Introduction
A joint is mainly known for making connections between bones in the body and these joints link the whole skeleton system and form a functional unit which helps in movement of body parts. Some of the common joints are knee, elbow and shoulder joints and have capability to withstand compression and maintain heavy load work by bearing load on joints. While the joints which are between bone and skull allow very normal and minor movements, to protect brain and other sense organs from sudden jerk. Apart from this there is one more joint between the tooth and the jawbone which is known as gomphosis.
Hinge Joints
Hinge joints are those joints that allow movement in one plane only. They do bending and straightening work such as flexing fingers. Hinge joint is covered by protective covering that covers the bones and thick gel known as synovial fluid is present between joints and they work as lubricants and allow movement of joints smoothly. These types of joints contain muscles, ligaments and other types of tissue that stabilize the joint and their movements. Their stability is more than ball and socket joints which include shoulder and hip joints. In comparison to hinge joint ball and socket joint allow a greater range of movement and flexibility in more than one plane.
Features of Hinge Joints
1. Hinge joint show similarity with hinge on a lid of a box.
2. Movement of hinge joints is in one plane i.e they can not show movement in more than one plane.
3. Formation of the hinge joint takes place by fitting the convex surface of one bone to the concave surface of another bone.
4. Movement of ball and socket joints is different from hinge joints as ball and socket joints show movement along more than one plane.
5. Hinge joints also have chances of dislocation even when they are known to be stable.
6. By maintaining a healthy diet, reducing stress, frequent movement and strengthening muscles around the joints, one can maintain a healthy hinge joint.
Types of Hinge Joints
There are several types of hinge joints:
1. The Elbow: This joint shows connection with the upper portion of the arm i.e humerus to the two bones in the lower arms which are radius and ulna. This joint is also called a humeroulnar joint i.e this joint is situated between a notch in the ulna and a notch in the humerus.
2. The Jaw: It is also a kind of hinge joint that allows us to open and close our mouth. It is not actually a hinge joint but movement of mouth is due to the hinge joint. Like the knee and ankle their mouth also show rotatory movement.
3. The Hand: Interphalangeal joints are known for connecting our fingers together. This joint is known for their importance as use of hand in our daily life is very important. Our hands have three sets of joints: metatarsophalangeal joints, proximal interphalangeal joints and distal interphalangeal joints.
4. The Foot: Just like hands, feet also have interphalangeal joints. They contain two planters tendons. In looks our toes are little different from our fingers, but their functions are similar to fingers and they show both flexion and extension movements.
5. The Knee: The main function of knees is to attach our thighs to our legs. They are known to be the largest joint in our body. Knee allows side to side movement rather than simply flexion and extension movement.
6. The Ankle: Ankle joint is commonly known as talocrural region and they help in movement of feet at the ankles. It also allows some side to side movement. Ankle joint is made up of three different joints, they are: talocrural joint, subtalar joint and tibiofibular joint.
Yes or No Type Questions
1. Hinges joints show movement in more than one plane?
Answer: No
2. Side to side movement is shown by the knee hinge joint?
Answer: Yes
3. Are interphalangeal joints known for connecting our fingers together?
Answer: Yes
4. The foot is the largest hinge joint?
Answer: No
FAQs on Hinge Joints
1. What exactly is a hinge joint and how does it work in the body?
A hinge joint is a type of synovial joint that functions much like the hinge on a door. It allows bones to move back and forth along one single plane, providing for movements like bending and straightening. These joints are filled with synovial fluid, which acts as a lubricant to ensure smooth motion.
2. What are the main movements that a hinge joint can perform?
Hinge joints primarily allow for two types of movement: flexion, which is the action of bending the joint (like closing your elbow), and extension, which is the action of straightening it (like opening your elbow fully). This limited range of motion provides great stability.
3. What are some common examples of hinge joints in the human body?
You can find several important hinge joints throughout your body. The most common examples include:
- The elbow joint, connecting the upper arm to the forearm.
- The knee joint, which is the largest joint in the body.
- The ankle joint (talocrural joint), allowing you to move your foot up and down.
- The interphalangeal joints in your fingers and toes, which let them bend and straighten.
4. How can I understand a hinge joint using a simple, real-world example?
Think of a door hinge. A door can only swing open and shut in one direction; it cannot move up, down, or sideways. A hinge joint in your body, like your knee or elbow, works in the exact same way, allowing for a simple back-and-forth motion but restricting other movements.
5. Why is a hinge joint more stable than a ball-and-socket joint?
A hinge joint is more stable because its movement is restricted to a single plane (back-and-forth). The structure of the bones and strong ligaments limit side-to-side motion. In contrast, a ball-and-socket joint, like your shoulder, allows for a wide range of motion in multiple directions, making it less stable and more prone to dislocation.
6. If the knee is a hinge joint, why can't it bend backwards?
The knee cannot bend backwards, a movement called hyperextension, because of the way the bones (femur and tibia) are shaped and because of strong ligaments inside and around the joint. Specifically, the anterior cruciate ligament (ACL) becomes tight when the knee is straight, preventing it from bending the wrong way and causing injury.
7. Besides bones, what other parts make a hinge joint work properly?
Several tissues work together to support a hinge joint. Cartilage covers the ends of the bones to reduce friction. A joint capsule surrounds the joint, and it's lined with a membrane that produces lubricating synovial fluid. Finally, strong ligaments and muscles around the joint provide stability and control its movement.
