Joints: Definition, Anatomy, Movement, Types, Function
Joints are points of articulation between two or more bones that enable movement and provide stability to the human body. Based on structure and function, joints are classified into fibrous, cartilaginous, and synovial types with varying degrees of mobility. This guide explains the definition, classification, examples, functions, disorders, diagrams, FAQs, and NEET-level MCQs on joints.
This Story also Contains
- What Is a Joint?
- Structural Classification of Joints
- Functional Classification of Joints
- Importance of Joints in the Human Body
- Advantages of Studying Joints
- Joints NEET MCQs (With Answers & Explanations)
- Recommended Video on Joints
What Is a Joint?
Joints are primary parts of the human body that enable any kind of movement and ensure stability. They connect the bones, making every living creature capable of moving. From gestures to challenging athletic moves, the types and functions of joints are highly relevant and must be learned while understanding human anatomy and physiology.
Structural Classification of Joints
Joints are structurally classified based on the material that holds the bones together.
Fibrous Joints
These joints are immovable and possess fibrous connective tissue that tightly connects bones. They are located at places in the body where more stability and support are needed, such as in the skull.
Cartilaginous Joints
Cartilaginous joints are joined by cartilage and allow limited movement. They include synchondroses, which are temporary and thus are a type of epiphyseal growth plate, and symphyses, which are permanent and connect bones in the pelvic girdle, such as the pubic symphysis.
Synovial Joints
Synovial joints have a relatively large range of motion compared to other forms of joints. Synovial joints, by their very nature, contain an enclosed cavity filled with synovial fluid. In such joints, one finds a wide degree of movement about the limbs and spine.
Functional Classification of Joints
Functional classification is focused on the degree and type of movements that are permitted. These include
Ball and Socket Joints
The ball and socket joints have the greatest range of motion, including rotation movements, which involve remodelling. Examples include the hip and shoulder joints.
Pivot Joints
Pivot joints are those that permit rotational motion around a central axis. An example is the joint between the atlas and axis vertebrae in the neck.
Hinge Joints
Hinge joints move in one plane, similar to the action of a door hinge. Examples are the elbow and knee joints.
Saddle Joints
Saddle joints are very flexible, for they allow movement in two planes. The wrist joint at the base of the thumb is an example of a saddle joint.
Condyloid Joints
The movement that is possible in condyloid joints includes flexion, extension, abduction, and adduction in two planes. Examples are the radiocarpal and metacarpophalangeal joints.
Gliding Joints
Gliding joints allow flat or slightly curved bones to slide against or alongside one another. They are articulated in the wrists and ankles.
Importance of Joints in the Human Body
The importance of joints in the human body are:
Enable all kinds of movements
Support body posture
Allow locomotion in human body
Important for daily activities and sports
Advantages of Studying Joints
Understanding the types and functions of joints is necessary for many aspects connected to medicine, sports science, and rehabilitation. It leads to the diagnosis and treatment of disorders of the joints, designs ergonomic tools and methods, and is effective in athletic performance.
Joints NEET MCQs (With Answers & Explanations)
Important questions asked in NEET from this topic are:
Classification of joints
Examples of each type of joints
Practice Questions for NEET
Q1. Force generated by muscles is used to carry out movement through joints , where joint acts as
Load
Effort
Lever
Fulcrum
Correct answer: 4) Fulcrum
Explanation:
With the help of contraction, muscles produce force, which causes movement at joints, which serve as fulcrums. Movement around the joint is caused by the contraction of muscles tugging on lever-like bones. This enables a variety of bodily functions, including walking, lifting, running, and even fine motor skills like typing or writing. In the elbow joint, for instance, the forearm serves as the lever, the biceps muscle produces the force (effort), and the elbow serves as the fulcrum.
Hence, the correct answer is option 4) Fulcrum.
Q2. Knee joint and elbow joints are examples of
Saddle joint
Ball and socket joint
Pivot joint
Hinge joint
Correct answer: 1) Second and seventh rib
Explanation:
Similar to how a hinge controls a door's opening and shutting, hinge joints only permit movement in one direction. The finger and toe joints are additional instances of hinge joints.
Elbow joint: The lower arm's ulna and radius bones enable the elbow to hinge. But these bones can also spin around one another because they are connected by a pivot joint.
The knee joint is responsible for the knee's ability to bend and extend.
Hence, the correct answer is option 4) Knee joints and elbow joints are examples of hinge joints.
Q3. What is the type of movable joint present between the atlas and axis?
Pivot
Saddle
Hinge
Gliding
Correct answer: 1) Pivot
Explanation:
Pivot joint: Between atlas and axis called atlanto-axial joint. The atlantoaxial joint allows rotational movement of the head, enabling the "no" motion of the neck. It is a specialized pivot joint where the odontoid process (dens) of the axis fits into the atlas, allowing for the rotation of the skull. This joint plays a crucial role in head mobility and flexibility.
Hence, the correct answer is option 1) Pivot.
Also Read:
Recommended Video on Joints
Frequently Asked Questions (FAQs)
Joints are connective parts between bones that provide motion and mechanical support to the skeleton.
The three general types of joints are fibrous, cartilaginous, and synovial.
Synovial joints are the most common joint type in the body. They are characterized by a synovial cavity filled with synovial fluid, which lubricates and nourishes the joint.
Hinge joints allow movement only in one plane, somewhat like a door hinge, enabling bending and straightening.
Gliding joints are found where bones tend to slide past one another, as at the wrists and ankles.