Lecture 4: Skeletal System Flashcards
How many bones are in the adult human body?
206
What are the two types of tissues of the skeletal system?
Bone and Cartilage
What are the two types of bones?
Compact (outer layer) and Concellous (spongy, inner layer)
What are the two types of bone cells?
Osteoclasts and osteoblasts
What are osteoclasts?
Cells that dissolve old, damaged bone tissue so it can be replaced with new, healthier cells
What are osteoblasts?
Cells that form new bones and growth to existing bone tissue
What are the functions of the skeletal system?
- provides structural support and protection for internal organs
- stores minerals such as calcium and phosphorus
- produces blood cells in the bone marrow
What are some congenital and hereditary disorders of the skeletal system?
- spina bifida
- osteopetrosis
- osteogenesis imoerfecta
- achondroplasia
- congenital hip dysplasia
What is spina bifida?
A congenital condition where the spinal column doesn’t close completely during fetal development
What are the 3 types of spina bifida?
- Occulta
- Meningocele
- Meningomyelocele (open spina bifida)
What is spina bifida occulta?
The mildest form of spina bifida, which results in a small gap in the vertebra without a visible sac
What is spina bifida with meningocele?
When a sac of CSF protrudes through the spin cord opening, but the spinal cord remains unaffected
What is spina bifida with miningomyelocele?
The most severe form of spina bifida when a sac of CSF, the spinal cord and meninges protrude through an opening in the spine
What is osteopetrosis?
A rare hereditary bone dysplasia in which defective osteoclasts prevent the resorptive mechanism of bones making them very dense
What is another name of osteopetrosis?
Marble bone since the bones are highly calcified
What is osteogenesis imperfecta?
A hereditary disorder of connective tissue that results in multiple bone fractures and blue color of the sclera of the eyes
What is another name for osteogenesis imperfecta?
Brittle bone disease
What is achondroplasia?
The most common form of dwarfism that results from impaired cartliage development
What is achondroplasia characterized by?
Short limps with a normal acial skeleton
What is congenital hip dysplasia/dislocation?
Incomplete formation of the acetabulum which leads to hip dislocation
What are inflammatory/infectious disorders of the skeletal system?
- Rheumatoid arthritis
- Osteomyelitis
- Bursitis
- Rotator cuff tears/meniscus tears
What is rheumatoid arthritis?
A chronic inflammatory disease affecting the small joints
What are the RA variants?
- Ankylosing spondylitis
- Reactive arthritis
- Psoriatic arthritis
What is ankylosing spondylitis?
A type of RA that primarily affects the spine, causing the joints between the vertebra and SI joints to be inflammed
What is ankylosing spondylitis also known as?
Bamboo spine
What is reactive arthritis?
A type of inflammatory arthritis that develops as a reaction to an infection elsewhere in the body
What are the causes of Reactive arthritis?
Chlamydia and STI’s
What are the sumptoms of Reactive arthritis?
Joint pain and swelling, typically 2-6 weeks after the initial STI infection
What is reactive arthritis also known as?
Reiters syndrome
What is psoriatic arthritis?
A chronic inflammatory condition that affects the joints and the skin
What is Osteomyelitis?
Bone infection caused by bacteria that commonly affects the long bones
What are the two types of osteomyelitis?
- Bacterial osteomyelitis
- Tuberculous osteomyelitis
What is bacterial osteomyelitis?
Inflammation of the bone and marrow casued by infectious organisms, typically staph infections
What is tuberculous osteomyelitis?
Bone infections of the T and L spine also known as Pott’s disease
What is bursitis?
Inflammation of the small fluid sacs located near the joints that reduce the friction caused by movement
What is bursitis usually caused by?
Repeated physical activity, trauma, rheumatoid arthritis, gout or infections
What are rotator cuff tears?
A tear in the musculotendinous structure of the shoulder
What is the modality of choice to diagnose bursitis?
MRI
What are metabolic bone diseases?
- osteoporosis
- osteomalacia/rickets
- gout
- paget’s disease
What is osteporosis?
Decreaed bone mass that causes the bone to become porous and break easily
What are the causes of osteoporosis?
Aging and postmenopausal hormonal changes
How should kVp be altered when imaging osteoporosis?
A lower kVp
What is osteomalacia?
Insufficient mineralization of the adult skeleton that causes softening of the bone and bowing
What is osteomalacia caused by?
An inadequate intake or absorption of calcium
What is rickets?
The childhood form of osteomylacia that causes the softening of bones due to vitamin deficiency
What are the 3 classifications of rickets?
- bowing in the thighs
- bowing in the knees
- knock knees
How are osteomalacia and rickets treated?
Through vitamin D therapy
What is gout?
A disorder in the metabolism of purine which increases the uric acid in the blood and leads to deposits of uric acid crystals on the joints
How does gout manifest?
As painful arthritis that attacks a single joint, 1st MSP joint
What is paget disease?
An abnormal bone remodeling also known as osteitis deformans
What is an associated risk of paget’s disease?
