Joints and Motion | HBS 2025-2026 | MDV

What role do joints play in the human body?

Joints are the places where two bones meet and allow for movement.

What is a Fibrous Joint?

A type of joint connected by dense connective tissue, allowing for minimal or no movement. Examples include sutures in the skull.

What is a Cartilaginous Joint?

A type of joint where bones are connected by cartilage, allowing for limited movement. Examples include the joints between the vertebrae and the pubic symphysis.

What is a Synovial Joint?

A type of joint in which the bones are separated by a fluid-filled joint cavity, allowing for a wide range of motion. Examples include the knee and elbow joints.

Where are Synovial Joints found?

Synovial joints are found at the hip, shoulders, elbows, knees, wrists, and ankles.

They are filled with synovial fluid and have synovial cavities.

What is Joint Articulation?

The way in which the parts come together at a joint.

What is a Hinge Joint?

A joint that opens and closes in one direction (flexion & extension).

Ex: Knee 

What is a Ball & Socket Joint?

A joint that rotates in any direction; contains a cup-like cavity with a balled head insertion.

Ex: Shoulder & Hips

What is a Condyloid Joint?

A joint that can rotate, albeit not in a full 360 degrees; Oval-shaped & fits into a cavity, similar to that of a ball and socket.

Ex: Wrist & Toe Joints

What is a Pivot Joint?

A joint that rotates in place w/out moving out of the original position.

Ex: Neck

What is a Plane/Planar Joint?

A joint where one piece slides over the other without rotation.

Ex: Carpal bones join the wrist to the forearm OR some bones in the foot.

What is a Saddle Joint?

A joint that moves in any direction, but cannot twist or rotate; it looks like a horse saddle.

Ex: Joint where the thumb meets the hand.

Medial Collateral Ligament (MCL)

Connects the femur to the tibia & provides stability to the inner knee; wide and flat.

Tip: can locate by finding the fibula, then going opposite.

Lateral Collateral Ligament (LCL)

Connects the femur to the fibula; thinner and rounder than MCL.

Tip: Look for the fibula.

Anterior Cruciate Ligament (ACL)

Connects femur to the tibia; towards the front.

Tip: Determine anterior or posterior views.

Posterior Cruciate Ligament (PCL)

Connects the femur to the tibia; towards the back, stronger than the ACL.

Tip: Determine anterior or posterior views.

Anterior Drawer Test

Checks ACL stability by pulling the tibia forward.

Posterior Drawer Test

Checks PCL stability by pushing the tibia backward.

Valgus Stress Test

Checks MCL stability by applying inward pressure.

Varus Stress Test

Checks LCL stability by applying outward pressure.

Valgus

Inward

Varus

Outward

Goniometer

An instrument used to measure the angles of a joint.

Range of Motion (ROM)

Studies that assess joint and provides a measure of overall flexibility.

Hyaline Cartilage

The most common type of cartilage found in joints.

Ex: nose, ribs, trachea

Elastic Cartilage

Cartilage is found in the ear, epiglottis, and larynx.

Fibrocartilage

Cartilagle found in the intervertebral discs, pubic symphysis, and knee meniscus.

Adduction

Moving a limb toward the midline of the body.

Abduction

Moving a limb away from the midline of the body.

Rotation

When a joint moves in a circular motion around its own axis.

Circumduction

When a joint moves in a circular motion (complete movement) such as from a ball and socket joint.

Elevation

Movement in a superior direction.

Depression

Movement in an inferior direction.

Flexion

Movement that decreases the angles between two body parts.

Extension

Movement that increases the angles between two body parts.

Hyperextension

Movement of a joint beyond its normal ROM, resulting in an excessive straightening or opening angle.

Plantar Flexion

Extension at the ankle where the foot points downward (toes down).

Dorsiflexion

Flexion at the ankle so that the foot points upward.