DME

Blog posts of '2020' 'April'

Could your child benefit from the Explorer Mini ? Part 1 

  


Welcome to Part 7 of our series about developmental milestones in early childhood focusing on mobility! Read our previous blog entries below.


The Explorer Mini is designed to be used by a wide variety of young children with mobility impairments. Children with physical disabilities who have difficulty achieving independent motor control are often deprived of opportunities for self-initiated or self-produced mobility. Mobility impaired toddlers who cannot move across a room to reach out and touch an object or interact with a person are at a great disadvantage.

They can’t experience the sensorimotor and developmental activities of their peers who have achieved upright mobility, such as pushing and pulling toys, opening and closing drawers, or moving around and under objects.

Self-initiated mobility also affects motor functioning and the ability to develop mature grasp and postural control. Researchers who have studied the impact of early exploration on a child’s development have also suggested that self-produced locomotion and active choice are important for the development of perception and cognition (1).

Because self-produced, self-initiated mobility is intertwined—skills in concert with visual, cognitive, psychosocial, language and coordination—it is not possible to state that there is any pre-requisite skill that would predict a young child’s readiness to be successful or ready for the training in use of the Explorer Mini or any other power mobility device (PMD). 


We can only look at typical developmental patterns and skills and suggest that the skills necessary for joystick interaction are a stable base of support, either by means of postural control or an external postural control seating surface. The joystick interaction is the means by which the device is designed to move. The child’s response to movement will prompt interaction with the device and with the act of mobility. It is the response to movement that contributes to the related aspects of language, postural response, and cognitive skills. 

Therefore, the skill set necessary to engage in self-initiated mobility by means of the Explorer Mini have not been established as no device has allowed us to investigate this.

Our best understanding is predicated on the work of conceptual thinkers and researchers who have demonstrated that mobility prompts the sensorimotor system to respond to the enhanced environmental exploration. Indeed, we know when a child is immobile for a period of time they lapse into a state of “visual idle”, wherein the visual system not being stimulated fails to orient or respond to the all too familiar and non-novel environment (8).

Regarding the gross and fine motor skills necessary for safe use of the EM, we would highlight that these skills are developed as a result of mobility and not foundational skills that are necessary for interacting/ interfacing with the joystick or the movement of the device. To suggest that there are pre-requisites skills necessary to operate the EM would be presumptuous until such a device is available for clinical testing and ongoing use by children with mobility impairments.

Evaluation of children has traditionally focused on the achievement of developmental milestones. Underlying impairments such as motor control deficits cannot fully explain the extent and form of functional difficulties seen in children with disabilities. The tasks that are most relevant for daily independence in mobility function have not been well defined in traditional developmental milestone tests (10).

We do have reliable and valid tools to assess posture of the infant (8). But as noted above, posture or motor skills alone does not predict the infant’s ability to activate a joystick and begin the cascade of development that one would see in an infant capable of self-produced mobility.


If there are no pre-requisites, how can I know if it’s appropriate?

In light of the fact that there are no developmental tests that can predict a young child’s ability to operate the Explorer Mini, it’s important to understand that this does not negate the value of trialling a child in the device. Of the 34 children under the age of 36 months who participated in human factor validation studies of the Explorer Mini, 94% were able to move the device using the midline joystick control while 88% demonstrated cause and effect learning through grasping and releasing the joystick.

Keep in mind, developing children typically don’t learn to sit unsupported or crawl without struggling through some initial failures to reach success. The same is true with the Explorer Mini. The key is to allow young children to try, and even struggle a bit to experience the success of self-initiated movement. 


1. Acredolo, L.P., Adams, A., & Goddwyn, SW., (1984) The role of self-produced movement and visual tracking in infant spatial orientation. Journal of Experimental Psychology, 38, 312-327. Doi: 10.1016/0022-0965(84)90128-0

2. Anderson, D. I., Campos, J. J., Witherington, D. C., Dahl, A., Rivera, M., He, M.,… Barbu-Roth, M. (2013). The role of locomotion in psychologicaldevelopment. Frontiers in Psychology, 4(July), 440. https://doi.org/10.3389/fpsyg.2013.00440

3. Armstrong, W., Borg, J., Krizack, M., Lindsley, A., Mines, K., Pearlman, J., . . . Sheldon, S. (2008). Guidelines on the provision of manual wheelchairs in less resourced settings. Geneva, Switzerland: World Health Organization, WHO Press.

