Block 12 Block 12 Week 3 Flashcards
Falls and Fractures in Elderly People
Fall: = an unexpected event in which the participant comes to rest on the ground/floor
Fragility Fracture: fracture from a fall from standing height or less (commonly affects wrists, spine,
pelvis, humerus and femur
Epidemiology of falls
- Due to an ageing population, falls are an increasing problem.
- 5-10% result in serious injury or
fracture, and up to 60% of people who fall sustain some sort of injury. - Falls reduce quality of life, and
are costly in terms of health and social care provision - 40% of nursing home admissions are due to falls
- 30% of over 65s living in the community fall each year, and 50% of 80 year olds fall at least once a
year. - Incidence rates of falls in nursing homes or hospitals is 2-3x higher
Costs of falls
- The annual cost of fractures in the UK is over £4 billion
- Hip fractures account for £2 billion of this
Other consequences of falling
- fear of falling
-reduced physical activity
- functional decline
-impaired activities of daily living
- social isolation
- depression
- an increased risk of falls
-fractures
- if you are on the floor for a long time then possible dehydration, hypothermia, pressure sores, and
pneumonia
What is the leading cause of mortality in over 75s in the UK?
- Falls
Causes of falls
- Environment: poor lighting, rugs, footwear/clothing
- Pathology: parkinsons disease, incontinence, arthritis,
- Drugs: polypharamacy, psychotropics
- Physiology: slowed reflexes, muscle weakness, stiff joints
Important risk factors for falling in elderly patients
- Low bone mineral density
- Age (every 5 year increase in age doubles the risk)
- Female gender
- Low body weight
- Family history of hip fracture
- Prior history of fractures or falls
- Smoking
- Ethnicity (Afro-Carribeans have very low fracture risk, while Caucasians have a higher risk)
- Corticosteroid use
- Gait deficit
- Balance deficit
- Visual deficit
- Cognitive impairment
- Hypotension
- Epilepsy
- Dementia
- Peripheral neuropathy
List the strengths and weaknesses of study designs used to identify risk factors
for falling ?
Many of the studies that look at risk factors for falling are observational or from surveys, which are
unable to identify cause and effect of the variables they’re studying (e.g. asking people how many
falls they’ve had - recall bias, especially in older people)
- Cross-sectional studies are an example of a survey, which aren’t good as they are only looking at one
point in time, making it hard to establish a cause - A case-control study would compare one group with a risk factor for falling to another group without
the risk factor, and these studies are limited by confounding variables and bias - A better study design would be a prospective cohort study, which follows participants and looks at
their baseline characteristics, and then follows them for falls outcomes and associations - Other difficulties encountered in falls research is that well conducted RCTs are needed to provide the
best evidence, but these studies are often highly selective in their populations and settings. Also,
different researchers can have different definitions of what a fall is - Falls research needs to have a long enough follow up to allow sufficient events to occur (12 months is
good), and studies are often not long enough as falls are relatively rare events - Other aspects that can affect falls research is that there can be losses from groups due to illness/
death (due to age), people may not want to comply with the study, people may not admit they’ve had
a fall, and blinding is often impossible causing performance bias
List interventions shown to be effective in preventing falls and fractures
- With hip fractures, fall prevention can help to prevent minor injuries and fractures, but can’t get rid of
all falls. This includes a falls risk assessment, assessing a person’s gait, balance, mobility, muscle
weakness, osteoporosis risk, fear of falling, visual and cognitive impairment, incontinence, home
hazards etc - Falls prevention can also include education for the patient, identification of any medical conditions, a
medication review (and taking patients off of psychotropics), strength and balance training, sensory
evaluation, and any assistive devices - Interventions that have been shown to have no/little effect on falls include brisk walking, being in
residential care (falls increase), doing high intensity strength training (increases injury), and education
and behavioural modifications alone - Surgery for hip fractures should be performed very quickly, with sufficient analgesia, and post-op
physiotherapy and mobilisation should be done
Medications which can protect the bone include
- Bisphosphonates = used for osteoporosis, and reduce hip fractures by 30%, but daily use is
associated with poor compliance and gastric problems - Vitamin D and calcium supplements = 10-15% reduction in hip fracture rate, but vitamin D
alone has no beneficial effect on fracture incidence - HRT = used in post-menopausal women to reduce fractures by 20-30%, but can increase
breast and ovarian cancer risk, as well as cardiovascular disease risk - Teriparatide (PTH) = daily injections for up to 18 months reduces fractures by increasing
osteoblast activity
Outline the approaches to health promotion for falls and osteoporotic fractures
Health promotion for falls and fracture prevention includes trying to make the environment safer for
older people (e.g. good road networks, safe pavements, good street lighting, well built houses,
accessible public transport etc)
- Screening for older adults is about identifying those most at risk of falls and fractures, and preventing
them before they occur. Older people coming into contact with health professional should be asked
routinely about falls, and older people who report falls should be observed for balance and gait
deficits
HIP JOINT
- Hip Joints main function is for STABILITY AND WEIGHTBEARING
- Both the acetabulum and head of femur are covered in articular cartilage, which is thicker at the places of weight bearing.
