Unit 8- Assignment A- Musculoskeletal system PDF

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BTEC Applied Science Unit 8: Musculoskeletal System AssignmentArslan MahmoodTable of ContentsA. P1 - Explain the functional role of the musculoskeletal system in the human body. .............................................................................................................................

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Structure and Function of the Musculoskeletal System

Arslan Mahmood

BTEC Applied Science Unit 8: Musculoskeletal System Assignment

Arslan Mahmood 1

Structure and Function of the Musculoskeletal System

Arslan Mahmood

Table of Contents A.

P1 - Explain the functional role of the musculoskeletal system in the human body...................3

............................................................................................................................................................. 14

A. P2 - Describe the effect of disorder of muscles and joints and possible corrective treatment(s). ......................................................................................................................................................... 17

A. M1 - Compare how disorders of the musculoskeletal system can affect how muscles bring about movement of joints and the importance of corrective treatment..................................21

D1 Evaluate the effect of corrective treatment(s) associated with a musculoskeletal disorder34

Bibliography:................................................................................................................................... 39

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Structure and Function of the Musculoskeletal System

Arslan Mahmood

A. P1 - Explain the functional role of the musculoskeletal system in the human body. Introduction: The musculoskeletal system provides form, stability and movement to the human body. It consists of the body's bones (which make up the skeleton), muscles, tendons, ligaments, joints, cartilage and other connective tissue. The term "connective tissue" is used to describe the tissue that supports and binds tissues and organs together. Its chief components are collagen and elastic fibres, which are composed of different proteins. The bones of the skeletal system serve to protect the body's organs, support the weight of the body and give the body shape. The muscles of the muscular system attach to these bones, pulling on them to allow for movement of the body. The human skeleton: The skeleton consists of the bones of the body. For adults, there are 206 bones in the skeleton. Younger individuals have higher numbers of bones because some bones fuse together during childhood and adolescence to form an adult bone. The primary functions of the skeleton are to provide a rigid, internal structure that can support the weight of the body against the force of gravity and to provide a structure upon which muscles can act to produce movements of the body. The lower portion of the skeleton is specialised for stability during walking or running. In contrast, the upper skeleton has greater mobility, ranges of motion and features that allow you to lift and carry objects. In addition to providing for support and movements of the body, the skeleton has protective and storage functions. It protects the internal organs, including the brain, spinal cord, heart, lungs and pelvic organs. The bones of the skeleton serve as the primary storage site for important minerals such as calcium and phosphate. The bone marrow found within bones stores fat and houses the blood-cell producing tissue of the body. The human skeleton is divided into two parts: the axial skeleton and the appendicular skeleton. Figure 1:

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Structure and Function of the Musculoskeletal System

Arslan Mahmood

The axial skeleton forms the vertical, central axis of the body and includes all bones of the head, neck, chest and back. It serves to protect the brain, spinal cord, heart and lungs. It also serves as the attachment site for muscles that move the head, neck and back and also for muscles that act across the shoulder and hip joints to move their corresponding limbs. The axial skeleton of the adult consists of 80 bones, including the skull, the vertebral column and the thoracic cage. The skull is formed by 22 bones. Also associated with the head are an additional seven bones, including the hyoid bone and the ear ossicles (three small bones found in each middle ear). The vertebral column consists of 24 bones, each called a vertebra, also the sacrum and coccyx. The thoracic cage includes the 12 pairs of ribs and the sternum, the flattened bone of the anterior chest. The appendicular skeleton includes all bones of the upper and lower limbs, also the bones that attach each limb to the axial skeleton. There are 126 bones in the appendicular skeleton of an adult. The muscles of the body: Figure 2:

Figure 3:

Name

in sport

Deltoid

tion in a

Pectoralis major

of a press up 4

Structure and Function of the Musculoskeletal System

Arslan Mahmood

(moving the arm towards the body); Shoulder horizontal flexion (moving the arms forwards in front of the body) Triceps

Extend the elbow (straightening the arm)

Shooting in netball

Biceps

Flex the elbow (bending the arm)

