Diagnosis and Management of Osteoporotic Fractures

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Epidemiology, Diagnosis
Prevention and Management of
Osteoporotic Fractures
Kenneth A. Egol, MD
NYU-Hospital For Joint Diseases
Created March 2004; Revised February 2010
Background
• Osteoporosis -- a
decreased bone density
with normal bone
mineralization
– WHO Definition (2010)1
• Bone Mineral Density ≥2.5
SD’s below the mean seen
in young normal subjects
– Incidence increases with
age 2
• 30% of white women (age
50-70) are osteoporotic
• By the age of 80, 70% are
osteoporotic
1
2
Source: www.nof.org/professionals/WHO_Osteoporosis_Summary.pdf
International Osteoporosis Center: Facts and Statistics
Background
• Risk factors for osteoporosis
–
–
–
–
–
–
–
Increasing age
Female sex
Race: Caucasian, Asian
Sedentary lifestyle
Multiple births
Excessive alcohol use
Tobacco use
Background
• Senile osteoporosis common
– Some degree of osteopenia is found in virtually all
healthy elderly patients
• Treatable causes should be investigated
–
–
–
–
–
–
Nutritional deficiency
Malabsorption syndromes (e.g., Celiac Disease, IBD)
Endocrine abnormalities (e.g., hyperparathyroidism)
Cushing’s Disease
Tumors/malignancy (e.g., Multiple Myeloma)
Medications (e.g., corticosteroids)
Background
• The incidence of osteoporotic fractures is
increasing
– Estimated that half of all women and one-third of all
men will sustain a fragility fracture during their lifetime
• By 2050  6.3
million hip fractures
will occur globally
• Costs for
osteoporosis-related
fractures expected to
increase from $19
billion in 2005
$25.3 billion in
2025.
Image courtesy of International Osteoporosis Foundation
Background
• The most common fractures in the elderly
osteoporotic patient include:
– Hip Fractures
• Femoral neck fractures
• Intertrochanteric fractures
• Subtrochanteric fractures
–
–
–
–
Ankle fractures
Proximal humerus fracture
Distal radius fractures
Image courtesy of International Osteoporosis Foundation
Vertebral compression fractures
Background
• Fractures in the elderly
osteoporotic patient
represent a challenge to
the orthopaedic surgeon
• The goal of treatment is
to restore the pre-injury
level of function
• Fracture can render an
elderly patient unable to
function independently -requiring institutionalized
care
Background
• Osteopenia complicates both
fracture treatment and healing
• Internal fixation compromised
– Poor screw purchase
– Increased risk of screw pull out
– Augmentation with methylmethacrylate
has been advocated
• Increased risk of non-union
– Bone augmentation (bone graft,
substitutes) may be indicated
Pre-injury Status
• Medical History
• Cognitive History
• Functional History
– Ambulatory status
•
•
•
•
Community Ambulator
Household Ambulator
Non-Functional Ambulator
Non-Ambulator
– Living arrangements
Pre-injury Status
• Systemic disease
– Pre-existing cardiac and pulmonary disease is
common in the elderly
– Diminishes patients ability to tolerate
prolonged recumbency
– Diabetes increases wound complications and
infection
– May delay fracture union
Pre-injury Status
• American Society of Anesthesiologists
(ASA) Classification
– ASA I- normal healthy
– ASA II- mild systemic disease
– ASA III- Severe systemic disease, not
incapacitating
– ASA IV- severe incapacitating disease
– ASA V- moribund patient
Pre-injury Status
• Cognitive Status
– Critical to outcome
– Conditions may render patient unable to
participate in rehabilitation
•
•
•
•
Alzheimer’s
CVA
Parkinson's
Senile dementia
FRAX
WHO Fracture Risk Assessment Tool
• Estimates the 10-year patient-specific absolute fracture risk
– Hip
– Major osteoporotic (spine, forearm, hip or shoulder)
• Developed by WHO to evaluate fracture risk of patients from
epidemiological data from USA, Europe, Australia and Japan
• Integrates clinical risk factors as well as BMD (femoral neck)
• Incorporated into NOF treatment guidelines and other country-specific
recommendations
• Restricted to untreated patients
Updated NOF Clinician’s Guide
Incorporation of WHO Algorithm
Previous
NOF Guide (2003)
Initiate treatment in PM
women with:
•T-score ≤-2.0 with no risk
factors
•T-score <-1.5 with ≥1 risk
factors
•Hip or vertebral fracture
New NOF Guide (2008)
Initiate Treatment in PM women and men
age ≥50 with:
•Hip or vertebral fracture
•Other prior fracture and low bone mass
(T-score -1.0 to -2.5)
•T-score <-2.5 (2º causes excl.)
