Week 8 - Bones, Falls, and Fractures Flashcards
What are the 2 types of bone tissue in our body?
- Spongy (trabecular or cancellous) bone
- Compact (cortical) bone
What are the characteristics of spongy bone?
- Porous and contains red marrow
- Weaker and easier to fracture than cortical bone
Where are the blood cells made?
Red bone marrow in spongy bone
What are the factors affecting bone strength?
1) Bone density
2) Bone Quality
3) Bone geometry (morphology)
What is bone density?
Mass of bone per unit of volume
Q: What percentage of bone resistance to fracture is due to bone density?
50-80%
What is the estimated rate of bone loss after menopause for the first 10 years?
1 or 2% per year for the first 10 years.
What is the estimated rate of bone loss after menopause after the first 10 years?
A decrease of 0.3 to 0.5% per year
Is the loss of bone density after menopause in women a central effect?
Yes, because it is a hormonal issue so it affects every bone in the body
Which connective tissue connects and supports the whole body?
Collagen
Which disease results in a defect of an insufficient collagen or abnormal collagen?
Osteogenesis Imperfecta (genetic condition)
What characterizes bone quality?
The structural material from which bone is constructed
What are the 2 major components that increases the structural integrity of bone?
- minerals
- collagen
What are the major minerals in bone, in order of quantity?
- calcium
- magnesium
- sodium
- potassium
What is the role of minerals in bone?
provide rigidity and strength
What happens to collagen and mineral tissues in our bone with aging?
They become less resistant to mechanical loading (i.e. pressure applied on bones)
What is bone geometry?
As we age, the diameter of our bones changes and this affects our bone’s strength
For the same bone thickness, the bone with the greater diameter is…
more solid vs small diameter
In OA, what process compensates the loss of bone mass density (BMD)?
Periosteal apposition
What is periosteal apposition?
The addition of tissue along the outer surface of the bone
Other than density of bone, what affects the strength of a bone?
Geometry and integrity of the bone’s framework
Does training affect density, geometry and integrity of the bone’s framework?
Yes
What allows your bones to be lightweight and strong? And how do they do that?
Bone fibers. They crisscross each other in layers which allows them to align precisely in order to carry the forces of tension and compression.
What is osteopenia?
A condition characterized by lower than normal bone density. It may be a precursor for osteoporosis.
What is osteoporosis?
A disease where bone mass and structure decline to a point where there is a significant increase in fragility and susceptibility to fracture
What is established osteoporosis?
Preferred term for those with osteoporosis and having one or more fragility fractures
What is the standard deviation threshold for osteopenia?
-1 to -2.5 s.d. below to average
What is the standard deviation threshold for osteoporosis?
A s.d. of -2.5 or lower than the mean value
What is a fragility fracture?
Any fall from standing height or less, that results in a fracture
Why is it called fragility fracture?
Because the body should be able to sustain a fall from this height (standing height) without a fracture unless there is an underlying cause that makes the bones fragile
What are the most common areas for fragility fractures?
Hip, spine and wrist
True or false, OA suffering hip fractures often experience a loss of independence.
True
What is the ratio/percentage of OA who fracture their hips and recover sufficiently to perform basic and instrumental ADLs?
Less than 1/3
What are the chances of women sustaining a fracture during their lifetime?
40%
Should OA with osteoporosis reduce physical activity to prevent fractures?
No!
What is kyphosis?
Change in posture with osteoporosis —their back curves.
What are the 7 principles for maximizing the influence of exercise on bone?
- Dynamic rather than static mechanical stimulation
- Stimulus must be at a suprathreshold level
- Improved by brief but intermittent exercise
- A pattern that differs from the usual loading pattern
- The response that any bone has to a mechanical stimulus such as exercise is proportional to the loading cycle (how frequently the stimulus is applied)
- Sufficient energy to rebuild itself
- Abundance of calcium and vitamin D availability
What acts as the message that tells bone to grow in response to mechanical loading?
Most likely fluid flow through the canalicular channels and around the bone trabeculae.
What amplifies hormonal responses promoting bone growth?
They are amplified by intensity and by differences in exercise patterning.
What is a synonym of bone growth?
Osteogenesis
Which has a greater effect on bone density, high-intensity resistance training or high impact aerobic training?
High-intensity resistance training
What is the effect/advantage of resistance training?
It is site specific and the intensity needed is only above 75% of 10 repetition-maximum
True or false: dividing the total volume of work performed/week across 5 days has a greater osteogenic effect than doing the same volume of work in fewer days.
True
Do short intense exercise bouts build bone more effectively than longer sessions do?
Yes.
What should we do if we want to reduce the exercise time?
It is better to shorten each exercise session than to reduce the number of sessions performed
What is the stimulus for tissue change?
It is caused by an overload.
How do we create an overload?
When tissue adapts when faced with a challenge that is beyond those encountered in everyday life.
What are the implications of resistance training programming? Which aspects are important to vary?
- amount of resistance
- method used to provide resistance
- directions in which the force is applied
What is “The Book Drill”?
