Necessary for movement, posture, and protection of internal organs, the human skeletal system encompasses all of the bones, every joint, and corresponding ligaments. It also includes all of the tendons, which are responsible for attaching muscles to bones. Healthy skeletal systems are known to exhibit a high bone density as well as an aligned spine and a typical range of motion. The young child who demonstrates normal growth patterns and gross motor skills is considered to have a healthy skeletal system.
A healthy skeletal system encompasses a high bone mineral density (BMD), referring to a measure of the level of minerals inside of bone. Individuals who have diets containing calcium and vitamin D, while also obtaining adequate sunlight, contribute to their bone mass as these nutrients taken together help to maintain efficient blood calcium levels. Those deficient in nutrients important to bone development and strength could incur harmful diseases such as rickets and osteoporosis, a condition causing weakened bone tissue with increased propensity to fracture. Osteoporosis, a disease usually presenting later on in life, can be prevented with proper dieting and doing exercises which call for weight-bearing such as hiking and climbing stairs.
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Presenting with a straight vertebral column, the healthy skeletal system shows proper articulation of the vertebra, though there are certain conditions that cause abnormal spine curvatures such as with scoliosis and kyphosis. Resulting in an "S" curve of the spine, scoliosis manifests during the adolescent stage of development and, with progression, could eventually cause respiratory system problems. Kyphosis manifests as a hunchback curvature and is generally due to other skeletal conditions such as osteoporosis and traumatic spinal injuries.
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Measurable using a device referred to as a goniometer, range of motion (ROM) pertains to the limits to which joints are capable of moving. Demonstrating a normal range of motion in all of its joints, the healthy skeletal system will exhibit different results according to the sex and age of the individual being tested. Goniometry can also determine skeletal system abnormalities and progression of certain conditions such as arthritis and hemophilia.
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In order for kids to be able to crawl, walk, and grip objects effectively, they must have made it to definite milestone points of skeletal and muscular development. Balance and coordination abilities increase as their head size changes, becoming smaller in relation to the remainder of their bodies. Young kids create more strength and grow taller as they improve on the activities requiring movement from one place to another. The motor development of a young human being is prompted by his or her association with the outside world.