Download Poster (384 KB)


Introduction: Aquatic therapy has been used in various patient populations as a modality to facilitate motor control and manage tonicity.1-3 Despite the variety of literature addressing individuals with Down syndrome (DS) and aquatic therapy, there has been little described about the effects of aquatic therapy on early gross motor development in children with DS.

Purpose: The purpose of this case study is to examine whether aquatic physical therapy interventions combined with early start physical therapy influence gross motor developmental delay in a child with DS.

Case Description: The patient is a 31-month-old boy with diagnosis of DS presenting with moderate-severe hypotonia and lengthy medical and surgical history related to complications secondary to his diagnosis. He began receiving early start physical therapy at 4-months-old at a frequency of one in-home session weekly. His Peabody Developmental Motor Scales-2 (PDMS-2) scores at 2 months (T1) and 14 months (T2) of age showed a 50% gross motor delay across all categories, and his 26 month (T3) score showed a 59% gross motor delay across all categories.4 At the time of T3, the patient would not tolerate quadruped positioning and used rolling as his primary method of mobility. He was able to pull himself into kneeling and standing with guarding but would not maintain either position longer than 20 seconds. In order to combat his increasing gross motor delay, warm water therapy sessions were added to the patient’s plan of care at 26-months-old at a frequency of two sessions per month. His physical therapy interventions emphasized core stability and strength, upper and lower extremity weight bearing, and dynamic balance in order to facilitate continued development of gross motor skills. A fourth evaluation, (T4), was performed 5 months following initiation of warm water therapy.

Outcomes: The patient’s PDMS-2 raw score increased by 18 points between T2 and T3, and 16 points between T3 and T4. Minimal Clinically Important Difference (MCID) for PDMS-2 is 8.39, showing significant improvement between both T2 to T3 and T3 to T4. The percent of gross motor delay between T2 and T3 increased by 9%, but remained stable, and increased 2% between T3 and T4. Minimal detectable change (MDC) for change in developmental delay is 8.2%, showing regression between T2 to T3 and stabilization between T3 to T4.4-5 As of T4, the patient tolerates quadruped briefly but prefers tummy crawling for long distances. He can independently pull to stand and initiate cruising steps.

Discussion: Aquatic therapy in a child with DS was associated with improved gross motor abilities and stabilization of gross motor delay over 5 months. While gross motor delay is normal in children with DS, progression of milestones is still expected, and therefore growing gross motor delay can be cause for concern.6-7 This case report supports prior research indicating that aquatic interventions can improve gross motor control.1 The findings suggest that aquatic interventions can be a beneficial modality within Early start physical therapy services to promote gross motor development in this population. The information gained from this case report can be utilized to help guide decision making for practitioners working with children with DS.

Publication Date



San Marcos, CA


Down Syndrome, Gross Motor Disorders, Muscle Hypotonia, Hydrotherapy, Weight Bearing, Postural Balance, Male, Child, Preschool, Physical Therapy Modalities


Pediatrics | Physical Therapy | Rehabilitation and Therapy


Poster presented at the Fall 2019 Research Day on the San Marcos, CA, campus of the University of St. Augustine for Health Sciences, December 13, 2019.


  1. Kucher G, Moore K, Rodia R, Moser CS. Aquatic therapy for children. J Occup Ther, Sch, & Early Intervent. 2015; 8(4):277-291. doi:
  2. Boer PH, DeBeer Z. The effect of aquatic exercises on the physical and functional fitness of adults with Down syndrome: A non-randomised controlled trial. J Intellect Disability Res. 2019; 63(12):1453-1493. Doi: 10.1111/jir.12687
  3. Israel VL. Aquatic physical therapy: The aquatic functional assessment scale (AFAS) in muscular dystrophy. J Aquatic Phys Ther. 2018; 26(1):21-30.
  4. Maring JR, Courcelle-Carger KJ. Comparison of gross motor subtest scores of the Peabody developmental motor scale-2 in children with down syndrome. Pediatric Phys Ther. 2004; 16(1):61-62. doi: 10.1097/01.PEP.0000115221.39160.D5
  5. Wuang YP, Su CY, Huang MH. Psychometric comparisons of three measures for assessing motor functions in preschoolers with intellectual disabilities. J Intellect Disability Res. 2012; 56(6):567-578. doi:10.1111/j.1365-278.2011.01491.x
  6. Winders P, Wolter-Warmerdam K, Hickey F. A schedule of gross motor development for children with Down syndrome. J Intellect Disability Res. 2019; 63(4):346-356. doi: 10.1111/jir.12580.
  7. Pereira K, Basso RP, Lindquist ARR, da Silva LGP, Tudella E. Infants with down syndrome: Percentage and age for acquisition of gross motor skills. Res Dev Disabilities. 2013; 34:894-901.

The Effect of Aquatic Interventions in Combination with Early Start Physical Therapy Services on Gross Motor Development in a Male Child with Down Syndrome