What is the Difference Between Meniscus and Cartilage

The main difference between meniscus and cartilage is that meniscus is the crescent-shaped fibrocartilaginous structure, partly dividing the joint cavity, whereas cartilage is a strong, flexible connective tissue that protects the bone.

Generally, the meniscus and cartilage are two protective structures that occur in joints. Both are resilient, soft-type connective tissue.

Key Areas Covered

1. What are Meniscus
– Definition, Characteristics, Importance
2. What are Cartilage
– Definition, Characteristics, Importance
3. Similarities Between Meniscus and Cartilage
– Outline of Common Features
4. Difference Between Meniscus and Cartilage
– Comparison of Key Differences

Key Terms

Cartilage, Meniscus

What is Meniscus

The meniscus is a crescent-shaped, fibrocartilage structure that partly divides the joint cavity. Meniscus occurs in the knee, wrist, acromioclavicular, sternoclavicular, and temporomandibular joints in humans. In addition, the meniscus refers to the cartilage in the knee that contains both the lateral and the medial meniscus. Both the lateral and the medial meniscus provide structural integrity to the knee in tension and torsion.

Figure 1: Medial and Lateral Meniscus

Both are two pads of fibrocartilaginous tissue that disperse the friction of the knee joint. They have a concave shape on the top and flat on the bottom, articulating between the femur and the tibia. Moreover, the blood flow of the meniscus is from the periphery to the central meniscus. The meniscus disperses the weight of the body, reducing friction during movement in the knee joint.

What is Cartilage

Cartilage is a flexible, fibrous connective tissue that mainly occurs in the larynx, respiratory tract, external ear, and articulating surface of the joints. Moreover, hyaline cartilage, fibro cartilage, and elastic cartilage are the three types of cartilage that occur in humans. Normally, the hyaline cartilage is smooth and shiny. The most common type of cartilage is hyaline cartilage, and it is found in the nose, respiratory tract, and joints. The hyaline cartilage in joints is also called the articular cartilage. In addition, the two major functions of the articular cartilage are to serve as a shock absorber and allow the smooth movement of the bones at joints. On the other hand, the articular cartilage stores the synovial fluid, which lubricates and nourishes the joints. However, the regenerative capacity of the articular cartilage is low.

Figure 2: Cartilage Types

Moreover, the fibro cartilage is found in the knee, and it is much tough and inflexible. In addition, the elastic cartilage is the most flexible cartilage, and it is found in the ear, epiglottis, and larynx.

Similarities Between Meniscus and Cartilage

• Meniscus and cartilage are two types of protective tissue that occur inside joints.
• Moreover, they are made up of resilient, soft connective tissue.
• In addition, the main function of the meniscus and cartilage is to stabilize articulation and absorb shock.

Difference Between Meniscus and Cartilage

Definition

Meniscus refers to thin fibrous cartilage between the surfaces of some joints, e.g. the knee while cartilage refers to a firm, flexible connective tissue found in various forms in the larynx and respiratory tract, in structures such as the external ear, and in the articulating surfaces of joints.

Contains

Usually, the meniscus contains softer fibrocartilage while cartilage contains chondrocytes, specialized cartilage cells that produce a matrix of collagen, proteoglycans, and other non-collagenous proteins.

Occurrence

Meniscus occurs in the knee, wrist, acromioclavicular, sternoclavicular, and temporomandibular joints while cartilage occurs in the articulating surfaces of bones in synovial joints, and in the ribs, nose, trachea, bronchi, larynx, and growth plates.

Function

The main function of the meniscus is to increase stability for femorotibial articulation, distribute the axial load, absorb shock, and provide lubrication and nutrition to the knee joint while the main function of cartilage is to resist compressive forces, enhance bone resilience, and provide support on bony areas where there is a need for flexibility.  

Conclusion

In brief, meniscus and cartilage are two types of protective tissue that occur in joints. They are made up of soft, connective tissues. Generally, the meniscus contains softer fibrocartilage while cartilage contains chondrocytes that secrete the extracellular matrix consisting of collagen, proteoglycans, and other non-collagenous proteins. In addition, the meniscus occurs in the knee, wrist, acromioclavicular, sternoclavicular, etc. joints while cartilage occurs in the synovial joints, ribs, nose, trachea, bronchi, larynx, etc. The main function of the meniscus is to stabilize the joints and absorb shock. while, the main function of the cartilage is to resist compressive force, enhance bone resilience, and provide support to the bone. Therefore, the main difference between meniscus and cartilage is the structure and function.

References:

1. “Knee Meniscus: Function & Injuries – Knee Pain Explained.” Knee
2. Mandal, Dr. Ananya. “What Is Cartilage?” News, 26 Feb. 2019.

Image Courtesy:

1. “Braus 1921 284” By Braus, Hermann – Own work (Public Domain) via Commons Wikimedia
2. “Cartilage types” By Shiloh117981894 – Own Work (CC BY-SA 4.0) via Commons Wikimedia