A test/exercise in which an OA has to move books from one corner to another.
What is the goal of “The Book Drill”?
Balance training (in ADL situation)
What are the contractions used in “The Book Drill”?
Dynamic (concentric, for getting up, and eccentric for going down)
What are the different variations for “The Book Drill”?
Directions in which the force is applied (forward, backward, sideways).
You can also increase resistance by using a weighted vest, changing the distance of the corners, or using heavier books.
What are the goals, contractions and variations of the “Ladder Drills”?
Goal: Agility training
Contractions: Dynamic (concentric and eccentric)
Variations: Intensity (walking vs jumping, patterns of movements)
Is there a limit in the number of repetitions?
Yes
What is the number of loading cycles that have a positive effect on bone density?
40 cycles per day
What is needed for the development of new bone?
Metabolic process requiring energy
What are the 2 major dietary problems that OA may face?
- low energy intake (esp. low protein intake)
- low calcium intake
What is the role of calcium in bone? Name 2 other minerals that play a role in bone.
Major raw mineral used to build bone.
Phosphate and magnesium.
These mineral need to be delivered from the digestive system to the building sites in the bones.
What is the role of vitamin D?
Facilitates the absorption of calcium, phosphate and magnesium ions through the intestinal wall and into the bloodstream.
What are the 4 ACSM Guidelines for preserving bone health in adulthood and what do they consist of?
-
MODE:
-weight-bearing endurance activities (tennis; stair climbing, jogging),
-activities that involve jumping (volleyball)
-resistance exercise (weight lifting) - INTENSITY: moderate to high
- FREQUENCY: weight-bearing endurance activities 3-5x/week and resistance exercise 2-3x/week
- DURATION: 30-60min/day of a combination of weight-bearing endurance activities, activities that involve jumping and resistance exercises that target all major muscle groups
What are the ACSM guidelines for ELDERLY WOMEN AND MEN WITH DIAGNOSED OSTEOPOROSIS?
- 1-3 sets with 5-8 rep of 4-6 weight-bearing, upper- and lower- body strength exercises using body weight as resistance
- Activities performed 2-3 days/week
- Additional resistance may be applied gradually and conservatively (up to 10 lbs) with weighted vest
- Therabands and rubber tubing can be used to facilitate range-of-motion exercises
What are the ACSM guidelines for ELDERLY WOMEN AND MEN WITH DIAGNOSED OSTEOPOROSIS? Specifically, what should be avoided?
- Avoid impact exercise, spinal flexion against resistance, spinal extension, high compressive forces on the spine, quick truck rotation
Are compression fractures likely to cause nerve or spinal cord damage in OA with osteoporosis?
No, most damages are limited to the front of the vertebral column.
What is the leading cause of injuries among Canadian 65+?
Falls
What is the percentage of Canadians 65+ who experience one fall each year?
20-30%
What are the consequences of falls?
- causes 95% of hip fractures
- leading to death in 20% of cases
- accounts for 85% of seniors’ injury-related hospitalizations
- causes over 1/3 of admissions to long-term care facilities after being released from the hospital
Where do about half of the falls that lead to hospitalization in OA occur at home?
Bathrooms and stairs
What is the vicious cycle of falling?
Fall –> fear of falling –> reduced physical activity –> loss of muscle mass and strength (increases risk of falls) -> fall
How do you break the vicious cycle of falls?
Fall –> fear of falling –> more cautious about movement at home but still moves around –> lives at home and takes care of house (decrease risk of falling)
True of False: OA may make more errors when they are required to move faster than their ability to move accurately?
True
What are the continuous and progressive decrease in age-related changes in sensory and motor function?
- Nerve conduction velocity (decreases by 10-15%)
- Proprioception at the foot and ankle (decrease response from muscle spindles)
- Vestibular function (dizziness)
Which factors affect the incidence of falls in OA?
- Impaired position sense: orientation of the body in space + position of body parts relative to each other
- Foot position awareness: footwear with low heels and thin, hard soles maximizes proprioception
What are age-related changes in vision?
- visual acuity decreases with age
- loss of vision due to anatomical changes in visual system (cornea, lens, iris, vitreous humor, visual cortex)
- vision loss:
-peripheral vision
-glare sensitivity
-dark adaptation
-depth perception
Do seniors have difficulty driving at night?
Yes
Rods or cones for night vision?
Rods
What are age-related changes in hearing?
Decline in
- acuity
- localization of sound
- ability to mask extraneous sound
What is one of the frequent complain of OA related to hearing?
They hear someone speak but are not able to make sense of the words.
True or false: hearing impairment can be complicated by tinnitus (ringing in the ears), speaking too fast.
True
What are functional implications of vision and hearing impairments?
- exercise area should be well-lighted to compensate for vision impairment of OA (unless the main goal is to force them to use senses other than vision)
- instructions should be spoken clearly and slowly
- instructor should face participants and observe their comprehension
- for participants with a history of frequent falls or postural instability, an external support (e.g., chair, wall bars, walker, etc.) can be useful for safety and confidence
