Main content
High school biology
Course: High school biology > Unit 8
Lesson 3: The musculoskeletal system- Skeletal structure and function
- Cartilage
- Ligaments, tendons, and joints
- Three types of muscle
- Anatomy of a skeletal muscle cell
- LeBron Asks: What muscles do we use when shooting a basket?
- The musculoskeletal system review
- The musculoskeletal system
© 2023 Khan AcademyTerms of usePrivacy PolicyCookie Notice
Ligaments, tendons, and joints
This video presents the structure and functions of ligaments, joints, and tendons. Created by Tracy Kim Kovach.
Want to join the conversation?
- if arthritis is an autoimmune disease, how do the immune cells attack the cartilage if no blood goes to it?(11 votes)
- The immune cells in the blood can escape from the blood vessel that they are in, and travel through tissue. Once in the tissue, the immune cells can attack the cartilage.(3 votes)
- atyou mentionned the presence of a "synovial fluid". 1:50
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)- 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)
- What is the difference between Ligaments and Tendons?(0 votes)
- How about histologically speaking? What are the differences? Will I see fibroblasts in one of them etc(1 vote)
- How can I easily understand ACL and PCL? Also there mechanism of injury(2 votes)
- 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.(5 votes)
- why are tendons inelastic?(3 votes)
- how is oshgood slaughters formed?(2 votes)
- Osgood Schlatters Disease is a wear and tear disease, typically found in children where the is an overuse.(3 votes)
- What is the type of knee joint? Is it a hinge joint?(1 vote)
- 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)
- how can i learn the anatomy of the human skeleton? ie: naming and placement of bones, different types of bones, etc.(1 vote)
- 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)
- What word would be the opposite of avascular?(1 vote)
- 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 aroundin 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. 2:06(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.