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Self Regulated Physical Activity and Bone Growth Enhancement in Premature Infants

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT03884322
Recruitment Status : Completed
First Posted : March 21, 2019
Last Update Posted : March 21, 2019
Information provided by (Responsible Party):
Barbara Kozol, Asante Health System

Brief Summary:

Premature very low birth weight (VLBW) infants were placed in two groups matched for birth age. The control group received traditional joint compression exercises designed to decrease bone density loss.

Exercises lasted approximately 10 minutes each day 5 days a week. The experimental group were placed in a "prepod", an elastic fabric pod shaped garment or sack on entry into the study and remained in the pod essentially 24 hours a day, with brief breaks for bathing, parental skin to skin experiences,etc. An ultrasound of the left tibia was done on entrance into the study at 31 to 32 weeks gestation and again at completion of the study 4 weeks later. Results showed that experimental infants in pods had slightly less bone density loss than their peers receiving traditional therapy. An incidental finding was that the experimental infants in pods had a significantly shorter length of stay.

Condition or disease Intervention/treatment Phase
Prematurity VLBW - Very Low Birth Weight Infant Other: Prepod Procedure: Joint compression exercises Not Applicable

Detailed Description:

During fetal development the developing babe pushes against the uterine wall, often kicking and punching the unfortunate mother, especially during the last few months of pregnancy. The striking out against the resistance of the uterine wall causes joint compression in the arms, legs, and spine and that sensory feedback triggers bone growth. Unfortunately in the premature infant they are robbed of that exercise opportunity and are either splayed out in an incubator trying to copy with movement against gravity or swaddled so that movement isn't really an option. As a result bone density loss occurs in essentially all premature infants and osteopenia or significant loss can be an issue.

Between 1995 and 2008 there was a good deal of work done on identifying the importance of exercise and movement for premature infants. Moyer-Mileur was the leading researcher in the USA who demonstrated that simple exercise programs could prevent or decrease bone density loss. Although there is a shortage of trained therapists to provide these exercises safely they became a fairly common practice by 2010. At about that time the neonatologists at the Asante facility asked to incorporate the exercises into the NICU therapy program and after appropriate training the exercises began.

The Asante NICU is highly developmentally oriented. Infants grow 150 million brain cells an hour during the last few months of pregnancy. Any of the multiple stressors of prematurity can create cortisol and affect that brain growth. For that reason therapists became concerned with the joint compression exercises. While they were good for bone and muscle health the exercises were not always welcomed by the infant. Even the most gentle compassionate therapist is not always welcome if the infant just wants to sleep or be left alone. Therapists sought a system that could provide the needed exercise but in a manner more developmentally appropriate. It took two years of experimenting with different types of materials and different strengths of elasticity before the Prepod design finally evolved. Then the obvious hypothesis was - Will the Prepod be as effective in decreasing bone density loss as the traditional therapy exercises?? After multiple issues replacing originally planned DEXA measurements with safer UTS measurements, the first subjects were enrolled in 2013. Unfortunately in 2015 an issue with the ultrasound machine was identified; the anti-theft anklets the infants wore emitted signals that had corrupted the data. The study needed to be restarted in 2015, removing the anklets prior to measurement. It then proceeded without incident, with expected completion late 2018. At the IRB (Institutional Review Board) review winter of 2017 the overseeing group concluded that the data for length of stay was so compelling that continuing the study wasn't likely to change anything and basically amounted to withholding care from the traditional exercise infants. They ordered early closure of the study, despite the small number of study participants.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 54 participants
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: Hypothesis: Premature infants placed in elastic fabric "pods" with opportunity to self initiate exercise pushing against fabric would maintain bone density as well as premature infants receiving traditional joint compression exercises by trained therapists
Masking: None (Open Label)
Masking Description: Masking not possible as obvious which child in pod. Infants were instead matched by age and weight to guarantee uniformity of sample
Primary Purpose: Other
Official Title: Self Regulated Physical Activity and Bone Growth Enhancement in Premature Infants
Actual Study Start Date : October 21, 2013
Actual Primary Completion Date : January 25, 2017
Actual Study Completion Date : March 30, 2018

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: Prepod Group
Premature Infants (31 to 32 weeks gestation on entry to program), healthy who wear a prepod or elastic knit fabric pod with snaps essentially 24 hrs a day with brief breaks for bathing, exams, or parent skin to skin time. The intervention lasts 4 weeks
Other: Prepod
the prepod is either a 4 way stretch polyester blend fleece with 8 to 10% lycra, or a 95%cotton5% lycra blend knit. It comes in 4 different sizes to assure a pod that has a conforming but not restricting fit so that the infant is free to stretch in any direction at any time but is loosely held in a position of physiological flexion (the fetal position) when not stretching.

Active Comparator: Control Group
Premature infants (31 to 32 weeks of age on entry to program), healthy who receive a joint compression exercise program approximately 10 minutes a day 5 days a week. The intervention lasts 4 weeks
Procedure: Joint compression exercises
Each premature infant enrolled as a control subject received approximately 10 minutes of joint compression exercises provided by a NICU trained physical or occupational therapist 5x a week. The exercises consisted of waking the infant slowly, gently if necessary just before feeding with a simple range of motion stretching program then stabilizing an extremity and applying force distally to proximally for 6 repetitions with a brief pause between each compression.

Primary Outcome Measures :
  1. Change in bone density [ Time Frame: 27 to 28 days ]

    Infants were divided into two groups - experimental (Prepod) and control (joint compression exercises).

    The infants were measured at 31 to 32 weeks gestation using ultrasound to measure the SOS (speed of sound) through the left tibia at mid point between knee and ankle. They were then remeasured at end of study and the two measurements compared.

  2. Change in length of Stay [ Time Frame: 27 to 28 days ]
    Infants in study were followed to discharge and length of stay from birth to discharge of the two matched groups were compared.

Secondary Outcome Measures :
  1. Change of length of stay of all Prepod candidates [ Time Frame: 27 to 28 days ]
    As mentioned in previous documentation the Prepod study began in 2013 but bone density data from 2013 to 2015 had to be discarded due to issues with UTS data corruption. However the infant experience in the Prepod and exercises were identical to those in the final study so length of stay of the combined population was examined.

Information from the National Library of Medicine

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Ages Eligible for Study:   32 Weeks to 36 Weeks   (Child)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria: 31 to 32 week gestation premature infants AGA (appropriate for gestational age weight) parental consent

Exclusion Criteria: Respiratory disease Low Apgars ( 5 minute less than 4) Syndromes affecting growth SGA (small for gestational age) medication requirements beyond vitamins, iron and caffeine


Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03884322

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United States, Oregon
Rogue Regional Medical Center
Medford, Oregon, United States, 97504
Sponsors and Collaborators
Asante Health System
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Principal Investigator: Barbara Kozol, MS,OTL Barbara Kozol

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Responsible Party: Barbara Kozol, Barbara Kozol,MS, OTL, staff neonatal occupational therapist, Asante Health System Identifier: NCT03884322    
Other Study ID Numbers: AsanteHS
First Posted: March 21, 2019    Key Record Dates
Last Update Posted: March 21, 2019
Last Verified: March 2019
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Plan Description: Infant's names were coded on entry into all data tracking for privacy, HIPAA purposes. Individual data and results were not important (beyond assuring they maintained health) as the researcher was looking at overall trends
Keywords provided by Barbara Kozol, Asante Health System:
physical activity
bone density
length of stay
Additional relevant MeSH terms:
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Premature Birth
Birth Weight
Obstetric Labor, Premature
Obstetric Labor Complications
Pregnancy Complications
Body Weight