Define the different species of body movementsIdentify the joints that allow for this motions

Synovial joints permit the human body a tremendous selection of movements. Each motion at a synovial joint outcomes from the convulsion or relaxation of the muscles that room attached to the skeleton on either side of the articulation. The form of activity that deserve to be developed at a synovial joint is figured out by its structural type. When the ball-and-socket joint gives the greatest selection of movement at an individual joint, in various other regions that the body, numerous joints might work together to create a details movement. Overall, each type of synovial joint is essential to carry out the body v its an excellent flexibility and also mobility. There are many varieties of activity that can take place at synovial joints ((Figure)). Movement varieties are usually paired, v one gift the the contrary of the other. Body activities are always described in relationship to the anatomical place of the body: upright stance, through upper limbs to the side of body and also palms dealing with forward. Describe (Figure) as you go through this section.

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Watch this video clip to learn around anatomical motions. What motions involve increasing or to decrease the edge of the foot in ~ the ankle?


Synovial joints provide the body plenty of ways in which to move. (a)–(b) Flexion and extension motions are in the sagittal (anterior–posterior) airplane of motion. These activities take place at the shoulder, hip, elbow, knee, wrist, metacarpophalangeal, metatarsophalangeal, and interphalangeal joints. (c)–(d) Anterior bending the the head or vertebral column is flexion, while any kind of posterior-going activity is extension. (e) Abduction and adduction are movements of the limbs, hand, fingers, or toe in the coronal (medial–lateral) plane of movement. Moving the limb or hand laterally far from the body, or spreading the fingers or toes, is abduction. Adduction brings the limb or hand towards or across the midline of the body, or bring the finger or toe together. Circumduction is the movement of the limb, hand, or finger in a one pattern, utilizing the sequential combination of flexion, adduction, extension, and abduction motions. Adduction/abduction and also circumduction take location at the shoulder, hip, wrist, metacarpophalangeal, and metatarsophalangeal joints. (f) turning of the head side to next or twisting the the body is rotation. Medial and lateral rotation of the upper limb in ~ the shoulder or reduced limb at the i know well involves transforming the anterior surface of the limb toward the midline that the body (medial or inner rotation) or far from the midline (lateral or outside rotation).

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(g) Supination that the forearm transforms the hand to the palm forward place in i m sorry the radius and also ulna room parallel, if forearm pronation turns the hand come the palm backward place in which the radius the cross over the ulna to form an “X.” (h) Dorsiflexion that the foot at the ankle joint moves the top of the foot toward the leg, if plantar flexion elevator the heel and also points the toes. (i) Eversion the the foot moves the bottom (sole) the the foot far from the midline the the body, while foot inversion faces the single toward the midline. (j) Protraction the the mandible pushes the chin forward, and also retraction traction the chin back. (k) Depression the the mandible opens up the mouth, while elevation closes it. (l) the contrary of the thumb brings the pointer of the thumb into call with the reminder of the fingers of the exact same hand and also reposition brings the thumb earlier next come the index finger.
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Flexion and Extension

Flexion and also extension are motions that take location within the sagittal plane and involve anterior or posterior movements of the body or limbs. Because that the vertebral column, flexion (anterior flexion) is an anterior (forward) bending of the neck or body, if extension entails a posterior-directed motion, such together straightening native a flexed position or bending backward. Lateral flexion is the bending of the neck or body toward the right or left side. These activities of the vertebral shaft involve both the symphysis joint created by every intervertebral disc, as well as the plane form of synovial share formed in between the worse articular procedures of one vertebra and the exceptional articular processes of the next reduced vertebra.

In the limbs, flexion decreases the angle in between the skeleton (bending the the joint), while extension increases the angle and also straightens the joint. Because that the top limb, every anterior-going movements are flexion and all posterior-going activities are extension. These include anterior-posterior motions of the eight at the shoulder, the forearm at the elbow, the hand at the wrist, and the finger at the metacarpophalangeal and also interphalangeal joints. For the thumb, expansion moves the thumb away from the palm of the hand, in ~ the same plane as the palm, if flexion brings the ignorance back versus the index finger or right into the palm. These movements take place at the first carpometacarpal joint. In the reduced limb, happen the thigh forward and also upward is flexion at the i know well joint, while any type of posterior-going motion of the thigh is extension. Note that expansion of the thigh past the anatomical (standing) position is greatly limited by the ligaments that support the i know well joint. Knee flexion is the bending that the knee to lug the foot toward the posterior thigh, and also extension is the straightening that the knee. Flexion and also extension movements are watched at the hinge, condyloid, saddle, and ball-and-socket joints that the four (see (Figure)a-d).