•Low bone mass and 2º causes associated
with high risk of fracture
•Low bone mass AND 10-yr hip fracture
probability ≥3% or 10-yr major OP-related
fracture probability of ≥20%
Hip Fractures
• General principles
– Most common fragility fracture
– With the aging of the American population the
incidence of hip fractures is projected to
increase from 250,000 in 1990 to 650,000 by
2040
– Cost approximately $8.7 billion annually
– 20% higher incidence in urban areas 1
– 15% lifetime risk for white females who live to
age 80 1
1
International Osteoporosis Center: Facts and Statistics
Hip Fractures
• Epidemiology
– Incidence increases after age 50
– Female: male ratio is 2:1
– Femoral neck and intertrochanteric fractures
seen with equal frequency
Image courtesy of International Osteoporosis Foundation
Hip Fractures
• Radiographic
evaluation
– Anterior-posterior
view
– Cross table lateral
– Internal rotation view
will help delineate
fracture pattern
Hip Fractures
• Other imaging modalities
– Occult hip fracture
• Technetium bone scanning is a sensitive indicator,
but may take 2-3 days to become positive
• Magnetic resonance imaging has been shown to be
as sensitive as bone scanning and can be reliably
performed within 24 hours
Hip Fractures
• Management
– Prompt operative stabilization
• Operative delay of > 24-48 hours increases one-year mortality
rates
• However, important to balance medical optimization and
expeditious fixation
– Early mobilization
• Decrease incidence of decubiti, UTI, atelectasis/respiratory
infections
– DVT prophylaxis
Hip Fractures
• Outcomes
– Fracture related outcomes
• Healing
• Quality of reduction
– Functional outcomes
• Ambulatory ability
• Mortality (25% at one year for age > 50)
• Return to pre-fracture activities of daily living
Hip Fractures
• Femoral neck fractures
– Intracapsular location
– Vascular Supply
• Primary blood supply to the
femoral head is the deep branch
of the medial femoral
circumflex artery
• Medial and lateral circumflex
vessels anastomose at the base
of the neck
• Blood supply predominately
from ascending arteries (90%)
• Artery of ligamentum teres
(10%)
Hip Fractures
• Femoral neck fractures
• Treatment
– Non-displaced/ valgus impacted fractures
• Non-operative: 8-15% displacement rate
• Operative with cannulated screws
• Complications: Non-union (5%) and osteonecrosis (8%)
Hip Fractures
• Femoral neck fractures
– Displaced fractures should be treated operatively
– Treatment: Open vs. closed reduction and internal
fixation
• 30% non-union and 25%-30% osteonecrosis rate
• Non-union requires reoperation 75% of the time while
osteonecrosis leads to reoperation in 25% of cases
Hip Fractures
• Femoral neck fractures
• Treatment:
– Total Hip Arthroplasty
• Now standard for younger elderly active patients
– Hemiarthroplasty
• Unipolar vs Bipolar
• Can lead to acetabular erosion, dislocation, infection
Hip Fractures
• Femoral neck fractures
• Treatment
– Displaced fractures can be treated non operatively in certain situations
• Demented, non-ambulatory patient
– Mobilize early
• Accept resulting non or malunion
Hip Fractures
• Intertrochanteric fractures
– Extracapsular (well vascularized)
– Region distal to the neck between the
trochanters
– Fracture patterns creating increased
instability
•
•
•
•
Calcar femorale involvement
Posteromedial cortex involvement
Lateral wall involvement
Reverse obliquity pattern or subtrochanteric
extension
– Important muscular insertions
Hip Fractures
• Intertrochanteric fractures
– Treatment
• Generally treated surgically
• Common implants include sliding hip
screw and sliding cephalomedullary rod
• These implants allows for controlled
impaction upon weight bearing
Hip Fractures
• Intertrochanteric fractures
– Treatment
• Primary prosthetic
replacement can be
considered in select cases
with significant comminution
although fixation is much
more common
Hip Fractures
• Subtrochanteric Fractures
– Begin at or below the level
of the lesser trochanter
– Typically higher energy
injuries seen in younger
patients
– Far less common in the
elderly
– Increasingly more common
with long term use of
bisphosphonates (Lenart et
al. NEJM 2008)
Hip Fractures
• Subtrochanteric Fractures
– Treatment
• Intramedullary nail (high rates of
union)
• Plates and screws
Ankle Fractures
• Common injury in the elderly
– Significant increase in the
incidence and severity of
ankle fractures over the last
20 years
• Low energy injuries
following twisting reflect the
relative strength of the
ligaments compared to
osteopenic bone
Ankle Fractures
• Epidemiology
– Finnish Study (Kannus et al)
• Three-fold increase in the number of ankle fractures
among patients older than 70 years between 1970 and
2000
• Increase in the more severe Lauge-Hansen SE-4 fracture
– In the United States, ankle fractures have been reported to
occur in as many as 8.3 per 1000 Medicare recipients
• Figure that appears to be steadily rising.
