Transcript Radius of Gyration as possible parameter for adjusting

Medical Vibration Therapy in Osteopenic
patients with Galileo900/2000
S.F.E. Praet MD MSc
Trainee Sports Medicine
Movement Scientist
Máxima Medical Centre
Veldhoven (Nl)
H. Mulder, MD PhD
Endocrinologist
Director Osteosupport SMO
Rotterdam (Nl)
N. Snelder, BSc
Masters student
Life Science and Technology
TU Delft / RU Leiden (Nl)
Overview
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Introduction
Background
Research Question
Methods
The Galileo™ principle
Results
Discussion
Summary
Introduction
Definition of Bone Mineral Density
(WHO)
Healthy Bone = Reference BMD of 25 yrs old female
(T-score < -1)
Osteopenic = BMD < 1 SD of reference BMD
(T-score < -1)
Osteoporotic = BMD < 2.5 SD
(T-score < -2.5)
Introduction
Natural BMD at Hip in Caucasian Females
Introduction
Epidemiology of Osteoporosis
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Approximately 30% of postmenopausal females have
osteoporosis according to the World Health Organization
(WHO) (Kanis 1994, WHO 1994).
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The excess mortality associated with a hip fracture has
been estimated to be at 20% (Cooper 1993),
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Cumulative lifetime fracture risk for a 50 year-old women
may be as high as 60% (Cummings 1989).
Introduction
Bone Mineral Density vs. Risk of Hip fracture
Introduction
Cost of Osteoporosis
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The total dollar cost of osteoporosis was estimated at seven
to ten billion annually in 1988 (WHO 1994).
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Hip fractures and hospitalization for all types of fracture
accounted for most of these costs (Cooper 1993).
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Therefore, the prevention of fractures is the primary goal of
intervention.
Introduction
Prevention of Osteoporosis
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Anti-resorptive bone formation agents
(e.g. estrogen and biophosphates)
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Bone formation agents (e.g. fluoride and PTH).
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Calcium and Vitamin D supplementation
JAMA 285: 785-795, 2001
Chapuy et al. Osteoporos. Int. 2002
Introduction
Osteoporosis & Calcium
Introduction
Prevention of Osteoporosis
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“The value of exercise as an intervention for the prevention
of postmenopausal bone loss is a controversial subject”
Kanis, WHO Study Group. Osteoporosis Int. 1994
Introduction
Osteoporosis & Exercise:
Background
Vibrations and Bone mass
Animal studies (Turkey)
Rubin et al. Nature 2001
Fritton, McLeod, Rubin, J. Biomech. 2000
Background
Normal Frequency & Microstrain Pattern in Bone
Animal studies (Turkey/Sheep/Dog)
Walking Turkey
12 h. Daily activity
1 microstrain is 0.0001% strain (e = dL/L)
Fritton, McLeod, Rubin, J. Biomech. 2000
Background
Vibrations and Bone mass
Animal studies (Ewes)
30Hz, 0.3 g, 20min/day
5x/wk during 1 year
Femur: 34.2% BMD increase
Tibia: 26.7% Strength increase
Rubin et al. Bone 2002
Rubin et al. J Bone Miner. Res. 2002
Background
Vibrations and Bone mass
Animal studies: Bone Formation (Prox. Tibia) in Rats
28 days follow up period:
LTC=Long term control
MS=Mech. Stim/ @ 90Hz 0.25 g
10 min/day 5x/wk
Dis= Disuse Hindlimb suspension
WB=Weight Bearing
Rubin et al. FASEB 2001
Background
Vibrations and Bone mass
Animal studies: Mineralization of Trabuculae
Control
Disuse
Mech. Stim.
Rubin et al. FASEB 2001
Research Question
What is the effect of Vibration Therapy
on patients with low bone mass?
