Outpatient Physical Therapy for a Toddler with Down

OUTPATIENT PHYSICAL THERAPY FOR A TODDLER WITH DOWN

SYNDROME PRESENTING WITH DEVELOPMENTAL DELAYS

A Doctoral Project A Comprehensive Case Analysis

Presented to the faculty of the Department of Physical Therapy

California State University, Sacramento

Submitted in partial satisfaction of the requirements for the degree of

DOCTOR OF PHYSICAL THERAPY

Sarah E. Christiansen

SUMMER 2015

Sarah E. Christiansen

OUTPATIENT PHYSICAL THERAPY FOR A TODDLER WITH DOWN

SYNDROME PRESENTING WITH DEVELOPMENTAL DELAYS

A Doctoral Project

Sarah E. Christiansen

Approved by:

______, Committee Chair Dr. Katrin Mattern-Baxter

______, First Reader Dr. Bryan Coleman-Salgado

______, Second Reader Dr. Edward Barakatt

______Date

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Student: Sarah E. Christiansen

I certify that this student has met the requirements for format contained in the University format manual, and that this project is suitable for shelving in the Library and credit is to be awarded for the project.

______, Department Chair ______Dr. Edward Barakatt Date

Department of Physical Therapy

Abstract

OUTPATIENT PHYSICAL THERAPY FOR A TODDLER WITH DOWN

SYNDROME PRESENTING WITH DEVELOPMENTAL DELAYS

Sarah E. Christiansen

A pediatric patient with Down Syndrome was seen for outpatient physical therapy treatment provided by a student for ten sessions from February to June 2014 at a university setting under the supervision of a licensed physical therapist.

The patient was evaluated at the initial encounter with Peabody Developmental

Motor Scale-2 and Gross Motor Function Measurement-88 and a plan of care was established. Main goals for the patient were to improve developmental motor functions through increasing functional strength, gait endurance and speed, improving balance, and independent ambulation of stairs. Main interventions used were task-specific, family-centered, and high-intensity approaches. The patient achieved the following goals of increased functional strength, gait endurance and speed, improved balance,

and independent ambulation of stairs. The patient was discharged home to prior living arrangement with mother as primary caregiver.

______, Committee Chair Dr. Katrin Mattern-Baxter

______Date

ACKNOWLEDGEMENTS

To my family, friends, and the faculty of Sacramento State’s Doctoral of Physical

Therapy Program who have helped me throughout the years, giving me support and guidance as I have grown personally and professionally. I would like to especially thank my advisor Dr. Katrin Mattern-Baxter for her guidance throughout the program and mentorship during this project.

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TABLE OF CONTENTS Page

List of Tables ...... ix

Chapter

1. GENERAL BACKGROUND ...... 1

2. CASE BACKGROUND DATA ...... 3

3. EXAMINATION – TESTS AND MEASURES ...... 7

4. EVALUATION ...... 17

5. PLAN OF CARE – GOALS AND INTERVENTIONS ...... 19

6. OUTCOMES ...... 32

7. DISCUSSION ...... 36

References ...... 39

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LIST OF TABLES Tables Page

1. Medications………………………………………….……………………………. 6

2. Examination Data………………………………………..………………………. 15

3. Evaluation and Plan of Care………….………….………………………………. 19

4. Outcomes……………………………….………………..………………………. 32

Chapter 1

General Background

Down Syndrome (DS) is a common chromosomal developmental condition occurring in 6,000 infants, with 1 in 732 infants born in the United States each year.1,2

Down Syndrome is caused by the development of an extra chromosome, resulting in

46 chromosomes. The extra chromosome, typically chromosome 21, also referred to as trisomy, causes the infant’s body and brain to develop abnormally.3 Cytogenetic testing has allowed scientists to further discover the types of chromosome errors that occur: standard trisomsy 21 (most commonly accounting for 95% of DS diagnoses), translocations (accounting for 3% of DS diagnoses), and mosaicism (accounting for

2% of DS diagnoses).2,4 The exact cause for the defect of chromosome 21 failing to split is unknown; it is not due to inheritance and it occurs at random during the formation of reproductive cells.3,5 A majority of research has looked into the maternal nondisjunction errors that lead to trisomy 21 occurrence.2 One of the largest studies that categorized the nondisjunctional errors in DS is the National Down Syndrome

Project. The results from the study have broken down the origin (maternal and paternal) and type of error (meiosis I/II and mitotic) of the extra chromosome 21 based on biological samples: 93.2% of cases from maternal germ cells (oocyte) have chromosome nondisjunction errors occur during meiosis. Of the total meiosis cases of maternal origin, 72.6% occurred during meiosis I. Paternal chromosome nondisjunction errors during meiosis in sperm accounted for 4.1%, however paternal

2 results were limited to a small sample size of 32 biological samples that were received from fathers. Mitotic error was reported at 2.7%.6 Researchers have shown that as a women advances in age and is older than 35 years prior to conceiving a child, there is an increase risk for the child to develop DS. However, the majority of births occur in women under 35 years of age, resulting in ~80% of infants with DS born to younger mothers.7 Down Syndrome is medically diagnosed in a variety of ways. Blood tests and ultrasounds can be performed prenatally for screening. Diagnostic testing for DS is confirmed through amniocentesis, chorionic villus sampling, and percutaneous umbilical blood sampling. After birth, DS is diagnosed through physical signs and confirmed with a blood test.8 Common physical characteristics for DS include a flattened face, almond-shaped eyes slanting up, small ears, short neck, a large furrowed tongue, small hands and feet, poor muscle tone, ligamentous laxity, and short height, among other features.3

Risk factors for development of DS mainly include an increase in maternal age as well as chromosome nondisjunction error.2,3 Researchers have shown that there is a higher prevalence of DS among persons of Hispanic race/ethnicity and in individuals of low social economic status.2,6,9 A study of medical conditions in 208 children with

DS showed that 45.7 % had cardiac conditions (including patent foramen ovale),

59.1% had ear or hearing related conditions, 67.3% had eye or visual related conditions, and 60% had respiratory related conditions with asthma accounting for

20.2%.10

Chapter 2

Case Background Data

Examination – History

The patient who participated in this case study was a 35-month-old male who was diagnosed with DS at birth and presented with developmental delays. The patient was recruited from a treadmill training program. His mother agreed to the case study for physical therapy, with a self-referral, to improve her son’s development. The patient’s previous medical history was reported by his mother, which included having a normal pregnancy and birth. Past medical history included patent foramen ovale, chronic congestion, asthma, myopia, strabismus of left eye and slight auditory deficits.

