Locomotor system

The bones

1. BY- NIHARIKA VERMA LOCOMOTOR SYSTEM

2. LOCOMOTOR SYSTEM Locomotor system is necessary for the movement of body. It consists of Skeleton Joints Muscles

3. LOCOMOTOR SYSTEM The musculoskeletal system (also known as the locomotor system) is an organ system that give animals (including humans) the ability to move, using the muscular and skeletal systems. It provides form, support, stability, and movement to the body. The musculoskeletal system is made up of the body’s bone (the skeleton), muscles, cartilage(connect bones to bones), tendons(connect muscle to bone), ligaments joints (movements of joints) and other connective tissues that support and binds tissue and organs together.

4. LOCOMOTOR SYSTEM It primary function include supporting the body, allowing motion, and protecting vital organs. The bones of the skeletal system provide stability to the body analogous to a reinforcement bar in concrete construction. Muscles keep bones in place and also play a role in their movement. To allow motion, different bones are connected by articulating joints, and cartilage prevents the bone ends from rubbing directly into each other. There are about 600 muscles in human body. The three main type of muscle included skeletal, smooth, and cardiac. The brain, nerves and skeletal muscles together to cause movement known as the Neuromuscular System.

5. It is flexible connective tissue, which connects two bones or muscles to holds a joint together. Join bone to bone, or muscle to muscle. Found in joints. It is inelastic cord of fibrous tissue, which attaches the muscle to bone. Joints muscle to bone. Found in skeletal muscle. LIGAMENTS TENDONS

6. Smooth muscle Smooth (or visceral muscle)- it is involuntary muscle. - Forms the muscle layers in the walls of the digestive tract, bladder, various ducts, arteries and veins, and other internal organs. Smooth muscles cells are elongated and thin, have only one nucleus, and form sheets rather than bundles of muscles. Smooth muscle is controlled by the autonomic nervous system (ANS).

7. Cardiac muscle Cardiac (or heart muscle) – a cross between the smooth and striated muscles, make up the heart tissue. This is a unique tissue found in the wall of the heart. Like smooth muscle, it is controlled by the autonomic nervous system (ANS).

8. Skeletal muscle Skeletal (or voluntary/striated muscle)- it is most abundant tissue, in the human body or vertebrae, it produces movement of various bones of the skeleton. Each skeletal muscle fiber is roughly cylindrical, contains many nuclei, and is crossed by alternating light and dark bands called Striations. Fibers bind together, via connective tissue, into bundles, and these bundles, in turn, bind together to form muscles. Thus, skeletal muscles are composite structures composed of many muscle fibers, nerves, blood vessels, and connective tissue. Skeletal muscles are controlled by the somatic nervous system (SNS). It is directly involved in breathing process.

9. Skeletal System The human skeletal system consists of all the bones, cartilage, tendons and ligaments in the body. An adult’s skeleton contains 206 bones. Children skeletons contains more bones because some of them including those of the skull, fuse together as they grow up. The male skeleton is usually longer and has a high bone mass. The female skeleton, on the other hand, has a broader pelvis to accommodate for pregnancy and child birth. The skeletal system can be broken down into two parts, known as the AXIAL SKELETON and APPENDICULAR SKELETON.

10. Functions of Skeletal System Protecting internal organs from injury. Allowing for movement. Produce blood cell. Storing minerals and nutrients.

11. AXIAL SKELETAL SYSTEM The axial skeletal forms the central axis of the body of the skull, ossicles of the middle ear, hyoid bone of the throat, vertebral column, and the thoracic cage (rib cage). The function of the axial skeleton is to provide support and protection for the brain, the spinal cord, and the organs in the ventral body cavity. It provides a surface for the attachments of the muscles that move the head, neck, and trunk, performs respiratory movements, and stablizes parts of the appendicular skeleton.

12. The axial skeleton which forms the longitudinal axis of the body it is divided into 3 parts: The skull The vertebral column The bony thorax

13. The skull It is formed by 2 sets of bone CRANIUM and FACIAL BONES. The cranium encloses and protects the fragile brain tissue and is composed of eight large flat bones. CRANIUM BONES Parietal (2) – side of the head Temporal (2) – for ears Frontal (1) – forehead Occipital (1) – back of the head Ethmoid (1)- inner bone Sphenoid (1) – base of the skull

14. FACIAL BONE Maxilla (2) – upper jaw Mandible (1) – lower jaw Zygomatic (2) – cheek bone Nasal (2) – nose Palatine (2) – mouth Inferior nasal Concha (2) – inside nose Lacrimal (2) – tear fland Vomer (1) – thinner bone in the middle of nasal cavity

15. The Vertebral Column The vertebral column, also called the spine, spinal column or backbone. Composed of series of bones called vertebrae (singular is vertebra). Region of the vertebral column – 7 cervical vertebrae (C1-C7) 12 thoracic vertebrae (T1-T12) 5 lumber vertebrae (L1-L5) 1 sacrum (5fused) 1 coccyx (4 fused) * The sacrum and coccyx do not have number. * Total number of vertebrae during early development in 33. * As a child grows, several vertebrae in the sacral and coccygeal regions fuse. * Sacrum and coccyx bone become fused.

16. The vertebral column is a series of approximately 33 bones called vertebrae, which each region characterized by a different vertebral structure. The cervical, thoracic, and lumber vertebrae – movable. Sacrum and coccyx – immovable Between adjacent vertebrae from the second cervical vertebrae to the sacrum are it inter vertebral disc (inter-between). FUNCTIONS: The vertebral column has four main functions Protection – encloses and protects the spinal cord within the spinal canal. Support – carries the weight of the body above the pelvis. Axis- forms the central axis of the body Movement- has roles in both posture and movement. 71 cm (28 in)- adult male, 61 cm (24 in)- adult female.