4. Butler, P. (1988). High tech tots: Technology for mobility, manipulation, communication, and learning in early childhood.Technology, Infants Young Children, 1, 66-73

5. Butler, P.B. (1998) A preliminary report on the effectiveness of trunk targeting in achieving independent sitting balance in children with cerebral palsy. Clinical Rehabilitation, 12, 281-293.

6. Butler C, Okamoto G and McKay T. Powered mobility for very young disabled children. Dev Med Child Neurology. 1983;25(4):472–474.

7. Butler C, Okamoto G and McKay T. Motorized wheelchair driving by disabled children. Arch Phys Med Rehabilitation 1984;65(2):95–97.

8. Higgins, C. I., Campos, J. J., and Kermoian, R. (1996). Effect of self-produced locomotion on infant postural compensation to optic flow. Dev. Psychol. 32, 836–841. doi: 10.1037/0012-1649.32.5.836

9. Lynch A, Ryu J, Agrawal S, Galloway JC. (2009) Power mobility training for a 7-month-old infant with spina bifida. Pediatric Physical Therapy.;21:362–368.

10. Mancini, M. C., Coster, W. J., Trombly, C. a, & Heeren, T. C. (2000). Predicting elementary school participation in children with disabilities. Archives of Physical Medicine and Rehabilitation, 81(3), 339–347. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/10724080

11. Paulsson K Christofferson M – 1986 – Psychosocial aspects of technical aids How does independent mobility affect the psychosocial and intellectual development of children with physical disabilities. pdf.

12. Ragonesi CB, Chen X, Agrawal S, Galloway JC. Power mobility and socialization in preschool: a case study of a child with cerebral palsy. Pediatric Physical Therapy. 2010; 22:322–329.

13. Stanton, D., Wilson, P.N., and Foreman, N. (2002). Effects of early mobility on shortcut performance in a simulated maze. Behavior Brain,136, 61-66. doi:10.1016/SO166-4328 (02)00097-9

14. World Health Organization. (2001) The ICF: An overview. Retrieved from https://www.wcpt.org/sites/wcpt.org/files/files/GH-ICF_overview_FINAL_for_WHO.pdf

15. Weisz JR (1979) Perceived control and learned helplessness among mentally retarded and nonretarded children: a developmental analysis. Developmental Psychology 15(3): 311–9470

Dr Teresa Plummer, PhD, OTR/L, ATP, CEAS, CAPS

Associate Professor in the School of Occupational Therapy at Belmont University 

Dr Teresa Plummer, PhD, OTR/L, ATP, CEAS, CAPS is an Associate Professor in the School of Occupational Therapy at Belmont University in Nashville, TN. She has over 40 yrs of OT experience and 20 in the area of Assistive Technology. 

Dr Teresa is a member of the International Society of Wheelchair  Providers, and the Clinicians Task Force. She is a reviewer for American Journal of OT and guest reviewer for many other journals. She has presented internationally, nationally and regionally particularly in the area of pediatric power mobility. She has authored journal articles and textbook chapters in the area of OT and pediatric mobility and access.

Why is freedom of movement important in early childhood development?

 

   


Welcome to Part 6 in our series about developmental milestones in early childhood focusing on mobility. Be sure to read our previous entries below in case you missed them! 


Proximal stability creates distal stability and mobility

The development of posture begins in utero. As the fetus moves against the uterine wall and encounters resistance and moves through amniotic fluid against gravity, muscle strength and tone develop. The baby finds a sense of self and stability due to proprioceptive input. Proprioceptive input is the pressure to the joints, muscles, and connective tissues that tells us where our body is in space, and this is happening even in the womb.

Fetal movement is spontaneously generated and modifiable based on environmental stimuli. Gibson (1988) uses the term “perception-action” supporting the concept that sensory input elicits motor output in a continual cycle rather than a start stop action. Sensory information, movement variability, and postural control are structural and occur during gestation, after birth and throughout the life span.


