P.166 Clinical outcome study of dysferlinopathy: The impact of lower limb orthoses on gait- a longitudinal single case study

Abstract

Patients with limb girdle muscular dystrophy, LGMDR2/2B, caused by mutations in the <i>DYSF</i> gene, have a distinct gait pattern and may be prescribed Ankle Foot Orthosis (AFOs) to assist walking. However, there are few studies investigating the efficacy of orthoses in LGMD. In the Jain Foundation clinical outcome study for dysferlinopathy II (COSII, http://www.jain-foundation.org/dysferlinoutcomestudy), we are investigating the utility of instrumented gait analysis as a novel clinical biomarker. The aim of this study was to examine the temporospatial gait parameters of a 30-year-old male with LGMDR2, when walking shod, with and without a pair of silicon AFOs. The patient completed gait analysis at baseline and six-month visits using an instrumented walkway, the GAITRite, 240Hz. Temporospatial characteristics including gait velocity, step length, step width, stance and swing duration were extracted. The differences between walking with and without the AFO were examined at each time point and longitudinally. At baseline, when wearing the AFOs, there was negligible impact on walking speed, step length, stance time compared to shod walking without AFOs (<3% difference between walking conditions). Step width increased by 25% when wearing the AFOs. At six months, his shod walking speed and step length demonstrated little change (<5%), but step width increased by 12% and double limb support increased by 5%. When wearing the AFOs at six months, and compared to shod walking, walking speed and step length increased by <5%, double limb support reduced by 6% and step width increased by 11%. The patient reported at both time points that he wouldn't walk outside the home without wearing the AFO. This study has demonstrated that AFOs influenced gait outcomes relating to dynamic balance control and stability. Although only minimal changes were observed when wearing the AFO at baseline, substantial improvements in walking were observed when wearing the AFO at six months. Further work in a larger number of patients will help to understand indications for AFO prescription in LGMDR2 and other LGMDs.