The mother was unable to provide medical documentation for any of the aforementioned conditions. His mother reported that hearing aids did not help and that the child only wore his glasses for an average of 5 minutes at a time for his myopia. He had surgery in January 2013 for bilateral tube insertions into his ears; the mother reported that the surgery would likely need to be repeated this year. The patient was followed by a team of physicians including a pediatrician, cardiologist, optometrist, and otolaryngologist for his medical care during the course of the treatment period.

The patient’s pediatrician was aware of the patient’s involvement in this case study and noted no precautions or contraindications to physical therapy.

The patient was the second child in the family and had a healthy older brother.

The mother was 33 years old when he was born. The patient had demonstrated

4 significant delay in developmental milestones compared to his peers. The patient had started walking independently within the last 3 months. His mother reported that her chief complaints were that he continued to present with deficits in balance, strength, and inability to ascend/descend stairs.

The patient lived with his mother, father and older brother in a single story house with one entry step into the home from the front entrance, garage, and backyard.

His mother reported that he was able to play and move freely throughout the home without difficultly, which was apparent during a home visit. The patient demonstrated no difficulty ambulating around the house and initiating play in various rooms when toys were within reach. The patient was being potty trained, slept in a crib, and used a car seat in which he required assistance in transfers in/out of the car seat and crib. He also required assistance from an adult when ascending/descending stairs. The patient’s mother was the primary caregiver throughout the day during the time of this case study. When the patient turned three years of age, his mother tried to get him enrolled in school, which would have enabled provision of further physical therapy services.

The neuromuscular and musculoskeletal systems, secondary to neuromuscular involvement, were impaired as demonstrated through testing of range of motion

(ROM), hypotonia (joint laxity), and motor functions. Cognition was also impaired, as reported by mother, and the child was unable to follow complex commands.

Integumentary system was cleared through observation. Other systems, including cardiovascular and pulmonary, were discussed and had been checked and cleared for

5 physical therapy purposes through observation, questioning of the mother, and clearance from pediatrician, who indicated no impairments at the time of treatment.

The physician specialists, mentioned previously, were assessing all other systems in more detail during regular check-ups throughout the case study.

It is important to note that during the episode of care, the patient was sick due to a cold and allergies and could not make 5 of the scheduled treatment sessions; additional treatment sessions were added for a total of 10 treatment sessions. Other reasons he missed the scheduled treatment sessions included a 2-week family vacation, hospitalization for one week due to bronchitis, surgery to correct strabismus on left eye, tube replacement in ears bilaterally, and an auditory brain response test. Due to these events, the treatment sessions were split into two bouts of treatment with 5 sessions completed prior to illness and surgeries, and an additional 5 sessions following the surgeries. The time between initial evaluation and discharge was 5 months.

Examination – Medications

The mother reported that the patient was only taking Pulmicort preventatively for asthma. This medication, also known as budesonide, is a medication that is inhaled to prevent wheezing, shortness of breath, as well as breathing restrictions related to asthma and other lung diseases. The drug belongs to the corticosteroids class.11 The patient remained on this medication throughout the course of this study.

Table 1

Medications

MEDICATION11 DOSAGE REASON PT SIDE EFFECTS Pulmicort 0.5 milligrams 2x a day Preventive for asthma Dizziness, Neck Pain, Stomach, Difficulty falling asleep or staying asleep, Vision problems, Cold or infection that could last a long time, Increased difficultly breathing, or Muscle weakness/ aches.

Chapter 3

Examination- Tests and Measures

Test and measures for Body Structure and Function, Activity, and Participation levels of the ICF model were included in this case study. The test and measures used for Body Structure and Function impairments included range of motion (ROM) measured by goniometry and observation, and the Modified Ashworth Scale (MAS) for muscle tone. Isolated muscle strength testing was not performed due to the inaccuracy of performing manual muscle testing in a child who cognitively could not understand the test nor would maintain the appropriate positions. Instead the patient’s gross strength was measured through completion of functional activities performed in the Gross Motor Function Measure (GMFM-88) and Peabody Developmental Motor

Scale (PDMS-2), which are at the “Activity” level of the ICF model. Additional tests for activity limitations included the 10-meter walk test (10MWT) and the 6-minute walk test (6MWT). Domains from the Pediatric Evaluation of Disability Inventory

(PEDI) were used to assess the patient’s participation restrictions.

A ROM assessment was done using goniometry. Psychometrics, specifically reliability and validity, of ROM as measured by a goniometer vary based on patient population. Passive ROM in general has a number of factors that must be considered: the force given, alignment of the goniometer, and patient population, among other factors.12 Researchers have recommended that a standardization of measuring joints with intra-rater retesting be enforced to reduce the amount of possible error. No

8 psychometrics have been reported on the use of goniometer assessment for ROM in children.

The MAS is a measure used to grade the amount of resistance during velocity- dependent passive range of motion. The measure is graded on a scale ranging from 0-4, with 6 possible options. A score of 0 indicates no resistance or no increase in muscle tone, whereas a score of 4 indicates that the affected joint is rigid in flexion or extension. The test-retest reliability, as measured by interclass correlation coefficients

(ICC), range between 0.21-0.72 for the MAS of the plantar flexors and 0.66-0.80 for the MAS of hamstrings.13 No further psychometrics have been reported on the use of the measure with children at this time.