HIP JOINT LIGAMENTS
Ligament two types:
INTRACAPSULAR and EXTRACAPSULAR
INTRACAPSULAR:
- ligament of the head of the femur/ ligamentum teres. Remnant of the left umbilical vein of the fetus.
EXTRACAPSULAR:
- Iliofemoral ligament (l looks like number 1 strongest)
- Pubofemoral
- Ischiofemoral (s is for slow so its the weakest)
Iliofemoral Ligament
Iliofemoral ligament – arises from the anterior inferior iliac spine and then bifurcates before inserting into the intertrochanteric line of the femur.
It has a ‘Y’ shaped appearance, and prevents hyperextension of the hip joint. It is the strongest of the three ligaments.
PUBOFEMORAL LIGAMENT
Pubofemoral – spans between the superior pubic rami and the intertrochanteric line of the femur, reinforcing the capsule anteriorly and inferiorly.
It has a triangular shape, and prevents excessive abduction and extension.
ISCHIOFEMORAL LIGAMENT
Ischiofemoral– spans between the body of the ischium and the greater trochanter of the femur, reinforcing the capsule posteriorly.
It has a spiral orientation, and prevents hyperextension and holds the femoral head in the acetabulum.
HIP JOINT RADIOLOGICAL APPERANCE
Blood Supply to the Hip Joint
The arterial supply to the hip joint is largely via the branches of the deep femoral artery:
- medial circumflex femoral arteries (majority of blood supply)
- lateral circumflex femoral arteries (has to penetrate through illiofemoral ligament)
They anastomose at the base of the femoral neck to form a ring, from which smaller arteries arise to supply the hip joint itself.
- Damage to the medial circumflex femoral artery can result in avascular necrosis of the femoral head.
- The artery to head of femur and the superior/inferior gluteal arteries provide some additional supply.
Nervous supply to hip joint
- SCIATIC
- FEMORAL
- OBTURATOR
These same nerves innervate the knee, which explains why pain can be referred to the knee from the hip and vice versa.
NECK OF FEMUR FRACTURE (NOF)
- Blood supply to the neck of the femur is retrograde.
- Passing from distal to proximal along the femoral neck to the femoral head. This is predominantly through the medial circumflex femoral artery
-Consequently, displaced intra-capsular fractures disrupt the blood supply to the femoral head and, therefore, the femoral head will undergo avascular necrosis (even if the hip is fixed).
-Patients with a displaced intra-capsular fracture therefore require joint replacement (arthroplasty), rather than fixation
NECK OF FEMUR FRACTURE
- NOF are also known as Subacapital fractures
- A fractured neck of femur (NOF) is a very common orthopaedic presentation. Over 65,000 hip fractures each year are recorded in the UK
- The mortality of a femoral neck fracture up to 30% at one year
- Cause: Neck of femur fractures are typically caused either by low energy injuries (the most common type), such as a fall in frail older patient, or high energy injuries, such as a road traffic collision
- Neck of femur (NOF) fractures can occur anywhere from the subcapital region of the femoral head to 5cm distal to the lesser trochanter
NORMAL GAIT
- Heel Strike
- Support
- Toe- off
- Leg lift
- Swing
TRENDLEBURG GAIT
During the leg lift and swing phases of walking, the body weight is placed on one limb. The key abductor muscles (the gluteus medius and gluteus minimus) contract to stop the pelvis dropping towards the raised leg, as gravity would otherwise dictate.
