JOINTS

Functions of joints

• Hold bones together• Allow for mobility

Ways joints are classified

• Functionally (how much they can move)• Structurally (what separates the two bones that are

articulated)

FUNCTIONAL CLASSIFICATION OF JOINTS

Synarthrosis

• Immovable

Amphiarthrosis

• Slightly movable

Diarthrosis

• Freely moveable

STRUCTURAL CLASSIFICATION OF JOINTS

Fibrous joints

• Generally immovable

Cartilaginous joints

• Immovable or slightly moveable

Synovial joints

• Freely moveable

SUMMARY OF JOINT CLASSES

[Insert Table 5.3 here]

Table 5.3

FIBROUS JOINTSBones united by fibrous tissue

Types:

1. SuturesHeld together by short

fibers- no movement• Example:

Coronal Suture

2. SyndesmosesHeld together by longer fibers-

slight movement• Example:

Distal end of tibia and fibula p169

CARTILAGINOUS JOINTSBones connected by cartilage

Example:

• Pubic symphysis• Intervertebral joints

SYNOVIAL JOINTSArticulating bones are separated by a joint cavity

Synovial fluid is found in the joint cavity

Ligaments reinforce the joint

STRUCTURES ASSOCIATED WITH THE SYNOVIAL JOINT

Bursae—flattened fibrous sacs

• Lined with synovial membranes• Filled with synovial fluid• Not actually part of the joint• Found where muscles, ligaments and/or tendons may rub on

bone

Tendon sheath

• Elongated bursa that wraps around a tendon

THE SYNOVIAL JOINT

Figure 5.29

TYPES OF SYNOVIAL JOINTS

Figure 5.30a–c

TYPES OF SYNOVIAL JOINTS

Figure 5.30d–f