Why movement is important

Proprioception is the sense that tells us where the body is in space. Proprioceptive input is a sensation at a joint, muscle or connective tissue that is obtained by weight-bearing, lifting, pushing, or pulling objects. When a child is unable to independently move, this proprioception is impacted which can affect body awareness, self-regulation, posture, and coordination to name a few. This is why the position or posture that we put a young child in is so important. We want to promote postures that will provide proprioceptive input at the joints and allow movement to provide stimuli that will trigger muscle function. It’s important to note that providing static or constant stimuli such as constant pressure to a joint capsule results in adaptation. This means the mechanoreceptors embedded in ligaments and joints adapt to a constant stimulus and stop transmitting information about that joint and muscles will not be activated. 

This is one reason movement should not be limited by excessive or undue restraints

Most early mobility devices include postural supports such as pelvic belts, chest harnesses, head supports. These make sense for a full-time mobility device, to provide appropriate support to facilitate an upright and functional posture. But the Explorer Mini was designed with another objective in mind. This device is not meant to be used full time and was designed to promote developmental milestones through movement—not only movement of the device, but movement of an unrestricted yet safely supported posture.

What does this look like?

You can see below when Davis was first placed in the device he was severely leaning but was not in danger of falling due to the inherent support of the tray and back. The temptation was to “fix” his posture right away and not watch him struggle. Yet we are used to watching typically developing children struggle through their milestones with crawling, sitting, standing, and walking. We watched Davis struggle and he was persistent and moved himself into an upright seated posture where he could eventually have success achieving midline in the device! 

The Explorer Mini was designed to promote proprioceptive input to the upper extremities with the tray and joystick, and to the lower extremities with the saddle seat and adjustable seat height.

Upper Extremity Weight-Bearing: Weight-bearing through the forearms and hands contributes to weight-bearing at the shoulder joint which translates stability into the upper trunk leading to greater control of the upper trunk and head. This synergistic (combined ) weight-bearing aids in the development of oculomotor stability and vestibular stimuli.

Lower Extremity Weight-Bearing: The saddle seat specifically promotes proprioceptive input and hip development by positioning hips in abduction with lower extremity weight-bearing. The seat height can be adjusted to alter joint angles and encourage forward weight shift. Additionally, the shape of the saddle seat coupled with the tray for upper extremity weight-bearing bring the pelvis into an anterior pelvic tilt which encourages trunk extension.

There are intentionally no postural restraints on the Explorer Mini to allow movement and proprioceptive input to the joints and encourage muscle activation. 

The body needs frequent opportunities to move around a stable surface, that being the pelvis and/or lower body support. One consideration in using a device like the Explorer Mini is to alter the positions and height of the tray and seat support to provide a variety of joint angles and maximise proprioceptive input.  

The following picture depicts how the table and seat surface of the Explorer Mini facilitates postural support through the multiple weight-bearing surfaces. 

Remember, the Explorer Mini is not intended to be a child’s full-time device. It is meant to be a tool that will promotes self-initiated mobility and allow freedom of movement to develop trunk extension and stability, head control, and functional use of the upper extremities.  


1. Hagert, E., Persson, J., Werner, M., & Ljung, B-O. (2009). Evidence of wrist proprioceptive reflexes elicited after stimulation of the scapholunate interosseous ligament. American Society for Surgery of the Hand, 34A. 642-651.

2. Henderson, A., & Pehoski, C., (2006). Hand Functions in the Child: Foundations for Remediation, 2nd edition. Mosby, Elsevier. St. Louis, Missouri.

3. Michelson, JD, & Hutchins, C., (1995), Mechanoreceptors in human ankle ligaments. The Journal of Bone and Joint Surgery. British vol. 77-B

4. Rosenblum, S., & Josman, N. (2003). The relationship between postural control and fine manual          dexterity. Physical and Occupational Therapy in Pediatrics, 23,(4). 47-60.

5. Stavness, C., (2006). The effect of positioning for children with Cerebral Palsy on upper-extremity      function: A review of the evidence. PT and OT in Pediatrics, 26,39-52

6. Westcott, S., & Burtner, P. (2004). Postural control in children: Implications for pediatric practice. PT and OT in Pediatrics, 24, 5-55.

7. Scheiman, M. (2011). Understanding and managing vision deficits: A guide for occupational                therapists. Thorofare, NJ: SLACK Incorporated. 


