Shorts: Multiple Sclerosis- overview and orthotic management
Multiple Sclerosis (MS) is an acquired condition, which results in chronic inflammation of the central nervous system. Plaques form on demyelinated neurons in regions of white matter in the brain and spinal cord, and this “scarring” or “sclerosis” is where the name comes from. This demyelination of both motor and sensory neurons interferes with impulses that travel in (afferent) and out (efferent) of the spinal cord and can result in neurological impairment.
Because MS can affect both upper and lower motor neurons, an individual may experience spasticity and/or weakness. Plaques can also form on sensory neurons which result in disrupted sensation and proprioception.
MS affects roughly 1 in 100,000 people, is the most common cause of serious physical disability in adults of working age. Typical onset of symptoms occurs in late 20s.
There are currently four identified distinct types of MS.
Clinically Isolated Syndrome (CIS) is a first episode of symptoms of MS which does not meet the criteria for a full diagnosis of the disease. Relapsing-remitting MS (RRMS) is the most common form of the disease (approximately 85% of cases are initially diagnosed as RRMS) and is characterised by episodes (relapses) where symptoms worsen before periods of partial or full recovery (remissions). Symptoms which develop during relapses may become permanent, lessen in severity or completely disappear following a relapse.
In Primary Progressive MS (PPMS) there is a general trend of worsening neurological function, and increase in measures of disability from the onset of symptoms. There may be some patterns of relapse later in the course. Secondary Progressive (SPMS) is a course which begins as RRMS and then develops into a progressive worsening of symptoms. Because of the progressive nature of these courses, the needs of individuals with MS will likely change over time as the level of neurological disfunction increases. More proximal muscle groups may become affected, the level of hyper/hypotonicity may increase or completely new muscle groups may become affected as the disease progresses.
Clinical presentation
Symptoms including:
- Loss or reduction of vision in one eye with painful movements, double vision
- Ascending sensory disturbance and/or muscle weakness
- Problems with balance and fine motor skills
- Spasticity
- Fatigue
- Lhermitte’s sign (sensation down back like an electric shock when the neck is bent forward)
Orthotic intervention
The primary goals of orthotic intervention for patients with MS are typically:
- to support weakened musculature and assist with lost/impaired function, which can also help to reduce fatigue and reduce risk of falls,
- to address instability and difficulties with balance, because of weakness or reduced proprioception,
- to help individuals manage the effects of spasticity.
Distal weakness can result in a flaccid foot drop, which may lead to increased risk of falls due to reduced ground clearance or higher energy expenditure due to compensatory movement patterns (for example steppage gait, where the hip and knee flex more during swing phase to help achieve clearance).
A Posterior Leaf Spring (PLS) style Ankle Foot Orthosis (AFO) can be effective if the weakness is only affecting the ankle dorsiflexors and the individual does not require support in the transverse (M-L) plane, and if there is no spasticity present. In cases where there is Oxford Muscle Power of 4, a minimal style off the shelf device such as a Boxia ankle splint or Foot Up may provide the required level of plantarflexion resistance. Functional Electrical Stimulation (FES) may also be beneficial for patients with focal weakness of the dorsiflexors, in the absence of spasticity.
For individuals requiring greater resistance to plantar flexion or where there is a need for triplanar control at the ankle because there is weakness affecting inversion and eversion at the subtalar joint, a rigid AFO can be beneficial. The AFO should be tuned in appropriate footwear to facilitate progression through gait (SVA between 10° and 12°). If there is any contracture or functional limitation found during clinical assessment, then both the saggittal angle the AFO holds the ankle in and the SVA need to be altered accordingly.
For individuals where there is weakness in more proximal muscle groups, orthoses acting across multiple joints such as KAFOs, HKAFOs could be appropriate.
Spasticity secondary to MS may require input from an orthotist. Individuals may benefit from progressive stretching using resting splints, especially when used in conjunction with Botox injections and physio input. Common medications taken to reduce spasticity are gabapentin and baclofen. Spasticity has been reported to affect between 45% and 70% individuals with MS at some point. Spasticity is commonly quantified using the Modified Ashworth Scale or the Tardieu Scale.
Individuals with abnormal tone (increased or decreased) may benefit from dynamic movement orthoses (DMOs), garments fabricated from materials such as lycra. The garments help manage tone by increasing sensory and proprioceptive feedback and can improve motor function. Pain can be reduced as the garments influence postural control and can provide support across joints to help with positioning. Because of the focal nature of hypo- and hyper-tonia secondary to MS, it is likely that individual garments such as gloves will be more appropriate than a full suit which may be more beneficial in the management of the more wide-spread effects of dystonic cerebral palsy, for example.
Some medications that are taken to try and slow progression of MS and/or prevent flare ups work by lowering white blood count. This means that some individuals will have a lowered immune response, which makes things like following effective infection control measures in clinic essential.
Input from other professionals
Spasticity management- focal Botox injections by a consultant or specialist.
Physical therapy including stretching and exercise can also help with symptoms including fatigue, depression and weakness as well as spasticity. Gait training with a physiotherapist (with or without orthotic intervention) can be beneficial, especially when using unfamiliar equipment. Robotic assisted gait training is a less common option due to the limited availability and cost of equipment, but has shown some promising potential for individuals that are severely affected by the condition. Input from speech and language therapists and occupational therapists can support individuals to continue to be independent if their symptoms worsen.
References and further reading:
NICE (2019). Multiple sclerosis in adults: management: Clinical guideline [CG186]
Bulley, C., Mercer, T. H., Hooper, J. E., Cowan, P., Scott, S., & van der Linden, M. L. (2015). Experiences of functional electrical stimulation (FES) and ankle foot orthoses (AFOs) for foot-drop in people with multiple sclerosis. Disability and rehabilitation. Assistive technology, 10(6), 458–467. https://doi.org/10.3109/17483107.2014.913713
Bregman DJJ, De Groot V, Van Diggele P, Meulman H, Houdijk H, Harlaar J (2010) Polypropylene ankle foot orthoses to overcome drop-foot gait in central neurological patients: a mechanical and functional evaluation. Prosthetics and Orthotics International 34(3): 293–304
Owen E. The Importance of Being Earnest about Shank and Thigh Kinematics Especially When Using Ankle-Foot Orthoses. Prosthetics and Orthotics International. 2010;34(3):254–269. doi:10.3109/03093646.2010.485597
Barnes MP, Kent RM, Semlyen JK, McMullen KM. Spasticity in
multiple sclerosis. Neurorehabil Neural Repair 2003;17:66–70.
Vender JR, Hughes M, Hughes BD, Hester S, Holsenback S, Rosson B. Intrathecal baclofen therapy and multiple sclerosis: outcomes and patient satisfaction. Neurosurg Focus. 2006 Aug 15;21(2):e6. doi: 10.3171/foc.2006.21.2.7. PMID: 16918227.
Dynamic movement lycra orthosis in multiple sclerosis, Liz Betts, British Journal of Neuroscience Nursing 2015 11:2, 60–64
Gracies J-M, Marosszeky JE, Renton R, Sandanam J, Gandevia SC, Burke D. Short-term effects of dynamic Lycra splints on upper limb in hemiplegic patients. Arch Phys Med Rehabil 2000;81:1547–55
Anne Shumway-Cook, Marjorie H Woollacott Motor Control: Linking research to clinical practice
Vaney C, Gattlen B, Lugon-Moulin V, et al. Robotic-Assisted Step Training (Lokomat) Not Superior to Equal Intensity of Over-Ground Rehabilitation in Patients With Multiple Sclerosis. Neurorehabilitation and Neural Repair. 2012;26(3):212–221.
