Blog posts of '2021' 'October'


October is Spina Bifida Awareness Month, and like all awareness months it is a good opportunity to learn something new.  For me, it has been some time since I explored the research for Spina Bifida, so it was a good prompt to pause and take a look on PubMed to see what research I could find.    

The incidence of babies born with Spina Bifida has decreased since the link to maternal folate intake was observed, however small number of babies continue to be born each year with Spina Bifida.  For many of us, older children and adults with Spina Bifida form part of our caseload, where we regularly see the diversity of presentations and abilities within this group.   

For those who are less familiar with Spina Bifida, Spina Bifida is a type of neural tube defect that occurs when a baby’s neural tube fails to develop or close properly – the literal meaning for Spina Bifida is split spine’. Typically occurring within the first 28 days of pregnancy (while the neural tube is forming), Spina Bifida often occurs before a woman knows she is pregnant.  The cause of this neural tube defect is unknown; however it is believed to be a complex mix of both genetic and environmental factors acting together.  

There are three types of Spina Bifida 

  • Spina Bifida Occulta  this form usually does not cause any impairment and does not have any visible signs as the spinal cord and nerves are unaffected.  It is typically discovered as an incidental finding on an X-Ray that is done for other reasons.  

  • Meningocele – this causes part of the spinal cord to come through the spine like a sac that is pushed out. Nerve fluid is in the sac, and there is usually no nerve damage. Individuals with this condition may have minor disabilities. 

  • Myelomeningocele (also called Spina Bifida Cystica) - this is the most severe form of Spina Bifida. This happens when parts of the spinal cord and nerves come through the open part of the spine. It causes nerve damage and other disabilities.  


The Spina Bifida Association of America offers an impressive number of resources for families, clinicians and educators, and they appear to be linked to the publication of a number of care guidelines for people with Spina Bifida.  One recently published guideline relates to skin integrity guidelines over childhood and into adulthood (Beierwaltes et al, 2020), while another that caught my interest was the Neuropsychological Care Guidelines (Queally et al, 2020). 

Prior to looking at the neuropsychological care guidelines, it is worth noting that Spina Bifida Myelomeningocele (SBM) is also associated with a collection of changes in the brain.  Looking at an article published by Juranek and Salman (2010), it is acknowledged that the failure in neural tube closure at the level of the spine also results in altered brain development, in both its structure and how it functions.  Studies have documented a remarkable degree of variation among individuals with SBM in terms of the size, shape, and appearance of the cerebellum, corpus callosum, and cerebral cortex. Similarly, a wide range of cognitive strengths and relative weaknesses among individuals with SBM are also documented in the published literature. 

Common structural characteristics associated with SBM include (Juranek and Salman 2010) 

  • Changes in the development of the skull 

  • Chiari II malformation – complex changes that involve the midbrain and hindbrain (i.e. pons, medulla, and the cerebellum) and cervical spinal cord, it is also associated with a significantly smaller posterior fossa with its contents crowded and distorted in appearance  

  • Hydrocephalus 

  • Corpus callosum hypoplasia and dysgenesis  

(For an overview of the anatomy of the brain, please see 

Coming back to the neuropsychological care guidelines (Quelly et al 2020), it is noted that individuals with Spina Bifida show a pattern of strengths and weakness across different areas, with a particular pattern seen with individuals who are born with a myelomeningocele, as comparted to individuals born with other types of Spina Bifida, who tend to have a more typical cognitive development.  

Individuals with Spina Bifida Myelomeningocele (SBM) tend to show strengths in learning skills that rely on rule-based processing (e.g., math fact retrieval, word reading) but have some difficulties when learning how to integrate this information (e.g., math problem-solving, reading comprehension).  In language and reading areas, vocabulary, grammar, and word recognition are strengths, however, children with SBM experience challenges in listening and reading comprehension, with the cause of these challenges being linked to changes in the corpus callosum.   In mathematics, children with SBM can learn math facts; however, complex procedures that require multiple steps and algorithms are an area of challenge. They often experience difficulties with estimating quantities and have impaired math problem-solving skills. 

Many children with SBM also meet criteria for Attention Deficit/Hyperactivity Disorder, however their presentation differs to children with developmental forms of ADHD related to self-regulation.  The attention profile of children with SBM is characterized by under-arousal and are related to disruptions in midbrain and posterior cortexwith evidence of this present from infancy.  

There remains a large amount of variability in the neuropsychological outcomes of people with SBM, these can be attributed to variability in the changes in the brain, as well as variables that impact on all individuals, such as socio-economic status and education.   Health related challenges, such as more severe hydrocephalus or repeated shunt malfunctions can also influence outcomes, and individuals with higher lesion levels have more severe neuroanatomic brain malformations and higher rates of intellectual disability. 