Ankle Fractures
• Presentation
–
–
–
–
Follows twisting of foot relative to lower tibia
Patients present unable to bear weight
Ecchymosis, deformity
Careful neurovascular exam must be performed
Ankle Fractures
• Radiographic evaluation
– Ankle trauma series
includes:
• AP
• Lateral
• Mortise
– Examine entire length of
the fibula
Ankle Fractures
• Treatment
– Isolated, non-displaced malleolar fracture
without evidence of disruption of syndesmotic
ligaments treated non-operatively with full
weight bearing
– May utilize walking cast or cast brace
Ankle Fractures
• Treatment
– Unstable fracture patterns with bimalleolar
involvement, or unimalleolar fractures with
talar displacement must be reduced
– Closed treatment requires a long leg cast to
control rotation
• May be a burden to an elderly patient
Ankle Fractures
• Treatment
– Irreducible fractures require
open reduction and internal
fixation
– The skin over the ankle is thin
and prone to complication
– Await resolution of edema to
achieve a tension free closure
Ankle Fractures
• Treatment
– Fixation may be suboptimal due to osteopenia
• May have to alter standard operative techniques
• Locked plates, multiple syndesmotic screws
– Reports in literature mixed
• Early studies showed no difference in operative vs non-op
treatment -- with operative groups having higher complication
rates
• More recent studies show improved outcomes in operatively
treated group
– Goal is return to pre-injury functional status
Proximal Humerus
• Background
–
–
–
–
–
Very common fracture seen in geriatric populations
112/100,000 in men
439/100,000 in women
Result of low energy trauma
Goal is to restore pain free range of shoulder motion
Proximal Humerus
• Epidemiology
– Data suggest that fracture of proximal humerus
is the 3rd most common fracture over age 65
– Incidence rises dramatically beyond the fifth
decade in women
– 76% of all proximal humerus fractures occur in
patients older than 60 1
– Associated with
• Frail females
• Poor neuromuscular control
• Decreased bone mineral density
1
International Osteoporosis Center: Facts and Statistics
Proximal Humerus
• Background
– Articulates with the glenoid portion of the
scapula to form the shoulder joint
– Four parts
– Combination of bony, muscular, capsular and
ligamentous structures maintains shoulder
stability
– Status of the rotator cuff is key
Proximal Humerus
• Radiographic evaluation
–
–
–
–
AP
Scapula Y
Axillary
CT scan can be helpful
Proximal Humerus
• Treatment
– Minimally displaced (one part fractures)
usually stabilized by surrounding soft tissues
• Non operative: 91% good to excellent results
Proximal Humerus
• Treatment
– Isolated lesser tuberosity fractures require
operative fixation only if the fragment contains
a large articular portion or limits internal
rotation
– Isolated greater tuberosity associated with
longitudinal cuff tears and require ORIF if
significantly displaced
Proximal Humerus
• Treatment
– Displaced surgical neck fractures can be treated
closed by reduction under anesthesia with Xray guidance
• Anatomic neck fractures are rare but have a high
rate of osteonecrosis
– If acceptable closed reduction is not attained,
open reduction should be undertaken
Proximal Humerus
• Treatment
– Closed treatment of 3 and 4 part fractures have
yielded poor results
– Failure of fixation is a problem in osteopenic
bone
• Locked plating versus prosthetic replacement
Proximal Humerus
• Treatment
– Regardless of treatment all require prolonged,
supervised rehabilitation program
– Poor results are associated with rotator cuff tears,
malunion, nonunion
– Prosthetic replacement can be expected to result in
relatively pain free shoulders
– Functional recovery and ROM variable
Distal Radius
• Background
– Very common fracture
in the elderly
– Result from low
energy injuries
– Incidence increases
with age, particularly
in women
– Associated with
dementia, poor
eyesight and a decrease
in coordination
Distal Radius
