Body Movements Flashcards
What is a movement?
Movement involves an entity moving from point A to point B. The movement is carried out around a fixed axis or fulcrum and has a direction.
Anatomical movements are no different. They usually involve bones or body parts moving around fixed joints relative to the main anatomical planes parallel to them.
What do anatomical movements consist of?
- Anatomical structures involved in the movement.
- Reference axes around which the movement
happens. - Direction, which in anatomy is usually related to a
standard plane.
Not all of them are required for every movement.
What are the types of movement?
- Protraction / Retraction
- Flexion / Extension
- Elevation / Depression
- Adduction / Abduction
- Medial Rotation / Lateral Rotation
- Pronation / Supination
- Inversion / Eversion
- Opposition / Reposition
- Deviation
- Circumduction
Protraction / Retraction
The movements of protrusion and retrusion take place in the sagittal plane. Since they are also related to the frontal/coronal axis, but instead of only moving around it, these movements are also taking place parallel to it. Protrusion involves a movement going straight ahead or forward.
Retrusion is the opposite and involves going backwards. Anatomical structures capable of such actions are the tongue, chin (mandible) and lips.
Flexion / Extension
The opposing movements of flexion and extension take place in sagittal directions around a frontal/coronal axis.
Flexion, or bending, involves decreasing the angle between the two entities taking part in the movement (bones or body parts). In contrast, extension, or straightening, involves increasing the respective angle.
Elevation / Depression
While protrusion and retrusion move anatomical structures forward and backwards, depression and elevation move them down (inferiorly) and up (superiorly), respectively.
Adduction / Abduction
The movements of abduction and adduction are intimately related to the median plane. They both generally occur in the frontal plane and are happening around an anteroposterior axis.
Medial Rotation / Lateral Rotation
Rotation happens in the transverse plane around a vertical (longitudinal) axis that happens relative to the median plane.
Medial rotation involves bringing the anatomical structure closer to the median plane, while lateral rotation involves moving it further away.
Pronation / Supination
Pronation and supination are considered as two special types of rotation. They are restricted to the forearm and involve the radius twisting over the ulna.
Inversion / Eversion
Inversion and eversion take place relative to the median place and are specific to the foot.
In eversion, the plantar side of the foot is moved away from the median plane so that it is turned laterally. In inversion, the plantar side is moved towards the median plane, resulting in a medial turn.
Opposition / Reposition
These two movements are restricted to the digits of the hand. Essentially, they involve pinching, such as when sprinkling salt over food or snapping your fingers. Anatomically speaking, opposition involves touching the pad of any one of your fingers with the thumb of the same hand. Reposition is the reverse, which consists of separating them.
Deviation
Deviation is a special type of movement that is restricted to the wrist joint. The movement happens in a longitudinal plane through the wrist relative to an axis passing from palmar to dorsal through the wrist.
Circumduction
Circumduction is a special type of movement that is actually a combination of many other ones. The overall movement starts with flexion, followed by abduction, extension and finally adduction. The order must be sequential, but it can start from either flexion or adduction. The result is a circular movement. Due to the multitude of movements, circumduction is restricted to ball-and-socket type joints, such as the shoulder and the hip.
Hyperflexion and Hyperextension
Hyperflexion and hyperextension are exaggerated movements beyond the normal limit permitted by a joint. It can happen in limbs or the vertebral column and can result in ligament tear, damage, or dislocations.
Hyperextension of the vertebral column, which can happen during sudden acceleration and deceleration, is particularly dangerous. The overextension of the cervical part of the column can result in a whiplash injury and can be a potential threat to the integrity of the spinal cord.
