Proposed Topic (Most preferred): :
Clinical Safety and Quality Service I (Projects aiming to improve efficiency and effectiveness of care delivery to meet international standards)
Proposed Topic (Second preferred): :
Clinical Safety and Quality Service III (Projects aiming at quality service to patients and their carers)
Authors (including presenting author) :
Chan NC Nerita (1), Lao LM Miko (2), Chan KF Helen (2), Lai HY Joyce (1), Chan WW Stephen (1), Chan SH Sophelia (3)
Affiliation :
1. Allied Health Department (Physiotherapy), Hong Kong Children’s Hospital
2. Physiotherapy Department, Tuen Mun Hospital
3. Dept of Paediatrics and Adolescent Medicine, The University of Hong Kong
Introduction :
Patients with Spinal Muscular Atrophy (SMA) encounter different degrees of progressive muscle weakness which affects motor functions including movement and walking. Recent studies show that the use of medications (nusinersen) can preserve or even improve the function of patients with SMA. However, for those with SMA type III, the usual functional assessment scale sometimes may not be sensitive enough to detect the changes.
Objectives :
The aim of the present study is to find the change of gait parameters for patients with type III SMA after nusinersen treatment.
Methodology :
One patient with SMA type III was recruited in the gait analysis study. In addition to the usual clinical assessment using the Six-minutes-walk test (6MWT) and Hammersmith Functional Motor Scale Expanded (HFMSE), 3D gait analysis using the Vicon system and AMTI® force plates was done. The tests are to detect the kinematics and kinetics changes of the gait pattern for SMA type III patients after each dose of nusinersen treatment at 4-month interval.
The kinematics and kinetics data were analyzed. The Total Support Moment (TSM) during stance phase was assessed to compare the changes over time after each treatment. TSM is the sum of the total moment over hip, knee and ankle, indicating the total extension support of lower limbs during walking. The sum of hip, knee and ankle moments in the sagittal plane were calculated individually in each trial to provide a more comprehensive view on their contributions towards the body support.
Result & Outcome :
A total of 6 gait analyses from July 2020 to May 2022 were done for a patient with SMA type III (10 years old boy) who received the nusinersen treatment every 4 months. The trends of TSM were increased bilaterally over time, from 11.4 ± 2.3Nm/kg to 20.2 ± 4.8 Nm/kg over the left side; from 22 ± 2.5 Nm/kg to 40.2 ± 2.1 Nm/kg over the right side. While the 6MWT and HFMSE were changed from 456m to 500m and 63 to 64 out of 66 respectively. The increasing trends of TSM were perhaps a result of substantially growing contribution of ankle plantarflexion moment(24.7 ± 1.23 Nm/kg to 32.1 ± 3 Nm/kg over the left side and 31.6 ± 4.3 NM/kg to 43.5 ± 1.6Nm/kg over the right side), coupled with an increasing tendency of hip extension moment in the sagittal plane over the 6 visits (-8.2 ± 1.8 Nm/kg to -5.9 ± 2.8 Nm/kg over the left side and -3.7± 3.8 Nm/kg to -4.0 ± 2.3 Nm/kg over the right side). A slight downward trend of knee extension moment contribution were observed (-5.1 ±2.6 Nm/kg to -6.0 ± 2.0 Nm/kg for left side and -5.9 ± 2.2 Nm/kg to 0.7 ±1.6 Nm/kg for right side).
Conclusion
The results indicated the improvement in TSM in the sagittal plane which help the child to walk with a more upright or extended pattern. Particularly, the hip and ankle contribute more or compensate with the decreased knee extension moment which is comparable with our clinical observation. The gait analysis can act as an adjunct assessment in addition to the usual clinical assessment for high-functioning patients with SMA.