A patient with malfunctioning hip abductors will present with a positive Trendelenburg sign: their pelvis drops towards the side of the raised limb. The positive sign signifies that the abductor muscles on the standing limb are weakened or paralysed. For example, if the left leg was raised, and pelvic drop was observed on that side, the abductor muscles on the right leg are the cause. The injury can either be neurogenic (in which the superior gluteal nerve is damaged) or myogenic (in which the muscle fibres are stretched or weakened but the nerve remains functional). A myogenic cause can be addressed with muscle strengthening exercises and physical therapy; a neurogenic cause is more difficult and sometimes impossible to treat.
During walking, a weakness in the abductor muscles gives rise to a characteristic gait. As the pelvis drops on one side, the trunk lurches to the opposite side, in an effort to maintain balance.
During the next step, the trunk is whipped back over the pelvis towards centre. Often the momentum of this is too much for the abdominals, causing the trunk to overcompensate and fall slightly past centre to the opposite side. This highly recognisable lurching walk is called the Trendelenburg gait.
LATERAL ROTATORS
- Piriformoris
- Superior and Inferior Gemelli
- Obturator Internus and Externus
- Quadratus Femoris
- note the relationship of the sacrotuberous ligament
POSTERIOR THIGH MUSCLES
HIP - Movement and Innervation
HIP FRACTURES
- can lead to significant morbidity and mortality
Major risk factures for hip fracture:
- Increasing age
- Osteoporosis
- Females are affected more than males
- Due to the morbidity and mortality with hip fractures, they are generally prioritised on the trauma list with the aim to perform surgery within 48 hours
Hip fractures can be categorised into:
- Intra-capsular fractures
- Extra-capsular fractures
Capsule of the hip joint
The capsule of the hip joint is a strong fibrous structure. It attaches to the rim of the acetabulum on the pelvis and the intertrochanteric line on the femur. It surrounds the neck and head of the femur.
NOF / Intracapsular fracture
The head of the femur has a retrograde blood supply. The medial and lateral circumflex femoral arteries join the femoral neck just proximal to the intertrochanteric line.
Branches of this artery run along the surface of the femoral neck, within the capsule, towards the femoral head. They provide the only blood supply to the femoral head. A fracture of the intra-capsular neck of the femur can damage these blood vessels, removing the blood supply to the femoral head, leading to avascular necrosis.
Therefore, patients with a displaced intra-capsular fracture need to have the femoral head replaced with a hemiarthroplasty or total hip replacement.
Intracapsular fractures
Non-displaced intra-capsular fractures may have an intact blood supply to the femoral head, meaning it may be possible to preserve the femoral health without avascular necrosis occurring. They can be treated with internal fixation (e.g., with screws) to hold the femoral head in place while the fracture heals.
Displaced intra-capsular fractures (grade III and IV) disrupt the blood supply to the head of the femur. Therefore, the head of the femur needs to be removed and replaced.
Total hip replacement
Total hip replacement involves replacing both the head of the femur and the socket. This is generally offered to patients who can walk independently and are fit for surgery.
HEMIARTHROPLASTY
Hemiarthroplasty involves replacing the head of the femur but leaving the acetabulum (socket) in place. Cement is used to hold the stem of the prosthesis in the shaft of the femur. This is generally offered to patients who have limited mobility or significant co-morbidities
Extracapsular Frcatures
Extra-capsular fractures leave the blood supply to the head of the femur intact. Therefore, the head of the femur does not need to be replaced.
Intertrochanteric fractures occur between the greater and lesser trochanter. These are treated with a dynamic hip screw (AKA sliding hip screw). A screw goes through the neck and into the head of the femur. A plate with a barrel that holds the screw is screwed to the outside of the femoral shaft. The screw that goes through the femur to the head allows some controlled compression at the fracture site, whilst still holding it in the correct alignment. Adding some controlled compression across the fracture improves healing.
Subtrochanteric fractures occur distal to the lesser trochanter (although within 5cm). The fracture occurs to the proximal shaft of the femur. These may be treated with an intramedullary nail (a metal pole inserted through the greater trochanter into the central cavity of the shaft of the femur).
