Jump-In: Building Better Bones

Adolescent Development Clinical Trial

Official title:

Exercise and Bone Development in Young Girls

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00729378
• Other study ID #: HD050775
• Status: Completed
• Phase: N/A
• Start date: April 2007
• Est. completion date: April 2013

Study information

• Verified date: March 2021
• Source: Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The Jump-In study will prospectively assess the effects of impact exercise on skeletal development in young girls, including bone mass, bone mineral density, and bone geometry. We hypothesize that girls who regularly participate in impact loading exercise will accrue greater skeletal mass, increase bone density and undergo structural adaptations that in combination will improve bone strength compared to girls who do not participate in impact exercise.

Description:

Jump-In is a school-based, block-randomized, trial of the effects of impact-loading exercise on skeletal development in prepubescent and early pubescent girls. Fourth (n=~200) and sixth (n=~200) grade girls in 14 Tucson (Arizona) schools with no contraindication to physical exercise will be enrolled. Girls in intervention schools will participate in impact activities 3 times per week at school, progressively increasing the number (up to 40) of jumps and their height (from 6 inches to 18 inches per repetition) over the initial 2 months. Thereafter, new activities will be introduced approximately every 2-3 months to maintain interest and motivation, and continually stress the skeleton in novel ways, over 2 years of intervention. Physical and behavioral assessments will be done in both intervention and control groups at baseline, end of the initial school year, and yearly thereafter for 5 years. Assessments include height and weight, selected skeletal lengths, fat, lean soft tissue, bone mineral content and areal density from dual energy x-ray absorptiometry (DXA), and bone geometry (e.g., cortical thickness, periosteal circumference and cortical and trabecular density) and muscle area from peripheral quantitative computed tomography (pQCT). Also, maturation will be assessed via the Tanner Stage (self-assessment against standardized drawings of stages of physical development), diet from the Harvard Youth Food Frequency Questionnaire, and physical activity using pedometers and standardized questionnaires. We hypothesize that girls in intervention schools will demonstrate enhanced skeletal development, including greater mineral mass and density, and enhanced bone geometry, leading to greater bone strength compared to girls in control schools. We further hypothesize that younger (Tanner Stage 1) girls will experience greater adaptations than older girls (Tanner 2 and 3), and that positive adaptations will be maintained throughout the 3-year follow-up period.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 509
• Est. completion date: April 2013
• Est. primary completion date: April 2012
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 9 Years to 12 Years

Eligibility

Inclusion Criteria:

female; entering 4th or 6th grade at enrollment; and willing and able to undergo all of the testing requirements; no physical conditions that limit participation in physical activity/exercise; able to read and write English.

Exclusion Criteria:

Girls with severe learning disabilities (identified by schools), who are unable to complete questionnaires or otherwise comply with assessment protocols will be excluded. Any subjects (or potential subjects) suffering from medical conditions and/or disabilities that would limit their participation in exercise will be excluded from the study, following the American Academy of Pediatrics (AAP) guidelines. Further, any volunteers who are taking medications that would limit exercise and/or alter bone mineral accrual will also be excluded from the study. Girls with a positive pregnancy screening test at the time of the lab visit before DXA scanning will be excluded.

Related Conditions & MeSH terms

• Adolescent Development

Intervention

Other:
• Skeletal loading
Impact activities, 3 times per week, increasing the number of jumps (up to 40) and increasing height (from 6 inches to 24 inches per repetition) over the initial 8-weeks (2 months). New activities will be introduced approximately every 2-3 months in order to continually stress the skeleton over 2 years.

Locations

Country	Name	City	State
United States	University of Arizona-Ina Gittings Bldg. #93	Tucson	Arizona

Sponsors (1)