The PDMS-2 is a diagnostic measure designed to assess gross motor and fine motor skills in children between the ages of birth to 6 years old. The measure is broken into six subscales that each contains a set of items to be assessed for a score on that subscale. The six subscales include the following: Reflexes, Stationary, Locomotion,

Object Manipulation, Grasping, and Visual-Motor Integration. The measure is used as an evaluative and discriminative tool with standardized, normative data provided based on typical developmental stages in aged-matched peers. The PDMS-2 can be used as a diagnostic measure by comparing developmental functions in children with disabilities to children without disabilities who are developing normally. The PDMS-2 can be used to identify motor developmental delays, assess motor development over a period of time, and identify strengths and weaknesses of the child related to motor skills.14 The

9 measure uses a scale of 0 to 2 points for each item listed, with 0 indicating the child did not attempt and 2 indicating the child performed item correctly. Each subscale score can be converted into percentiles and age equivalence. Composite scores can be converted into a sum of standard score, quotient and percentile rank. A higher score, percentile rank, and age equivalence indicates that the child demonstrates higher functional gross motor skills. For this case, the Stationary, Locomotion, and Object

Manipulation subscales, as well as the total gross motor (a composite of these three subscales results) were evaluated. The Stationary subscale includes 30 items that evaluate the child’s ability to maintain center of gravity and equilibrium in a variety of positions. The Locomotion subscale includes 89 items that evaluate the child’s ability to mobilize through various bases of support, such as crawling, walking, running. The

Object Manipulation subscale includes 24 items that evaluate the child’s ability to perform various tasks of throwing, catching, and kicking a ball. The PDMS-2 manual contains psychometrics supporting the reliability and validity of the measure. Average reliability of various age groups ranging from 0-72 months is excellent with an ICC=

0.96 for total gross motor, ICC= 0.89 for Stationary subscale, ICC= 0.96 for

Locomotion subscale, and ICC= 0.90 for Object Manipulation subscale. Standard error of measurement (SEM) for ages 24-35 months is 1 point for Stationary, Locomotion, and Object Manipulation, and 3 points for total gross motor. For age group 36-47,

SEM is 2 points for Stationary, 1 point for Locomotion and Object Manipulation, and 4 points for total gross motor. These values demonstrate a strong reliability in the test

10 results, especially with the smaller SEM values. Strong construct validity, through correlation with age, for the subscales is 0.87 for Stationary, 0.93 for Locomotion, 0.91 for Object Manipulation, and 0.93 for total gross motor.15 The calculated minimal detectable change at a 95% confidence level (MDC95), based on the above SEM is 5.54 for Stationary, 2.77 for Locomotion and Object Manipulation, and 11.09 for total gross motor. In a study looking at the use of the PDMS-2 to assess motor functions in preschoolers with intellectual disability, authors reported the following psychometrics: excellent reliability with an ICC= 0.97, acceptable SEM of 1.80, high concurrent validity of 0.80 through comparison to Bruininks-Oseretsky Test of Motor Proficiency-

Second Edition and Movement Assessment Battery for Children-Second Edition measures, and an MDC95 of 7.76 and minimal clinically important difference of 8.39 at

16 a 95% confidence level (MCID95). No sensitivity or specificity have been reported in literature. This test was used as a diagnostic measure to detect motor developmental delay, as well as an outcome measure to assess change post-intervention.

The GMFM-88 is a prognostic measure that was originally designed to evaluate changes in gross motor function in children with cerebral palsy; however, it has also been validated for persons with DS.17 There are two versions of the test; GMFM-66 is a subset of the items from the GMFM-88 that has been validated and developed specifically for detecting motor developmental changes in the children with CP. The

GMFM-88 has 88 items that allow for a more accurate measure of a child’s current motor abilities and has been proven to be valid for children with DS.18 The GMFM-88

11 contains 5 dimensions to assess motor function that include Lying and Rolling, Sitting,

Kneeling and Crawling, Standing, and Walking, Running, Jumping. Each of the dimensions contains a set of particular tasks. Lying and Rolling (Dimension A) contains tasks such as lifting head in prone, rolling supine to one side, and crossing midline with upper extremities. Sitting (Dimension B) contains tasks such as sitting supported and unsupported, reaching behind, and lowering from higher surfaces to mat. Kneeling and Crawling (Dimension C) contains tasks such as reaching from hands and knees, crawling up/down stairs, and kneeling without support. Standing

(Dimension D) contains tasks such as standing unsupported, single leg stance, high kneeling to standing, and controlled squatting. Walking, Running, Jumping

(Dimension E) contains items such as side stepping, walking forward/ backward, running, jumping, kicking ball, and ambulating on stairs. Each dimension is calculated into a percentage score, with the sum of domain scores averaged to provide a total score of 0-100. A higher score indicates that child demonstrates higher functional gross motor skills. The measure is scored using a 4-point ordinal scale in which 0 indicates unable to perform item and 3 indicating the child is able to fully complete the item. A classification system was also developed to categorize children based on their level of impairment. The system, referred to as The Gross Motor Function Classification

System (GMFCS), was created for children with CP to help standardize the level of severity assigned from medical team members during the testing using the GMFM-88.

There are five levels divided for various age groups. For ages 2-4 years old, the Level

1 classification is for those who are ambulating without assistance yet demonstrate difficulty with advanced motor functions, and the Level 5 classification is for those who have no independent mobilization.19 No classification systems have been established for children with other developmental delays, including DS, at this time.

