u3-chp 9.4 movement at synv. joints

What are the four main types of motion at synovial joints?

Gliding, angular, rotational, and special movements.

What is gliding movement?

When two flat surfaces slide past each other (back-and-forth or side-to-side).

What joint does gliding occur in?

Plane joints (like between vertebrae).

Does the angle between bones change during gliding?

No, the angle stays the same.

What is angular movement?

Movement that changes the angle between two bones.

What are the 7 types of angular movements?

1. Flexion

2. Extension

3. Hyperextension

4. Lateral flexion

5. Abduction

6. Adduction

7. Circumduction

Define flexion.

Bending movement that decreases the angle between bones.

Example: Flexion of the elbow or knee.

Define extension.

Straightening movement that increases the angle between bones.

Example: Extending the elbow or knee.

Define hyperextension.

Extension of a joint beyond its normal anatomical position (past 180°).

Define abduction.

Movement away from the body’s midline.

Define adduction.

Movement toward the body’s midline.

What is lateral flexion?

Tilting the trunk to the side (in a coronal plane).

What is circumduction?

Movement in a circle or cone shape; combines flexion, abduction, extension, and adduction.

What is rotational movement?

When a bone pivots around its own longitudinal axis.

What are the 4 types of rotational movements?

1. Medial rotation (internal) – turns the front surface inward.

2. Lateral rotation (external) – turns the front surface outward.

3. Pronation – palm faces down/backward.

4. Supination – palm faces up/forward.

What are the 8 special movements?

1. Elevation – move body part upward.

2. Depression – move body part downward.

3. Protraction – move body part forward (jut out).

4. Retraction – move body part backward.

5. Inversion – sole of foot faces inward.

6. Eversion – sole of foot faces outward.

7. Plantar flexion – point toes downward.

8. Dorsiflexion – bring toes upward toward shin.

Which movements oppose each other?

• Flexion ↔ Extension

• Abduction ↔ Adduction

• Pronation ↔ Supination

• Elevation ↔ Depression

• Protraction ↔ Retraction

• Inversion ↔ Eversion

• Plantar flexion ↔ Dorsiflexion

(Circumduction has no direct opposite.)