Lead Sponsor	Collaborator
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Baseline Total Volumetric Bone Density at the Femur 4% Site	Baseline (initial) measurement of total volumetric bone density at the femur 4% site. Measurement made by peripheral quantitative computed tomography (pQCT) at a distance of 4% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Volumetric Bone Density of Trabecular Bone at the Femur 4% Site	Baseline (initial) measurement of volumetric bone density of trabecular bone at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Volumetric Bone Density of Cortical Bone at the Femur 4% Site	Baseline (initial) measurement of volumetric bone density of Cortical bone at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Trabecular Bone Area at the Femur 4% Site	Baseline (initial) measurement of trabecular bone area at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: square millimeters (mm^2).	Baseline
Primary	Baseline Cortical Bone Area at the Femur 4% Site	Baseline (initial) measurement of cortical bone area at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: square millimeters (mm^2).	Baseline
Primary	Baseline Periosteal Circumference at the Femur 4% Site	Baseline (initial) measurement of periosteal circumference at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: millimeters (mm).	Baseline
Primary	Baseline Bone Strength Index at the Femur 4% Site	Baseline (initial) measurement of bone strength index (BSI) at the femur 4% site. Bone Strength Index (BSI) is a measurement of the resistance to compression forces at the epiphyses of long bones. Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: mm^4.	Baseline
Primary	Baseline Total Volumetric Bone Density at the Femur 20% Site	Baseline (initial) measurement of total volumetric bone density at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Volumetric Bone Density of Trabecular Bone at the Femur 20% Site	Baseline (initial) measurement of volumetric bone density of trabecular bone at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Volumetric Bone Density of Cortical Bone at the Femur 20% Site	Baseline (initial) measurement of volumetric bone density of Cortical bone at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Periosteal Circumference at the Femur 20% Site	Baseline (initial) measurement of periosteal circumference at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: millimeters (mm).	Baseline
Primary	Baseline Cortical Thickness at the Femur 20% Site	Baseline (initial) measurement of cortical thickness at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: millimeters (mm).	Baseline
Primary	Baseline Stress-Strain Index at the Femur 20% Site	Baseline (initial) measurement of stress-strain index at the femur 20% site. Stress-strain index (also called strength-strain index and stress-strength index in the literature) is a measure of the resistance to torsional and bending forces at diaphyseal sites of long bones. Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: mm^3.	Baseline
Primary	Baseline Volumetric Bone Density of Trabecular Bone at the Tibia 4% Site	Baseline (initial) measurement of volumetric bone density of trabecular bone at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Total Volumetric Bone Density at the Tibia 4% Site	Baseline (initial) measurement of total volumetric bone density at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Volumetric Bone Density of Cortical Bone at the Tibia 4% Site	Baseline (initial) measurement of volumetric bone density of cortical bone at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Trabecular Bone Area at the Tibia 4% Site	Baseline (initial) measurement of trabecular bone area at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: square millimeters (mm^2).	Baseline
Primary	Baseline Cortical Bone Area at the Tibia 4% Site	Baseline (initial) measurement of cortical bone area at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: square millimeters (mm^2).	Baseline
Primary	Baseline Periosteal Circumference at the Tibia 4% Site	Baseline (initial) measurement of periosteal circumference at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline
Primary	Baseline Bone Strength Index at the Tibia 4% Site	Baseline (initial) measurement of bone strength index (BSI) at the tibia 4% site. Bone Strength Index (BSI) is a measurement of the resistance to compression forces at the epiphyses of long bones. Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: mm^4.	Baseline
Primary	Baseline Total Volumetric Bone Density at the Tibia 50% Site	Baseline (initial) measurement of total volumetric bone density at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Volumetric Bone Density of Trabecular Bone at the Tibia 50% Site	Baseline (initial) measurement of volumetric bone density of trabecular bone at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Volumetric Bone Density of Cortical Bone at the Tibia 50% Site	Baseline (initial) measurement of volumetric bone density of cortical bone at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Periosteal Circumference at the Tibia 50% Site	Baseline (initial) measurement of periosteal circumference at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline
Primary	Baseline Cortical Thickness at the Tibia 50% Site	Baseline (initial) measurement of cortical thickness at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline
Primary	Baseline Stress-Strain Index at the Tibia 50% Site	Baseline (initial) measurement of stress-strain index at the tibia 50% site. Stress-strain index (also called strength-strain index and stress-strength index in the literature) is a measure of the resistance to torsional and bending forces at diaphyseal sites of long bones. Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: mm^3.	Baseline
Primary	Baseline Total Volumetric Bone Density at the Tibia 66% Site	Baseline (initial) measurement of total volumetric bone density at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Volumetric Bone Density of Trabecular Bone at the Tibia 66% Site	Baseline (initial) measurement of volumetric bone density of trabecular bone at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Volumetric Bone Density of Cortical Bone at the Tibia 66% Site	Baseline (initial) measurement of volumetric bone density of cortical bone at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline
Primary	Baseline Periosteal Circumference at the Tibia 66% Site	Baseline (initial) measurement of periosteal circumference at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline
Primary	Baseline Cortical Thickness at the Tibia 66% Site	Baseline (initial) measurement of cortical thickness at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline
Primary	Baseline Stress-Strain Index at the Tibia 66% Site	Baseline (initial) measurement of strength-strain index at the tibia 66% site. Stress-strain index (also called strength-strain index and stress-strength index in the literature) is a measure of the resistance to torsional and bending forces at diaphyseal sites of long bones. Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: mm^3.	Baseline
Primary	12-month Change in Total Volumetric Bone Density the Femur 4% Site	Baseline to 12-month change in total volumetric bone density at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Volumetric Bone Density of Trabecular Bone at the Femur 4% Site	Baseline to 12-month change in volumetric bone density of trabecular bone at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Volumetric Bone Density of Cortical Bone at the Femur 4% Site	Baseline to 12-month change in volumetric bone density of cortical bone at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Trabecular Bone Area at the Femur 4% Site	Baseline to 12-month change in trabecular bone area at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: square millimeters (mm^2).	Baseline to 12-months
Primary	12-month Change in Cortical Bone Area at the Femur 4% Site	Baseline to 12-month change in cortical bone area at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: square millimeters (mm^2).	Baseline to 12-months
Primary	12-month Change in Periosteal Circumference at the Femur 4% Site	Baseline to 12-month change in periosteal circumference at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 12-months
Primary	12-month Change in Bone Strength Index at the Femur 4% Site	Baseline to 12-month change in bone strength index (BSI) at the femur 4% site. Bone Strength Index (BSI) is a measurement of the resistance to compression forces at the epiphyses of long bones. Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: mm^4.	Baseline to 12-months
Primary	12-month Change in Total Volumetric Bone Density at the Femur 20% Site	Baseline to 12-month change in total volumetric bone density at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Volumetric Bone Density of Trabecular Bone at the Femur 20% Site	Baseline to 12-month change in volumetric bone density of trabecular bone at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Volumetric Bone Density of Cortical Bone at the Femur 20% Site	Baseline to 12-month change in volumetric bone density of cortical bone at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Thickness of Cortical Bone at the Femur 20% Site	Baseline to 12-month change in thickness of cortical bone at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units millimeters (mm).	Baseline to 12-months
Primary	12-month Change in Periosteal Circumference at the Femur 20% Site	Baseline to 12-month change in periosteal circumference at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 12-months
Primary	12-month Change in Stress-Strain Index at the Femur 20% Site	Baseline to 12-month change in strength-strain index at the femur 20% site. Stress-strain index (also called strength-strain index and stress-strength index in the literature) is a measure of the resistance to torsional and bending forces at diaphyseal sites of long bones. Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: mm^3.	Baseline to 12-months
Primary	12-month Change in Total Volumetric Bone Density at the Tibia 4% Site	Baseline to 12-month change in total volumetric bone density at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Volumetric Bone Density of Trabecular Bone at the Tibia 4% Site	Baseline to 12-month change in volumetric bone density of trabecular bone at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Volumetric Bone Density of Cortical Bone at the Tibia 4% Site	Baseline to 12-month change in volumetric bone density of cortical bone at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Trabecular Bone Area at the Tibia 4% Site	Baseline to 12-month change in trabecular bone area at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: square millimeters (mm^2).	Baseline to 12-months
Primary	12-month Change in Cortical Bone Area at the Tibia 4% Site	Baseline to 12-month change in cortical bone area at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: square millimeters (mm^2).	Baseline to 12-months
