Passing Around Some Joint Knowledge

HEY.. let’s keep it clean. I am talking about the joints on the human body.

If you don’t understand what constitutes a joint, HOW can you know “what to watch for“?

For example, one of signs and symptoms of psoriatic arthritis according to BeJointSmart.org is

Pain, swelling, or stiffness in one or more joints

A joint is where two bones come together.

Did you know that two bones NEVER directly touch each other!

Professor Fink’s Lesson on Arthrology; The Joints Of The Body is a fantastic listen.
Part 1
Part 2

FUN FACT:  The MOST MOVABLE joint in the body is the shoulder.

I will try and break down what I learned in Professor Fink’s lecture series.

What is IN BETWEEN the joints IS what determines the joint type.

Here are 3 Anatomic joint classifications
(classification type focused on in the lecture)

1. Fibrous connective tissue joints
Fibrous connective tissue IS BETWEEN the two bones.
Generally none-to-slight movement between bones.

THREE TYPES of fibrous connective tissues joints:

  • Suture joint- Two bones come together and a thin layer of fibrous connective tissue. There is no movement.
    WHERE is it found? Between the bones of the skull.
  • Syndesmosis joint- A membrane. A broad sheet of connective tissue.
    WHERE is it found? A fibroid sheet is found between the radius and ulna bones.
  • Gomphosis joint- Periodontal ligament.
    WHERE is it found? A joint between a tooth and the socket

 

FUN FACT: Professor Fink says there is NO SUCH THING as double jointed! WHAT? You don’t have EXTRA joints!

2. Cartilaginous joints
Cartilage IS BETWEEN the two bones.
Generally none or slight movement.

TWO TYPES of Cartilaginous joints

  • Synchondrosis joint- Hyaline cartilage between the two bones.
    WHERE is it found? Between the end of the bone and the shaft there is a epiphyseal plate or hyaline cartilage. AND it is found in the Sternocostal joint (The joints between the ribs and the sternum is hyaline cartilage)
  • Symphysis joint- Fibrocartilage between bones.
    WHERE is this fibrocartilage found? Between the vertebral joints (intervertebral discs) AND the pubic symphysis (between where the two pubic bones come together there is fibrocartilage)

 

FUN FACT: There IS NO evidence that cracking your joints makes you more prone to arthritis. When you are cracking your knuckles, you are causing a rapid change in pressure in the synovial fluid creating a SNAP, CRACKLE  and  POP sound.

3. Synovial joints (Most common classifications of joints)
Synovial fluid IS BETWEEN the two bones.
Generally there is a lot of movement.
* IF all you have between two bones is fluid, IT MAY slam together leading to bleeding, therefore, hyaline cartilage protects and prevents bleeding. Bones are held together by ligaments called the “fibrous capsule”. The ligaments circle the joint forming a “fibrous capsule” around the synovial joint.
* The synovial fluid itself is clear and Professor Fink says the consistency is similar to raw egg whites.

FOUR TYPES of synovial joints

  • Limited movement synovial joints – Not a lot of movement permitted between two bones.
    Where: Between carpal bones of the wrist and between talus bones of the ankle.
  • Uniaxial movement synovial joints- hinge joints which allow flexion and extension. Pivot joints- medical and lateral rotation
    Where- elbow, knee, fingers and toes.
  •  Biaxial movement synovial joints- movement in 2 planes
    Where: wrist (radial-carpal)
  • Multiaxial movement synovial joint- permit circumduction movement. Ball- and socket joints
    Where: Shoulder and hip joints (most moveable joints in the body)

 

FUN FACT: The knee joint is the largest, most complex, and the most commonly injured joint in the body.

I found this NICE visual break down of synovial joints over at Teachpe.com

Types of Joints

Types of Joints-2

THREE types of arthritis covered in lecture:

 1. Rheumatoid arthritis:  Auto-immune condition. The person’s immune system attacks the joints. Most common in women.

Treatment options- corticoid steroid options. WHY? They are immunosuppressant drugs.

2. Gout arthritis: Metabolic (biochemical) disorder. High levels of uric acid develops in the body. This is known as hyperuricemia. Uric acid is a waste product. Old nucleic acids are converted in the body to uric acid which is secreted in your urine. In people with gout they have high level of uric acid which then accumulates in the joints. It is mainly accumulated in the big toe.

Treatment option- Allopurinol.  Which is a drug that works to reduce the production of uric acid in the body.

3. Osteoarthritis: Caused by repeated injury or trauma to the joint. Common in athletes. Joint breaks down from repeated injury

Treatment option-NSAIDs.

Much love,
Marissa

 

P.S. Be kind to your joints and and read this article on the Top 10 ways to protect your joints.