Flashcards in Ch 8 - Skeletal System Deck (58)
What are the two major divisions of the skeletal system?
Axial and Appendicular
What does the axial skeleton consist of?
80 bones skull, hyoid bone, auditory, vertebral column, sternum and ribs
Lie along the longitudinal axis of the body
What does the appendicular skeleton consist of?
126 bones AND muscles
What are the functions of the skeletal system?
Skull protects the brain from injury and the ribs and vertebra protect viscera, such as the heart and lungs
Allows us to sit, stand, and move by the attachment of muscles to bones
Bone acts as a reservoir for over 99 percent of the calcium in our body.
White and red blood cells are produced by red bone marrow contained within bone.
What are two types of bone tissue?
Cancellous (spongy) bone -Spaces filled with red bone marrow.
What are osteons?
Osteons (Haversian systems) are the fundamental unit.
Each osteon consists of a long, cylindrical tube of concentric layers of bone called lamellae.
Inside the lamellae are lacunae where osteocytes can be found
Central canal is lined with the endosteum and contains blood vessels and nerves.
Canaliculi are smaller canals which run perpendicular to the central canal. They carry blood vessels and nerves to lamellae and lacunae
What are the three types of bone cells and what do they do?
Osteoblasts: immature bone cells, responsible for mineralizing the bone matrix
Osteocytes: mature bone cells
Osteoclasts: tear down bone for remodeling and cause the release of calcium
What is the bone growth process called?
ossification or osteogenesis.
What are the two types of ossification?
What happens in intramembranous ossification?
Bones begin as tough, fibrous membranes that are replaced by a bone matrix that is produced by osteoblasts.
Matrix is made up of calcium, phosphate, collagen fibers, and water.
Collagen fibers give bone its flexibility and the minerals give bone its strength.
Other factors essential to bone growth
Vitamins A for osteoblast stimulation and C for collagen synthesis , growth hormone, insulin, and thyroid hormone.
All bones of the skull but the lower jaw is formed by intramembraneous ossification.
What happens in endochondral ossification?
Bones start out as models made of hyaline cartilage.
Common in long bones such as femur
Osteoblasts form a bone “collar” around the diaphysis and replace the cartilage model.
Ossification centers is the area where ossification first begins is the primary ossification center
Each end or epiphysis are the secondary ossification centers. Some bones such as the vertebrae have more than two
What is the medullary cavity?
It is in the center of long bones and is initially filled with red bone marrow, involved in hematopoiesis - RBC formation.
What is the epiphyseal plate?
Between the epiphysis and diaphysis
Between 18 and 25 years of age, made of hyaline cartilage is replaced by bone, becoming the epiphyseal line and the bone is no longer capable of growing in length
What are osteoclasts?
Cells that tear down bone
Regulated by parathyroid hormone
Bone remodeling is a balance between tearing down and building up bone.
Increased demand for calcium, osteoclastic activity will increase
Decreased demand for calcium, osteoblastic activity will increase
What are flat bones?
Thin and consist of a layer of spongy bone between two layers of compact bone
Sternum, ribs, scapulae, and cranial bones
What are long bones?
Greater in length than width
Mostly compact bone, but their epiphyses are spongy bone
Femur, tibia, fibula, humerus, radius, ulna, and phalanges
What are short bones?
Cuboidal in shape
Spongy bone with just a thin outer layer of compact bone
Carpals and tarsals
What are irregular bones?
Variety of shapes
Vertebrae, coxal, some facial bones, and the calcaneus
What are seasmoid bones?
Resemble sesame seeds
Patella (kneecap) and pisiform
What is diaphysis?
Tubular structure with a thick collar of compact bone surrounding a space called the medullary cavity
In children, this is the location of red bone marrow and is responsible for hematopoiesis
In adults, red bone marrow is replaced by yellow bone marrow
Except for skull, ribs, vertebra, and pelvis
What is epiphysis?
At each end of a long bone
Expanded area consisting of a thin layer of compact bone surrounding more abundant cancellous bone
Covering each epiphysis is articular cartilage of the hyaline cartilage. It is smooth and helps in frictionless movement of joints.