The GMFM-88 has been validated as a prognostic tool in determining the probability of children with DS achieving motor functions by a certain age.17 Please refer to prognostic considerations section below for further details. Authors of a study that examined the use of the GMFM-88 with children who have DS concluded that the measure was reliable, valid, and responsive to change.20 Excellent interrater and test- retest reliability with ICCs of 0.96 and 0.95, respectively, were reported. Construct validity was demonstrated through correlations between different reporters as well as the different dimensions of the GMFM-88, having stronger correlations when parent reporting was included, improving from 0.40 to 0.59. The authors also reported that the

GMFM-88 had larger changes in scores overall as well as between groups (four groups based on age of under or older than 3 years old and motor impairment level of mild or moderate-severe) when compared to the Bayley Scales of Infant Development- second edition. This demonstrated that the GMFM-88 was responsive to clinically meaningful change with a statistically significant change of 11% between the two examination

20 periods 6 months apart. An MCID95 of 3.8 points and 6.5 points were reported for

GMFM-88 dimensions D and E, respectively, when the measure was used for children with CP in GMFCS level 1.21 Gross motor function growth curves based on GMFM-88

13 score and age to estimate the maximum GMFM-88 score for children with DS was created.17 Results for children with DS began to plateau around the age of 70 months, with the maximum score reported for children who had mild impairments was 87.9% and for children who had moderate or severe impairments the maximum score reported was 85.9%. The authors concluded that on average, children with DS did not achieve all the gross motor functions on the GMFM-88 by the age of 6, suggesting that children with DS require more time to learn complex movements.17 No likelihood ratios have been reported for this measure. The GMFM-88 was used as a prognostic measure to predict possible motor development achievable by the patient’s age and impairment level, as well as an outcome measure to assess global change post- intervention.

The 10MWT was developed as a measure to establish gait speed at two levels: comfortable and fast in healthy adults. No normative data or research has been done on use of the 10MWT in children. Research on the reliability of the fast 10MWT with children who have CP concluded that the measure was not recommended for children

4-18 years of age. Test-retest reliability of ICC 0.81with a large range of 95% CI and

22 an MDC95 of 12.2 seconds were reported in school-aged children. In this case the

10MWT was used as an outcome measure of fast gait velocity.

The 6MWT was used to assess functional walking capacity through distance covered in 6 minutes. There was a lack of studies that examine the reliability of the measure in children with DS. Studies have been conducted that look into normative

14 data for healthy children, reliability and MDC in children with CP, and the reliability of the measure in adolescents and young adults with DS. In healthy male children ages

3-5 years, the average distance was 536.5 meters during the modified 6MWT, in which children were given a measuring wheel adjusted to their height as they walked.23 In children with CP, the test-retest reliability of an ICC was 0.98, with a SEM of 19.8

22 meters, and an MDC95 of 54.9 meters demonstrating high reliability. In adolescents and young adults with DS who had mild intellectual disability a good reliability of an

ICC of 0.80 has been reported, with a calculated SEM of 36 meters and MDC95 of 71 meters.24 The 6MWT was used as an outcome measure.

The PEDI was developed to assess the functional status of self-care, mobility, and social function in children. The functional capabilities are evaluated through either a parent report, direct observation, or testing of function. Psychometrics reported include: good test-retest reliability with a ICC of 0.85 to 0.92, a MCID95 of 10.9 percentage points for Functional Skills scale, and a MCID95 of 11.6 percentage points for Caregiver Assistance scale.25 The PEDI was used as an outcome measure.

Table 2

Examination Data

BODY FUNCTION OR STRUCTURE IMPAIRMENTS Measure Action/ Structure Results Strength N/A Not measured in isolation, however, measured through functional activities. Refer to activity section below. Spasticity Bilateral Lower Score of 0/4. No spasticity found during Measured by: Extremities: examination. Hypotonic in bilateral lower Modified Ashworth hamstrings, extremities. Scale quadriceps, and gastrocnemuis Passive Range of Right: Left: Motion Hip flexion 145º 145º Measured by: Knee flexion 135º 135º Goniometry Dorsiflexion 20º 20º *Ligamentous laxity *Ligamentous laxity noted, within normal noted, within normal range of motion range of motion Active Range of Cervical rotation, Within Functional Limits Motion flexion, and Measured by: extension Clinical Observation Gait Mechanics Base of support and Wide base of support, hip abduction, hyperextension Measured by: Clinical joint laxity of the knees, increased valgus posture of ankle Observation through calcaneal eversion, and toeing out. ACTIVITY LIMITATIONS Measure Domain(s) of Measure Results Interpretation Decreased Gait Speed Fastest speed in meters 0.44 meters per second Patient demonstrated Measured by: per second: Average of or 22.51 seconds slow gait speed with a 10 Meter Walk Test 3 trials wide base of support. Decreased Gait Distance completed 128.6 meters with 4 Patient demonstrated Distance stops impaired gait Measured by: endurance as compared 6 Minute Walk Test to norms for healthy children of 536.5 meters. Decreased Functional Mobility 20/65 points 30.76% Independence in The patient Functional Mobility demonstrated Measured by: significant limitations Pediatric Evaluation in transfers, locomotion of Disability Inventory outdoors, and stair ambulation. Mobility Modification 2/21 points 9.52% (for use of crib and car seat) Developmental Delays in Activities

Lying and Rolling 51/51 points 100% Measured by: No developmental Gross Motor Function delays. Measure-88 Sitting 60/60 points 100% No developmental delays. Crawling and Kneeling 29/42 points 69% Developmental delay in high kneeling. Standing 25/39 points 64% Developmental delay in single leg balance. Walking, Running, 21/72 points 29% Jumping Developmental delays in obstacle clearance, stair ambulation, running, and jumping. Total (raw percentage Raw percentage total: 72.4% totals divided by 5) 362 points Overall, mildly impaired in gross motor skills. Stationary 36/60 points 9th percentile Measured by: Age Equivalence of 11 Peabody months Developmental Motor Locomotion 74/178 points <1st percentile Scale-2 Age Equivalence of 14 months Object Manipulation 13/48 points 5th percentile Age Equivalence of 19 months Total Gross Motor: SS= 14 Patient demonstrated Sum of standard scores Quotient= 66 significant (SS) Percentile rank= 1% developmental delays Quotient and relative compared to typically percentile rank developing children of similar age. PARTICIPATION RESTRICTIONS Measure Domains Results Interpretation Increased dependence Mobility Caregiver 29/35 points 82.85% on caregiver assistance Assistance Significant limitation in Measured by: independence, needing Pediatric Evaluation assistance from mother of Disability Inventory 82% of the time during transfers.

Chapter 4

Evaluation

Evaluation Summary

The patient was a 35-month-old male with DS whose mother reported developmental delays since birth. The patient recently began to ambulate independently at 32-months-old, however, continued to have activity limitations compared to typically developing children his age as measured by the PDMS-2.

