Table of ContentsView AllTable of ContentsDefinitionAnatomyCommon ProblemsHealth Tips
Table of ContentsView All
View All
Table of Contents
Definition
Anatomy
Common Problems
Health Tips
The musculoskeletal system is the body’s support structure. It is a matrix of bones, muscles, and joints that provides stability and protection and allows you to move. The musculoskeletal system is dynamic and constantly remodeling itself to keep you healthy.
Research shows that up to 40% of the musculoskeletal system’s load-bearing capacity is lost within weeks of inactivity.The musculoskeletal system weakens with age, too, increasing the risk of injuries and musculoskeletal diseases likeosteoarthritis. Regularexercisethroughout your life is crucial for keeping your musculoskeletal system healthy.
This article takes a closer look at the function and anatomy of the musculoskeletal system. It details a variety of conditions that can affect this system, along with tips to keep your musculoskeletal system healthy.
MoMo Productions / Getty Images
What Is the Musculoskeletal System?
Among its many important functions, the musculoskeletal system:
Anatomy of the Musculoskeletal System
The musculoskeletal system is an interconnected network of features that each boast their own structures, functions, and roles. To understand how the musculoskeletal system works as a whole, you will need to be familiar with its parts.
Bones
There are 206 bones in the adult human body. Bones consist of a hard outer part made of proteins (mostlycollagen) andhydroxyapatite(mostly calcium and other minerals). The inner portion of bone, called trabecular bone, is softer than the hard outer cortical bone, but it still is necessary for maintaining bone strength.
While the structure of all bone is the same, the bones perform various functions in the body:
Why Do Babies Have More Bones than Adults?
Muscles
There are two kinds of muscle that are part of the musculoskeletal system: skeletal muscles and smooth muscles. The third type of muscle,cardiac muscle, is not part of the musculoskeletal system.
Skeletal musclesare:
Smooth musclesare:
There’s more to muscles than keeping you strong. When you exercise, your skeletal muscles emit proteins called myokines that:Regulate body weightReduce inflammationIncrease insulin sensitivitySuppress tumor growthImprove cognitive function
There’s more to muscles than keeping you strong. When you exercise, your skeletal muscles emit proteins called myokines that:
The Anatomy of the Lower Leg Muscles
Cartilage
The ends of the bone that form a joint are covered with a connective tissue calledcartilage. Normal cartilage is smooth, flexible, and tough. Cartilage is composed of collagen, water, and proteins calledproteoglycans.
Cartilage serves to:
Joints
Thejointsare where the ends of two or more bones come together. While there are joints that do not move, such as the joints between the plates of the skull, most joints are capable of facilitating movement. There are two types of joints that facilitate movement: synovial joints and cartilaginous joints.
Synovial jointsare:
Cartilaginous jointsare:
Joints are enclosed in a joint capsule which has a lining (synovium). Cells of the synovium produce synovial fluid which nourishes the cartilage and helps to reduce friction during movement.
Ligaments
Ligamentsare tough, fibrous bands of tissue that connect bone to bone. They are composed of collagen and elastic fibers, which give them a rubberband-like stretchability.
Ligaments:
Tendons
Tendonsare similar to ligaments, except rather than connecting bone to bone, tendons connect muscle to bone. These tough, fibrous bands of tissue are primarily made of collagen.
Tendon’s primarily perform the following functions:
Tendons are usually found within a sheath (the tendon sheath), which allows them to move friction-free. A tendon sheath has two layers: the supportive and protective fibrous tendon sheath, and the synovial sheath, which produces synovial fluid to lubricate joints.
Bursae
Bursae(the plural form of bursa) are small, fluid-filled sacs that:
Bursae vary in size depending on their location. The largest bursa in the body is the subacromial respective subdeltoid bursa, located between the acromion, deltoid, and therotator cuff tendonsof the shoulder.
What Health Conditions Affect the Musculoskeletal System?
Musculoskeletal conditions are the leading cause of disability worldwide, affecting at least 1.7 billion people. There are more than 150 musculoskeletal conditions, including the following:
Conditions Affecting Bones
Musculoskeletal conditions affecting bones include the following:
Osteoporosisis a condition in which bone density decreases, resulting in weak, brittle bones. People with osteoporosis have a greater risk of bone fractures. Most people with osteoporosis are post-menopausal women and men with low testosterone.
Fragility fracturesaffect roughly half of all women and one-quarter of all men at some point in life. Fragility fractures are fractures that occur when a person falls from standing height or less. An injury like this means that your bones are weaker than normal, typically due to another underlying condition like osteoporosis. The hip, spine, and wrist are the most common sites of fragility fractures.
Conditions Affecting Muscles
The following musculoskeletal conditions affect muscles:
Sarcopeniais the involuntary loss of muscle strength and mass, most often due to aging and lack of physical activity. Beginning at age 30, the body naturally starts to lose about 3% to 5% of muscle mass each decade. While this is normal, poor nutrition and lack of exercise can expedite muscle loss and result in sarcopenia.
Muscle strainoccurs when a muscle is overstretched, causing muscle fibers to tear. This is often called a “pulled muscle.” Muscle strains range from mild, in which the muscle is tender but has not lost strength, to severe, in which the muscle separates from the tendon and loses function. Muscle strains most often occur during contact sports like football, and sports that require quick starts, like tennis.
Muscular dystrophyis a group of genetic muscular diseases that causes progressive muscle loss. Muscular dystrophies worsen over time. Eventually, many people with muscular dystrophy lose their ability to walk. Some muscular dystrophies appear in childhood, while others start later in life.
Conditions Affecting Joints
Various musculoskeletal conditions affect joints:
Rheumatoid arthritisis a chronic inflammatory disease in which the immune system attacks its own tissues, causing inflammation around joints and sometimes organs. The condition causes pain, stiffness, and swelling in the joints. Most people with rheumatoid arthritis start to notice symptoms in their 30s to 50s.
Psoriatic arthritisis another form of inflammatory arthritis that affects some people with psoriasis, an autoimmune skin and nail disease. Psoriatic arthritis causes joint pain, stiffness, and swelling, most commonly in the fingers and toes. There are several forms of psoriatic arthritis, such as symmetrical polyarthritis, which closely resembles rheumatoid arthritis.
What Is the Most Common Musculoskeletal Condition?Low back pain is the most common musculoskeletal condition, affecting at least 619 million people worldwide. It is the leading cause of disability and is most prevalent in women ages 50 to 55 years. Low back pain may begin suddenly or develop gradually. The exact cause of low back pain is unclear in about 90% of cases.
What Is the Most Common Musculoskeletal Condition?
Low back pain is the most common musculoskeletal condition, affecting at least 619 million people worldwide. It is the leading cause of disability and is most prevalent in women ages 50 to 55 years. Low back pain may begin suddenly or develop gradually. The exact cause of low back pain is unclear in about 90% of cases.
What Could Be Causing My Musculoskeletal Pain?
Keeping Your Musculoskeletal System Healthy
You can’t prevent every musculoskeletal injury or disease. But you can take steps to keep your musculoskeletal system strong and reduce your risk of preventable conditions:
Summary
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