ABSTRACT
OBJECTIVE: Children with a neuromuscular disease are prone to early muscular fatigue. The objective of the present study was to evaluate the effects of fatigue induced by a walking exercise on the strength, postural control, and gait of children with a neuromuscular disease. DESIGN: Maximal isometric knee strength (extension and flexion), quiet standing postural control, and gait were evaluated in 12 children (8.8 [1.4] yrs) with a neuromuscular disease before and after a walking exercise. The participants were asked to stop walking when they considered themselves "very fatigued." RESULTS: After the exercise-induced fatigue, a significant increase in range of motion in pelvis obliquity, hip abduction and adduction, and ankle flexion and extension during gait was reported along with an increase in stride length variability. Fatigue also reduced the knee flexor strength and had a detrimental effect on postural control. CONCLUSIONS: Fatigue affects the strength, postural control, and gait of children with a neuromuscular disease and could notably increase the risks of falling and the occurrence of serious injuries.
Subject(s)
Exercise/physiology , Muscle Fatigue/physiology , Muscle Strength , Neuromuscular Diseases/rehabilitation , Ankle Joint/physiopathology , Child , Female , Gait , Hip Joint/physiopathology , Humans , Knee/physiopathology , Knee Joint/physiopathology , Male , Neuromuscular Diseases/physiopathology , Postural Balance , Range of Motion, ArticularABSTRACT
Data reported here were collected over an 8-year period for 79 Duchenne muscular dystrophy patients, 37 of whom were treated with deflazacort. Mean length of treatment was 66 months. Treated boys stopped walking at 11.5 +/- 1.9 years, compared with 9.6 +/- 1.4 years for untreated boys. Cardiac function was better preserved with the use of deflazacort, as shown by a normal shortening fraction in treated (30.8 +/- 4.5%) vs untreated boys (26.6 +/- 5.7%, P < 0.05), a higher ejection fraction (52.9 +/- 6.3% treated vs 46 +/- 10% untreated), and lower frequency of dilated cardiomyopathy (32% treated vs 58% untreated). Scoliosis was much less severe in treated (14 +/- 2.5 degrees ) than in untreated boys (46 +/- 24 degrees ). No spinal surgery was necessary in treated boys. Limb fractures were similarly frequent in treated (24%) and untreated (26%) boys, but vertebral fractures occurred only in the treated group (7/37) (compared with zero for the untreated group). In both groups, body weight excess tripled between the ages of 8 and 12 years. All untreated patients grew normally (>4 cm/year), as opposed to only 15% of treated boys. Deflazacort improves cardiac function, prolongs walking, and seems to eliminate the need for spinal surgery, although vertebral fractures and stunted growth occur. The overall impact on quality of life appears positive.
