MUSCULOSKELETAL SYSTEM (JOINT/ ARTICULATION)

By.

Alit Adi Sanjaya

Joint/articulation is a conncetion between two bones or more. Joints cause elbows and knees can fold and rotate. There are three types of joints: diatrhrosis, amphiarthrosis, and synarthrosis.

a.    Diarthrosis

Diarthrosis is a joint that it is possible to move freely. The synonym of diarthrosis is synovial joints. This joint cause many kinds of movement. In this joint bone meet in articular/joint capsule. There is synovial membrane in articular/joint capsule that expect synovial liquid (joint lubricant) that fills joint socket. The function of synovial liquid are to grease joint, feed the cells in joints area, and absorb shock. Synovial liuquid is by sinovial membrane cells. In joints, theree are cartilaginous tisssues taht coat the joint. All diarthrosis joint have synovial socket. Diarthrosis joints consist of hinge joint, gliding joint, pivot joint, saddle joint, ball-and-socket joint, and condyloid joint.

1.    Hinge joint

Hinge joint ios in elbow and knee. In this joint, the end of a bone that is curve joins with another end of a bone that is concave. This joint produce one axial movement looks like in doo-hingeor window-hinge.

2.    Gliding joint

Gliding joint is a connection of flat interskeleton, for example the joint between carpal and metacarpal. This joint produces awkward slidding movement and doesn’t have axis, example forward and backward movement.

3.    Pivot joint

In pivot joint, one bone end twined around (forming rings) the other end. Pivot joint is in joining of atlas bone and axis bone that cause our head can be rotate and shake from side to side.

4.    Saddle joint

In this joint, other bone end looks like saddle and another end is inside of it. For example, metacarpal is a saddle for phalanx. The movement produce are axial and limited.

5.    Ball-and-socket joint

Ball-and-socket  has the characteristic that one bone is hump and it gets in another bone end looks like a bowl. This joint produce free three axial movement. Ball-and-socket joint connect humerus with scapula, and femur with pelvis.

6.    Condyloid joint

The characteristic of condyloid joint is one epiphysis is oval and come inside of another lobed epiphysis. This joint produce two axial movements, example left to right movement, forward to backward, back and front movement. The condyloid movement is in joint between carpal with radius and ulna.

b.    Amphiarthrosis

Amphiarthrosis is a connection of interskeleton that is connected by cartilage so it may create few movement. Types of amphiathrosis joint which is simphysis and syndesmosis.

1.    Simphysis

Its called symphysis if the joint is connected by cartilage. For example vertebrae joint and symphysis pubis

2.    Syndesmosis

Its called syndesmosis if a connection of interjoint that is connected by cartilage and ligamnents. For example the joint between fibula and tibia.

c.    Synarthrosis

Synarthrosis is a joining of interbones that is connected by ligaments that suffers from ossification so it may not create a movement.  The types of this joint that is synchondrosis and synfibrosis.

1.    Synchondrosis

In synchondrosis, the two bone ends are connected by hyaline, for example the joining between ribs bone and vertebrae.

2.    Synfibrosis

In synfibrosis, the two bone end are connected by dense fibrous connective tissue, for example suture.