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Ligaments, tendons, and joints

This video presents the structure and functions of ligaments, joints, and tendons. Created by Tracy Kim Kovach.

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  • blobby green style avatar for user Niloufar Khanna
    if arthritis is an autoimmune disease, how do the immune cells attack the cartilage if no blood goes to it?
    (11 votes)
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  • male robot donald style avatar for user Florent Dusanter
    at you mentionned the presence of a "synovial fluid".
    Does it mean that the "capsule" have to be hermetic ?
    If yes, what is happening when there is a leak ? Deterioation of articular carthilage ?
    Thanks for the responses
    (5 votes)
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    • female robot grace style avatar for user Christina F
      My anatomy professor said; synovial fluid is constantly, but slowly being replenished think of the way water in a pool is not typically drained completely but is gradually replaced. When a joint is damaged and synovial fluid is lost it will be replaced but it takes a long time for the capsule to refill to its original volume.
      (4 votes)
  • leafers tree style avatar for user Cody
    What is the difference between Ligaments and Tendons?
    (0 votes)
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  • leaf blue style avatar for user HunHan
    How can I easily understand ACL and PCL? Also there mechanism of injury
    (2 votes)
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    • leaf blue style avatar for user dysmnemonic
      ACL is attached anteriorly on the tibial plateau and posteriorly on the femur, and it stops the tibia moving forward relative to the femur. The traditional mechanism of injury for ACL is a strong rotational force applied on a weight bearing knee.

      PCL attaches to the tibia posteriorly, and to the femur anteriorly, and it stops the tibial plateau moving backwards off the femoral condyles. The typical mechanism for PCL injury is force applied at the top of the tibia, directed backwards.
      (4 votes)
  • old spice man green style avatar for user LGPorter10
    how is oshgood slaughters formed?
    (2 votes)
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  • blobby green style avatar for user Manar Al-Masri
    What is the type of knee joint? Is it a hinge joint?
    (1 vote)
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  • blobby green style avatar for user bclem
    Is the composition of ligaments and tendons different in hyperflexible individuals (e.g., contortionists) compared to the general population? For example, are the intervertebral discs more elastic in individuals who can do deep backbends?
    (3 votes)
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  • leaf orange style avatar for user donestrage
    how can i learn the anatomy of the human skeleton? ie: naming and placement of bones, different types of bones, etc.
    (1 vote)
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    • leafers ultimate style avatar for user Brian Etges
      There is a really good app for iOS (and potentially for Android, but I'm unsure) that is called TinyCards. It's an app that teaches you things using flashcards, and there are several completed sets of flashcards of the entire skeletal anatomy. I'm suggesting this because this is what I used to learn memorise all 206 bones in the human body. Hope it helps! :))
      (4 votes)
  • boggle blue style avatar for user x.asper
    What word would be the opposite of avascular?
    (1 vote)
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    • leaf green style avatar for user Joanne
      Vascular, means with or having vessels, i.e. circulation. Avascular means not having vessels or circulation. This change of meaning due to the letter 'a' often makes students unhappy, you are not alone. "A" in front of a word often means 'away' or opposite because of Latin roots to our words. When teaching, I often say there is "typical" and "atypical", there is "normal" or "abnormal", the list goes on, but you understand the point. You have to watch the prefix when defining a word and a small change can mean a big difference. Footnote, he reviews this concept around in the transcript. Reading the transcript can help when trying to understand the 'video'. And, as he says, the fact that ligaments and cartilage are avascular means they do not heal well if torn or damaged. Best of luck.
      (3 votes)
  • boggle green style avatar for user yibo
    What is the difference between articular cartilage and hyaline cartilage?
    (1 vote)
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    • piceratops ultimate style avatar for user Hecretary Bird
      Hyaline cartilage provides support for our body, while articular cartilage acts as sort of a shock absorber, lessening the impacts of the friction between bones. Hyaline is found on the nose and ribs, as well as the larynx and trachea, and it is filled with collagen, which is a structural protein. Articular cartilage has a high water content, but I'm not sure exactly how this helps cushion bones.
      Edit: Please look at Tybalt's comment under this reply, it shows the actual difference between the types of cartilage.
      (3 votes)

Video transcript

- [Instructor] So, ligaments and tendons are types of extra strong and dense connective tissues. Ligaments connect bones to other bones, and tendons connect muscle to bone. And the point where one bone articulates or meets up with another is called a joint. Now, there are different types of joints found throughout the body, and the first type is called synarthroses, which are immovable joints where two bones are fused together. For example, you'll find these types of joints in the skull. When you were a baby, your skull was made up of a bunch of different pieces that grew as your brain grew. And then, as an adult, the joints between these bones then fused and became synarthroses. The next type of joint is called an amphiarthroses. Amphi- meaning it's both stiff but also slightly movable. And an example of amphiarthroses would be your vertebral joints. And then finally, we have what are synovial joints, which are also known as diarthroses, of which there are a couple different types. One type, for example, is the ball and socket synovial joint, and you'll find examples of ball and socket joints in your shoulders or in your hips. These are joints that have many degrees of motion. And then, another type of synovial joint is the hinge joint. An example of a hinge joint would be, say, your elbow or your knee where that joint pretty much moves in just one plane, like the hinge of a door. Now, synovial joints are named so because they are lubricated by a fluid called synovial fluid, which is contained within the synovial capsule that surrounds the whole joint. Now, the surfaces of bones that meet up in a joint are lined by a special kind of smooth cartilage called articular cartilage, which is composed of specifically hyaline cartilage. And articular cartilage, like all cartilage, is avascular, meaning it lacks any sort of vasculature or blood vessels. And so, it has a hard time getting the nutrients it needs to heal and recover if it were to become damaged by overuse or infection. And as you might be somewhat familiar with, the overuse of joints over time can lead to inflammation, which is called arthritis, from arth- meaning joint, and -itis meaning inflammation. And this can lead to permanent destruction of articular cartilage, which causes the pain and stiffness of arthritis.