themusculo-skeletalsystem-240219160347-3dc220c1.pptx

1st Semester Physiology The Musculo- Skeletal System By Thiru murugan. M  Unit – 8: Physiology - Musculoskeletal system Bones - Functions, movements of bones of axial and appendicular skeleton, Bone healing Joints and joint movements Alteration of joint disease Pr...

1st Semester Physiology The Musculo- Skeletal System By Thiru murugan. M  Unit – 8: Physiology - Musculoskeletal system Bones - Functions, movements of bones of axial and appendicular skeleton, Bone healing Joints and joint movements Alteration of joint disease Properties and Functions of skeletal muscles – mechanism of muscle contraction Structure and properties of cardiac muscles and smooth muscles Application and implication in nursing  Functions of the Skeletal System or bones: 1. Movement: involving varies movements according to the purpose of activities 2. Attachment for muscles: provides points of attachment for muscles. 3. Support: The backbone is the main support center for the upper body. 4. Protection: protection of internal organs. (skull protect brain, ribs protect lungs and heart) 5. Makes Blood: Red and white blood cells are formed from bone marrow. 6. Storage: Bones store minerals, such as calcium and phosphorus. 7. Provides shape & framework of the body 8. Formation of joints 9. Maintain posture & balance  Movements of bones of axial and appendicular skeleton: Movements of bones of axial skeleton: The function of the axial skeleton is to provide support and protection for the brain, the spinal cord, and the organs in the thoracic cavity. It provides a surface for the attachment of muscles that move the head, neck, and trunk, performs respiratory movements, and stabilizes parts of the appendicular skeleton. Skull movements for vision, hearing &other purposes Vertebrae movements – maintain posture Thoracic cage movements – for respiration  Movements of bones of appendicular skeleton The appendicular skeleton consists of upper and lower limbs and girdles. The bones that provide support and space for the movement of limb bones. Formation of different joints & enables them for movements This part of the skeleton system comprises of bones of the upper limbs (movement of forearms and shoulders) Lower limbs (helps in motion), Pectoral girdle (support the upper limbs), Pelvic girdle (protect the vital organs of the abdominal cavity and transfer the weight to the lower limbs).  Bone healing: Bone healing is a regenerative process in which bone is restored without scar tissue formation. Also called fracture healing Bone fractures are a common injury and the healing process is complex. Bone is one of a few tissues that is able to heal without forming a fibrous scar. There are two types of fracture healing: 1. Direct healing (primary) 2. Indirect (secondary) Bone healing take place through different stages  Direct/ primary healing occurs when the bony fragments are fixed together with compression. There is no callus formation. The bony ends are joined and healed by osteoclast and osteoblast activity. Indirect healing is more common than direct healing and involves both endochondral and intramembranous bone healing. Anatomical reduction and stable conditions are not required for indirect healing to occur. Rather, there is a small amount of motion and weight-bearing at the fracture, which causes a soft callus to form, leading on to secondary bone formation.  Stages of bone healing: i) Hematoma formation: Blood vessels in the broken bone tear and hemorrhage, resulting in the formation of clotted blood, or a hematoma, at the site of the break. The severed blood vessels at the broken ends of the bone are sealed by the clotting process. Bone cells deprived of nutrients begin to die.  ii) Bone generation: Within days of the fracture, capillaries grow into the hematoma, while phagocytic cells begin to clear away the dead cells. Though fragments of the blood clot may remain, fibroblasts and osteoblasts enter the area and begin to reform bone. Fibroblasts produce collagen fibers that connect the broken bone ends, while osteoblasts start to form spongy bone. The repair tissue between the broken bone ends, the fibro cartilaginous callus is composed of  iii)Bony callous formation: The fibro cartilaginous callus is converted into a bony callus of spongy bone. callus - a type of soft bone replaces the blood clot that formed in the inflammatory stage. The callus holds the bone together, but isn't strong enough for the body part to be used. Over the next few weeks, the soft callus becomes harder. It takes about two months for the broken bone ends to be firmly joined together after the fracture. This is  iv) Bone remodeling: The bony callus is then remodelled by osteoclasts and osteoblasts, with excess material on the exterior of the bone and within the medullary cavity being removed. Compact bone is added to create bone tissue that is similar to the original, unbroken bone. This remodeling can take many months; the bone may remain