 

Dr Teresa Plummer, PhD, OTR/L, ATP, CEAS, CAPS

Associate Professor in the School of Occupational Therapy at Belmont University

Dr Teresa Plummer, PhD, OTR/L, ATP, CEAS, CAPS is an Associate Professor in the School of Occupational Therapy at Belmont University in Nashville, TN. She has over 40 yrs of OT experience and 20 in the area of Assistive Technology.

She is a member of the International Society of Wheelchair Providers, and the Clinicians Task Force. She is a reviewer for American Journal of OT and guest reviewer for many other journals. She has authored journal articles and textbook chapters in the area of OT and pediatric mobility and access.

Fostering Independence for Children with Limited Mobility

 

  


Welcome to Part 5 in our series about developmental milestones in early childhood focusing on mobility. 


“When development along any line is restricted, delayed, or distorted, other lines of development are adversely affected as well.” (1)

Restricted experiences and mobility during early childhood can have a diffuse and lasting influence. Long term physical restrictions during infancy or early childhood can significantly alter and disrupt the entire subsequent course of emotional or psychological development in the involved child (2).

Breeding Dependence

Such deprivation of physical and social contingencies can lead to secondary developmental problems, including limiting motivation to explore the environment. This motivation effect is termed learned helplessness, a condition in which the child gives up trying to control his or her own world because of motor disability and diminished expectations of caregivers (3).

Butler (1998) also found that children whose mobility is limited during early childhood develop a pattern of apathetic behaviors—specifically a lack of curiosity and initiative. In essence, being deprived of the experience of self-initiated mobility may keep these children dependent.

Fostering Independence

Sound empirical evidence demonstrates that children with disabilities using mobility devices became less dependent on controlling their environment using verbal commands, more interested in the environment and peer interaction (4). By providing a means for self-initiated mobility we are fostering a sense of independence and curiosity. The longer a child is without self-initiated mobility the more profoundly cognitive, social, language and motor skills will be delayed.

In other words, if we provide mobility to a young child we may prevent the range of deficits that come with the lack of mobility experience noted above. But if we are considering a 2-year-old that has not had self-initiated mobility we will see a greater array of challenges and difficulties since their lack of control and independence may have led to apathy. Based on this alone, we understand that a trial of the device should start as early as 12 months of age.

Prerequisites

Since the evidence supports that children are less dependent when provided with self-initiated mobility, what are the pre-requisite skills for a young child to trial the Explorer Mini? We know that this device was designed for children who have limited, or no mobility and the device has incorporated the postural support required not only for safety, but to promote freedom of movement, trunk and head control and hands coming to midline.

Since the Explorer Mini is the only device of its kind, we don’t have the data to provide specific pre-requisites for use. But we do know what happens with extended periods of immobility for these children. Allowing infants as young as 12 months to trial the Explorer Mini may prevent the learned helplessness and loss of curiosity that can occur with children who have been immobile. Be proactive in providing every opportunity for an infant to achieve self-initiated mobility and contact us here for a trial.  


1. Butler, P.B. (1998) A preliminary report on the effectiveness of trunk targeting in achieving independent sitting balance in children with cerebral palsy. Clinical Rehabilitation, 12, 281-293.

2. Butler, P. (1988). High tech tots: Technology for mobility, manipulation, communication, and learning in early childhood. Technology, Infants Young Children, 1, 66-73

3. Weisz JR (1979) Perceived control and learned helplessness among mentally retarded and nonretarded children: a developmental analysis. Developmental Psychology 15(3): 311–9470

4. Paulsson K Christofferson M – 1986 – Psychosocial aspects of technical aids How does independent mobility affect the psychosocial and intellectual development of children with physical disabilities.pdf.

 

Dr Teresa Plummer, PhD, OTR/L, ATP, CEAS, CAPS

Associate Professor in the School of Occupational Therapy at Belmont University

Dr Teresa Plummer, PhD, OTR/L, ATP, CEAS, CAPS is an Associate Professor in the School of Occupational Therapy at Belmont University in Nashville, TN. She has over 40 yrs of OT experience and 20 in the area of Assistive Technology.

She is a member of the International Society of Wheelchair Providers, and the Clinicians Task Force. She is a reviewer for American Journal of OT and guest reviewer for many other journals. She has authored journal articles and textbook chapters in the area of OT and pediatric mobility and access.

Early Milestones: Developing Proximal Stability

 


Welcome to Part 4 in our series about developmental milestones in early childhood focusing on mobility. See Part 1, Part 2, and Part 3 below in case you missed them earlier!


