F EASIBILITY C ASE S TUDY ON THE USE OF D YNAMIC E LASTOMERIC F ABRIC O RTHOSES IN CMT​ Sarah Brown ​ Paediatric Neuromuscular Physiotherapist ​ Royal Hospital for Children, Glasgow ​ 25th April 2016

Introduction Why research?​ Why this study in this patient group?​ Who is involved?​ What are we doing?​ What do we hope to find out?​

Why research? There has been a surge in neuromuscular research in recent years.​ It can be challenging to conduct research in a limited population that is classed as a rare disease (an incidence of less that 5:10,000, WHO, 2012).​ A large enough sample population is required to produce clinically valid results.​ Limitations in funding and staffing.​ There is a lack of evidence for many of the interventions for this patient group and in this evidence based climate we need to work towards finding this information to improve our knowledge and impact patient care.

Aim To investigate the difference between an ankle foot orthosis (AFO) and dynamic elastomeric fabric orthosis (DEFO) on gait and fatigue in a young person with Charcot Marie Tooth (CMT).

Why this patient group? CMT is a genetic condition affecting the motor and sensory peripheral nerves. Damage to either the axon or myelin sheath results in weaker conduction of the electrical signals between the brain and muscles and causes muscle weakness and altered sensation (MDUK, 2014). CMT commonly affects the peroneal nerve resulting in weakness of tibialis anterior, extensor digitorum and hallucis brevis and peroneus brevis and longus. Ankle dorsiflexion and eversion weakness causes "foot drop" which can result in significant gait abnormalities, increased falls risk and foot posture abnormalities.

Why this patient group? This symptom of CMT is commonly managed by rigid AFOs to help to maintain a neutral ankle position and aid toe clearance when walking. Some of our patients have reported difficulties with their rigid AFOs such as: – discomfort and pressure pain – reduced proprioceptive feedback – increased trips and falls – functional limitations such as difficulty managing stairs, rising from a chair and cycling due to the restricted dorsiflexion range of movement.

Why this patient group? In CMT, the muscles of the trunk and lower limbs are weaker so balance is already affected, but the reduced proprioceptive feedback further challenges balance. A rigid AFO may be posturally correct, but it actually inhibits the normal function of the muscles of the lower leg which compromises muscle strength. In addition, the fixed position of the foot can cause increased muscle fatigue as the other muscles of the lower leg are mechanically disadvantaged.

Why this patient group? There is an increasing use of lycra in patients with neurological conditions to help to aid posture, joint position, facilitate movement and manage tone. There is limited availability of evidence in the CMT patient group, particularly in paediatrics and more specifically with relation to foot drop. With the increasing need for evidence-based justification for the use of treatment modalities we have a duty to this patient group to use our position in this specialist service to further inform clinical practice.

Who is involved in the study? Principal Investigator: Sarah Brown, Specialist Paediatric Neuromuscular Physiotherapist, RHC, Glasgow Marina DiMarco, Principal Neuromuscular Physiotherapist, West of Scotland Dr Iain Horrocks, Consultant Paediatric Neurologist, RHC, Glasgow Matthew Banger, Research Asscociate, Department of Biomedical Engineering, Strathclyde University Patricia McCotter, Orthotist, DM Orthotics

Study Aim To investigate the difference between an AFO and DEFO on gait and fatigue in a young person with CMT.

Process IRAS form and ethics process Select a paediatric patient with CMT who is an existing AFO wearer. Gain consent Initial physio assessment including joint ROM, muscle strength and a modified North Star assessment. Baseline visit - Gait assessment on the force plate and on the treadmill in normal footwear and initial fatigue questionnaire.

Process (cont.) Review one week later for gait assessment in AFOs. DEFO fitting one week later and patient to wear for 6 weeks to get used to them. Gait assessment with DEFOs, repeat fatigue questionnaire and physio assessment. Review one week later for gait analysis in normal footwear to see if there is any carry over effects from the DEFO use.

Other possibilities… ? Addition of a fatigue diary for patient to complete throughout the study. ? Additional objective outcome measures such as the 6 minute walk test or similar

What do we hope to find? We aim to examine the potential differences, if any, in: – Fatigue levels – Gait pattern – Muscle Strength – Ankle ROM

Conclusion There is a need for research into this patient group and if we want to explore the use of new treatments and devices we need to be part of the process of finding evidence to support it. Single case studies are becoming increasingly important in informing preliminary research, particularly in conditions with small sample sizes. This is a feasibility study with a single patient, but the hope is to widen the study to increase the sample size in both the paediatric and adult populations.

Any questions?