Findings of hypotonia, observed cognitive impairment, and delays in developmental gross function were consistent with the medical diagnosis of DS, as provided by physician.

Diagnostic Impression

Patient presented with hypotonia, observed cognitive impairment, and developmental delays consistent with DS, and caused activity limitations in running and ambulation of stairs, as well as participation limitations in independence of caregiver assistance during various tasks.

Physical Therapy Guide Practice Pattern

• 5B: Impaired Neuromotor Development.

• 5C: Impaired Motor Function and Sensory Integrity Associated with

Nonprogressive Disorders of the Central Nervous System- Congenital Origin or

Acquired in Infancy or Childhood.

Current G-Code

• G8978 CK (58%)

The modifier is based on the average age equivalence from the PDMS-2 results divided by the current age in months.

Predicted G-Code

• G8979 CJ (38%)

Chapter 5

Plan of Care- Goals and Inventions

Table 3

Evaluation and Plan of Care

PROBLEM PLAN OF CARE Short Term Goals Long Term Goals Planned Interventions (Anticipated Goals) (Expected Outcomes) Interventions are Direct or 4 weeks 8 weeks Procedural unless they are marked: (C) = Coordination of care intervention (E) = Educational intervention BODY FUNCTION OR STRUCTURE IMPAIRMENTS Abnormal gait No expected change Decrease base of Addressed through red mechanics within 4 weeks support to be more theraband that was placed narrow and decrease around the patient’s legs toeing out during gait and waist to promote internal rotation, knee flexion, toeing in, and hip adduction during gait training interventions described below. (C) Monitor calcaneal valgus angle for potential referral to podiatrist for orthotics. Goals related to functional activities due to the inability to accurately test isolated strength in the patient. Refer to activities section below. ACTIVITY LIMITATIONS Decreased gait No improvements Patient will 15-20 minutes per session speed expected at this time demonstrate an increase was spent on gait training for 10 Meter Walk in fastest gait speed over-ground. Patient wore a Test over the distance of 10 red theraband wrapped meters by 12.2 seconds around bilateral lower to 10.31 seconds extremities and waist to promote internal rotation and adduction to bilateral lower extremities to increase a narrow base of support. In addition to the theraband, 1-pound ankle weights were placed on bilateral lower extremities. Patient ambulated in a

carpeted hall, navigating through doors and around turns. Patient was motivated to keep walking by kicking or high hitting a beach ball that was tied to a stick. Progression of exercise included increasing ankle weights by 0.5 pounds every 2 weeks. A total of 3 pounds per leg was reached. Decreased gait No improvements Patient will improve See above. distance expected at this time gait distance in 6 for 6 Minute Walk Minute Walk Test by Test 54.9 meters to 183.5 meters Decreased No improvements Patient will increase All previous interventions independence in expected at this time independence in will help improve functional mobility for Pediatric functional mobility of functional mobility, Evaluation of Pediatric Evaluation of specifically interventions Disability Inventory Disability Inventory by on gait and stair 10.9 percentage points ambulation. Significant Developmental Delays as measured through Gross Motor Function Measure-88 items and Pediatric Developmental Motor Scale-2 items Improve Standing Dimension of Gross Motor Function Measure-88 by 4 points and Stationary Subscale of Pediatric Developmental Motor Scale-2 by 3 points, by reaching the following goals: Decreased single Patient will improve Patient will improve Single leg activities leg stance on left single leg balance on single leg balance on included: 1) Stepping on a lower extremity left lower extremity to left lower extremity to 5 ½ inch air pump to launch 1-2 seconds > 3 seconds toy rocket into air. Patient initially was given external support from mother to perform task. To increase challenge, the external support was decreased from mother’s hand to a pliable tube to no support. The task was to be completed until fatigue; however, due to the patient’s cognitive impairments it was difficult to achieve more than 10 repetitions per leg in one session. 2) Gait over various size obstacles covered by a mat. Used to enhance single leg stance balance to clear obstacles. Patient would

complete 7 times of walking on mat before losing interest. 3) Single leg stance was also practiced during over- ground gait training through practice of kicking beach ball. Patient would kick the ball on average 8x per leg before losing interest. (E) Mother was taught the importance to improve single leg balance for improving stair ambulation and running advancement. Decreased single Patient will improve Patient will improve See above. leg stance on right single leg balance on single leg balance on lower extremity right lower extremity right lower extremity to 1-2 seconds to > 3 seconds Improve Walking, Running, Jumping Dimension of Gross Motor Function Measure-88 by 8 points and Locomotion Subscale of Peabody Developmental Motor Scale-2 by 6 points, by reaching the following goals: Inability to Patient will take 3 Patient will take > 5 5 minutes per session was ambulate backwards steps backwards with steps backwards spent on practicing to minimal assistance without assistance ambulate backwards from therapist initially with therapist holding at hips to guide the patient backwards. Patient would tolerate 10 steps backwards before trying to turn around. Progression was made through decreasing guidance and use of external support. Patient progressed to use of hula-hoop guided backward stepping for 15 steps, tolerated twice per session. Patient was able to progress with less support from therapist for stabilization of the hula-hoop. Inability to ascend 4 Patient will ascend 4 Patient will ascend 1 Initially patient was stairs (6 inch regular stairs with use flight of regular stairs instructed on stair height) of 1 rail and minimal with use of 1 rail and ambulation with pediatric assistance from no assistance stairs set at different heights therapist (4,6,8,10 inches- 2 inch step clearance required between stairs). Patient

