Synovial Joints and Arthritis
A joint is where two bones meet. Ligaments and tendons hold joints together. The synovial joint is where a portion of the bone is coated with articular cartilage and lubricated with synovial fluid. The soft padding between the bones referred to as cartilage helps reduce friction. Cartilage is the key to healthy joints.
Cartilage is composed of the following:
- Collagen
- Proteoglycan
- Chondrocyte
There are three types of joints. These include freely moveable joints, partially moveable joints, and immovable joints. Synovial joints (freely moveable joints) make up 90% of our body. Synovial joints allow a large range of motion, and encompass wrists, knees, ankles, shoulders, and hips. The inner lining of synovial joint is called the synovium. The whole joint capsule consists of a tough outer layer which helps stabilize the joint and an inner membrane that produces the lubricating synovial fluid. Synovial joints are further broken into groups according to shape and movement.
This subgroup includes:
- Hinge joints (elbows)
- Ball and Socket joints (hips)
- Condyloid joints (knee)
- Pivot joints (elbow)
- Saddle joints (thumb)
- Gliding joints (fingers, wrist)
All of the above joints are commonly affected by arthritis. Rheumatoid arthritis mostly affects the synovial joints. Elderly suffering from Osteoarthritis can also experience severe pain and inflammation in the synovial joints. |