Multiple sclerosis (MS) is an autoimmune disease characterized by chronic inflammation and demyelination of the central nervous system (CNS). It can affect any of the nerves within the CNS which means that symptoms and rate of progression can vary greatly between individuals.
The clinical course of the disease is quite variable ranging from stable chronic disease to a rapidly evolving and debilitating illness. The most common form of the disease is relapsing-remitting multiple sclerosis however, several other forms exist such as primary progressive and secondary progressive.
MS can cause sensory, pyramidal, cerebellar and visual symptoms which all can affect walking ability to varying degrees. Gait disturbance is arguably one of the most challenging symptoms and it is estimated that 15 years after diagnosis half of people living with MS will require help to walk and 10% need to use a wheelchair.
Gait abnormalities in people living with MS are poorly characterised despite numerous studies investigating the types of defecit found. This is surprising considering that gait retraining forms a large part of neurorehabilitation for people living with MS.
A new systematic review was published last week in the journal Diagnostics with the aim of drawing the current understanding of MS related gait abnormalities together to aid treatment and diagnostic choices particularly with classification of gait abnormalities.
Pubmed, Web of Science, PEDro and CINAHL were the databases searched and was limited to cross-sectional articles published in English, French or Spanish. There was no limit on date of publication and the base for the search strategy was as follows:
(“Visual” OR “observational” OR “pattern”) AND (“Gait” OR “ambulation” OR “walk”) AND (“Assessment” OR “evaluation” OR “Test” OR “scale” OR “measure” OR “tool” OR “analysis” OR “profiling”) AND “Multiple Sclerosis.”
To be included within the results, articles had to be cross-sectional studies which used 3-D analysis to assess gait in people over 18 years of age with confirmed MS. If observational gait assessment tools were used articles were excluded from the results so too were studies without a control group.
The quality of the studies was assessed using the Critical Review Form-Quantitative Studies scale. As well as PRISMA guidance being followed by the authors the essentials of good systematic review practice were adhered to including using a third reviewer for consensus if required.
After performing the search and reviewing results 12 articles were included within the results. This includes a total of 523 participants (342 women and 181 men). All types of MS were included within the results however some studies did not specify which type of MS some participants were living with.
Results and Clinical Implications
In all of the studies included within the review there were notable differences between control groups and those living with MS. Most noticably this includes gait speed and stride and step length. The speed defecit depends on whether the person with MS has mild (41.7cm/s slower), moderate (87.2cm/s slower) and severe (115.3cm/s) forms of MS when compared to the control group.
When comparing the technical elements of the gait cycles people living with MS have a reduced swing and stance phases likely due to areas of muscle weakness in the adductors and quads and tone changes in the hip flexors.
The muscle weakness also leads to a reduction in maximal knee flexion during the swing phase and this reduces the greater the disease severity. The same can be said for ankle dorsiflexion but this is likely caused from tone changes rather than just weakness alone.
Because of the variable location of the lesions gait abnormalities the changes seen thoughout the disease progression can and often do change. Also there will be differences between individuals when treating gait changes related to the disease. The defecits in muscle strength and increases in tone often lead to asymmtery and restoration of gait symmetry should be the aim of gait rehabilitation.