initially given moderate assistance from therapist to ascend stairs, however, progressed through less external support provided. Patient was to complete stairs until fatigued for maximal repetition. On average the patient could ascend the pediatric stairs 6x while holding therapist’s finger. Patient progressed to holding pliable tubing with minimal to contact guard support from therapist while ascending 4 stairs with occasional loss of balance. To progress difficulty of exercise, stair height was increased to 4 inches. Further progression involved ascending stairs that were 6 inches high and 12 stairs per flight. Patient completed on average ascending 2 flights of stairs with progression from holding therapist’s finger to holding rail and pliable tubing with contact support from therapist, to holding rail and pliable tubing with no support. Above exercises that focused on strengthening through gait with ankle weights and single leg balance activities also provided the necessary strength and balance for stair ambulation. Inability to descend Patient will descend 4 Patient will descend 1 See above. 4 stairs (6 inch regular stairs with use flight of regular stairs Descending stairs was height) of 1 rail and minimal with use of 1 rail and progressed from pediatric assistance from no assistance stairs to regular stairs as therapist well. Patient initially needed moderate support of two-finger hold from therapist. Patient was able to progress to one finger hold to rail with minimal

assist for pliable tubing to contact guard support from therapist. PARTICIPATION RESTRICTIONS Increased No improvement Increase independence All previous interventions dependence on expected at this time from caregiver will help improve caregiver assistance for Pediatric assistance by 11.6 independence from for mobility Evaluation of percentage points caregiver assistance. Disability Inventory HOME EXERCISE PROGRAM Mother does not Mother independent in Mother understands (E) Mother instructed on implement a Home implementing Home importance of how to perform exercises Exercise Program Exercise Program continuing Home below. Exercise Program and how to progress Balance: on un-even exercises surfaces for 1 minute x3 as often as possible. Practice single leg stance when getting dressed/undressed.

Strengthening: through balance exercises and stair ambulation at local park x3 days per week. Tricycle practice as often as possible to increase bilateral lower extremity and core strength.

Prognostic Considerations

A study by Trotsenburg et al examined the influence of comorbidity, hospitalization, and medication use on mental and motor development in infants with

DS. The results indicate that children with DS who had the following within the first two years of life demonstrated significantly greater motor developmental delays; recurrent lung/airway disease or admission to a hospital for >11 days.26 Based on these factors, the patient had an increase risk for developmental delay because of a history of asthma and recent hospitalization due to bronchitis. Palisano et al. developed growth curves and probability of walking, running, ascending 2 stairs, and jumping forward in children with DS. The growth curves were interpreted and the authors concluded that the maximum score for children with mild impairments was 85.9% on the GMFM-88.

The predicted GMFM-88 score for children with DS with mild impairments at 3 years old, was reported to be 75.2%, which is the age of the patient in this study. For walking, the probability went from 40% at 24 months, to 74% at 30 months, and 92% at 36 months. The probability of children with DS being able to run 15 ft (including stopping and returning), climbing 2 stairs without support, and jumping forward with 2 feet simultaneously, ranged from 18-25% by 4 years old, to 45-52% by 5 years old, and by 6 years of age the probability increased to 67-84%.17 Based on these results, the patient was unlikely to achieve higher motor developmental skills such as running, climbing 2 stairs, and jumping before the age of 4 years old. Overall, based on the patient’s history of asthma, medication use, recent hospitalization for one week, and

25 current age, the prognosis of achieving significant changes in complex motor functions during this period of care was poor to moderate.

Anticipated discharge setting was home to prior living arrangement with mother as primary caregiver at the completion of this case study.

Plan of Care- Interventions

See Table 3.

Overall Approach

The interventions during the episode of care included 10 one-hour treatment sessions that focused on task-specific, family-centered, high-intensity approaches to improve specific gross motor functions.

Task-specific training was focused on treating activity limitations that the individual demonstrated. The effects of functional training have been shown primarily in children with cerebral palsy compared to Neurodevelopmental Treatment (NDT) methods. Although no between group difference were found in gross motor functions, the group who received functional training improved their functional daily tasks.27

A family-centered practice that focused on the family’s impact on the child’s life and involving the family during treatment was used. The effectiveness of family- centered care in early intervention has been proven to improve a child’s developmental function, family’s understanding of the child’s condition, improve psychosocial welling being of both the child and mother, and other positive outcomes. Family- centered programs that include education to the parents, as well as work on motor

26 behavior at the limit of the child’s capability have all been shown to have positive effects on developmental outcomes.28 The mother of the patient was involved in the plan of care and each treatment session to motivate the child.

Lastly, my treatment approach utilized high-intensity practice that focused on the overload principle through high repetition of an exercise to influence the central nervous system (CNS). Authors of high intensity intervention studies on development of walking through use of treadmill training have shown improvements in earlier onset of walking as well as other locomotor milestones. This is hypothesized to be due to neuroplastic changes induced by treadmill training.29 To influence neuroplastic changes in the CNS, high repetitions for all exercises during each session was implemented during the case study. The patient’s mother was also instructed on how to perform the exercises at home to further encourage more repetitions of each exercise outside of treatment.

PICO question

For a 35-month-old male child with DS (P) is treadmill training (I) more effective than over-ground gait training (C) at increasing gait speed (O)?

Most research on treadmill training versus over-ground gait training is centered on children with CP. There is research on treadmill training in the use of pre- ambulatory children with DS to improve gait onset and motor function development.

Ulrich et al. has researched the effects of treadmill training in pre-ambulatory infants with DS for developmental outcomes and independent stepping onset.29,30 Results from

27 these studies concluded that the infants involved in treadmill training, regardless of intensity, demonstrated improvements in developmental milestones and an earlier onset of walking.29 The patient was already independently walking by the start of this case study, and had been involved in a treadmill training program prior to the treatment period, which could have helped his independence in ambulation. Due to these reasons and lack of research on treadmill versus over-ground training in ambulatory children with DS on increasing gait speed, two studies are reviewed below to address the PICO question that look at children with CP who were of similar age and functional level as my patient. Although CP and DS are inherently different in etiology, both present with damage or abnormalities in the CNS that lead to developmental delay. Treatment approaches for the resulting motor impairments have been more widely studied in CP, but are used across other pediatric diagnoses, including DS. Therefore, I am confident that the research on children with CP can translate to my patient with DS.