Hyperextension is the abnormal or extreme extension of a joint past its normal variety of motion, hence resulting in injury. Similarly, hyperflexion is excessive flexion in ~ a joint. Hyperextension injuries are usual at hinge joints such as the knee or elbow. In situations of “whiplash” in i beg your pardon the head is suddenly moved backward and also then forward, a patient may experience both hyperextension and hyperflexion of the cervical region.


Abduction and also Adduction

Abduction and also adduction motions happen within the coronal aircraft and involve medial-lateral movements of the limbs, fingers, toes, or thumb. Abduction moves the body laterally far from the midline that the body, while adduction is the opposing movement that bring the limb towards the body or across the midline. Because that example, kidnapping is elevating the arm at the shoulder joint, moving it laterally far from the body, if adduction brings the arm down to the next of the body. Similarly, abduction and also adduction in ~ the wrist move the hand away from or toward the midline the the body. Dispersing the finger or toes personally is likewise abduction, while bringing the fingers or toes with each other is adduction. Because that the thumb, kidnapping is the anterior motion that brings the thumb to a 90° perpendicular position, pointing right out indigenous the palm. Adduction moves the thumb earlier to the anatomical position, beside the index finger. Abduction and adduction activities are watched at condyloid, saddle, and ball-and-socket joints (see (Figure)e).


Circumduction

Circumduction is the activity of a body region in a circular manner, in i m sorry one finish of the body region being moved stays relatively stationary when the other end defines a circle. It involves the sequential combination of flexion, adduction, extension, and also abduction at a joint. This type of movement is discovered at biaxial condyloid and saddle joints, and also at multiaxial ball-and-sockets joints (see (Figure)e).


Rotation

Rotation can happen within the vertebral column, in ~ a pivot joint, or at a ball-and-socket joint. Rotation of the neck or human body is the twisting movement created by the summation the the little rotational movements easily accessible between nearby vertebrae. At a pivot joint, one bone rotates in relation to an additional bone. This is a uniaxial joint, and also thus rotation is the just motion enabled at a pivot joint. Because that example, at the atlantoaxial joint, the an initial cervical (C1) vertebra (atlas) rotates about the dens, the upward estimate from the 2nd cervical (C2) vertebra (axis). This permits the head to turn from next to side as when shaking the head “no.” The proximal radioulnar joint is a pivot joint developed by the head that the radius and also its articulation v the ulna. This joint permits for the radius to revolve along the length during pronation and also supination movements of the forearm.

Rotation can likewise occur at the ball-and-socket joints of the shoulder and hip. Here, the humerus and femur rotate about their long axis, which moves the anterior surface ar of the arm or thigh either toward or far from the midline the the body. Motion that bring the anterior surface of the limb toward the midline of the human body is referred to as medial (internal) rotation. Conversely, rotation the the body so the the anterior surface ar moves away from the midline is lateral (external) rotation (see (Figure)f). Be sure to distinguish medial and lateral rotation, which have the right to only happen at the multiaxial shoulder and hip joints, from circumduction, i beg your pardon can take place at one of two people biaxial or multiaxial joints.


Supination and also Pronation

Supination and pronation are movements of the forearm. In the anatomical position, the top limb is organized next come the body with the palm dealing with forward. This is the supinated place of the forearm. In this position, the radius and also ulna space parallel to every other. Once the palm that the hand faces backward, the forearm is in the pronated position, and also the radius and also ulna form an X-shape.

Supination and also pronation room the movements of the forearm the go in between these 2 positions. Pronation is the motion that move the forearm native the supinated (anatomical) place to the pronated (palm backward) position. This movement is developed by rotation that the radius in ~ the proximal radioulnar joint, attach by movement of the radius in ~ the distal radioulnar joint. The proximal radioulnar joint is a pivot joint that permits for rotation that the head of the radius. Since of the slight curvature of the shaft of the radius, this rotation reasons the distal finish of the radius to cross over the distal ulna at the distal radioulnar joint. This crossing over brings the radius and also ulna into an X-shape position. Supination is opposing motion, in which rotation of the radius returns the skeleton to your parallel positions and moves the palm come the anterior encountering (supinated) position. It helps to remember the supination is the movement you use as soon as scooping increase soup with a spoon (see (Figure)g).


Dorsiflexion and Plantar Flexion

Dorsiflexion and also plantar flexion are activities at the fish eye joint, i m sorry is a hinge joint. Lifting the front of the foot, so that the peak of the foot moves toward the anterior foot is dorsiflexion, if lifting the heel of the foot indigenous the soil or pointing the toes bottom is plantar flexion. These room the only movements obtainable at the ankle joint (see (Figure)h).


Inversion and Eversion

Inversion and also eversion are complex movements that involve the multiple plane joints among the tarsal skeletal of the posterior foot (intertarsal joints) and thus space not motions that take location at the ankle joint. Turning back is the turning of the foot to angle the bottom of the foot toward the midline, when eversion transforms the bottom of the foot far from the midline. The foot has a greater selection of inversion 보다 eversion motion. This are necessary motions that aid to stabilize the foot once walking or to run on one uneven surface and aid in the fast side-to-side transforms in direction provided during active sports such as basketball, racquetball, or soccer (see (Figure)i).


