palms of the hands and the toes facing forward. The following terms are used to describe the specific planes of the body. It is important to understand how these terms and principles relate to movement about or within a specific surface or plane. Table 14 1 lists additional terms used to describe anatomical direction.

16 CHAPTER 14 Kinesiology 273 Axial (transverse) plane Coronal (frontal) plane Sagittal plane Figure Anatomical planes. Table 14 1 Anatomical Terms Relating to Direction ANATOMICAL TERM Medial Lateral Proximal Distal Inferior Superior Cephalad or Cranial Caudal or Caudad Anterior Posterior DIRECTION Toward the midline of the body Away from the midline of the body Nearest to a reference point Farthest from a reference point Below Above Toward the head Toward the tailbone Toward the front Toward the back

17 274 UNIT THREE Injury Assessment and Management coronal plane A vertical flat surface running from side to side of the body; also known as the frontal plane. sagittal plane A vertical flat surface running from front to back of the body. axial plane A horizontal flat surface dividing the body into upper and lower parts; also known as the transverse plane. Coronal Plane (Frontal Plane) The coronal plane is a vertical plane running from side to side. This divides the body or any of its parts into anterior (front) and posterior (back) portions. Sagittal Plane (Lateral Plane) The sagittal plane is a vertical plane running from front to back. This divides the body or any of its parts into right and left sides. Axial Plane (Transverse Plane) The axial plane is a horizontal plane dividing the body or any of its parts into upper and lower parts. CLOSED AND OPEN KINEMATIC CHAINS closed kinematic chain A sequence of action in which the body part farthest from the trunk is fixed during movement. open kinematic chain A sequence of action in which the body part farthest from the trunk is free during movement. The concept of closed- and open-chain exercise was first discussed by Dr. Arthur Steindler, in his book titled Kinesiology of the Human Body: Under Normal and Pathological Conditions (1955). Steindler defined chains as links of body parts, such as the foot, ankle, knee, and hip. Each link has an effect on the others. An example is walking, in which the foot, ankle, knee, and hip all play an important part in forward movement. In a closed kinematic chain movement or exercise, the end of the chain farthest from the body is fixed; for example, in a squat the feet are fixed and the rest of the leg chain moves. Walking, or performing a pull-up or push-up, involve closed-chain motion. In open kinematic chain movement or exercise, the end of the chain is free, such as in a seated leg extension. Waving a hand or kicking a ball are additional examples of open-chain movements. Closed- and open-chain exercises provide different benefits. Closedchain exercises tend to emphasize compression of joints. An example is the knee during the upright stance phase of squats (Figure 14 13). Because the distal end does not move, the knee joint is more stable.

18 CHAPTER 14 Kinesiology 275 Figure During this closed-chain exercise, the feet are fixed and do not move, creating compressive forces on the skeleton. A B Figure 14 14A B In this open-chain exercise, the feet move during the exercise, creating shear forces at the knee.

19 276 UNIT THREE Injury Assessment and Management Open-chain exercises tend to involve more shearing force parallel to the joint, and therefore create a less stable condition for exercise. For example, during a leg extension the knee is never under compression forces (Figure 14 14). Closed chains tend to involve more muscles and joints than do open chains, and lead to better coordination around each structure, which improves overall stability. Trunk movements are hard to categorize as closed- or open-chain because of the difficulty in assigning proximal and distal directions within the trunk. CONCLUSION KEY CONCEPT Closed- and open-chain exercises provide different benefits. Closed-chain exercises emphasize compression of joints, whereas open-chain exercises involve shearing forces. Open-chain exercises do not provide as much stability as do closed-chain exercises. Joints allow motion while providing stability. Joints are classified as nonmovable (immobile), slightly movable, and freely movable. Besides providing stability, they allow at least 18 different movements. This creates the dexterity needed to complete a variety of complex tasks. Athletics involves movement in and around many different planes. The anatomical planes are used for reference as to the location and direction of movement. Closed- and open-chain movements and exercises provide different benefits to athletes. Closed-chain exercises provide more stability for the joints and involve more muscles and joints than do open chains. REVIEW QUESTIONS 1. What is the articular system? 2. List the three classifications of joints, including their function. 3. Give one example of where you would find a synovial joint. 4. How is the structure of the saddle joint more complex, as compared to the other synovial joints? 5. How do circumduction and rotation differ? 6. What is the purpose of anatomical planes? 7. How are the axial and sagittal planes different? 8. Who developed the concept of open- and closed-chain exercises? 9. What is the difference between an open chain and a closed chain? 10. Give one example each of a closed- and open-chain exercise. Use examples that are not shown or described in this chapter.

20 CHAPTER 14 Kinesiology 277 PROJECTS AND ACTIVITIES 1. Create a model of a synarthrosis, an amphiarthrosis, and a diarthrosis. 2. Draw an example of each of the six different types of synovial joints. 3 Using stick figures, illustrate each synovial movement. 4. Draw a model of the human body. Divide it into its anatomical planes. 5. Research open- and closed-chain exercises for repair of the anterior cruciate ligament (ACL). In a report, explain the difference between the two chains and describe when they are used in rehabilitation. LEARNING LINKS Search websites for topics on kinesiology and the various joints discussed in this chapter. Can you find additional information on programs of study or the relationship of athletics to kinesiology? Search websites for additional information on the disorders and diseases discussed in this chapter. Are there specific joint disorders that athletes tend to suffer from more than others?