• Epidemiology
– Increasing in incidence
• Especially in women
–
–
–
–
–
125/100,000
Peak incidence in females 60-70
Lifetime risk is 15%
Most frequent cause: fall on outstretched arm
Decreased bone mineral density is a factor
Distal Radius
• Radiographic evaluation
–
–
–
–
PA
Lateral
Oblique
Contralateral wrist
• Important to evaluate deformity, ulnar variance
Distal Radius
• Treatment
– Non-displaced fractures may be immobilized
for 6-8 weeks
– Metacarpal-phalangeal and interphalangeal
joint motion must be started early
Distal Radius
• Treatment
– Displaced fractures should be reduced with
restoration of radial length, inclination and tilt
• Usually accomplished with longitudinal traction
under hematoma block
– If satisfactory reduction is obtained, treatment
in a long arm or short arm cast is undertaken
• No statistical difference in method
– Weekly radiographs are required
Distal Radius
• Treatment
– If acceptable reduction not obtained
– Regional or general anesthesia
– Methods
• ORIF
• Closed reduction and percutaneous pinning with
external fixation
Distal Radius
• Treatment
– Results are variable and depend on fracture
type and reduction achieved
– Minimally displaced and fractures in which a
stable reduction has been achieved result in
good functional outcomes
Distal Radius
• Treatment
– Displaced fractures treated surgically produce
good to excellent results 70-90%
– Functional limits include pain, stiffness and
decreased grip
Vertebral Compression Fractures
• Background
– Nearly all post-menopausal women over age 70
have sustained a vertebral compression fracture
– Usually occur between T8 and L2
– Kyphosis and scoliosis may develop
• Markers for osteoporosis
Vertebral Compression Fractures
• Epidemiology
– Estimated that only 1/3 of
vertebral fractures come to
clinical attention – highly
underreported
– Prevalence similar for men
and women age 60-70
– 117/100,000
– A 50 year old white
woman has a 16% lifetime
risk of experiencing a
vertebral fracture
Image courtesy of International Osteoporosis Foundation
Vertebral Compression Fractures
• Background
– Present with acute back pain
– Tender to palpation
– Neurologic deficit is rare
• Patterns
– Biconcave (upper lumbar)
– Anterior wedge (thoracic)
– Symmetric compression (T-L
junction)
Vertebral Compression Fractures
• Radiographic
evaluation
– AP and lateral
radiographs of the
spine
– Symptomatic vertebrae
1/3 height of adjacent
– Bone scan can
differentiate old from
new fractures
Vertebral Compression Fractures
• Treatment
– Simple osteoporotic vertebral compression
fractures are treated non-operatively and
symptomatically
– Prolonged bedrest should be avoided
– Progressive ambulation should be started early
– Back exercises should be started after a few
weeks
Vertebral Compression Fractures
• Treatment
– A corset may be helpful
– Most fractures heal uneventfully
– Kyphoplasty an option
Prevention
• Strategies focus on controlling
factors that predispose to recurrent
fracture
– Consider bone mineral density test
– Rule out secondary causes of
osteoporosis
– Initiate and monitor therapy, or refer
• Fall prevention
Prevention
• Multidisciplinary programs
–
–
–
–
Medical adjustment
Behavior modification
Exercise classes
Controversial
Prevention and Treatment of
Bone Fragility
• Well established link between decreasing
bone mass and risk of fracture
• Prevention/treatment options
Bisphosphonates
-Alendronate (Fosamax ®)
-Risedronate (Actonel ®)
-Ibandronate (Boniva ®)
-Zolendronate (Aclasta ®)
SERMs
- Raloxifene (Evista ®)
Hormone Therapy/Replacement
- Estrogen/progestin
Other
- Calcitonin
Stimulators of bone formation
- rh-PTH (Forteo ®)
Prevention and Treatment of
Bone Fragility
• Estrogen/progestin
– FDA approved for prevention, not treatment of
osteoporosis
– 3-5% bone loss/year with menopause
– Unopposed or combined therapy has been shown to
reduce hip fracture incidence in women aged 65-74 by
40-60% (Henderson et al. 1988)
