Anatomy 231 Chapter 9 joints study guide

Name all the movements that occur at these joints: (a) Elbow, (b) Hip, (c) Ankle, (d) Atlantoaxial joint, (e) metacarpophalangeal joint

(a) flexion and extension, (b) flexion and extension, abduction/adduction, medical and lateral rotation, and circumduction. (C) dorsiflexion and plantar flexion occur at the ankle. (D) rotation occurs at the atlantoaxial joint, as in turning your head to say "no". (E) the metacarpophalangeal joint can produce flexion/extension, abduction/adduction, and circumduction.

Classify each of the joints named in question 6 according to joint shape. For each joint, indicate whether it is uniaxial, biaxel, or multi axel.

(a) the elbow is uniaxial hinge joint. (B) the hip is a multiracial ball and socket joint. (C) the ankle is a uniaxial hinge joint. (D) the atlantoaxial joint is a uniaxial pivot joint. (E) the metacarpophalangeal joint is a biaxial condylar joint.

are found in a symphysis joint? What types of cartilage Name one location of this type of joint.

A symphysis joint contains both hyaline cartilage, which covers the articukat joint surfaces, and fibrocartilage, which unites adjoining bones, symphysis joints are found between the vertebral bodies ( intervertebral discs) and joining the pubic bonee (pubic symphysis)

Define each of the following terms: synarthrosis, syndesmosis, synchondrosis. Which of these terms functional classification of joints?

A synarthrosis is an immovabke joint. This is a functional joint classification. A syndesmosis is a fibrous joint where the adjoining bones are connected exclusively by ligaments. A synchondrosis is a cartliaginous joint where hyaline cartilage unites adjoining bones. Both syndesmosis and synchondrosis are considered structural classifications.

How does an articular disc differ from articular cartilage?

An articular disc is composed of fibrocartilage, and it is located within the joint cavity. Articular cartilage is composed of hyaline cartilage and covers adjoining surfaces of all synovial joints.

Define pronation and supination. At which joints do these movements occur?

Pronation is medial rotation of the forearm such that the palm faces posteriorly; supination is lateral rotation of the forearm such that the palm faces anteriorly. This movement occurs at the proximal and distal radioulnar joint.

What are the functions of synovial fluid?

Synovial fluid nourishes the cells of the articular cartilage and lubricates the joint surfaces

Both the sternoclavicular and temporomandibular joints contain an articular disc. What is the function of this disc in each of these joints?

The articular disc in the sternoclavicular and the temporomandibular joints divide each joint cavity and enable multiple complex movements of each joint.

Of the shoulder, elbow, or wrist, which joint is the most stable? Which is the least stable?

The elbow is the most stable, and the shoulder is the least stable.

Which other joints described in this chapter contains an articular disc?

The knee also contains an articular disc

The articular surfaces of the knee contribute little to the stability of this joint. What additional structural features aid in stabilizing the knee?

The medial and lateral menisci of the knee aid in joint stability, as do the extensive capsular, extracapsular, and intracapsular ligaments. Muscle tone in the quadriceps and hamstrings muscles also contribute to stability of the knee.

What structures contribute most to stability of the shoulder joint?

The muscle tendons that cross the shoulder contribute most to its stability

List the six features common to all synovial joints.

The six features of synovial joints are (1) articular cartilage, (2) a joint cavity, (3) an articular capsule, (4) synovial fluid, (5) reinforcing ligaments, (6) nerves and vessels.

Which forearm bone forms part of the elbow joint? Which forms part of the wrist joint?

The ulna forms part of the elbow. the radius forms part of the wrist joint.