The first article reports on a randomized controlled trial (Level of Evidence: 1b;

PEDro Score: 7/10).31 In this study, the focus was on the efficacy of partial body weight treadmill training compared to over-ground walking in children with CP. There were 12 participants in the experimental group (treadmill training) and 14 participants in the control group (over-ground training), aged 5-18 years old with CP and GMFCS level III or IV. Of the 18 sessions, each group completed between 10-17 sessions. The overall results of the study showed no significant difference between groups for increase in 10MWT and deterioration in distance walked in 10 minutes for the

28 experimental group. Although not statistically significant, the control group demonstrated an increase in distance walked in 10 minutes. The overall conclusion of the study is that improvements made in treadmill training may not directly carryover to over-ground training. A limitation to applying this study is that the patient would not have been included in the study sample because of different diagnosis, younger age and was at a higher functioning level. It is, however, one of the most applicable investigations to the patient described in this case study. Due to these factors, I am only moderately confident that over-ground walking will provide similar outcomes for the patient in this study.

The second article reports on a randomized controlled clinical trial (Level of

Evidence: 1b; PEDro Score: 8/10).32 This study compared the effects of treadmill training to over-ground training in 36 participants with CP between the ages of 3-12 with GMFCS levels of I, II or III. The experimental group consisted of 16 participants and the over-ground walking group consisted of 17 participants. Both groups improved significantly on the 6 minute walk test and demonstrated improvement on the Timed

Up and Go Test, PEDI (mobility domain), GMFM-88 (D and E dimensions), Berg

Balance Scale and time and velocity tolerated on the effort test. The treadmill group did demonstrate better overall results, however both groups showed improvement post- treatment. A limitation to the applicability to my patient to this study was that the study included children with CP, otherwise, the patient in this case study would have been included based on age and functioning level.

Interventions that changed during the course of the study included those that were specific to balance, gait speed, and jumping. An intervention that focused on improving balance was walking on locked roller skates. The skates provided elevated walking surface, weight to enhance strength, and promote single leg stance by advancing each leg. The patient took an average of 5 steps with skates strapped on each foot, and then fell with no attempt to stand back upright without support. This intervention was attempted during 2 sessions, but due to lack of improvement and patient’s apparent dislike of the skates led to the discontinuation of this intervention, and instead we focused more directly on single leg stepping exercises. Improving balance and gait speed was attempted through play while using a parachute. The patient would help the therapist and mother lift the parachute off the ground above his head to work on balance. Once the parachute was in the air, the patient was instructed to run under the parachute to the opposite side as the therapist and mother brought the parachute back to the ground. This intervention was saved for the end of each session because of the patient’s inability to perform other activities after due to distraction and inability to refocus even after the parachute was taken away. The intervention was only performed 3 times during the study due to time constraints. Treadmill training was also attempted 3 times to improve gait speed. Patient was unable to complete more than 5 minutes on treadmill before stopping and refusing to continue. Therefore gait distance and speed were utilized through over-ground gait training with progression of ankle weights to increase difficulty. Finally, interventions related to developing jumping

30 motor function to improve gross motor functions were discontinued during the study.

Interventions for jumping included jumping off top and bottom steps of pediatric stairs and hopping along lily pads placed one foot apart on floor. Patient did not initiate jumping from pediatric stairs without external support by holding on to therapist’s hands, nor initiate jumping on lily pads, instead ran across them. Due to uncertainty of the number of treatment sessions after the hospitalization, the above interventions described were also stopped to focus on specific tasks of balance, gait, and stair ambulation with interventions that had led to the progression of each task.

Indirect interventions included a home exercise program and monitoring of calcaneal valgus angle through clinical observation for possible referral for custom orthotics. If valgus angle of ankles had increased during the study and appeared to impair functional mobility, patient would have been referred to an orthotist or podiatrist for possible orthotic assessment and ordering. A referral for orthotics was not needed during the study because the patient did not show an increase in valgus angle of bilateral ankles (calcaneal eversion) nor have limitations in mobility due to ankle laxity. Looper et al, researched the use of orthotics on gait in children with DS. The results of the study led researches to conclude that children who wore supramalleolar orthoses demonstrated a deceased cadence and increased cycle time compared to barefoot walking. Off-the-shelf foot orthoses had no statistical difference compared to the barefoot walking condition.33 The home exercise program, mentioned above, was

31 explained to the mother that included specific exercises to increase the amount of repetitions and exposure to the task.

Chapter 6

Outcomes

Table 4

Outcomes

OUTCOMES BODY FUNCTION OR STRUCTURE IMPAIRMENTS Outcome Initial Follow-up Change Goal Met (Y/N) Clinical Wide base of support, Narrower base of Minor change N Observation of gait hyperextension of knees, support but not a large in base of mechanics toeing out, and calcaneal difference, no change support and eversion in hyperextension of toeing out knees, slight change in toeing out, and no change in calcaneal eversion

Outcomes assessed through functional activities. Refer to activities section below. ACTIVITY LIMITATIONS Outcome Initial Follow-up Change Goal Met (Y/N) 10 Meter Walk Test 0.44 m/s or 22.51 1.41 m/s or 7.10 Increase in Y seconds seconds speed of 0.65 m/s and a decrease in 15.41 seconds

(MDC95 of 12.2 seconds) 6 Minute Walk Test 128.6 meters with 4 197.2 meters with 2 + 77.7 meters Y stops stops with 2 less stops

(MDC95 of 54.9 meters) Pediatric Evaluation Functional Mobility: 20 27 points (41.5%) 7 points (+10.7 N of Disability points (30.76%) percentage Inventory functional points) mobility subscore

(MCID95 of 10.9 percentage points) Mobility Modification: 2 2 points (9.52%) No change N points (9.52%) Developmental Delays Gross Motor Lying and Rolling: Lying and Rolling: No change N/A Function Measure- 51 points (100%) 51 points (100%) possible 88 Sitting: Sitting: No change N/A 60 points (100%) 60 points (100%) possible

Crawling and Kneeling: Crawling and + 3 points N 29 points (69%) Kneeling: 32 points (+7%) (76%)

Standing: Standing: + 6 points Y 25 points (64%) 31 points (79%) (+15%)

(MCID95 of 3.8 points) Walking, Running, Walking, Running, + 17 points Y Jumping: 21 points Jumping: 38 points (+25%) (29%) (54%) (MCID95 of 6.5 points) Total: 72.4% Total: 81.8% + 9.4% N