17. The Body Thorax Also known as Thoracic cage (sternum and ribs). Thoracic cage is a skeletal framework which supports the thorax. It is nature is osteo cartilaginous and elastic. The thoracic vertebrae, ribs, costal cartilages, and sternum form the thoracic cage. It gives protection for the internal organs of the thoracic cavity and supports the superior trunk, pectoral gridle , and upper limbs. It has significant role play for raising or reducing the intra thoracic pressure to ensure mechanism of respiration.

18. RIBS The ribs area set of twelve paired bones which form the protective ‘cage’ of the thorax. They articulate with the vertebral column posteriorly , and terminate anteroily as cartilage (known as costal cartilage). COSTAL CARTILAGE The anterior ends of first 7 ribs are joined to the sternum via their costal cartilages. The cartilages at the anterior ends of 8 th ,9 th , and 10 th ribs are joined to the next higher cartilage. The anterior ends of 11 th and 12 th ribs are free and hence named floating ribs. STERNUM Central bone of the chest. The clavicle and ribs 1 to 7 articulate with the sternum. Comprised of the manubrium , the sternum body and xiphoid process.

19. APPENDICULAR SKELETON SYSTEM It includes the bones of the shoulder girdle, the upper limbs, the pelvic girdle, and the lower limbs. The pectoral or shoulder girdle consists of the scapulae and clavicles. The shoulder girdle connects the bones of there upper limbs to the axial skeleton. These bones also provide attachment for muscles that move the shoulders and upper limbs. The upper limbs include the bone of the arm ( humerous ), forearm (radius and ulna) , wrist and hand. The only bone of the arm is the humerous , with articulates with the forearm bones – the radius and ulna, at the elbow joint. The ulna is the larger of two forearm bones.

20. Wrist bones- The wrist, or carpus , consists of eight carpal bones. The eight carpal bones of the wrist are the scaphoid , lunate , triquetral , pisiform , trapezoid, trapezium, capitate , hamate . Hand bones- the hand includes 8 bones in the wrist, 5 bones that form the palm, and 14 bones that form the fingers and thumb. The wrist bones are called carpals. The bone that form the palm of the hand are called metacarpals. The phlanges are the bones of the fingers. The pelvic girdle is a ring of bones of the lower limb to the axial skeleton. The pelvic girdle consists of the right and left hip bones. Each hip bone is a large, flattened, and irregularly shaped fusion of three bones: the Ilium, Ischium , and pubis.

21. The lower limbs include the bones of the thigh, leg, and foot. The femur is the only bone of the thigh. It articulates with the two bones of the leg the larger tibia (commonly known as the shin) and smaller fibula. The thigh and leg bones articulate at the knee joint that is protected and enhances by the patella bone that supports the quadriceps tendon. The bones of the foot include the tarsus, metatarsus, and phlanges . Foot Bones: the bones of the foot consist of the tarsals bones of the ankles, the planges that form the toes, and the metatarsals that give the foot its arch. As in the hand, the metatarsals, five proximal phlanges , five distal phlanges , but only four middle phlanges (as the foot’s , big toe has only two phlanges ).

22. Ankle bones: The ankle, or tarsus, consists of seven tarsal bones: the calcaneus , talus, cuboid , navicular , and three cuneiforms. Foot arches: The arches of the foot care formed by the interlocking bones and ligaments of the foot. They serve as shock – absorbing structures that supoort body weight and distribute stress evenly during walking. - The longitudinal arch of the foot runs from the calcaneus to the heads of the metatarsals, and has medial and lateral parts. The transverse arch of the foot runs across the cuneiforms and the base of the metatarsal bones.

23. JOINTS It is the meeting of 2 bones or more in the skeletal system. Arthrology is the science of studying joints. A joint or articulation is the place where two bones come together. Joint classified into two : ( i ) Functional Classification (ii) Structural Classification

24. . Focuses on the amount of movement allowed, immovale freely movable. Focuses on the material that binds the joint together. Fibrous joint – immovale Cartilaginous joints – slightly movable Synovial joints – Freely Movable FUNCTIONAL CLASSIFICATION STRUCTURAL CLASSIFICATION

25. JOINTS (Structural Classification) Fibrous or fixed Joint– Immovale connect bones, no movement (skull and pelvis) Cartilaginous Joints – Slightly movable bones are attached by cartilage a little movement (spine or ribs cartilage) Synovial Joints – Freely movable, much more movement than cartilaginous joints. Cavities between bones are filled with synovial fluid. This fluid help lubricate and protect the bone.

26. Types of Synovial Joints : i . Ball and Socket Joints: It allows the greatest range of movement. In this type of joint, head of bone is fits into a socket of another bone. Held together by ligaments and tendons. Example: Shoulder and hip joints. ii. Hinge Joints: It allow flexion and extension with only a small amount of rotation. Example: Elbow, knee, ankle, finger, toes. iii. Pivot Joint: It allows only rotation. Example: Proximal and destal radio ulner joint.

27. iv. Gliding Joints: In this joint the articular surface of bone it looks flat and move on the another bone in sliping movement. Example: Sternoclavicular joint and joint between carpal and tarsal bone. v. Saddle Joints: The saddle joints allow the movement of the joint forward and backward and right to left. Example: Wrist joint.