Chapter 9: Mechanisms and Characteristics of Sports Trauma Flashcards
How are load and stress related?
A load is an external force acting on tissue, whereas stress is an internal resistance to an external load.
What is mechanical failure & how is it related to yield point?
Mechanical failure occurs when the ability of the tissue to withstand stress and strain is exceeded. Yield point is when tissue is deformed to the extent that it no longer reacts elasticity
What are the 5 types of tissue stresses?
Compression: external load on opposite surfaces in opposite directions
Tension: force that pulls or stretches tissue, Muscle strains & Ligament sprains
Shearing: equal but not opposite loads are applied to a surfaces in parallel directions, blisters, abrasions, vertebral disk injuries
Bending: two force pairs act at opposite ends of a structure
Torsion: twisting in opposite directions from opposite ends causing a shear stress
What is clonic? Tonic?
Clonic is an involuntary muscle contraction with alternate contraction and relaxation in rapid succession. Tonic is a muscle contraction that lasts for a period of time
When does DOMS appear, is most intense, and is symptom free?
About 12 hours after injury, most intense after 24-48 hours, and is symptom free after 3-4 days
What are osteoclasts?
Bone-remodeling cells
What are osteoblasts?
Bone-producing cells
Pott’s Fracture
Bimalleolar ankle fractures
Colles Fracture
Distal radius fracture with dorsal displacement of the wrist and hand
Saltar Harris Classification
Epiphyseal growth plate injury classifications…Type 1: complete separation, Type 2: fracture/separation of growth plate, Type 3: fracture physis, Type 4: fracture-physis and metaphysis Type V: crushing with no discplacement
Neuropraxia
Interruption in the conduction of the impulse down the nerve fiber, mildest form, compression or mild blunt blows close to the nerve, temporary loss of function
Neuritis
A chronic nerve problem, inflammation of the nerve, minor nerve problems to paralysis, crushing or severing of the nerve
Nerve injury via what 2 forces?
Compression and overstretching
5 types of open wound
abrasions, incisions, lacerations, punctures, avulsions
What are the 3 types of muscles
smooth, cardiac, and striated
What is muscle guarding?
muscle contraction in response to pain
What are the 3 grades of strain?
1: some muscle fibers have been stretched or actually torn
2: a number of muscle fibers have been torn, and active contraction of the muscle is extremely painful
3. a complete rupture of a muscle has occurred in the area of the muscle belly at the point at which muscle becomes tendon or at the tendinous attachment to the bone
tendon injuries
can produce and maintain a pull from 8700 to 18000 pounds per square inch. a breaking point occurs after a 6% to 8% increase in length.
What differentiates a trigger point from a tender point?
trigger point: referred pain
tender point: pain at the site of palpation
What does ectopic mean?
located somewhere besides the normal place
What is myositis ossificans?
calcium deposits that result from repeated trauma
What is the difference between hyaline, fibrous, and elastic cartilage?
hyaline: lining of bones in joints (most abundant)
fibrous: tough support or great tensile strength
elastic: line ears and several tubes
What is a ball-and-socket joint? Examples?
allows widest ROM
shoulder and hip
What is the difference between synarthrotic, amphiarthrotic, and diarthrotic joints?
syn: immovable joint
amp: slightly movable joint
dia: freely movable joint
What is a hinge joint? Examples?
allows only flexion and extension
elbow and knee
What is a pivot joint? Examples?
allows rotation
axis and atlas
What is an ellopsoidal joint? Example?
allows angular motion but not rotation
b.t. metacarpals and phalanges
What is a saddle joint? Example?
both concave and convex surface. wide ROM
ONLY thumb
What is a gliding joint? Example?
allows sliding or twisting without any circular motion
carpals and tarsals
What is the difference between a subluxation and a dislocation?
subluxation: a bone is forced out of alignment but goes back into place
dislocation: a bone is forced out of alignment and stays out util surgically or manually replaced or reduced
How is a first-time dislocation treated differently than successive ones? How does the pain level compare?
“once a dislocation, always a dislocation”. connective tissue is too loose and joint is extremely vulnerable to subsequent dislocations.
first-time should always be considered and treated as a possible fracture. pain decreases over time.
What is osteoarthritis? What is arthoplasty?
osteoarthritis: a wearing down a hyaline cartilage
arthoplasty: surgical repair of joint
What are the 5 functions of bone?
body support, organ protection, movement, calcium storage, and formation of blood cells
Where do you find flat bones?
skull, ribs, and scapulae
Where do you find irregular bones?
vertebral column and the skull
Where do you find shot bones?
wrist and ankle
Where do you find long bones?
humerus, ulna, femur, tibia, fibular, phalanges
What is spongy and compact bone?
Spongy: aka cancellous bone (inside and ends of bone)
Compact: aka cortical bone (outside of bones)
What is the medullar cavity?
a hollow tube in the long bone diaphysis, contains a yellow, fatty marro in adults. lined by the endosteum.
What is the periosteum?
a dense, white, fibrous membrane that covers long bones except at joint surfaces. many fibers, called sharpey’s fibers, emante from the periosteum and penetrate the underlying bone. it is interlaced with muscle tendons. on its inner layer there exists countless blood vessels and osetoblasts.
What lies between the diaphysis and the epiphysis?
the growth plate. ossification in long bones begins in the diaphysis and in both epiphyses. it proceeds from the diaphysis toward each epiphysis and from each epiphysis toward the diaphysis.
Why is the clavicle considered to have an anatomical weak point?
prone to fractures because it changes from round to flat at the same point at which it changes direction
What is a greenstick fracture?
incomplete breaks in bones that have no completely ossified
What is a comminuted fracture?
consists of three or more fragments at the fracture site - caused by a hard blow or a fall in an awkward position.
What is a linear fracture?
bone splits along its length - from jumping from a height and landing in such a way as to impart force or stress to the long axis
What is a transverse fracture?
occur in a straight line, more or less at right angles to the bone shaft - caused by a direct blow
What is an oblique fracture?
when one end of the bone receives sudden torsion or twisting while the other end is fixed
What is a spiral fracture?
an S-shaped separation - common in football and skiing, where the foot is firmly planted when the body is suddenlyAA rotated in an opposing direction
What is an impacted fracture?
causes a long bone to receive, directly on its long axis, a force of such magnitude that the osseous tissue is compressed - result from a fall from a height.
What is an avulsion fracture?
separation of a bone fragment from its cortex at an attachment of a ligament or tendon - occurs as a result of a sudden, powerful twist or stretch of a body part
What is a blowout fracture?
occur to the wall of the eye orbit as a result of a blow to the eye
What is a serrated fracture?
when two bony fragments have a sawtooth, sharp-edged fracture line - caused by a direct blow
What is a depressed fracture?
most often in flat bones - caused by falling and striking the head on a hard, immovable surface or by being hit with a hard object
What is a contrecoup fracture?
occur on the side opposite the point at which trauma was initiated
common sites of stress fractures?
tibia, fibula, metatarsal shaft, calcaneus, femur, pars interartcularis of the lumbar vertebrae, ribs, and humerus