The neuropsychology guidelines offer evidence based or best practice recommendations for children by age group, highlighting different areas of cognitive development that needs to be considered.  The ultimate goal for these guidelines is to maximise a persons performance in education and in turn their ability to participate in both employment and independently in the wider community.  

Another article that caught my attention was the The Management of Myelomeningocele Study by Farmer et al (2018).  This article followed on from previously published research on this randomised control trial.  The Management of Myelomeningocele Study (MOMS) was a multi-centre study comparing outcomes of an antenatal repair to the traditional postnatal repair, with 183 people recruited for the study, randomised into two groups.  Eligible patients were women carrying a foetus diagnosed with Spina Bifida Myelomeningocele between 19-25 weeks gestation.   Initial outcomes of the study demonstrated that prenatal repair of the myelomeningocele reduced the need for cerebrospinal fluid shunting and improved neurologic function.  A urologic subgroup study identified that prenatal surgery did not reduce the need for clean intermittent catherization, however it did reduce the incidence of secondary complications of the bladder.  The prenatal surgery group featured less females and the level of the lesion tended to be higher, however when followed up at 30 months of age, children in this group were more likely to have a level of function better than expected according to the anatomical level of the lesion.  The prenatal group were also more likely to walk (44.8% vs 23.9%) and have better gross motor skills.    

The research team explored the prenatal surgery group further, to help identify which children are likely to benefit most from the prenatal surgery, given prenatal surgery does not come without its risks.  Looking at the 39 children who later gained independent walking, these children all demonstrated spontaneous hip movement (with 38 also demonstrating knee movement) in their antenatal ultrasound.  However only approximately half of those shown to have hip or knee movement on ultrasound could later walk.  For the nine children who did not demonstrate any hip movement on ultrasound, none of these children could walk independently at 30 months.  Other factors that correlated with the ability to walk included the level of the lesion and the absence of a sac over the lesion, however the need for a shunt was not associated with motor function.  The 30 month review also assessed for cognitive development, however no differences in cognitive development were seen between the groups.  

For those who are keen to learn more about Spina Bifida, the American Spina Bifida awareness website is well worth a visit, other resources include orthopaedic management, aging with Spina Bifida and general wellbeing, not to mention easy to read resources for parents. - American Spina Bifida Association 

Beierwaltes, P., Munoz, S. & Wilhelmy, J.  (2020) Integument: Guidelines for the care of people with spina bifida.  Journal of Pediatric Rehabilitation Medicine: An Interdisciplinary Approach. 13: 543-548 DOI 10.3233/PRM-200723 

Farmer, D.L., Thom, E.A., Brock, J.W., Burrows, P.K., Johnson, M.P., et al (2018) The Management of Myelomeningocele Study: full cohort 30-month pediatric outcomes.  Americal Journal of Obstetrics & Gynecology. 

Juranek, J. & Salman, M.S. (2010) Anomalous development of brain structure and function in spina bifida myelomeningocele.  Dev Disabil Res Rev. 16(10) 23-30. doi:10.1002/ddrr.88. 

Quelly, Q.T., Barnes, M/A., Castillo, H., Castillo, J., Fletcher, J.M. (2020) Neuropsychological care guidelines for people with spina bifida.  Journal of Pediaric Rehabilitation Medicine: An Interdisclipinary Approach.  13: 663-673 DOI 10.3233/PRM-200761


Rachel Maher
Clinical Education Specialist
Rachel Maher graduated from the University of Otago in 2003 with a Bachelor of Physiotherapy, and a Post Graduate Diploma in Physiotherapy (Neurorehabilitation) in 2010. 
Rachel gained experience in inpatient rehabilitation and community Physiotherapy, before moving into a Child Development Service.Rachel moved into a Wheelchair and Seating Outreach Advisor role at Enable New Zealand in 2014, complementing her clinical knowledge with experience in NZ Ministry of Health funding processes. 
Rachel joined Permobil in June 2020, and is passionate about education and working collaboratively to achieve the best result for our end users. 

As technology has evolved, so too has the technology, materials and electronics that go into powered mobility base designs.  Most complex rehabilitation bases are now modular in nature, meaning multiple components can be combined to provide a solution that is unique to an individual. Some of these components are essential to the build of the chair while others are required to provide the optimal functional outcome required for the end user.

Often we only become aware of what components are required to build a chair when we receive the quote – where quotes can differ from country to country, state to state and with different suppliers. It  can be quite overwhelming when the components are itemised within a quote, especially when we are not intimately familiar with power wheelchair bases and we need to be able to complete a report to the funder to justify the cost of the solution.

How do we know what information in the quote needs to be justified in our funding report?  The foundation to any good funding report is sound and well-articulated clinical reasoning. Our clinical reasoning process should help us identify what features will be required or needed to meet the user’s identified goals. But how do we consistently achieve this? By following a process and articulating that process clearly we can demonstrate sound clinical justification.