Drawing a bow in archery

External obliques

Trunk rotation (turning the body sideways)

Turning the body to breathe to the side when performing front crawl in swimming

Latissimus dorsi

Shoulder adduction (moving the arm towards the body); Shoulder horizontal extension

Butterfly stroke in swimming

Hip flexors

Hip flexion (moving knee up towards the chest)

Performing a rugby conversion kick

Gluteus maximus

Hip extension (moving the leg backwards)

Pulling back leg before kicking a ball

Quadriceps

Extend the knee (straightening the leg)

Kicking a ball

Hamstrings

Flex the knee (bending the leg)

Performing a hamstring curl on a weights machine

Gastrocnemius

Plantar flexion of the ankle (pointing the toes downwards)

Standing on tiptoe to mark a goal shoot in netball

Tibialis anterior

Dorsiflexion of the ankle (bringing the toes up towards the shin)

Foot making contact with a football

Muscles transfer force to bones through tendons. They move our bones and associated body parts by pulling on them – this process is called muscle contraction. One muscle of the pair contracts to move the body part, the other muscle in the pair then contracts to return the body part back to the original position. Muscles that work like this are called antagonistic pairs. In an antagonistic muscle pair as one muscle contracts the other muscle relaxes or lengthens. The muscle that is contracting is called the agonist and the muscle that is relaxing or lengthening is called the antagonist.

The following groups of muscles are antagonistic pairs: Biceps

Triceps

Hamstrings

Quadriceps

Gluteus maximus

Hip flexors 5

Structure and Function of the Musculoskeletal System

Gastrocnemius

Tibialis anterior

Pectoralis major

Latissimus dorsi

Arslan Mahmood

To allow antagonistic pairs to work efficiently, other muscles called fixators assist by supporting and stabilising the joint and the rest of the body. Some fixators also assist the agonist and act as a synergist. The trapezius muscle can act as a fixator when the biceps is flexing the elbow joint. The abdominals can act as fixators to stabilise the body for hip and knee movements.

1. Flat Bones Protect Internal Organs Figure 4:

There are flat bones in the skull (occipital, parietal, frontal, nasal, lacrimal and vomer), the thoracic cage (sternum and ribs) and the pelvis (ilium, ischium and pubis). The function of flat bones is to protect internal organs such as the brain, heart and pelvic organs. Flat bones are somewhat flattened and can provide protection. 2. Long Bones Support Weight and Facilitate Movement Figure 5:

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Structure and Function of the Musculoskeletal System

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The long bones, longer than they are wide, include the femur (the longest bone in the body) as well as relatively small bones in the fingers. Long bones function to support the weight of the body and facilitate movement. Long bones are mostly located in the appendicular skeleton and include bones in the lower limbs (the tibia, fibula, femur, metatarsals and phalanges) and bones in the upper limbs (the humerus, radius, ulna, metacarpals and phalanges).

3. Short Bones Are Cube-shaped Figure 6:

Short bones are about as long as they are wide. Located in the wrist and ankle joints, short bones provide stability and some movement. The carpals in the wrist (scaphoid, lunate, triquetral, hamate, pisiform, capitate, trapezoid and trapezium) and the tarsals in the ankles (calcaneus, talus, navicular, cuboid, lateral cuneiform, intermediate cuneiform and medial cuneiform) are examples of short bones.

4. Irregular Bones Have Complex Shapes Figure 7:

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Structure and Function of the Musculoskeletal System

Arslan Mahmood

Irregular bones vary in shape and structure and therefore do not fit into any other category (flat, short, long, or sesamoid). They often have a fairly complex shape, which helps protect internal organs. For example, the vertebrae, irregular bones of the vertebral column, protect the spinal cord. The irregular bones of the pelvis (pubis, ilium and ischium) protect organs in the pelvic cavity.