Primary	12-month Change in Periosteal Circumference at the Tibia 4% Site	Baseline to 12-month change in periosteal circumference at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 12-months
Primary	12-month Change in Bone Strength Index at the Tibia 4% Site	Baseline to 12-month change in bone strength index (BSI) at the tibia 4% site. Bone Strength Index (BSI) is a measurement of the resistance to compression forces at the epiphyses of long bones. Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: mm^4.	Baseline to 12-months
Primary	12-month Change in Total Volumetric Bone Density at the Tibia 50% Site	Baseline to 12-month change in total volumetric bone density at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Volumetric Bone Density of Trabecular Bone at the Tibia 50% Site	Baseline to 12-month change in volumetric bone density of trabecular bone at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Volumetric Bone Density of Cortical Bone at the Tibia 50% Site	Baseline to 12-month change in volumetric bone density of cortical bone at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Periosteal Circumference at the Tibia 50% Site	Baseline to 12-month change in periosteal circumference at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 12-months
Primary	12-month Change in Cortical Thickness at the Tibia 50% Site	Baseline to 12-month change in cortical thickness at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 12-months
Primary	12-month Change in Stress-Strain Index at the Tibia 50% Site	Baseline to 12-month change in strength-strain index at the tibia 50% site. Stress-strain index (also called strength-strain index and stress-strength index in the literature) is a measure of the resistance to torsional and bending forces at diaphyseal sites of long bones. Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: mm^3.	Baseline to 12-months
Primary	12-month Change in Total Volumetric Bone Density at the Tibia 66% Site	Baseline to 12-month change in total volumetric bone density at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Volumetric Bone Density of Trabecular Bone at the Tibia 66% Site	Baseline to 12-month change in volumetric bone density of trabecular bone at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate.Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Volumetric Bone Density of Cortical Bone at the Tibia 66% Site	Baseline to 12-month change in volumetric bone density of cortical bone at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 12-months
Primary	12-month Change in Periosteal Circumference at the Tibia 66% Site	Baseline to 12-month change in periosteal circumference at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 12-months
Primary	12-month Change in Cortical Thickness at the Tibia 66% Site	Baseline to 12-month change in cortical thickness at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 12-months
Primary	12-month Change in Stress-Strain Index at the Tibia 66% Site	Baseline to 12-month change in strength-strain index at the tibia 66% site. Stress-strain index (also called strength-strain index and stress-strength index in the literature) is a measure of the resistance to torsional and bending forces at diaphyseal sites of long bones. Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: mm^3.	Baseline to 12-months
Primary	24-month in Change in Total Volumetric Bone Density the Femur 4% Site	Baseline to 24-month change in total volumetric bone density at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units mg/ccm.	Baseline to 24-months
Primary	24-month in Change in Volumetric Bone Density of Trabecular Bone at the Femur 4% Site	Baseline to 24-month change in volumetric bone density of trabecular bone at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month in Change in Volumetric Bone Density of Cortical Bone at the Femur 4% Site	Baseline to 24-month change in volumetric bone density of cortical bone at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Trabecular Bone Area at the Femur 4% Site	Baseline to 24-month change in trabecular bone area at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: square millimeters (mm^2).	Baseline to 24-months
Primary	24-month Change in Cortical Bone Area at the Femur 4% Site	Baseline to 24-month change in cortical bone area at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: square millimeters (mm^2).	Baseline to 24-months
Primary	24-month Change in Periosteal Circumference at the Femur 4% Site	Baseline to 24-month change in periosteal circumference at the femur 4% site . Measurement made by pQCT at a distance of 4% of total femur length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 24-months
Primary	24-month Change in Bone Strength Index at the Femur 4% Site	Baseline to 24-month change in bone strength index (BSI) at the femur 4% site. Bone Strength Index (BSI) is a measurement of the resistance to compression forces at the epiphyses of long bones. Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: mm^4.	Baseline to 24-months
Primary	24-month Change in Total Volumetric Bone Density at the Femur 20% Site	Baseline to 24-month change in total volumetric bone density at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Volumetric Bone Density of Trabecular Bone at the Femur 20% Site	Baseline to 24-month change in volumetric bone density of trabecular bone at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Volumetric Bone Density of Cortical Bone at the Femur 20% Site	Baseline to 24-month change in volumetric bone density of cortical bone at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Thickness of Cortical Bone at the Femur 20% Site	Baseline to 24-month change in thickness of cortical bone at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 24-months