Protraction and Retraction

Protraction and retraction space anterior-posterior movements of the scapula or mandible. Protraction that the scapula occurs once the shoulder is moved forward, as as soon as pushing versus something or throw a ball. Retraction is the opposite motion, through the scapula being pulled posteriorly and also medially, toward the vertebral column. Because that the mandible, protraction occurs as soon as the lower jaw is driven forward, come stick out the chin, if retraction pulls the lower jaw backward. (See (Figure)j.)


Depression and Elevation

Depression and also elevation space downward and also upward movements of the scapula or mandible. The upward movement of the scapula and also shoulder is elevation, when a downward activity is depression. These movements are supplied to shrug your shoulders. Similarly, elevation of the mandible is the upward movement of the lower jaw offered to nearby the mouth or bite top top something, and depression is the downward motion that produces opening of the mouth (see (Figure)k).


Excursion

Excursion is the next to side movement of the mandible. Lateral excursion moves the mandible far from the midline, toward either the right or left side. Medial excursion returns the mandible to its resting place at the midline.


Superior Rotation and also Inferior Rotation

Superior and also inferior rotation are motions of the scapula and are defined by the direction of movement of the glenoid cavity. These motions involve rotation of the scapula roughly a point inferior come the scapular spine and also are created by combine of muscles acting on the scapula. During superior rotation, the glenoid cavity move upward as the medial finish of the scapular spine move downward. This is a very important movement that contributes to upper limb abduction. Without exceptional rotation of the scapula, the higher tubercle of the humerus would hit the acromion that the scapula, thus preventing any abduction that the arm above shoulder height. Premium rotation of the scapula is thus forced for complete abduction of the upper limb. Exceptional rotation is likewise used without arm abduction when carrying a hefty load v your hand or on her shoulder. You deserve to feel this rotation once you pick up a load, such together a heavy book bag and carry that on just one shoulder. To boost its weight-bearing support for the bag, the shoulder lifts together the scapula superiorly rotates. Worse rotation occurs during limb adduction and also involves the downward activity of the glenoid cavity through upward activity of the medial end of the scapular spine.


Opposition and also Reposition

Opposition is the thumb motion that bring the tip of the thumb in contact with the guideline of a finger. This motion is created at the an initial carpometacarpal joint, which is a saddle share formed between the trapezium carpal bone and also the first metacarpal bone. Thumb opposition is developed by a mix of flexion and abduction that the ignorance at this joint. Return the ignorance to the anatomical position next to the index finger is referred to as reposition (see (Figure)l).

Movements the the JointsType that JointMovementExample
PivotUniaxial joint; allows rotational movementAtlantoaxial share (C1–C2 vertebrae articulation); proximal radioulnar joint
HingeUniaxial joint; allows flexion/extension movementsKnee; elbow; ankle; interphalangeal joints the fingers and also toes
CondyloidBiaxial joint; allows flexion/extension, abduction/adduction, and circumduction movementsMetacarpophalangeal (knuckle) joints that fingers; radiocarpal joint of wrist; metatarsophalangeal joints for toes
SaddleBiaxial joint; enables flexion/extension, abduction/adduction, and circumduction movementsFirst carpometacarpal share of the thumb; sternoclavicular joint
PlaneMultiaxial joint; permits inversion and also eversion that foot, or flexion, extension, and lateral flexion that the vertebral columnIntertarsal joints of foot; superior-inferior articular process articulations in between vertebrae
Ball-and-socketMultiaxial joint; enables flexion/extension, abduction/adduction, circumduction, and also medial/lateral rotation movementsShoulder and hip joints

Chapter Review

The variety of movements listed by the different varieties of synovial joints allows for a big range of body motions and gives you remarkable mobility. These movements enable you come flex or prolong your body or limbs, medially rotate and adduct her arms and also flex your elbows to host a hefty object against your chest, raise her arms above your head, rotate or shake her head, and also bend come touch the toes (with or without bending her knees).

Each of the various structural species of synovial joints also permit for details motions. The atlantoaxial pivot joint provides side-to-side rotation that the head, if the proximal radioulnar articulation allows for rotation that the radius during pronation and also supination of the forearm. Hinge joints, such as at the knee and also elbow, allow only for flexion and also extension. Similarly, the hinge joint of the ankle only allows for dorsiflexion and plantar flexion of the foot.