Osteosarcoma later in life
What are the symptoms of paget’s disease?
Bone pain, bone deformities, fractures, joint pain and hearing loss
What are types of bone tumors?
- benign tumors
- malignant tumors
- bone metastases
What are types of benign bone tumors?
- Osteochondroma
- Enchondroma
- Giant cell tumor (osteclastoma)
- Osteoma
What is osteochondroma also known as?
Exostosis
What is Osteochondrom/Exostosis?
A benign projection of bone with a cartilagenous cap that arises in childhood
Where do osteochondroma/exostosis normally appear?
Near the knee
What are characteristics of osteochondroma?
- Long axis of the tumor runs parallel to the bone shaft
- points away from the nearest joint
What is Enchondroma?
A low growing benign cartilaginous tumor that arises in the medullary canal
Where does Enchondroma usually present?
in small bones of the hands and feet
How are enchondroma found?
When imaging fractures that occur with minimal force
What are giant cell tumors (osteoclastoma)?
Tumors that arise athe ent end of the distal femur or proximal tibia of young adults
What is osteoma?
Tumors that arise in the outer table of the skull, paranasal sinus and the madible that are painful
What are types of malignant bone tumors?
- Osteosarcoma
- Chondrosarcoma
- Ewing’s sarcoma
- Multiple myeloma
What is osteogenic sarcoma (osteosarcoma)?
A malignant tumor of osteoblasts that generally appear at the end of long bones in the metaphysis
What group of people do osteogenic sarcomas appear in?
Most common in people between the age of 10-25
What is Chrondrosarcoma?
A malignant tumor that originates from a pre-existing cartilaginous lesion (osteochondroma or enchondroma)
Where do chondrosarcoma typically originate?
In ribs, scapula or vertebra
When do chondrosarcoma develop?
Later in age and grow slowly/metastasize later
What is Ewing sarcoma?
A type of cancer that begins as a growth of cells in the bone and soft tissue around the bone
What is multiple myeloma?
A widespread malignancy of the plasma cells
What are multiple myeloma associated with?
Bone destruction, bone marrow failure, hypercalcemia, renal failure and recurrent infections
What group of people do multiple myeloma affect?
Persons between 40-70
What is bone metastases?
The most common malignant bone tumorH
How do bone metastases spread?
From primary tumors by means of the bloodstream or lymphatic vessels
What are typical sites of metastic spread?
Bones containing red bone marrow, spine, pelvis, ribs, skull and upper ends of humerus/femur
What are complete fractures?
Fracture that results in two bone fragments
What are incomplete fractures?
Fracture where one side is broken but the cortex is intact
What is an open fracture?
Compound fracture where there is an associated skin wound
What is a closed fracture?
Fracture with the skin intact
What are the types of bone fractures?
- Transverse
- Oblique
- Spinral
- Communinuted
- Greenstick
- Stress
What is a transverse fracture?
Fracture line that is horizontal to the long axis of a bone
What is an Oblique fracture?
A fracture line that extends at an angle to the long axis of a bone
What is spiral fracture?
Fracture line that encircles the shaft of a bone
What is a communinuted fracture?
More than two bone fragments
What is a greenstick fracture?
Occurs in immature bone where one side of cortex remains intact
What is a stress fracture?
Response of bone to repeated streessors none of which alone would cause a fracture, but combined will
What are common fractures?
- Colles’ (wrist)
- Boxer’s (hand)
- Jones (foot)
- Monteggia (forearm)
- Galeazzi (radius/ulna)
What is a Colles fracture?
A transverse fracture through the distal radius (wrist)
What is a Boxer’s fracture?
Transverse fracture of the neck of the 5th metacarpal oftne caused by hittin an object with a closed fist
What is a Monteggia fracture?
Fracture in the ulnar shaft (forearm) associated with anterior dislocation of the radius at the elbow
What is Galeazzi fracture?
A fracture of the radial shaft and rosal disloation of the ulna at the wrist
What is a Jones fracture?
Transverse fracture of the 5th metatarsal bone (foot)
What are the two classifications of spinal fractures?
Stable and unstable
What is a stable spine fracture?
Where one of the two major columns of the spine are intact
What is an unstable spine fracture?
Both major columns of the spine are disrupted
What are the types of spinal fractures?
- Jefferson
- Hangman’s
- Odontoid
- Clay Shovler’s
What is a Jefferson fracture?
Communited fracture of C1
What is an Odontoid fracture?
Fracture at the base of the dens
What is a Hangman’s fracture?
Fracture of C2 arch with sublucation of C2-C3
What is a clay shoveler’s fracture?
An avulsion fracture of a spinous process in the lower C spine or upper T spine
What is an avulsion fracture?
Where small fragments of are pulled away from bone by attached ligaments
What is spondylosis?
A cleft in the pars interarticulars of the vertebra without displacement that is very painful and can lead to small stress fractures or cracks
What site is spondylosis most common?
At L5