What is periosteum?
Membrane surrounds the diaphysis
Dense fibrous connective tissue
Blood vessels and nerves penetrating it
Responsible for “growing pains” during adolescence
What two main types of bone markings?
Projection- Grow out
Depressions- Indent the bone
What is the rib cage formed of?
Formed by sternum and 12 pairs of ribs
What is the sternum?
Sternum is also called the breastbone
Made up of three bones
From most superior to inferior they are the manubrium, the body, and the xiphoid process
Anteriorly, the clavicles and most of the ribs attach to the sternum
Posteriorly, the ribs articulate with the vertebra
What does the spinal column consist of?
7 cervical vertebrae
What are the 4 major curvatures to the spine?
cervical, thoracic, lumbar and pelvic
What is the cervical vertebrae and what does it consist of?
Located in the neck
1st - called atlas/C1 - helps to turn your head, 2nd is axis/c2
Have 3 foramina - 2 transverse and single vertebral foreman .
Vertebral artery , vein, nerves travel through transvers
Spinal cord travels through foramen
What is the lumbar vertebrae and what does it consist of?
Biggest and sturdiest - support body weight
What are clavicles?
Clavicles or collarbones
Slender in shape and each articulates with the sternum and scapula
What are Scapulae?
Thin, triangular shaped flat bones located on the dorsal surface of the rib cage.
Each scapula joins with the humerus and a clavicle
What is the humerus?
Upper part of the arm
Proximally it articulates with the scapula and distally with the radius and the ulna
Head of the humerus articulates with the glenoid fossa of the scapula.
Shoulders can become dislocated because the fossa is very shallow
What is the radius?
Radius is the lateral bone of the forearm
In anatomical position, it is on the same side of the arm as the thumb
Proximally it joins with the humerus and the ulna
Distally with the carpal bones
What is the ulna?
Ulna is the medial bone of the lower arm
Proximal end of the ulna joins with the humerus to form the elbow joint
Distally it also joins with the radius and some of the carpal bones of the wrist
What bones make up the hand?
8 carpal bones make up the wrist
5 metacarpal bones make up the palm
14 phalanges- 3 for each finger and 2 per thumb
What is the pelvic girdle and what does it consist of?
Consists of the coxal (hip) bones and the lower extremities
What are coxal bones?
Coxal bones attach the legs to the axial skeleton and help protect the pelvic organs
Three parts: the ilium (when you put your hands at the hip), the ischium (what you sit on ), and the pubis
Two pubic bones form the front of the coxal bone and come together at the pubic symphysis = a fibrocartilagious joint.
The joint become more lax when you give birth
What is the femur?
Femur is the thigh bone , longest and heaviest in the body
Proximal end joins with the hipbone at the hip socket or acetabulum.
Distal end of the femur attaches to the tibia (shinbone) and the patella or kneecap
What is the tibia and Fibula?
Tibia is the medial bone
Proximal end joins with the femur and fibula.
Distal end attaches to the ankle bones.
Fibula is the thinner, lateral bone
What are joints and what are they classified as?
Junctions or articulations between bones
Based on their structure, joints can be classified as fibrous, cartilaginous, or synovial
What are fibrous joints?
Connected together with short connective tissue fibers abundant with collagen that do not allow much, if any, movement
Between cranial bones (called sutures) and facial bones
What are cartilaginous joints?
Connected together by a disc of cartilage and are slightly movable
What are Synovial joints?
Most numerous type and most movable
Covered with hyaline cartilage
Surrounded by a fibrous joint capsule
Lined with a synovial membrane which secretes a slippery fluid called synovial fluid, acts as a lubricant
Elbows, knees, shoulders, and knuckles
What are Diagnosis of fractures ?
Based on the clinical presentation and confirmed by x-rays
Computerized tomography scans and magnetic resonance imagining are used to more clearly assess the damaged area
What are the healing steps of a fracture?