uneven for years Stages of bone healing:  Factors Affect Bone Healing Patient with nutritional deficits, smoking, and diabetic patient will experience delayed bone healing. Parathyroid hormones have a vital role in bone healing Aging process affect bone healing Chronic inflammation delay the bone healing Infection of the fracture site at healing process. Insufficient formation of cartilage within fracture gap and marrow space. Open, comminuted fracture, and the extent of soft tissue injury also show delayed union healing Joint movement Joint movements are generally divided into four types: gliding, angular, rotation, and circumduction Gliding: Gliding is the simplest type of motion. It is one surface moving over another without any rotary or angular motion. This motion exists between two adjacent surfaces. Angular: Angular motion decreases or increases the angle between two adjoining bones. The more common types of angular motion are as follows:  Flexion: Bending the arm or leg. Extension: Straightening or unbending, as in straightening the forearm, leg, or fingers. Abduction: Moving an extremity away from the body. Adduction: Bringing an extremity toward the body Rotation: A movement in which the bone moves around a central point without being displaced, such as turning the head from side to side. Circumduction: The movement of the hips and shoulders. Other Types of Movement: Supination: Turning upward, as in placing the palm of the hand up. Pronation: Turning downward, as in placing the palm of the hand down or placing sole of the foot to the outside. Inversion: Turning inward, as in turning the sole of the foot inward. Eversion: Turning outward, as in turning the sole of the foot outward.  Properties and Functions of skeletal muscles:  Properties of skeletal muscle:  Excitability: muscle tissue - able to react to nervous stimulation.  Extensibility: ability of muscle tissue to lengthen when contracting  Elasticity: ability of muscle tissue to return to its normal resting length once it has been stretched.  Contractility: this refers to the capacity of a muscle to contract or shorten forcibly when stimulated by nerves and hormones Function of skeletal muscles: Body movement (locomotion): skeletal muscles enable humans to move and perform daily activities. They play an essential role in respiratory mechanism Help in maintaining posture and balance. They also protect the vital organs in the body. Involve in Communication (verbal and facial) Production of body heat (thermogenesis) Helping Chewing and swallowing Playing essential role in Formation and  Mechanism of Muscle contraction or Neuro muscular transmission for muscle contraction: Definition: it is defined as the process of transferring the information from motor nerve ending to the muscle fibers through NMJ. It is the mechanism by which the motor nerve impulses initiate muscle contraction. A series of events takes place during this process. Resting membrane potential: The membrane potential of a neuron at rest—that is, a neuron not currently receiving or sending messages is negative, typically around -70 millivolts (mV), This is called the resting membrane potential. Action potential: Action potentials (those electrical impulses that send signals around your body) are nothing more than a temporary shift (from negative to positive) in  Process of Muscle Contraction When action potential reaches the nerve terminal, the pre synaptic membrane become highly permeable to Ca+ The large amount of Ca+ enter into synaptic cleft This Ca+ causes release of Acetylcholine into Synaptic Cleft The Acetylcholine binds with nicotinic receptors (present in Post Synaptic membrane), which initiates the muscle contraction Once action potential is over, Acetylcholine is destroyed by Enz called “Acetyl cholinesterase”  Structure and properties of cardiac muscles and smooth muscles The properties of the cardiac muscle are: 1. Rhythmicity 2. Excitability 3. Contractility 4. Conductivity. 1. Rhythmicity/Automaticity/Chronotropism: It is the ability of the cardiac muscles to initiate impulses spontaneously, without external electrical stimulation from the nervous system. 2. Excitability (Bathmotropism): it is the ability of cardiac muscle to respond to adequate stimuli by generating an action potential. 3. Contractility/Inotropism: It is the ability of the cardiac muscle to convert electrical energy into mechanical work (contraction). 4. Conductivity (Dromotropism): It is the ability of cardiac muscle fibers to conduct the cardiac impulses that are initiated in the SA node (the pacemaker of the heart) Contraction of Cardiac muscle:  It consist Specialized modified Cardiomyocytes known as pacemaker cells.  Cardiac pacemaker cells carry the impulses that are responsible for the beating of the heart.  They are distributed throughout the heart and are responsible for generating and conducting electrical impulses to contract and relax.. The pacemaker cells control heart rate and determine how fast the heart pumps blood. Cardiac muscle also contains specialized cells known as Purkinje fibers for the rapid conduction of electrical signals.  