Condyloid - contains a convex surface which articulates with a concave elliptical cavity.It is formed by a central bony pivot, which is surrounded by a bony-ligamentous ring
Plane - the articular surfaces are relatively flat, allowing the bones to glide over one another.It is characterised by opposing articular surfaces with a reciprocal concave-convex shape. Saddle - named due to its resemblance to a saddle on a horse's back.Hinge - permits movement in one plane - usually flexion and extension.Fig 2 - Adjacent vertebral bodies are connected by fibrocartilage: an example of a symphysis They are slightly movable (amphiarthrosis).Įxamples include the pubic symphysis, and the joints between vertebral bodies. Symphysial joints are where the bones are united by a layer of fibrocartilage. These joints are immovable (synarthrosis).Īn example of a synchondrosis is the joint between the diaphysis and epiphysis of a growing long bone.
In a synchondrosis, the bones are connected by hyaline cartilage. There are two main types: synchondroses (primary cartilaginous) and symphyses (secondary cartilaginous). In a cartilaginous joint, the bones are united by fibrocartilage or hyaline cartilage. The middle radioulnar joint and middle tibiofibular joint are examples of a syndesmosis joint. They are comprised of bones held together by an interosseous membrane. Syndesmoses are slightly movable joints (amphiarthroses). The tooth is bound into its socket by the strong periodontal ligament. They are found where the teeth articulate with their sockets in the maxilla (upper teeth) or the mandible (lower teeth). Fig 1 - Bones of the calvarium and cranial base. They are most important in birth, as at that stage the joints are not fused, allowing deformation of the skull as it passes through the birth canal.
There is limited movement until about 20 years of age, after which they become fixed and immobile. Sutures are immovable joints (synarthrosis), and are only found between the flat, plate-like bones of the skull. These are typically joints that require strength and stability over range of movement.įibrous joints can be further sub-classified into sutures, gomphoses and syndesmoses.
AREA WHERE TWO OR MORE BONES JOIN TOGETHER FREE
It permits free movement in numerous axes.Ī joint is defined as a connection between two bones in the skeletal system. Ball and Socket – where the ball-shaped surface of one rounded bone fits into the cup-like depression of another bone.wrist joint, metacarpophalangeal joint, metatarsophalangeal joint. Condyloid – contains a convex surface which articulates with a concave elliptical cavity.proximal and distal radioulnar joints, atlantoaxial joint. Plane – the articular surfaces are relatively flat, allowing the bones to glide over one another.Saddle – named due to its resemblance to a saddle on a horse’s back.Hinge – permits movement in one plane – usually flexion and extension.Synovial joints can be sub-classified into several different types, depending on the shape of their articular surfaces and the movements permitted: They are freely movable (diarthrosis) and are the most common type of joint found in the body. A synovial joint is defined by the presence of a fluid-filled joint cavity contained within a fibrous capsule.
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