For the purposes of this blog we will look at the dictionary definition of feature and specification and how we can use these terms to assist with our report writing.

When we look to dictionary meanings, we see a feature described as a distinctive part of something, whereas the definition of a specification is more about the recipe or the plan to build. If we consider these definitions, we can also consider features within powerbases as the additional functions it has above and beyond a standard driving base unit. The specifications then relate to how this feature is designed or operated.


Let’s take the example of a powered seat height function. The AT feature would be that you can adjust the seat-to-floor height of the base. This feature is available on a range of chairs from multiple manufacturers; however, seat elevators are designed and operate in different ways. This includes the mechanical differences; there are differences between a scissor lift, a Colum lift and Permobil’s AP unit, height ranges and travel. Once you have identified the functional requirement of a feature then you can consider the specifications and how this may impact on the functional outcome for a specific end user.

Let’s consider a client we have assessed for a powered mobility base. What are the clinical decisions that need to be made?

  1. What configuration will best meet this user’s goals? What environments and terrain do they normally traverse? What is the access like? What kind of turning spaces are required to access all areas of the home?  What experience has the user had with mobility bases? What are the barriers currently impacting on mobility? These are some of the considerations when determining the drive base. Different drive configurations will manoeuvre and drive differently in different environments. We could see the type of drive configuration as a feature of the AT, where the wheel is placed exactly, and how it attaches to the chassis would be more of a specification specific to the brand manufacturer. These specifications may come into consideration when you are comparing how a base with similar features differs.Will the user require or need power seat functions to assist them in meeting mobility and/or functional goals? Power seat functions provide increased function outcomes and indeed could be seen as beneficial to all users. However when we are seeking funding for these features we need to consider them in terms of functional outcomes. We need to identify what activities and tasks are impacted by the impairment. Will being able to complete these tasks have a functional outcome? – could the task be completed without the additional seat function? As well as forming part of the clinical reasoning process, you are identifying potential justification for requesting the feature as a funded feature. I tend to think about power seat functions as features of the AT solution. How they operate, use of actuators etc are the specifications again specific to the manufacturer.

Let’s break it down:

Assessment: identify mobility and functional issues. Identify how functional Impairment impacts on task.

As part of the clinical reasoning process – initially identify features such as PSF.

Once you identify the features required you can consider the potential solutions and specifications to compare.

When completing your report it is worth noting which components are essential to the build of the chair, and which components are additional and are required for the person to achieve their identified goals. For example:

While talking to some therapists recently, I have noticed an increase in the justification for functional outcomes for things that could be seen as more of a specification, for example a standard joystick. 
Looking at the big picture, the feature we are looking at here is the drive control method, or how the person will drive the chair. When considering drive control options, there are multiple options that are associated with different costs, with a joystick being the ‘standard’ and lowest cost option. Hence it does not typically require any justification, unlike alternative drive controls which are higher cost hence require additional justification in your report.

Something that is integral to the base such as the joystick for example. Whilst clearly the joystick is an AT feature of a powered wheelchair it is also integral to have a standard joystick as a minimum to operate a powered wheelchair – as such whilst it is important to have considered the input method and can be valuable to comment on, its more important to discuss any alternative controls as these are additional features that are a requirement for that specific users ability to operate their chair. Another example, the control box for seat functions – do we need to explain this or do we need to make a clear case between need and the actual seat functions recommended.

To ensure these functions are essential requirements we need to clearly articulate how these features improve functional outcomes. These examples sometimes come about because of the description or wording on the quote or how the quote has been itemised and at other times because we are not sure what a specific item is. The AT features or additional or non standard features that the clinical justification needs to focus on is the clinical outcomes and necessity for the user. If you’re not sure of a specific item on a quote reach out to your local dealer or Permobil Rep or us here at the Clinical team.

Although it can appear overwhelming, you local product specialists are there to talk you through and assist you to compare the various powered mobility bases available. They understand the specifications and how they relate to the differences in bases. We also have a range of clinical educational opportunities to assist therapists in building their knowledge and clinical prescription skills. You can reach out to us at any time for any support or to chat through a scenario. For those therapists with more experience prescribing bases make sure you keep up to date with the latest technologies and advancements by staying in touch with your local supplier and seeking experiences to try out and compare how AT features differ based on specifications.

Its important to remember we are all at different levels of experience and have different levels of clinical reasoning. If your feeling a little uncertain around the process or powered mobility base prescription reach out to your local educator at


Tracee-lee Maginnity
Clinical Education Specialist

Tracee-lee Maginnity joined Permobil Australia in July 2019, as a clinical education specialist. She graduated Auckland University of Technology with a BHSc (Occupational Therapy) in 2003 and has since worked in various roles related to seating and mobility including assessing, prescribing and educating.

Tracee-lee is passionate about maximising functional outcomes with end users and the importance of education within the industry.