5. Sesamoid Bones Reinforce Tendons Figure 8:

Sesamoid bones are bones embedded in tendons. These small, round bones are commonly found in the tendons of the hands, knees, and feet. Sesamoid bones function to protect tendons from stress and wear. The patella, commonly referred to as the kneecap, is an example of a sesamoid bone. Overall Functions of the Musculoskeletal System:  

 



The musculoskeletal system’s primary functions include supporting the body, allowing motion and protecting vital organs. To allow motion, different bones are connected by articulating joints. Cartilage prevents the bone ends from rubbing directly on to each other while the muscles contract to move the bones associated with the joint. Produce blood cells: Red blood cells, white bloo+d cells, and other blood elements are produced in the red marrow, which fills the internal cavities of many bones. Protect body organs: Many soft tissues and organs are surrounded by skeletal elements. For example, the rib cage protects the heart and lungs, the skull protects the brain, the vertebrae protect the spinal cord and the pelvis protects the delicate reproductive organs. Store minerals and lipids: Calcium is the most abundant mineral in the body. (Ninety-nine percent of the body's calcium is found in the skeleton.) The calcium salts of bone are a valuable mineral reserve that maintains normal concentrations of calcium and phosphate ions in body fluids. The bones of the skeleton also store energy reserves as lipids (fats) in areas filled with yellow marrow.

Major Joints in the body:

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Structure and Function of the Musculoskeletal System

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Joints – “the point at which two or more bones connect, can be fixed, slightly movable, or freely movable.” The musculoskeletal system also contains connective structures and tissues that support the body and allow for its movement. Each joint reflects a compromise between stability and range of motion. For example, the bones of the skull are very stable but with little motion, whereas the shoulder joint allows for a full range of motion but is a relatively unstable joint. Tendons: These attach muscle to bone. Ligaments: These attach bone to bone. Skeletal muscles: These muscles contract to pull on tendons and move the bones of the skeleton. Skeletal muscles also:   

Maintain posture and body position; Support soft tissues; Guard entrances and exits to the digestive and urinary tracts; and, Maintain body temperature.

Nerves: Nerves control the contraction of skeletal muscles, interpret sensory information and coordinate the activities of the body's organ systems. Cartilage: This is a type of connective tissue. It is a firm gel-like substance. The body contains three major types of cartilage: hyaline cartilage, elastic cartilage, and fibrocartilage. Hyaline cartilage is the most common type of cartilage. It provides stiff but somewhat flexible support. Examples in adults include the tips of ribs (where they meet the sternum) and part of the nasal septum. Another example is articular cartilage, which covers the ends of bones within a joint. The surfaces of articular cartilage are slick and smooth, which reduces friction during joint movement. Elastic cartilage provides support but can tolerate distortion without damage and return to its original shape. Elastic cartilage can be found in the external flap of the ear, among other places. Fibrocartilage resists compression, prevents bone-to-bone contact and limits relative movement. Fibrocartilage can be found within the knee joint, between the pubic bones of the pelvis and between the spinal vertebrae. Cartilage heals poorly and damaged fibrocartilage in joints such as the knee can interfere with normal movements. The knee contains both hyaline cartilage and fibrocartilage. The hyaline cartilage covers bony surfaces; fibrocartilage pads in the joint prevent contact between bones during movement. Injuries to the joints can produce tears in the fibrocartilage pad and the tears do not heal. Eventually, joint mobility is severely reduced. There are three main types: fibrous, cartilaginous and synovial. The latter allows the greatest freedom of movement and are the most well known in anatomy. There are several types of synovial joints:    

Pivot Ball and socket Condyloid Saddle 9

Structure and Function of the Musculoskeletal System  

Arslan Mahmood

Hinge Plane

There are many joints in the entire human body, usually named according to the bones forming them. However, there are several major joints that are more complex than the rest and are extremely important in anatomy. These are the skull sutures, temporomandibular, shoulder, elbow, wrist, hip, knee, and ankle joints. They are reinforced by ligaments for extra support. Fibrous Joints - The bones of fibrous joints are held together by fibrous connective tissue. There is no cavity, or space, present between the bones and so most fibrous joints do not move at all, or are only capable of minor movements. There are three types of fibrous joints: sutures, syndesmoses, and gomphoses. Sutures are found only in the skull and possess short fibres of connective tissue that hold the skull bones tightly in place.