(Statistical significance of 11%) Peabody Stationary: 36 points, 9th Stationary: 40 points, Points: +4 N th Developmental percentile, 11 month age 25 percentile, 28 (MDC95 of 5.54 Motor Scale-2 equivalence month age points) equivalence Percentile: Improvement by 16 percentiles. Age Equivalence: +17 months Locomotion: 74 points, Locomotion: 85 Points: +11 Y st st < 1 percentile, 14 points, < 1 percentile, (MDC95 of 2.77 month age equivalence 17 month age points) equivalence Percentile: no change. Age Equivalence:

+3 months Object Manipulation: 13 Object Manipulation: Points: +5 Y th th points, 5 percentile, 19 18 points, 5 (MDC95 of 2.77 month age equivalence percentile, 23 month points) age equivalence Percentile: no change. Age Equivalence: +4 months Total Gross Motor: SS= 15 SS= +1 N Sum of standard scores Quotient= 68 Quotient= +2 (SS)= 14 Percentile rank= 1% Percentile Quotient= 66 Percentile rank= no rank= 1% change

(MDC95 of 11.09 points) Specific Tasks from Single leg stance on left Left lower extremity: + 4 Seconds Y Gross Motor lower extremity: 0 4 seconds Function Measure- seconds 88 and Peabody Single leg stance on Right lower extremity: + 4 Seconds Y Developmental right lower extremity: 0 4 seconds Motor Scale-2 that seconds helped to improve Walking backwards: 0 5 steps taken walking + 5 steps Y total steps backwards score of both Unable to ascend 6 inch Ascend 1 flight of + ascend 1 Y measures stairs stairs with rail flight of stairs with use of rail Unable to descend 6 Descend 1 flight of + descend 1 Y inch stairs stairs with rail. Loss of flight of stairs balance occurred more with use of rail. often during descending compared to ascending of stairs. PARTICIPATION RESTRICTIONS Outcome Initial Follow-up Change Goal Met (Y/N) Pediatric Evaluation Mobility Caregiver 30 points (85.7%) 1 point (+2.85 N of Disability Assistance: 29 points percentage Inventory (82.85%) points)

(MCID95 of 11.6 percentage points) m/s: meters per second MDC95: minimal detectable change MCID95: minimal clinically important difference

Discharge Statement

The patient attended one-hour treatment sessions once a week for a total of 10 visits. Due to illness and other medical complications that occurred, the total visits were divided into two bouts of 5 treatment sessions. The patient presented with increased developmental delays compared to typically developing children of his age.

Patient received task-specific exercises to accomplish the goals selected by his mother.

He was able to progress towards the goals during the course of care, showing improvements in developmental motor functions. The patient was discharged from physical therapy with his mother independent in implanting the home exercise program and instructions on proper ways to progress the given exercises. Patient was discharged home to prior living arrangement with mother as primary caregiver.

Discharge G-Code

• G8980 CK (41%)

The modifier is based on the average age equivalence from the PDMS-2 results divided by the current age in months.

Chapter 7

Discussion

The patient was able to show progress in developmental milestones over the course of the study. Further recommendations for managing this patient or other children with DS who present with developmental delays include simple instructions, repetitive task-specific interventions, and understanding that children with DS take longer to improve developmental motor functions. The patient in this study responded accordingly and as expected to the treatment provided, by improving in his overall motor developmental functions. There were unexpected events that occurred during the study that caused sessions to be missed due to illness, family vacation, and surgery to his eyes and ears. Due to these events, the episode of care was delivered in two bouts of 5 treatments each. Although these events could not be prevented, next time therapy is interrupted for > 2 weeks, I would make sure the mother understands the importance of adhering to interventions and maintaining home exercise program consistency.

There was also the possibility that maturation occurred during this time, and over the period in which the patient was not receiving interventions. This is important to note because the results found in this case cannot be directly interpreted as a success from this treatment plan solely. I used the best evidence to base my intervention program on to provide the patient quality care that was proven to increase developmental motor functions in children with developmental delays. Task-specific training proved beneficial for this patient, even with little variation in the activities. The consistent

37 order of activities and an environment that decreased the patient’s distraction during the sessions was shown to be beneficial by an improved amount of repetitions during each activity. The patient did lose interest with high repetitions of each exercise. In this case I would switch to another exercise and then return to the pervious exercise near the end of the session to increase the amount of repetitions performed during each meeting. I instructed the mother on how to perform similar exercises at home during daily tasks to increase the repetition amount of each exercise. I should have pushed the patient further in completing exercises during the sessions and followed up with the mother on exactly how many repetitions he was performing at home with a journal. I also would have assessed the patient’s functional mobility with outcome measures more thoroughly with use of the Functional Mobility Scale. It would be helpful to have had access to a gait lab or sensor treadmill to accurately assess the patient’s gait mechanics with instrumented measurements that could be compared pre- and post- treatment. The patient presented with typical developmental delays consistent with DS.

I used the best tests and measures that were available at the time and had been validated for the use in the pediatric population to assess developmental delays. These test and measures would be appropriate to use with other patients of a similar diagnosis. There were measures used in this study that have not been validated in the pediatric population, such as the 10MWT for gait speed. Since this is the only test known of for measuring gait speed, it was used to assess any change in speed. The patient was able to improve his total time to complete the test by an increase of 0.65

38 m/s in speed. This improvement was considered a meaningful change to the mother, as one of her goals was to see her son improve gait speed to get closer to running.

The overall approach for the interventions utilized in this case study could be applied to other children with developmental delays, tailoring the specific tasks to meet the needs of the individual patient. A lot of the research used to develop the interventions utilized in this study was performed on children with CP due to the lack of research that has been conducted on independent ambulatory children with DS. The patient demonstrated improvement in his developmental motor functions with the interventions performed in this episode of care. Better research on interventions that accelerate development of motor functions in persons with DS would have been helpful to be more confident in the interventions performed and may have improved the patient’s outcomes even further.

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