– However, the Women’s Health Initiative (2009)
concluded reduction in hip fracture not offset by
increased risk of breast & endometrial cancers,
thromboembolism, dementia, and coronary heart
disease
Prevention and Treatment of
Bone Fragility
• Calcium/Vitamin D Supplementation
– Recommended for most men and women >50 years
• Calcium
– Age <50 -- 1,000 mg/day
– Age >50 -- 1,200 mg/day
• Vitamin D
– Age < 50 – 400-800 IU/day
– Age >50 – 800-1000 IU/day
• Combining Vitamin D and calcium supplementation
has been shown to increase bone mineral density and
reduce the risk of fracture
Prevention and Treatment of
Bone Fragility
• Calcitonin
– Inhibits bone resorption by inhibiting osteoclast activity
– Approved for treatment of osteoporosis in women who have
been post-menopausal for > 5 years
• Daily intranasal spray of 200 IU
– Trial demonstrated 33% reduction of vertebral compression
fractures with daily therapy (Chesnut Am J Med 2000)
– Calcitonin is indicated for no longer than 24
months in the United States to prevent “resistance”
Prevention and Treatment of
Bone Fragility
• Bisphosphonates
– Inhibits bone resorption by reducing osteoclast recruitment
and activity
– Bone formed while on bisphosphonate therapy is
histologically normal
• Strongest evidence for rapid fracture risk reduction
– Decreasing the incidence of both vertebral and nonvertebral
fractures
• Recent evidence of increased risk of subtrochanteric
insufficiency fractures with long term use (Lenart et al.
NEJM 2008)
Prevention and Treatment of
Bone Fragility
•
Alendronate
– Shown to increase the bone density in
femoral neck in post menopausal
women with osteoporosis (Lieberman
et al. NEJM 1995)
– Fracture Intervention Trial (FIT)
demonstrated daily Fosamax for 3
years significantly reduced the risk of
vertebral fracture by 47% and of hip
fracture by 51% in women with low
BMD and previous vertebral fracture
(Black et al. Lancet 1996)
– Recently associated with lateral
cortical stress fractures following long
term use.
Prevention and Treatment of
Bone Fragility
• Teriparatide (Forteo)
– Recombinant formulation of
parathyroid hormone
– Stimulates the formation of new
bone by increasing the number
and activity of osteoblasts
– Once daily subcutaneous
injection of 20 g
• Study of 1637 post-menopausal
women
– 65% reduction in the incidence of
new vertebral fractures
– 53% reduction in the incidence of
new nonvertebral fractures
Conclusions
• Prevention is multifaceted: a fragility fracture is
the strongest predictor of a future fracture
• Cost containment is a joint effort between
orthopaedists, primary care physicians, PT and
social work
• Functional outcome is maximized by early
fixation and mobilization in operative cases
• With the increasing population of elderly,
orthopaedic surgeons must be proactive in
secondary prevention of fragility fractures
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General/Principles
Index
Recommended Reading
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•
•
•
•
•
•
Turner CH. Biomechanics of bone: determinants of skeletal fragility and bone
quality. Osteoporos Int 13:97–104, 2002.
Kleerekoper M. Osteoporosis prevention and therapy: preserving and building
strength through bone quality. Osteoporos Int 17:1707–1715, 2006.
www.nof.org/professionals/WHO_Osteoporosis_Summary.pdf
Haidukewych GJ, et al. Reverse obliquity fractures of the intertrochanteric
region of the femur JBJS 83A: 643-50, 2001.
Koval KJ, et al. Postoperative weight-bearing after a fracture of the femoral
neck or an intertrochanteric fracture. JBJS 80A: 352-6, 1998.
Baumgaertner MR, et al. The value of the tip-apex distance in predicting failure
of fixation of peritrochanteric fractures of the hip JBJS 77A:1058-1064, 1995.
Chan SS, et al. Subtrochanteric femoral fractures in patients receiving long-term
alendronate therapy: imaging features. AJR 2010; 194:1581–1586
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