Hip fracture presentation
The typical scenario is an older patient (over 60) who has fallen, presenting with:
- Pain in the groin or hip, which may radiate to the knee
- Not able to weight bear
- Shortened, abducted and externally rotated leg
Imaging of Hip Fracture
X-rays are the initial investigation of choice. Two views are essential, as a single view can miss the fracture. Anterior-to-posterior (AP) and lateral views are standard.
Shenton’s line can be seen on an AP x-ray of the hip. It is one continuous curving line formed by the medial border of the femoral neck and continues to the inferior border of the superior pubic ramus. Disruption of Shenton’s line is a key sign of a fractured neck of femur (NOF).
MRI or CT scanning may be used where the x-ray is negative, but a fracture is still suspected.
Shentons line
Drugs in the management of MSK disorders ?
Osteoporosis
Osteoporosis involves a significant reduction in bone density.
Osteopenia
Osteopenia refers to a less severe decrease in bone density. Reduced bone density makes the bones weaker and prone to fractures.
How do we measure Osteoporosis ?
- DEXA scan: dual-energy x-ray absorptiometry)
- The World Health Organization (WHO) provide definitions based on the T-score of the femoral neck, measured on a DEXA scan.
- The T-score is the number of standard deviations the patient is from an average healthy young adult
- A T-score of -1 means the bone mineral density is 1 standard deviation below the average for healthy young adults
DEXA Scan
DEXA scans are a type of x-ray that measures how much radiation is absorbed by the bones, indicating how dense the bone is.
The bone mineral density can be measured anywhere on the skeleton, but the femoral neck reading is most important.
Bone density can be represented as a Z-score or T-score.
The Z-score is the number of standard deviations the patient is from the average for their age, sex and ethnicity.
The T-score is the number of standard deviations the patient is from an average healthy young adult. The T-score is used to make the diagnosis.
Which medications increases your likeliness of getting osteoporosis?
- Long term use of corticosteroids
Post menopausal women and osteoporosis
Post-menopausal women are an important group where osteoporosis should be considered.
Oestrogen is protective against osteoporosis but drops significantly after menopause.
Hormone replacement therapy (HRT) is protective against osteoporosis.
Tamoxifen is a selective oestrogen receptor modulator (SERM) used to treat breast cancer. It blocks oestrogen receptors in breast tissue but stimulates oestrogen receptors in the uterus and bones. It helps prevent osteoporosis but increases the risk of endometrial cancer.
Raloxifene is a SERM used to treat osteoporosis (but not breast cancer in the UK).
Treatment of Osteoporosis
1st address reversible risk factors:
- increase physical activity, stop smoking, reduce alcohol consumption
2nd step address:
- insufficient intake of calcium (less than 700mg per day)
-inadequate vitamin D (e.g., limited sun exposure)
1st line treatment:
- Bisphosphonates are the first-line treatment for osteoporosis.
Bisphosphonates side effects
- Reflux and oesophageal erosions
- Atypical fractures (e.g., atypical femoral fractures)
-Osteonecrosis of the jaw (regular dental checkups are recommended before and during treatment)
-Osteonecrosis of the external auditory canal
How to take bisphosphonates
Oral bisphosphonates are taken on an empty stomach with a full glass of water.
Afterwards, the patient should sit upright for 30 minutes before moving or eating to reduce the risk of reflux and oesophageal erosions.
Examples of bisphosphonates
Alendronate 70 mg once weekly (oral)
Risedronate 35 mg once weekly (oral)
Zoledronic acid 5 mg once yearly (intravenous)
When do you stop taking bisphosphonates for osteoporosis ?
They suggest a repeat DEXA scan and stopping treatment if the T-score is more than -2.5
Structure of the bone
Osteoporosis: The underlying cause of osteoporosis is an imbalance between bone resorption and bone formation, which are normal processes of bone remodeling.
Osteoblasts:
- Now in bone remodeling, the process begins when osteoblasts sense micro fractures near their location.
- The osteoblasts produce a substance called RANKL which binds to RANK receptors on the surface of nearby monocytes.
- RANKL induces those monocytes to fuse together to form a multinucleated osteoclast cell.
- RANKL also helps the osteoclast mature and activate so that they can start resorbing bones.