They contract on their own intrinsic rhythms without any external stimulation. Similarities between skeletal and cardiac muscle: Cardiac Features Skeletal muscles muscle Myofibrils Yes Yes Striations Yes Yes Capillary Yes Yes network Actin & Yes Yes Myosin A & I band Yes Yes Difference between skeletal and cardiac muscle: Features Skeletal muscles Cardiac muscle Location: Bone Heart Nucleus Peripheral Central Cell type: Multi nucleated Uninucleated Shape of cells: Bundles Branched Intercalated No Yes disc Control: Voluntary Involuntary Neurogenic Contraction: Conductive system contraction Length : Longer Short Function: Movements Pumping of blood  Function of Cardiac muscle  Rapid, involuntary contraction and relaxation of the cardiac muscle are vital for pumping blood throughout the cardiovascular system.  It maintain Bp within blood vessels  Structure and properties of smooth muscles Smooth muscle consists of thick and thin filaments that are not arranged into sarcomeres giving it a non-striated pattern. On microscopic examination, it will appear homogenous. Smooth muscle cytoplasm contains a large amount of actin and myosin. Actin and myosin act as the main proteins involved in muscle contraction  Contraction of smooth muscle: Smooth muscle contraction is caused by the sliding of myosin and actin filaments (a sliding filament mechanism) over each other. Smooth muscle-containing tissue needs to be stretched often, so elasticity is an important attribute of smooth muscle. Single-unit smooth muscle consists of multiple cells connected through connexins (gap junction protein) that can become stimulated in a synchronous pattern from only one synaptic input.  Connexins allow for cell-to-cell communication between groups of single- unit smooth muscle cells. This intercellular communication allows ions and molecules to diffuse between cells giving rise to calcium waves. This unique property of single-unit smooth muscle allows for synchronous contraction to occur. Multi-unit smooth muscle, each smooth- muscle cell receives its own synaptic input, allowing for the multi-unit smooth muscle to  Functions of Smooth Muscle: Gastrointestinal tract - propulsion of the food bolus Cardiovascular - regulation of blood flow and pressure Renal - regulation of urine flow Genital - contractions during pregnancy, propulsion of sperm Respiratory tract - regulation of breathing Integument - raises hair with erector pili muscle Sensory - dilation & constriction of the pupil,  Alterations in disease - bones: Congenital Diseases of Bone: Congenital diseases of bone range from localized malformations to hereditary disorders associated with abnormalities affecting the entire skeletal system. Can result in the absence of bones, extra bones, or inappropriately fused bones; these are typically due to mutations in genes Achondroplasia: Achondroplasia refers to a syndrome of short- limbed dwarfism and macrocephaly  Scoliosis is an abnormal lateral curvature of the spine, usually affecting adolescent girls. Kyphosis refers to an abnormally excessive convex curvature of the spine as it occurs in the thoracic Lordosis is the inward curve of the lumbar spine (just above the buttocks). Osteogenesis Imperfecta: it refers to a group of genetic disorders affects the skeleton, joints, ears, ligaments, teeth, sclerae and skin. It is characterized by hard and easily broken bones  Fractures: The fracture is the most common bone problem; it is the discontinuity of the bone. Osteonecrosis: it refers to death of bone in the absence of infection. Osteomyelitis: Osteomyelitis is an inflammation of the bone and the bone marrow. Tuberculosis of Bone: Tuberculosis of bone originates from the lung or lymph nodes, and reaches the bone by haematogenous spread. Osteoporosis: it is “porous bone” that increase sponginess of the bone, causes bones to become weak and brittle. Osteomalacia: it refers to a softening of bones, often caused by vitamin D deficiency in adults. Rickets is the softening and weakening of bones in children, usually because of an extreme and prolonged vitamin D deficiency. Paget’s disease: Paget disease (osteitis deformans) is a localized disorder of bone remodelling, resulting in thickened but weak bone that is susceptible to deformity and fracture. Benign tumours of bone: Osteoma is a benign neoplasm that frequently involves the skull and facial bones. Osteoid Osteoma: Osteoid Osteoma is a benign, painful growth of the diaphysis of a long bone, often Osteoblastoma: Osteoblastoma is a tumour that is similar to an osteoid osteoma but is larger (>2 cm) and often involves vertebrae. Osteochondroma: Osteochondroma (exostosis) is a benign bony metaphyseal growth capped with cartilage that originates from epiphyseal growth plate. Osteosarcoma: Osteosarcoma (osteogenic sarcoma) is the most common primary malignant tumour of bone. Alterations in disease – Joints: Arthritis. Inflammation of joints. Arthritis may cause joint pain and swelling. Lupus. This autoimmune disease affects many parts of the body and can cause joint and muscle pain. Some types of lupus often cause arthritis. Dislocated joints. A joint is dislocated when the bones are pushed or pulled out of position. A joint dislocation is a medical emergency. Osteoarthritis: It is the most common disease of joints. It is caused due to wear and tear of cartilage present between joints. It results in pain, stiffness and swelling. Rheumatoid arthritis: Rheumatoid arthritis is an autoimmune disorder. Here, one’s own immune system attacks the healthy cells causing inflammation and pain in joints. Gout: Gout or gouty arthritis is a type of metabolic disorder. It is caused due to high levels of uric acid in the body or hyperuricemia. Uric acid crystals get deposited in joints. It causes pain and inflammation - leads to deformities. Bursitis: It is the inflammation of the synovial bursa, that is  Alterations in disease - muscles Muscle strain or pulled muscle, occurs when your muscle is overstretched or torn. Muscle sprain is a stretch or tear in a ligament. A strain is also a stretch or tear, but it happens in a muscle or a tendon. Tendons link muscles to the bones. Myasthenia gravis (MG) is a long-term neuromuscular disease that leads to varying degrees of skeletal muscle weakness. The most commonly affected muscles are those of the eyes, face, and swallowing. It can result in double vision, drooping eyelids, trouble talking, and trouble walking.  Muscular dystrophy is a group of inherited diseases that damage and weaken your muscles over time. Rigor mortis is a stiffening of the body muscles after death due to chemical changes in their myofibrils. Muscle fibrillation abnormal and irregular muscle contraction due to destruction of motor nerve. Muscle fasciculations or muscle twitches are small, rapid, involuntary contractions in skeletal muscles that are too weak to move a limb Tetanus: also known as lockjaw, is a bacterial infection characterized by muscle spasms. In the most common type, the spasms begin in the jaw and then progress to the rest of the body.  Muscle spasms (muscle cramps) are painful contractions and tightening of your muscles due to involuntary and forceful contraction. Wry neck or torticollis is a painfully twisted and tilted neck. The top of the head generally tilts to one side while the chin tilts to the other side Diaphragmatic hernia is a birth defect where there is a hole in the diaphragm (the large muscle that separates the chest from the abdomen). Organs in the abdomen (such as intestines, stomach, and liver) can move through the hole in the diaphragm and upwards into a baby's chest.  An epigastric hernia happens when a weakness in the abdominal muscle allows the tissues of the abdomen to protrude through the muscle ‘winged scapula’ (also scapula alata) is when the muscles of the scapula are too weak or paralyzed, resulting in a limited ability to stabilize the scapula. As a result, the medial border of the scapula protrudes, like wings Pronator teres syndrome is a compression neuropathy of the median nerve at the elbow. Carpal tunnel syndrome (CTS) is a medical condition due to compression of the median nerve as it travels through the wrist at the carpal tunnel. The main symptoms are pain, numbness and tingling in the fingers.  Polio, or poliomyelitis, is a disabling and life-threatening disease caused by the that leads to paralysis. Dermatomyositis is an uncommon inflammatory disease marked by muscle weakness and a distinctive skin rash Rhabdomyolysis is a serious syndrome due to a direct or indirect muscle injury. It results from the death of muscle fibers and release of their contents into the bloodstream. Cardiomyopathy is a disease of the heart muscle that makes it harder for your heart to pump blood to the rest of your body  Sarcopenia is the gradual loss of muscle mass Tendinitis is inflammation or irritation of a tendon — the thick fibrous cords that attach muscle to bone that causes pain and tenderness just outside a joint (shoulders, elbows, wrists, knees and heels) Fibromyalgia is a common and chronic syndrome that causes bodily pain and mental distress  Applications and implications in nursing – Skeletal system: Nursing Assessment Health History: Basic profile & Assessment Data: Pain, Altered Sensations Physical Assessment: Posture, Gait, Bone Integrity, Joint Function, Muscle Strength & Size, Skin & Neurovascular Status Assessment of risk factors Autoimmune disorders Calcium deficiency Degenerative conditions  Falls Hyperuricemia Infection Medications Metabolic disorders Neoplastic disorders Obesity Postmenopausal states Trauma and injury  Diagnostic Evaluation Imaging Procedures X-ray - X-rays often allow us to see major problems with the bones (Fractures, Dislocations, Misalignments & Narrowed joint spaces Computed Tomography (CT) – CT indications are often related to trauma due to accident or