Figure 9:

Syndesmoses are joints in which the bones are connected by a band of c for more movement than in a suture. An example of a syndesmosis is the joint of the tibia and fibula in the ankle.

Cartilaginous joints are joints in which the bones are connected by cartilage. There are two types of cartilaginous joints: synchondroses and symphyses. In a synchondrosis, the bones are joined by hyaline cartilage. Synchondroses are found in the epiphyseal plates of growing bones in children. In symphyses, hyaline cartilage covers the end of the bone but the connection between bones occurs through fibrocartilage. Symphyses are found at the joints between vertebrae. Either type of cartilaginous joint allows for very little movement.

Synovial joints are the only joints that have a space between the adjoining bones (Figure 3). This space is referred to as the synovial (or joint) cavity and is filled with synovial fluid. Synovial fluid lubricates the joint, reducing friction between the bones and allowing for greater movement. The ends of the bones are covered with articular cartilage, a hyaline cartilage, and the entire joint is surrounded by an articular capsule composed of connective tissue that allows movement of the joint while resisting dislocation. Articular capsules may also possess ligaments that hold the bones together. Synovial joints are capable of the greatest movement of the three structural joint types; however, the more mobile a joint, the weaker the joint. Knees, elbows, and shoulders are examples of synovial joints.

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Structure and Function of the Musculoskeletal System

Arslan Mahmood

Figure 10:

Types of S Synovial jo structure o These join

nd e joint. oints.

Figure 11:

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Structure and Function of the Musculoskeletal System

Arslan Mahmood

Different types of joints allow different types of movement. Planar, hinge, pivot, condyloid, saddle, and ball-and-socket are all types of synovial joints.

Planar Joints Planar joints have bones with articulating surfaces that are flat or slightly curved faces. These joints allow for gliding movements and so the joints are sometimes referred to as gliding joints. The range of motion is limited in these joints and does not involve rotation. Planar joints are found in the carpal bones in the hand and the tarsal bones of the foot, as well as between vertebrae.

Figure 12:

The joints of the carpal bones in the wrist are examples of planar joints. Hinge Joints In hinge joints, the slightly rounded end of one bone fits into the slightly hollow end of the other bone. In this way, one bone moves while the other remains stationary, like the hinge of a door. The elbow is an example of a hinge joint. The knee is sometimes classified as a modified hinge joint. Figure 13:

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Structure and Function of the Musculoskeletal System

Arslan Mahmood

The elbow joint, where the radius articulates with the humerus, is an example of a hinge joint. Pivot Joints Figure 14:

The joint in the neck that allows the head to move back and forth is an example of a pivot joint. Pivot joints consist of the rounded end of one bone fitting into a ring formed by the other bone. This structure allows rotational movement, as the rounded bone moves around its own axis. An example of a pivot joint is the joint of the first and second vertebrae of the neck that allows the head to move back and forth. The joint of the wrist that allows the palm of the hand to be turned up and down is also a pivot joint. Condyloid joints consist of an of another bone. This is also s movement along two axes, as side and up and down.

imilarly oval-shaped hollow pe of joint allows angular which can move both side to

Figure 15:

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Structure and Function of the Musculoskeletal System

Arslan Mahmood

The metacarpophalangeal joints in the finger are examples of condyloid joints. Saddle joints are so named because the ends of each bone resemble a saddle, with concave and convex portions that fit together. Saddle joints allow angular movements similar to condyloid joints but with a greater range of motion. An example of a saddle joint is the thumb joint, which can move back and forth and up and down, but more freely than the wrist or fingers. Figure 16:

The carpometa Ball-and-socke another bone. directions. Exa

cuplike socket of re possible in all

Figure 17:

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Structure and Function of the Musculoskeletal System

Arslan Mahmood

This shoulder joint is an example of a Ball-and-socket joint.

Movement at Synovial Joints The wide range of movement allowed by synovial joints produces different types of movements. ...