Measurement Scales for Spinal Muscular Atrophy (SMA)

Varying challenges people with different types of SMA face on a daily basis demand thoughtful ways to measure motor function and clinical outcomes.

Motor Function Measure 32 (MFM-32):

Assesses 32 different motor functions in individuals with SMA Type 2 or 3, such as head support, hip and knee flexion, upper limb function, sitting, standing, finger and wrist movement, walking, running and hopping

Hammersmith Motor Scale-Expanded (HFSME):

Assesses different motor functions in individuals aged 2 years and older with SMA Type 2 or 3, such as lying, rolling, crawling, kneeling, standing, walking, running and jumping

Revised Upper Limb Module (RULM):

Includes 19 scorable items of upper limb function and strength in people aged 30 months and older with SMA Type 2 or 3, e.g., bringing hands from lap to table, picking up coins from a table and bringing cup to mouth

Six-Minute Walk Test (6MWT):

Measures distance walked in 6 minutes to evaluate exercise capacity in individuals of walking age with SMA Type 3, e.g., walking speed

SMA Independence Scale (SMAIS):

Assesses the ability of people with SMA Type 2 or 3 to independently perform activities of daily living, e.g., feeding, moving about the home in a wheelchair and turning a page in a book

Bayley Scales of Infant and Toddler Development Third Edition (BSID-III) Gross Motor Scale:

Developmental scale designed to measure a range of motor functions in infants and toddlers aged 1-42 months with SMA Type 1 or 2, including rolling, sitting upright, crawling, stepping motions, standing, walking, climbing stairs, running, maintaining balance and other activities requiring full body control or coordination

Hammersmith Infant Neurological Examination (HINE) Section 2:

Evaluates a variety of motor skills of infants aged 2-24 months with SMA Type 1, including voluntary grasp, ability to kick, head control, rolling, sitting, crawling, standing and walking

Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND):

Measures 16 items of both observational and elicited motor activity in infants and older children with SMA Type 1, e.g., spontaneous arm and leg movement, hand grip, head control in supine and sitting and elbow extension in supported sitting