fell, to rule out fracture. CT scans can spot Blood clots, Bone fractures & Organ injuries Magnetic Resonance Imaging (MRI) - MRIs are especially useful for spotting sports injuries and musculoskeletal conditions, including: Cartilage loss, Joint inflammation, Nerve compression, Spinal injuries, Torn or detached ligaments, tendons, muscles and cartilage Arthrography - type of imaging test used to look at a joint, such as the shoulder, knee, or hip  Diagnostic Evaluation Nuclear Studies Bone Scan (identify bone cancer, determine whether cancer from another part of the body has spread to the bones) Endoscopic Studies Arthroscopy (procedure for diagnosing and treating joint problems) Other Studies Arthrocentesis (procedure to remove excess fluid through a needle from a joint) Electromyography (EMG - electrical activity produced by skeletal muscles) Biopsy ( identify cancer)  Laboratory Studies – (CBC) – Urinalysis (Calcium) – Blood Chemistry – Serum Calcium – Serum Phosphate – Uric Acid – Serum Creatinine – LDH Lactate Dehydrogenase (tissue damage or disease) – SGOT - serum glutamic-oxaloacetic transaminase for liver function – CPK - Creatine phosphokinase - skeletal muscle.  MUSCULOSKELETAL INJURIES: 1. Reassure the patient. 2. Gently support the site. 3. Check circulation, motor, and sensation before and after splinting. 4. Apply ice pack. 5. Splint and immobilize injured limb. 6. Elevate injured limb. 7. Arrange for transport to appropriate care center.  Fractures: Reduction - Closed reduction is a procedure to set (reduce) a broken bone without cutting the skin open. Fixation - Internal fixation is a surgical procedure used to internally set and stabilize fractured bones. Traction - Skeletal traction is a treatment method for broken bones. It's a system where a combination of pulleys, pins, and weights are used to promote the healing of fractured bones. These are usually in the lower body. Casts & splints - Casts and splints are orthopedic devices that are used to protect and support fractured or injured bones and joints.  Splints and splinting An appliance made of wood, metal, or plaster used for the fixation and protection of an injured part of the body aiming to: Immobilize the injured body part. Prevent further damage to muscles, nerves, or blood vessels caused by broken ends of bones. Prevent a closed fracture from converting into an open fracture. Decrease and control pain.  Guidelines can be applied to any type of fracture, regardless of location: Management of airway, breathing, circulation, disabilities, and patients’ environment (ABCDE). Control hemorrhage. Treatment for shock. Relieve pain (can include opioids). Treat any associated injuries and cover the injured area with sterile dressing. Check distal pulses before and after splinting. Immobilize the fracture using splints. Check pulse, motor, and sensation (PMS). Initiate IV antibiotics, in addition to tetanus prophylaxis. Do not re-place protruding bone or explore the wound nor clamp any vessel at the emergency setting and wait for the  Arthroplasty, also called joint replacement, is surgery to replace a damaged joint with an artificial joint (made of metal, ceramic or plastic) Bone grafting is a surgical procedure that uses transplanted bone to repair and rebuild diseased or damaged bones. Knee prosthesis - knee joint replacement is a surgery to replace a knee joint with a man-made artificial joint. The artificial joint is called a prosthesis. Crutch - a crutch is a stick which someone with an injured foot or leg uses to support them when walking. Cervical collar – it is used to support your neck and spinal cord, and to limit the movement of your neck and head Physiotherapy can help to strengthen the bones, as well as muscles.  Applications & Implications in Nursing - Muscles Nursing assessment: Health history: pain, tenderness, tightness, alteration of sense and muscles movements Physical assessment: posture, gait, movements, reflexes, muscle size, muscle mass and neuro muscular junction. Diagnosis: X – Ray, scan (CT & MRI), Biopsy, Blood Test and EMG Cast: cast holds a broken bone (fracture) in place and prevents the area around it from moving as it heals. Casts also help prevent or decrease muscle contractions and help keep the injured area immobile, especially after surgery, which can also help decrease pain.  Site of IM injections: deltoid, ventro gluteal, dorso gluteal, vastus latralis. Traction is a set of mechanisms for straightening broken bones or relieving pressure on the spine and skeletal system Braces are like a belt used to Reduce muscle tension and low back pain and Improve posture to redistribute weight in the spine A splint is a piece of medical equipment used to keep an injured body part from moving and to protect it from any further damage. Stretching is a form of physical exercise in which a specific muscle or tendon (or muscle group) is deliberately flexed or stretched in order to improve the muscle's felt elasticity and achieve comfortable muscle tone