John E' Herzenberg, MD

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Multiplier Method for the Prediction of Sitting
Height and Spinal Height
John E. Herzenberg, MD Mordchai B. Shualy Maya
Goldberg Dror Paley, MD Amanda Gelman The
International Center for Limb Lengthening Rubin
Institute for Advanced Orthopedics Sinai Hospital
of Baltimore Baltimore, Maryland,
USA www.limblengthening.org
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The multiplier method is a tool that is used to
predict a childs height or limb length at
maturity.
Multiplier Length _at_ maturity
Length _at_ each age
Lmaturity M x Lcurrent age
70 cm
86.8 cm at maturity

x
1.240
11-year-old boy
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• Multipliers have been calculated for
• Height (normal)
• Height (dwarf)
• Limb length
• Foot length
• Arm length
• Fetal limb length
• This study presents calculations for
• Sitting Height

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Purpose of Study

• Calculate sitting height and spinal multipliers
• Test if these multipliers are independent of
  percentile, race, nationality, and generation
• Develop a method to predict height loss after
  spinal fusion

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Comparison of Multipliers from Sitting Height
Databases Consisting of Males
Multiplier
Age
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Sitting Height vs. Thoracic and Lumbar Multipliers
Multiplier
Age (years)
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(No Transcript)
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Spinal Fusion

• To predict height of single lumbar vertebrae

((Leach age)M)/5 LMaturity

• To predict height of single thoracic vertebrae
• ((Leach age)M)/12 LMaturity

• To predict growth remaining
• (M(L-1) growth remaining)

not yet tested
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Conclusions

• Sitting height (spinal) multiplier is independent
  of
• Percentile
• Nationality and race

• Lumbar and thoracic vertebrae multipliers are
• similar to
• sitting height multiplier
• Cervical spine multiplier is
• similar to
• upper extremity multiplier

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For more information contact Dror Paley, MD,
FRCSC Director, Rubin Institute for Advanced
Orthopedics Co-Director, The International Center
for Limb Lengthening 2401 West Belvedere
Avenue Baltimore, MD 21215-5271 USA Tel
800-221-8425 dpaley_at_lifebridgehealth.org
www.limblengthening.org www.deformitycourse.com