Synovial joints allow the body a tremendous range of movements. Each movement at a synovial joint results from the contraction or relaxation of the muscles that are attached to the bones on either side of the articulation. The type of movement that can be produced at a synovial joint is determined by its structural type.
Overall, each type of synovial joint is necessary to provide the body with its great flexibility and mobility. There are many types of movement that can occur at synovial joints (Table 1). Movement types are generally paired, with one being the opposite of the other.
For the vertebral column, flexion (anterior flexion) is an anterior (forward) bending of the neck or body, while extension involves a posterior-directed motion, such as straightening from a flexed position or bending back ward. Lateral flexion is the bending of the neck or body toward the right or left side.
Adduction, abduction, and circumduction take place at the shoulder, hip, wrist, metacarpophalangeal, and metatarsophalangeal joints.
Circumduction. Circumduction is the movement of a body region in a circular manner, in which one end of the body region being moved stays relatively stationary while the other end describes a circle. It involves the sequential combination of flexion, adduction, extension, and abduction at a joint.
Rotation. Rotation can occur within the vertebral column, at a pivot joint, or at a ball-and-socket joint. Rotation of the neck or body is the twisting movement produced by the summation of the small rotational movements available between adjacent vertebrae. At a pivot joint, one bone rotates in relation to another bone.
The proximal radioulnar joint is a pivot joint formed by the head of the radius and its articulation with the ulna. This joint allows for the radius to rotate along its length during pronation and supination movements of the forearm.
Synovial joints allow the body a tremendous range of movements. Each movement at a synovial joint results from the contraction or relaxation of the muscles that are attached to the bones on either side of the articulation. The type of movement that can be produced at a synovial joint is determined by its structural type. While the ball-and-socket joint gives the greatest range of movement at an individual joint, in other regions of the body, several joints may work together to produce a particular movement. Overall, each type of synovial joint is necessary to provide the body with its great flexibility and mobility. There are many types of movement that can occur at synovial joints ( [link] ). Movement types are generally paired, with one being the opposite of the other. Body movements are always described in relation to the anatomical position of the body: upright stance, with upper limbs to the side of body and palms facing forward. Refer to [link] as you go through this section.
Synovial joints allow the body a tremendous range of movements. Each movement at a synovial joint results from the contraction or relaxation of the muscles that are attached to the bones on either side of the articulation. The type of movement that can be produced at a synovial joint is determined by its structural type.
Overall, each type of synovial joint is necessary to provide the body with its great flexibility and mobility. There are many types of movement that can occur at synovial joints ( [link] ). Movement types are generally paired, with one being the opposite of the other.
Adduction/abduction and circumduction take place at the shoulder, hip, wrist, metacarpophalangeal, and metatarsophalangeal joints.
For the vertebral column, flexion (anterior flexion) is an anterior (forward) bending of the neck or body, while extension involves a posterior-directed motion, such as straightening from a flexed position or bending back ward. Lateral flexion is the bending of the neck or body toward the right or left side.
Circumduction is the movement of a body region in a circular manner, in which one end of the body region being moved stays relatively stationary while the other end describes a circle. It involves the sequential combination of flexion, adduction, extension, and abduction at a joint.
Rotation. Rotation can occur within the vertebral column, at a pivot joint, or at a ball-and-socket joint. Rotation of the neck or body is the twisting movement produced by the summation of the small rotational movements available between adjacent vertebrae. At a pivot joint, one bone rotates in relation to another bone.
Nonverbal communication receives less attention than verbal communication as a part of our everyday lives. Learning more about nonverbal communication and becoming more aware of our own and others’ use of nonverbal cues can help us be better relational partners and better professionals. In addition, learning about cultural differences in nonverbal ...
Nonverbal Communication in Relational Contexts. A central, if not primary, function of nonverbal communication is the establishment and maintenance of interpersonal relationships. Further, people who are skilled at encoding nonverbal messages have various interpersonal advantages, including being more popular, having larger social networks ...
Emotional imbalances occur when one relational partner expresses too much emotion in a way that becomes a burden for the other person. Ideally, each person in a relationship is able to express his or her emotions in a way that isn’t too taxing for the other person.