1. Hematoma forms at the site of the fracture.
2. Fibrocartilaginous callus forms.
3. Bony callus forms.
4. Remodeling occurs when dead cells are removed and new bone cells are laid down.
What is Osteoarthritis (OA)
"wear and tear"
Affects the weight-bearing joints of the hips and knees
Cartilage between the bones and the bones themselves begin to break down
Occurs in elderly individuals due to the aging process
Joint stiffness, aching, and pain
Anti-inflammatory drugs, intra-articular steroid injections, transplanting harvested cartilage cells, surgical scraping of the joint, joint replacement
What is Rheumatoid Arthritis (RA)
Chronic systemic disease
Autoimmune component (everyone)
Synovial membrane is destroyed causing edema and congestion.
Scar tissue forms, bones atrophy, and visible deformities become apparent.
Moderate to severe pain in the affected joints
Anti-inflammatory drugs, heat or cold treatments, cortisone injections, immunosuppressive drugs, low-impact aerobic exercise and warm water exercises
What is Gout (Gouty Arthritis )
Type of arthritis associated with high uric acid levels in the blood
Crystalline deposits in the joints, kidneys, and various soft tissues
Acute or chronic joint pain, commonly in the great toe
Pain medications, anti- inflammatory drugs, and dietary modifications
What is Bursitis?
Inflammation of a bursa, the fluid-filled sac that cushions tendons
Elbow, knee, shoulder, and hip
Overuse and trauma to joints
Joint pain, swelling, and tenderness in the structures surrounding the joint
Rest, pain medications, steroid injections, aspiration of excess fluid from the bursa, and antibiotics if caused by infection
What is carpal tunnel?
Occurs when the median nerve in the wrist is excessively compressed by an inflamed tendon
Overuse of the wrist
Weakness, numbness, pain, or a tingling sensation in the hand, wrist, or elbow
Wrist splints, pain medications, steroid injections, surgery to reduce the pressure on the affected nerves
What is Kyphosis?
Abnormally exaggerated curvature of the spine
Growth retardation or improper development of the epiphyses as a result of rapid growth
No symptoms may occur, may be mild pain, tiredness, or tenderness or stiffness of the thoracic spine.
Exercise, a firm mattress, and a back brace
Degenerative disc disease
Pain, back weakness, and fatigue
Spinal fusion or grafting, Harrington rods may also be surgically inserted
What is Lordosis?
Exaggerated inward (convex) curvature of the lumbar spine
Obesity, tuberculosis of the spine, poor posture, pregnancy, osteoporosis, and continual wearing of high heels
Mild to moderate pain
Preventing or treating the underlying cause
What is Scoliosis?
Abnormal, S-shaped lateral curvature of the thoracic or lumbar spine
Develop prenatally when vertebrae do not fuse together or result from diseases that cause weakness of the muscles that hold vertebrae together
Back braces, surgery to correct spinal curves, and physical therapy to strengthen the spine
What is Osteogenesis Imperfecta?
Decreased amounts of collagen in their bones
Disorder is hereditary
Fractures, blue sclera, dental problems, hearing loss, a triangular face, abnormal spinal curves, very small stature, a small chest or barrel shaped chest, loose joint, and small muscles
List of treatments is extensive
What is Osteoporosis?
Bones become more porous over time and a decrease in bone density is the result.
Hormone deficiencies, a sedentary lifestyle, a lack of calcium and vitamin D in the diet, bone cancers, corticosteroid excess, smoking, excess alcohol consumption, and the use of steroids
pain management medication
What is Osteosarcoma?
Bone cancer that originates from osteoblasts
Cause is unclear
Pain and swelling of the soft tissue around affected bones
Surgery, chemotherapy, and radiation therapy
Amputation of the affected limb and fitting of prosthesis may be necessary to prevent metastasis
What is Paget’s Disease?
Bones become enlarged, deformed and weak.
May be caused by a childhood viral infection and may have some genetic basis
Bone pain, deformed bones, and fractures
Surgery to remodel bones, hip replacements, medications to prevent bone weakening, and physical therapy