Ulla Werlauff Methods to assess physical functioning - Danske ...

SUMMARY ENGLISH
Neuromuscular disorders encompass a variety of sub groups in which impaired muscle strength is
the principal symptom, that in most cases are caused by mutations in genes that affect the
neuromuscular unit. Despite very different phenotypes, a common feature to all neuromuscular
disorders is the impact on muscle strength, which influences all domains of function as defined in
the International Classification of Function, disability and health. When the consequences of a
neuromuscular disorder is evaluated, it is thus necessary to describe both capacity – defined as the
impact on body functions - and capability – the impact on activity and participation. This puts
demands on the assessment methods used for evaluation, which alone or in combination should be
able to provide a holistic picture of the patient.
The two disorders of interest in this thesis are spinal muscular atrophy (SMA) and congenital
myopathy (CM). SMA represents a group of very weak patients in whom the natural course of
disease hasn’t been well described due to lack of responsiveness in the methods used for evaluation
of impairment and activity. Congenital myopathy is an umbrella term that covers a range of
subtypes with similarities and differences but with experienced fatigue as a general clinical
symptom, which seems to impact activity and participation, although this has never been
investigated systematically.
The four studies encompassed by this thesis investigated how the characteristic features in the two
disorders can be evaluated. The results from studies I-III contribute to the knowledge on the natural
history of SMA, and to the knowledge about which clinical assessment methods are the most
applicable to evaluate impairment and activity in these weak patients. The results suggest that upper
limbs - where muscle strength and functions are best preserved in SMA - should be the area of
focus if changes over time or results of interventions should be evaluated. Study IV concerns the
impact of fatigue as perceived by patients with SMA and CM. The hypothesis of fatigue being a
problem in patients with CM was confirmed, and the applicability of an existing instrument to
evaluate fatigue in the two disorders was illustrated. Experienced fatigue is easy to assess and
provide important information on impact of function from the patients’ perspective.
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