Primary	24-month Change in Periosteal Circumference at the Femur 20% Site	Baseline to 24-month change in periosteal circumference at the femur 20% site . Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 24-months
Primary	24-month Change in Stress-Strain Index at the Femur 20% Site	Baseline to 24-month change in strength-strain index at the femur 20% site. Stress-strain index (also called strength-strain index and stress-strength index in the literature) is a measure of the resistance to torsional and bending forces at diaphyseal sites of long bones. Measurement made by pQCT at a distance of 20% of total femur length from the distal growth plate. Measurement units: mm^3.	Baseline to 24-months
Primary	24-month Change in Total Volumetric Bone Density at the Tibia 4% Site	Baseline to 24-month change in total volumetric bone density at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Volumetric Bone Density of Trabecular Bone at the Tibia 4% Site	Baseline to 24-month change in volumetric bone density of trabecular bone at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Volumetric Bone Density of Cortical Bone at the Tibia 4% Site	Baseline to 24-month change in volumetric bone density of cortical bone at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Trabecular Bone Area at the Tibia 4% Site	Baseline to 24-month change in trabecular bone area at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: square millimeters (mm^2).	Baseline to 24-months
Primary	24-month Change in Cortical Bone Area at the Tibia 4% Site	Baseline to 24-month change in cortical bone area at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: square millimeters (mm^2).	Baseline to 24-months
Primary	24-month Change in Periosteal Circumference at the Tibia 4% Site	Baseline to 24-month change in periosteal circumference at the tibia 4% site . Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 24-months
Primary	24-month Change in Bone Strength Index at the Tibia 4% Site	Baseline to 24-month change in bone strength index (BSI) at the tibia 4% site. Bone Strength Index (BSI) is a measurement of the resistance to compression forces at the epiphyses of long bones. Measurement made by pQCT at a distance of 4% of total tibia length from the distal growth plate. Measurement units: mm^4.	Baseline to 24-months
Primary	24-month Change in Total Volumetric Bone Density at the Tibia 50% Site	Baseline to 24-month change in total volumetric bone density at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Volumetric Bone Density of Trabecular Bone at the Tibia 50% Site	Baseline to 24-month change in volumetric bone density of trabecular bone at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Volumetric Bone Density of Cortical Bone at the Tibia 50% Site	Baseline to 24-month change in volumetric bone density of cortical bone at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Periosteal Circumference at the Tibia 50% Site	Baseline to 24-month measurement of periosteal circumference at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 24-months
Primary	24-month Change in Cortical Thickness at the Tibia 50% Site	Baseline to 24-month change in cortical thickness at the tibia 50% site . Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 24-months
Primary	24-month Change in Stress-Strain Index at the Tibia 50% Site	Baseline to 24-month change in strength-strain index at the tibia 50% site. Stress-strain index (also called strength-strain index and stress-strength index in the literature) is a measure of the resistance to torsional and bending forces at diaphyseal sites of long bones. Measurement made by pQCT at a distance of 50% of total tibia length from the distal growth plate. Measurement units: mm^3.	Baseline to 24-months
Primary	24-month Change in Total Volumetric Bone Density at the Tibia 66% Site	Baseline to 24-month change in total volumetric bone density at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Volumetric Bone Density of Trabecular Bone at the Tibia 66% Site	Baseline to 24-month change in volumetric bone density of trabecular bone at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Volumetric Bone Density of Cortical Bone at the Tibia 66% Site	Baseline to 24-month change in volumetric bone density of cortical bone at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: milligrams per cubic centimeter (mg/ccm).	Baseline to 24-months
Primary	24-month Change in Periosteal Circumference at the Tibia 66% Site	Baseline to 24-month change in periosteal circumference at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 24-months
Primary	24-month Change in Cortical Thickness at the Tibia 66% Site	Baseline to 24-month change in cortical thickness at the tibia 66% site . Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: millimeters (mm).	Baseline to 24-months
Primary	24-month Change in Stress-Strain Index at the Tibia 66% Site	Baseline to 24-month change in strength-strain index at the tibia 66% site. Stress-strain index (also called strength-strain index and stress-strength index in the literature) is a measure of the resistance to torsional and bending forces at diaphyseal sites of long bones. Measurement made by pQCT at a distance of 66% of total tibia length from the distal growth plate. Measurement units: mm^3.	Baseline to 24-months