Methods
Subjects Selection
Inclusion Criteria:
•Osteopenia: BMD –2.0 < t-value < 1.0 (DEXA)
•Able to stand on vibration platform
•Motivation to participate
Exclusion Criteria:
•Use of Medication that influences Bone metabolism
•History of Deep Venous Thrombosis
Methods
Subjects Selection
January 2001- April 2001
•60 patients visiting Osteoporosis Clinic for DEXA measurement
with osteopenia (-2.0 < t < -1.0)
•37 patients included
•23 patients excluded
•10 not allowed medication
•3 History of DVT
•3 Disabled
•7 Not interested to participate
Methods
Therapeutical Intervention through Randomization
Group I (n=19 (13 F / 6 M)
Group II (n=18 (13 F / 5 M)
Age: 61 yrs ± 7
Age: 64 yrs ± 5
10 post menopausal
8 post menopausal
•WBV on Galileo2000
•WBV on Galileo2000
1x/week: 3 x 3 min @16 Hz
1x/week: 3 x 3 min @16 Hz
•Vitamin D 400 I.U. / day
•Calcium 500 mg / day
Whole Body Vibration Platform
Galileo ™ 900/2000
•Amplitude: 0-12 mm
•Frequency 5-30 Hz (continuum)
•Tilting platform
Whole Body Vibration
Whole Body Vibration
according to Galileo principle
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Downward displacement / Acceleration of leg
Reactive upward force (cf. landing phase)
Dampening through:
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Eccentric muscle contraction:
alternating left / right limb +
contralateral trunk muscles
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Simultaneous Bone strain
Methods
BMD measurements
Dual Energy X-Ray Absorptiometry (DEXA)
•Lunar DPX-L machine
At 0 – 6 – 12 and 24 months
Hip (Neck)
Lumbar spine
(L1-L4)
Methods
Marker Bone Growth
Serum Alkaline Phosphatase measurements
At 0 – 12 and 24 months
Statistics
Multiple t-tests within and between the two groups
Confidence interval 99%
Results
Serum Alkaline Phosphates
Serum Alkaline Phosphates
110,0%
**
108,0%
**
106,0%
104,0%
102,0%
Change Alkaline Phosphates I
100,0%
Change Alkaline Phosphates II
98,0%
96,0%
94,0%
0
12
Months
* p<0.01
24
Results
BMD change Spine
BMD L1-L4
108,0%
¶
107,0%
106,0%
105,0%
*
¶
104,0%
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*
103,0%
Change BMD Spine I
Change BMD Spine II
102,0%
101,0%
100,0%
99,0%
98,0%
0
6
12
Months
¶ p<0.01, * p<0.001
24
Results
BMD change Hip
BMD Femoral Neck
108,0%
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107,0%
106,0%
105,0%
¶
¶
*
¶
104,0%
Change BMD Hip I
103,0%
Change BMD Hip II
102,0%
101,0%
100,0%
99,0%
98,0%
0
6
12
Months
¶ p<0.01, * p<0.001
24
Results
Percentual BMD change
0
6
12
24
Spine group 1
Hip group 1
Percental change in bonemass
100,0%
100,0%
101,0%
101,7% ¶
101,8% ¶
103,3%*
102,1% ¶
103,6% ¶
0
6
12
24
Spine group 2
Hip group 2
Percental change in bonemass
100,0%
100,0%
101,3% *
102,0% *
103,1%
104,2%
*
*
104,0% ¶
103,9% ¶
Months
I
Months
II
¶ p<0.01, * p<0.001
Results
Bone Mineral Density change (DEXA)
104,5%
104,0%
103,5%
103,0%
102,5%
102,0%
101,5%
101,0%
100,5%
100,0%
0
6
Spine group 1
Hip group 1
months
12
Spine group 2
24
Hip group 2
Percental change in bonemass (spine and femoral neck of the hip) in patients with Osteopenia,
treated with WBV without (group 1) and with calcium-vitamin D supplementation (group 2)
Results
Therapy compliance
Compliance to the Whole Body Vibration protocol
Table IV
52 weeks
104 weeks
Group I
94%
92%
group II
93%
90%
Note: Medical Vibraion Therapy each weak = 100%
Reported side effects: none
Other Literature
8 Months of Vertical WBV @ 25-45 Hz
in young healthy adults vs controls (RCT, n=56)
2-5x/wk, 4 min/day
•No effect on BMC (DEXA/pQCT)
•No effect on Serum Bone Turnover Markers
•7.8 % net increase in Jump Height
Torvinen et al, J Bone Miner Res 2003 May 18:876-84
Other Literature
Strength training vs. Tilting WBV @ 25 Hz
12 mths, 2x/wk +/- HRT post-menopausal (n=51)
Spine
Hip
C. Kleinmond, PhD Thesis FU Berlin, 2002
http://darwin.inf.fu-berlin.de/2002/270
Discussion
Whole Body Vibration and Bone Metabolism
•Catabolic vs Anabolic state of Bone
•Secondary/functional hypoparathyreoidism
•Pre vs Post menopausal
•Base line BMD / Activity level
Discussion
Whole Body Vibration and Bone Metabolism
•Synergistic Effect with
•Ca++/Vit D
•Hormone Replacement Therapy
Discussion
Whole Body Vibration and Bone Metabolism
Dose-response relationship ?
•Frequency
•Duration
•Amplitude
•Vertical vs Tilting
•Therapy Compliance
Discussion
Whole Body Vibration and Bone Cell
Theoretical Model of Osteogenesis and Vibration:
Perturbation Intermedullary Pressure
Fluid flow through bone canuculi /lacunae
Shear Stress Cell Membrane
(>5 microstrain @ 30 Hz)
Mechanotransduction
Cytoskeletal stress
Expression of mRNA
Osteoblast expression /activation
Weinbaum et al. J. Biomech. 27, 1993
Hsich& Turner J Bone Miner Res 16, 2001
Rubin et al Nature 412, 200/ Bone 30, 2002
Qin, Rubin, McLeod J Orth Res 16 1998
Cullen et al. J. Appl. Physiol 91, 2001
WBV and Fall risk
• ADL in Geriatric patients (Balance + chair rising test)
(n=34, 67 yrs; 2 mths: 3x/wk 3 x 2 min WBV)
+ 18 % progress in Chair rising test
Runge et al. ; J. Musculoskeletal Interact. 1 (2000)
Summary
Whole Body Vibration in Osteopenia
•Synergistic effect of WBV and Ca++/Vit D Supplementation
•Fast response at Femoral Neck
•Long term response at Lumbar Spine
•Leveling off after 12 months
•Optimal dose response?
•Fall and fracture risk reduction: still undetermined
Thank you for your attention