Condyloid and saddle joints are biaxial. These permit for flexion and also extension, and also abduction and adduction. The sequential combination of flexion, adduction, extension, and also abduction produces circumduction. Multiaxial plane joints carry out for only tiny motions, however these can include together over several nearby joints to create body movement, such as inversion and also eversion the the foot. Similarly, airplane joints enable for flexion, extension, and also lateral flexion movements of the vertebral column. The multiaxial ball and also socket joints permit for flexion-extension, abduction-adduction, and circumduction. In addition, these also permit for medial (internal) and lateral (external) rotation. Ball-and-socket joints have actually the greatest range of movement of every synovial joints.


Watch this video to learn around anatomical motions. What activities involve boosting or to decrease the edge of the foot in ~ the ankle?


Dorsiflexion of the foot in ~ the ankle to reduce the edge of the fishing eye joint, if plantar flexion boosts the angle of the fish eye joint.


The joints between the articular processes of adjacent vertebrae can contribute to i m sorry movement?

lateral flexioncircumductiondorsiflexionabduction

Which activity moves the bottom the the foot far from the midline of the body?

elevationdorsiflexioneversionplantar flexion

Movement the a body an ar in a circular movement at a condyloid joint is what type of motion?

rotationelevationabductioncircumduction

Supination is the activity that move the ________.

hand indigenous the palm backward place to the palm front positionfoot so the the bottom the the foot encounters the midline that the bodyhand indigenous the palm forward place to the palm behind positionscapula in an increase direction

Movement in ~ the shoulder joint the moves the top limb laterally away from the human body is dubbed ________.

elevationeversionabductionlateral rotation

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Critical reasoning Questions


Briefly define the types of share movements obtainable at a ball-and-socket joint.


Ball-and-socket joints space multiaxial joints that enable for flexion and also extension, abduction and also adduction, circumduction, and also medial and also lateral rotation.


Discuss the joints involved and movements forced for you to cross your arms with each other in front of your chest.

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To cross your arms, you have to use both your shoulder and also elbow joints. In ~ the shoulder, the eight would have to flex and medially rotate. At the elbow, the forearm would must be flexed.


Glossary

abductionmovement in the coronal plane that move a body laterally away from the body; spreading of the fingersadductionmovement in the coronal aircraft that moves a limb medially towards or throughout the midline of the body; bringing fingers togethercircumductioncircular activity of the arm, thigh, hand, thumb, or finger that is developed by the sequential mix of flexion, abduction, extension, and also adductiondepressiondownward (inferior) activity of the scapula or mandibledorsiflexionmovement at the ankle that brings the top of the foot toward the anterior legelevationupward (superior) motion of the scapula or mandibleeversionfoot movement including the intertarsal joints of the foot in i beg your pardon the bottom the the foot is turned laterally, far from the midlineextensionmovement in the sagittal aircraft that increases the angle of a share (straightens the joint); motion including posterior bending the the vertebral pillar or return to the upright place from a flexed positionflexionmovement in the sagittal airplane that to reduce the edge of a share (bends the joint); motion involving anterior bending the the vertebral columnhyperextensionexcessive extension of joint, past the normal variety of movementhyperflexionexcessive flexion the joint, beyond the normal selection of movementinferior rotationmovement of the scapula during upper limb adduction in which the glenoid cavity of the scapula moves in a downward direction together the medial end of the scapular spine move in an upward directioninversionfoot movement including the intertarsal joints that the foot in i beg your pardon the bottom that the foot is turned toward the midlinelateral excursionside-to-side motion of the mandible away from the midline, towards either the right or left sidelateral flexionbending that the neck or body towards the best or left sidelateral (external) rotationmovement that the arm at the shoulder joint or the thigh in ~ the hip joint the moves the anterior surface ar of the limb away from the midline the the bodymedial excursionside-to-side activity that returns the mandible come the midlinemedial (internal) rotationmovement the the arm at the shoulder joint or the thigh in ~ the i know well joint that brings the anterior surface ar of the limb towards the midline of the bodyoppositionthumb movement that bring the reminder of the ignorance in contact with the reminder of a fingerplantar flexionfoot movement at the fish eye in which the hoe is lifted turn off of the groundpronated positionforearm position in i m sorry the palm faces backwardpronationforearm motion that moves the palm the the hand from the palm front to the palm behind positionprotractionanterior movement of the scapula or mandiblerepositionmovement the the ignorance from opposition earlier to the anatomical place (next to index finger)retractionposterior activity of the scapula or mandiblerotationmovement the a bone around a central axis (atlantoaxial joint) or approximately its long axis (proximal radioulnar joint; shoulder or hip joint); twisting the the vertebral shaft resulting native the summation of small motions between surrounding vertebraesuperior rotationmovement that the scapula during upper limb abduction in which the glenoid cavity of the scapula move in an upward direction as the medial end of the scapular spine move in a downward directionsupinated positionforearm place in which the palm encounters anteriorly (anatomical position)supinationforearm activity that move the palm of the hand indigenous the palm backward to the palm front position