Movement of the Joints

Range of Motion: the distance and direction a joint can move to its full potential Determines the positions the body can assume Plays an important role in athletic activity

Greatest Range of Motion is the Shoulder The greater the Range of Motion, the more the joint relies on attached muscles for stability Greatest Range of Motion is the Shoulder Hip is the next most Gymnast and Dancers train their hips to equal the ROM of the shoulder

Stability of the joint determined by 3 factors Shape of the bones at the joint Ligament that join the bones Muscle tone

Shape of Bones Ligaments If well matched, the joint is very stable Ex. The hip Ligaments The more ligaments that hold the joint, increases stability BUT joints that rely on the ligaments tend to be weak Ex. Ankle

Muscle Tone Most joints rely on this, this is the most stabilizing factor for the joint Ex. Shoulder and knee Muscle tone keeps the tendons that attach to the muscles tight/stretched (taut)

Types of Movement There are 18 different motions that joints can make

Flexion & Extension Flexion – decreases the angle between two bones Extension – increases the angle between two bones Hyperextenstion – increases the angle beyond the normal range of motion

Abduction & Adduction Abduction – Limbs only, move away from the midline Adduction – Limbs only, Toward midline

Rotation – bone turns on its axis to or form midline Ex. Head

Circumduction– limb moves in a circular path around an axis Proximal limb remains stationary Distal moves in a circle Combination of abduction, adduction, extension & Flexion Basically – one bone stays the other moves

Supination & Pronation Supination – turning the palm up Actually is the rotation of the ulna and radius Pronation – turning the palm down

Plantar & Dorsiflexion Plantarflexion – extend foot, toes point down Dorsiflexion – Flex foot, bring toes up

Inversion & Eversion Inversion – turn foot inward (medially) Eversion – turn foot out (laterally)

Protraction & Retraction Protraction – moving body forward on transverse plane Ex. Shoulder and mandible Retraction – moving body back on transverse plane

Elevation & Depression Elevation – move body up on frontal plane Ex. Shoulders Depression – move body down on frontal plane

Opposition – Move thumb to finger