YMCA L2 Anatomy - Joint Actions

Elevation refers to the action of lifting or raising a joint. This movement is typically performed in the vertical direction, such as when raising the shoulders or lifting the chin. It is the opposite of depression, which involves lowering or moving a joint downward. Protraction refers to moving a joint forward, while supination refers to rotating the forearm or foot outward. Therefore, elevation is the correct answer in this case.

Pronation and supination are movements that involve rotation of the forearm and hand. Pronation refers to the rotation of the forearm and hand so that the palm faces downwards, while supination refers to the rotation that brings the palm to face upwards. These movements occur at the joint between the radius and ulna bones in the forearm, allowing for a wide range of motion and enabling activities such as turning a doorknob or pouring a drink. Therefore, the correct answer is forearm and hand.

Flexion and extension are the joint actions that take place at the knee. Flexion refers to the bending of the knee, bringing the lower leg closer to the thigh, while extension refers to the straightening of the knee, returning the lower leg to its original position. These movements are essential for activities such as walking, running, and jumping, as they allow for the proper functioning and mobility of the knee joint.

Depression refers to the dropping or downward movement of the shoulders. It is a common physical manifestation of sadness or low mood, where the individual's posture reflects a lack of energy and a sense of defeat. This can be seen as a slumping or hunching of the shoulders, giving the appearance of a downward or depressed position. In contrast, pronation refers to the inward rotation of the forearm, retraction refers to the backward movement of a body part, and rotation refers to the circular movement around an axis.

Plantarflexion and dorsiflexion are joint actions that occur at the ankle. Plantarflexion refers to the movement of pointing the foot downwards, like standing on tiptoes, while dorsiflexion refers to the movement of pulling the foot upwards, like lifting the toes towards the shin. These actions involve the muscles and tendons in the ankle joint, allowing for movement and stability in the foot.

Circumduction is a circular movement of the body that involves the sequential combination of flexion, abduction, extension, and adduction of a joint. This movement allows the body part to move in a circular path, such as when rotating the arm in a windmill motion. Rotation, on the other hand, refers to the movement of a body part around its own axis. Dorsi-flexion involves flexing the foot towards the shin, while retraction refers to the backward movement of a body part.

Circumduction is a movement that involves the circular movement of a body part, such as rotating the arm in a circular motion. This type of movement is possible at the shoulder joint, where the rounded head of the humerus fits into the shallow socket of the scapula, allowing for a wide range of motion. The knee, elbow, and ankle joints do not allow for circumduction as they are hinge joints that primarily allow for flexion and extension movements.

When the palms turn down, it indicates pronation. Pronation is the joint action where the palm of the hand rotates inwards or downwards. This movement occurs at the forearm, specifically at the radius and ulna bones. Pronation allows the hand to face downwards or towards the back of the body.

Plantarflexion is the joint action that points the toes away from the body. This movement occurs when the foot is flexed downward, such as when standing on tiptoes. It involves the contraction of the muscles in the back of the lower leg, specifically the calf muscles, which pull the heel upward and the toes downward. This action is important for activities such as walking, running, and jumping.

A standing side bend involves bending the spine laterally, which means bending the spine to the side. This movement is known as lateral flexion. Lateral extension refers to straightening the spine from a laterally flexed position, which is not the action involved in a standing side bend. Horizontal flexion and extension refer to movements that occur in the horizontal plane, which is not relevant to a standing side bend. Therefore, the correct joint action for a standing side bend is lateral flexion.

At a pivot joint, the movement that is possible is rotation. Pivot joints are characterized by the rotation of one bone around another bone, similar to the movement of a wheel on an axle. This type of joint allows for rotational movements in various directions, such as the rotation of the head from side to side or the rotation of the forearm to turn the palm up or down. Flexion, circumduction, and adduction are movements that occur at other types of joints, but not at pivot joints.

Adduction is the correct answer because it refers to the movement of a body part towards the midline of the body. This movement brings the body part closer to the center of the body, such as when bringing the arms or legs closer to the torso. Abduction, on the other hand, is the movement away from the midline, while protraction refers to moving a body part forward, and pronation refers to the rotation of the forearm so that the palm faces downwards.

When the quadriceps contract concentrically, it means that they are shortening and pulling on the patellar tendon, causing the leg to straighten. This movement is known as extension.

The lumbar region of the spine is where the available rotation is greatest. This is because the lumbar spine is located in the lower back and is designed to provide flexibility and support for activities such as bending, twisting, and lifting. The lumbar vertebrae are larger and more mobile compared to the thoracic and sacral vertebrae, allowing for a greater range of motion and rotation in this region. The thoracic spine is more rigid due to the presence of the rib cage, while the sacral and coccyx regions have limited movement.

Flexion is the correct answer because it is a movement that occurs at the wrist joint. Flexion refers to the movement of bending the wrist towards the palm, decreasing the angle between the hand and forearm. This action is possible due to the presence of several muscles and tendons in the wrist joint that allow for flexion and extension movements.

Lateral flexion/extension is the joint action that takes place in the shoulders. This movement involves bending the torso sideways, away from the midline of the body, and then returning it back to an upright position. The shoulders play a significant role in this movement as they allow for the necessary range of motion and stability required for lateral flexion/extension.