For example, the “thumbs up” gesture, as we just learned, can mean “one” in mainland Europe, but it also means “up yours” in Greece (when thrust forward) and is recognized as a signal for hitchhiking or “good,” “good job / way to go,” or “OK” in many other cultures.
Bowing is a nonverbal greeting ritual that is more common in Asian cultures than Western cultures, but the head nod, which is a common form of acknowledgement in many cultures , is actually an abbreviated bow. Japan is considered a noncontact culture, which refers to cultural groups in which people stand farther apart while talking, make less eye contact, and touch less during regular interactions. Because of this, bowing is the preferred nonverbal greeting over handshaking. Bows vary based on status, with higher status people bowing the least. For example, in order to indicate the status of another person, a Japanese businessperson may bow deeply. An interesting ritual associated with the bow is the exchange of business cards when greeting someone in Japan. This exchange allows each person to view the other’s occupation and title, which provides useful information about the other’s status and determines who should bow more. Since bowing gives each person a good view of the other person’s shoes, it is very important to have clean shoes that are in good condition, since they play an important part of initial impression formation.
The United States and many northern and western European countries have a monochronic orientation to time, meaning time is seen as a commodity that can be budgeted, saved, spent, and wasted. Events are to be scheduled in advance and have set beginning and ending times. Countries like Spain and Mexico have a polychronic orientation to time. Appointments may be scheduled at overlapping times, making an “orderly” schedule impossible. People may also miss appointments or deadlines without offering an apology, which would be considered very rude by a person with a monochronic orientation to time. People from cultures with a monochronic orientation to time are frustrated when people from polychromic cultures cancel appointments or close businesses for family obligations. Conversely, people from polychromic cultures feel that US Americans, for example, follow their schedules at the expense of personal relationships (Martin & Nakayama, 2010).
Eye Contact. In general, women make more eye contact than men. As we learned, women use face-to-face body orientations in conversations more often than men, which likely facilitates more sustained eye contact. Overall, women tend to do more looking and get looked at more than men.
Synovial joints are the only joints that have a space between the adjoining bones. This space, referred to as the synovial (or joint) cavity, is filled with synovial fluid. Synovial fluid lubricates the joint, reducing friction between the bones and allowing for greater movement. The ends of the bones are covered with articular cartilage, a hyaline cartilage. The entire joint is surrounded by an articular capsule composed of connective tissue. This allows movement of the joint as well as resistance to dislocation. Articular capsules may also possess ligaments that hold the bones together. Synovial joints are capable of the greatest movement of the three structural joint types; however, the more mobile a joint, the weaker the joint. Knees, elbows, and shoulders are examples of synovial joints. Since they allow for free movement, synovial joints are classified as diarthroses.
In hinge joints, the slightly-rounded end of one bone fits into the slightly-hollow end of the other bone. In this way, one bone moves while the other remains stationary, similar to the hinge of a door. The elbow is an example of a hinge joint. The knee is sometimes classified as a modified hinge joint.
Condyloid joints consist of an oval-shaped end of one bone fitting into a similarly oval-shaped hollow of another bone. This is also sometimes called an ellipsoidal joint. This type of joint allows angular movement along two axes, as seen in the joints of the wrist and fingers, which can move both side to side and up and down.
The formation of hard nobs at the middle finger joints (known as Bouchard’s nodes) and at the farther away finger joint (known as Heberden’s node) are a common feature of Osteoarthritis in the hands.
Classification of Joints on the Basis of Structure and Function. The point at which two or more bones meet is called a joint or articulation. Joints are responsible for movement (e.g., the movement of limbs) and stability (e.g.,the stability found in the bones of the skull).
The point at which two or more bones meet is called a joint or articulation. Joints are responsible for movement (e.g., the movement of limbs) and stability (e.g.,the stability found in the bones of the skull). There are two ways to classify joints: on the basis of their structure or on the basis of their function.
There are two ways to classify joints: on the basis of their structure or on the basis of their function. The structural classification divides joints into fibrous, cartilaginous, and synovial joints depending on the material composing the joint and the presence or absence of a cavity in the joint.