- The osteoclast starts secreting lysosomal enzymes, mostly collagenase, which digests the collagen protein in the organic matrix. This drills pits on the bone surface known as the Howship’s lacunae.
- Osteoclasts also start producing hydrochloric acid, or HCl, which dissolves hydroxyapatite into soluble calcium – Ca2+ and phosphate – PO42- ions, and these ions get released into the bloodstream.
BISPHOSPHONATES
BISPHOSPHONATES
Bisphosphonates can be divided into two groups:
- simple non-nitrogenous bisphosphonates
- potent nitrogenous bisphosphonates
What happens:
- Bisphosphonates work by binding to hydroxyapatite, which is the mineralized form of calcium found in bones.
- When osteoclasts break down bones, they also take in the bisphosphonates.
PYROPHOSPHATE (non-nitrogenous bisphosphonate)
- Simple, non-nitrogenous bisphosphonates are very similar to pyrophosphate, which is used to synthesize the ATP that provides energy in living cells.
- So, bisphosphonates work by getting added to ADP to form nonfunctional ATP analogues that don’t provide energy and instead, they build up in the osteoclast. This eventually leads to apoptosis or cell death.
- And ultimately, fewer osteoclasts mean less bone resorption.
Nitrogenous Bisphosphonates
- Nitrogenous bisphosphonates work by inhibiting the osteoclast’s mevalonate pathway, which disrupts the synthesis of cholesterol.
- Since cholesterol is important for the function of the cell membrane and many enzymes, this decrease in cholesterol causes the osteoclast to become nonfunctional.
Drug: Alendronic acid ?
Alendronic acid is a bisphosphonate medication used to treat osteoporosis and Paget’s disease of bone.
It is taken by mouth. Use is often recommended together with vitamin D, calcium supplementation, and lifestyle changes
Drug class: Bisphosphonate
After administration it distributes into soft tissue and bone or is excreted in the urineLabel. Alendronic acid does not undergo metabolism
Mechanism: Inhibition of osteoclasts results in decreased bone resorption
Drug: Alendronic acid ?
Drug: Alendronic acid
Alendronic acid is a bisphosphonate medication used to treat osteoporosis and Paget’s disease of bone.
It is taken by mouth. Use is often recommended together with vitamin D, calcium supplementation, and lifestyle changes
Drug class: Bisphosphonate
-After administration it distributes into soft tissue and bone or is excreted in the urine. Alendronic acid does not undergo metabolism
Mechanism:
- Alendronic acid binds to bone hydroxyapatite
- Inhibition of osteoclasts results in decreased bone resorption
Drug: Calciferol
aka as Vitamin D
Vitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects. In humans, the most important compounds in this group are vitamin D₃ and vitamin D₂.
Drug: HRT (Hormonal replacement therapy) ?
Hormone replacement therapy (HRT) is a treatment to relieve symptoms of the menopause. It replaces hormones that are at a lower level as you approach the menopause.
The main benefit of HRT is that it can help relieve most of the menopausal symptoms, such as:
-hot flushes
-night sweats
-mood swings
-vaginal dryness
-reduced sex drive
-Many of these symptoms pass after a few years, but they can be unpleasant and taking HRT can offer relief for many women.
It can also help prevent weakening of the bones
Drug: Raloxifene ?
Drug Class: Selective estrogen receptor modulator (SERM)
Mechanim: On skeletal tissues, raloxifene stimulates bone-depositing osteoblasts and inhibits bone-resorbing osteoclasts
- is a medication used to prevent and treat osteoporosis in postmenopausal women and those on glucocorticoids.
-For osteoporosis it is less preferred than bisphosphonates.
-It is also used to reduce the risk of breast cancer in those at high risk
Parathyroid hormone involvement in bones ?
Vitamin Ds involvement in bones ?
Moreover, osteoblasts and osteoclasts are controlled by two hormones: parathyroid hormone, which is released by parathyroid glands; and calcitonin, which is released by the thyroid gland.
At low concentrations, parathyroid hormone works by stimulating the activity of osteoblasts, thereby promoting bone formation; while at high concentrations, parathyroid hormone stimulates bone resorption.
