Upper Limb Evaluation and One-Year Follow Up of Non-Ambulant Patients with Spinal Muscular Atrophy: An Observational Multicenter Trial

Abstract

Assessment of the upper limb strength in non-ambulant neuromuscular patients remains challenging. Although potential outcome measures have been reported, longitudinal data demonstrating sensitivity to clinical evolution in spinal muscular atrophy patients are critically lacking. Our study recruited 23 non-ambulant patients, 16 patients (males/females = 6/10; median age 15.4 years with a range from 10.7 to 31.1 years) with spinal muscular atrophy type II and 7 patients (males/females = 2/5; median age 19.9 years with a range from 8.3 to 29.9 years) with type III. The Brooke functional score was on median 3 with a range from 2 to 6. The average total vital capacity was 46%, and seven patients required non-invasive ventilation at night. Patients were assessed at baseline, 6 months, and 1 year using the Motor Function Measure and innovative devices MyoGrip, MyoPinch, and MoviPlate, which assess handgrip strength, key pinch strength, and hand/finger extension-flexion function, respectively. The study demonstrated the feasibility and reliability of these measures for all patients, and sensitivity to negative changes after the age of 14 years. The younger patients showed an increase of the distal force in the follow-up period. The distal force measurements and function were correlated to different functional scales. These data represent an important step in the process of validating these devices as potential outcome measures for future clinical trials.Trial RegistrationClinicalTrials.gov NCT00993161

Longitudinal functional and NMR assessment of upper limbs in Duchenne muscular dystrophy

“…Exclusion criteria were the following: inability to sit upright in a wheelchair for at least 1 hour, severe intellectual impairment preventing full understanding of tests, recent upper limb surgery or trauma, or known immunodeficiency. All patients underwent clinical and functional assessments every 6 months using the Motor Function Measure (MFM; http://www.motor-functionmeasure.org) and the MyoSet devices specifically developed and validated for weak patients 4,5,23 (MyoGrip and MyoPinch for hand grip and key pinch strength and MoviPlate for function). Patients were assessed by NMRS and NMRI annually.…”

Treatment Advances in Spinal Muscular Atrophy

“…The 6-minute walk test (6MWT) is an additional functional score that is applicable for patients who are independently ambulant. This test can measure exercise capacity and is sensitive to fatigue related changes in SMA [8–10]. Functional tests for infants with SMA include the Hammersmith Infant Neurological Exam part 2 (HINE-2) and the Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND) [8].…”

213th ENMC International Workshop: Outcome measures and clinical trial readiness in idiopathic inflammatory myopathies, Heemskerk, The Netherlands, 18–20 September 2015

“…These methods can be subdivided in 5 categories: MMT, hand-held dynamometry (HHD), fixed dynamometry (generally referred to as quantitative muscle testing or “QMT”), isokinetic dynamometry (such as with a Biodex) and specific dynamometry (à la carte designed devices). He illustrated the correlations obtained between MMT, QMT and Biodex measurements in healthy subjects, Duchenne dystrophy or spinal muscular atrophy patients [41,42]. He illustrated the relationship between strength and motor abilities (evaluated by functional tests such as the 6 minute walking distance (6MWD)), leading to ceiling effects (increasing strength on QMT with a constant distance traveled on the 6MWD) or floor effects (undetectable observed effect such as for patients incapable of walking who achieve a 6MWD of 0, despite a measurable generated force on QMT).…”