The joints are the regions that join two bones together. Examples of joints include: knee, ankle, hip, shoulder, elbow, wrist, knuckles, and many others. Joint symptoms include joint pain, joint redness, joint swelling, joint weakness, and many other symptoms. Symptoms of specific joints include knee symptoms, ankle symptoms, hip symptoms, elbow symptoms, wrist symptoms, shoulder symptoms, knuckle symptoms, and many others. Joint disorders include joint injuries, arthritis (osteoarthritis), rheumatoid arthritis, joint infections, joint inflammations. Disorders of particular joints include knee disorders, ankle disorders, hip disorders, elbow disorders, wrist disorders, shoulder disorders, knuckle disorders, and many others.

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Joint capsule. A tough membrane that encloses all the bones and other joint parts.

Source: MedLinePlus Magazine (NIH)1

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Joint Basics

The point at which two or more bones are connected is called a joint. In all joints, the bones are kept from grinding against each other by a lining called cartilage. Bones are joined to bones by strong, elastic bands of tissue called ligaments. Muscles are connected to bones by tough cords of tissue called tendons. Muscles pull on tendons to move joints. Although muscles are not technically part of a joint, they’re important because strong muscles help support and protect joints.

Source: NIAMS (NIH)2

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Joint Capsule: The sac enclosing a joint. It is composed of an outer fibrous articular capsule and an inner Synovial Membrane.3

Anatomical Information about Joints

In a healthy joint, the ends of bones are encased in smooth cartilage. Together, they are protected by a joint capsule lined with a synovial membrane that produces synovial fluid. The capsule and fluid protect the cartilage, muscles, and connective tissues.

Source: MedLinePlus Magazine (NIH)4

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Osteoarthritis Basics: The Joint and Its Parts

Joints allow movement between the bones and absorb the shock from walking or other repetitive motion. Joints are made up of:

Cartilage. A hard, slippery coating on the end of each bone.

Joint capsule. A tough membrane that encloses all the bones and other joint parts.

Synovium (sin-O-vee-um). A thin membrane inside the joint capsule that secretes synovial fluid.

Synovial fluid. A fluid that lubricates the joint and keeps the cartilage smooth and healthy.

Ligaments, tendons, and muscles. Tissues that surround the bones and joints, a llowing the joints to bend and move. Ligaments are tough, cord-like tissues that connect one bone to another. Tendons are tough fibers that connect muscles to bones. Muscles are bundles of specialized cells that, when stimulated by nerves, either relax or contract to produce movement.

Source: MedLinePlus Magazine (NIH)5


Types may include:6

Types of Joint:

  • Amphiarthrosis
  • Diarthrosis
  • Joint By Site
  • Synarthrosis

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  1. Source: MedLinePlus Magazine (NIH): magazine/ issues/ winter13/ articles/ winter13pg11.html
  2. Source: NIAMS (NIH): Health_Info/ Knee_Problems/ default.asp
  3. Source: MeSH (U.S. National Library of Medicine)
  4. Source: MedLinePlus Magazine (NIH): magazine/ issues/ winter13/ articles/ winter13pg11.html
  5. ibid.
  6. Source: NCI Thesaurus
  7. Source: NIAMS (NIH): Health_Info/ Arthritis/ arthritis_rheumatic.asp
  8. Source: NIAMS (NIH): Health_Info/ Knee_Problems/ default.asp
  9. Source: MedLinePlus (NIH): ankleinjuriesanddisorders.html
  10. Source: NIAMS (NIH): Health_Info/ Knee_Problems/ default.asp

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Note: This site is for informational purposes only and is not medical advice. See your doctor or other qualified medical professional for all your medical needs.