On the other hand, calcitonin works by inhibiting osteoclast activity, thereby decreasing bone resorption
Calcitonin’s involement in bones
Which hormone decreases your likeliness of developing osteoporosis ?
Estrogens are inhibitors of bone resorption and bone remodeling and are thus protective against osteoporosis. This is thought to occur by inhibiting osteoclast differentiation and proliferation. Post-menopausal women have less protective estrogen and thus type one osteoporosis can develop at a much faster rate.
How does chronic kidney disease increase your likeliness of osteoporosis ?
Patients with chronic kidney disease (CKD) can develop renal osteodystrophy, reduced bone density, and osteoporosis through multiple mechanisms. Patients with CKD often have elevated phosphate levels and decreased serum calcium levels, resulting in increased PTH synthesis and subsequent bone resorption. CKD also results in reduced vitamin D levels through altered metabolism, further decreasing bone density.
Where are you most likely to get breaks from osteoporosis ?
The most common sites of fragility fractures secondary to osteoporosis include the spine, proximal femur (including the femoral neck), pelvis, and distal radius. Overall, vertebral fractures are the most common type of fracture from osteoporosis.
Which T-score on dual-energy x-ray absorptiometry is consistent with osteoporosis?
T-scores are used to define osteoporosis based on the average bone density of a healthy 30-year-old adult. Each integer change represents a standard deviation from this level. A T-score of ≤-2.5 defines osteoporosis and represents 2.5 deviations from the density of a 30-year-old adult.
Osteopenia: a medical condition in which the protein and mineral content of bone tissue is reduced, but less severely than in osteoporosis
Osteoporosis
-In osteopetrosis, bone resorption is impaired due to carbonic anhydrase II mutation. Carbonic anhydrase II mutations can impair the ability of osteoclasts to generate an acidic environment for normal bone resorption and remodeling, leading to thick and poorly formed bone.
Bone marrow transplantation is the most appropriate treatment option for osteopetrosis. Transplantation of marrow including normal osteoclasts and blood components may aid in the improvement, or even cure, of osteopetrosis and the associated pancytopenia.
Osteomalacia / Rickets
-Osteomalacia is a condition where defective bone mineralisation causes “soft” bones. Osteo– means bone, and –malacia means soft. It results from insufficient vitamin D.
-The same process in children causes rickets.
PAGETS DISEASE OF THE BONE
The pathophysiology of osteitis deformans is as follows: increased RANK-RANKL interaction → increased NF-κB activation → increased disorganized osteoblast and osteoclast activity → “woven bone” formation
In the clinical setting, osteitis deformans often manifests as hearing loss that occurs as a result of vestibulocochlear nerve (CN VII) compression secondary to bone formation extending into the foramina of the skull.
Osteitis deformans also classically presents with an increased hat size due to increased bone deposition in the skull.
incidence most common in central europe
On blood tests calcium and phosphate levels are normal but there is high ALS levels
Osteomyelitis
Osteomyelitis is a painful bone infection. It usually goes away if treated early with antibiotics. If not, it can cause permanent damage.
What is osteomyelitis?
Osteomyelitis is an infection that usually causes pain in the long bones in the legs.
Other bones, such as those in the back or arms, can also be affected.
Anyone can develop osteomyelitis.
You’re more at risk of getting an infection in a bone if you have:
recently broken (fractured) a bone
been injured or have a wound
an artificial hip, or a screw in a bone
recently had any surgery on a bone
a weakened immune system – for example, because of chemotherapy or you have another serious illness
had osteomyelitis before
diabetes, especially if you also have a foot ulcer
Menopause and Osteoporosis
Rhumatoid Disease
Classification of NSAIDs
DMARDs
Biological Therapies
Leg muscles
THIGH: Anterior Compartment
THIGH: Medial Compartment
Femoral Triangle
Femoral Triangle Cathertisation
Adductor Canal
Lumbar Plexus
THIGH: Posterior Compartment
GLUTE MUSCLES
SACRAL PLEXUS
Sciatic Nerve Surface Anatomy
Anterior Compartment Muscle in the leg
Lateral Crural Compartment
Posterior Crural Compartment
POPLITEAL FOSSA
SACRAL PLEXUS
MYOTOMES
NERVES VS MYOTOMES
DERMATOMES
Femoral and Sciatic Neuropathies