A young infant begins by weight bearing through hands, knees and toes. This proximal stability is what allows him to hold his head against gravity. This is a critical part of development. At two months of age this action is what facilitates head control and is linked to oculomotor control which is the foundation of visual skills.

At this point the infant begins to develop visual fixations and is able to bring both eyes (controlled by six oculomotor muscles) together to stabilise his gaze. Infants who have not developed this trunk control lack the ability to gain full head and eye control. Without proximal control of the trunk and the development of eye gaze, a child’s development will be greatly altered.  

The seat surface and opportunity for weight bearing in the Explorer Mini aims to mimic this posture to augment the non-mobile infant.

So while a young child may not yet have full head control, the use of the Explorer Mini provides a supportive seat and weight bearing surface to encourage further development of the trunk, visual and vestibular system while providing proprioceptive input which stimulates co-contraction at the weight bearing joints, to help promote improved head control. 

How sitting typically develops:

3-5 Months: Pre-sitting period, single postural muscles are activated. For an infant at this age they need postural support and opportunities for supportive sitting.

5-6 Months: A young child can sit with arm support.

7-10 Months: The leg, trunk and neck muscles are activated and cooperate in sitting and reaching activities.

9 Months to 3 Years: The young child has good modulation of pelvic muscles for a stable base of support.

3 Years and Beyond: The child needs less co-contraction and the use of neck muscles for postural control (6). 

 

How does the Explorer Mini provide postures to mimic the stages a young child goes through for sitting?

For the non-ambulatory child, a stable base of support is realised in the Explorer Mini by many contact points and a wide base of support, as is provided in a variety of positions by the adjustable seat and tray surfaces. In contrast to a device that positions the child in a non-active sitting position, a child will typically assume a slumped posture with weight bearing behind the ischial tuberosities and no mechanoreceptors are activated. 

The saddle seat surface of the Explorer Mini places the weight bearing in front of the ITs to facilitate weight bearing through the upper extremities, while the pelvis is positioned in a forward/anterior tilt, with the hip position signaling the erector spinal muscles (or back muscles) to activate.

This device not only allows a young child to independently move, but it also promotes postures that may help them reach developmental milestones over time. Rather than limiting non-mobile young children to lay in a stroller or bed, we can use the Explorer Mini to help trigger muscle activation in postures that are safe and stable. 


1.Hagert, E., Persson, J., Werner, M., & Ljung, B-O. (2009). Evidence of wrist proprioceptive reflexes elicited after stimulation of the scapholunate interosseous ligament. American Society for Surgery of the Hand, 34A. 642-651.

2.Henderson, A., & Pehoski, C., (2006). Hand Functions in the Child: Foundations for Remediation, 2nd edition. Mosby, Elsevier. St. Louis, Missouri.

3.Michelson, JD, & Hutchins, C., (1995), Mechanoreceptors in human ankle ligaments. The Journal of Bone and Joint Surgery. British vol. 77-B

4.Rosenblum, S., & Josman, N. (2003). The relationship between postural control and fine manual dexterity. Physical and Occupational Therapy in Pediatrics, 23,(4). 47-60.

5.Stavness, C., (2006). The effect of positioning for children with Cerebral Palsy on upper-extremity function: A review of the evidence. PT and OT in Pediatrics, 26,39-52

6.Westcott, S., & Burtner, P. (2004). Postural control in children: Implications for pediatric practice. PT and OT in Pediatrics, 24, 5-55.

7.Scheiman, M. (2011). Understanding and managing vision deficits: A guide for occupational therapists. Thorofare, NJ: SLACK Incorporated.

 

 Dr Teresa Plummer, PhD, OTR/L, ATP, CEAS, CAPS

Associate Professor in the School of Occupational Therapy at Belmont University

Dr Teresa Plummer, PhD, OTR/L, ATP, CEAS, CAPS is an Associate Professor in the School of Occupational Therapy at Belmont University in Nashville, TN. She has over 40 yrs of OT experience and 20 in the area of Assistive Technology.

She is a member of the International Society of Wheelchair Providers, and the Clinicians Task Force. She is a reviewer for American Journal of OT and guest reviewer for many other journals. She has authored journal articles and textbook chapters in the area of OT and pediatric mobility and access.