Distinct multi-joint control strategies in spastic diplegia associated with prematurity or Angelman syndrome

• Published in: Clinical neurophysiology Vol. 112; no. 9; pp. 1618 - 1625
• Main Authors: Dan, Bernard, Bouillot, Ethel, Bengoetxea, Ana, Boyd, Stewart G, Cheron, Guy
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 01-09-2001; Elsevier Science
• Subjects: Angelman syndrome; Angelman Syndrome - complications; Biological and medical sciences; Biomechanical Phenomena; Cerebral palsy; Cerebral Palsy - etiology; Cerebral Palsy - physiopathology; Child; Electrodiagnosis. Electric activity recording; Electromyography; Humans; Infant, Newborn; Infant, Premature; Investigative techniques, diagnostic techniques (general aspects); Joints - physiopathology; Leg - physiopathology; Leukomalacia, Periventricular - complications; Medical sciences; Movement; Nervous system; Posture; Reference Values; Spastic diplegia; Cerebral palsy; Angelman syndrome; Movement; Posture; Spastic diplegia; Premature; Nervous system diseases; Motor system disorder; Diplegia; Spasticity; Corticospinal bundle; Striated muscle; Motor control; Cerebral disorder; Electrodiagnosis; Cerebellar disease; Periventricular leukomalacia; Central nervous system disease; Kinematics; Body movement; Electromyography; Neurological disorder
• ISSN: 1388-2457; 1872-8952
• DOI: 10.1016/S1388-2457(01)00618-6

Spastic diplegia is commonly due to periventricular leucomalacia associated with premature birth. It is also a feature of Angelman syndrome (AS), a neurogenetic disorder with developmental delay, absent speech and mirthful behaviour. We studied the kinematics and kinetics of the squatting movement and associated electromyographic (EMG) activities in 20 children with spastic diplegia associated with periventricular leucomalacia (SDPL) or AS and 18 unimpaired children. While movement of normal subjects consisted of vertical translation of most body segments, the movement of SDPL children was operated around the fixed knee with backward shift of the hip, and AS children performed a forward flexion of the trunk over the thigh. Trunk stability was correlated with movement velocity in both pathological groups. In normal subjects, anticipatory EMG pattern consisted of silencing of hamstring muscle tonic activity prior to movement onset. This deactivation was not present in spastic diplegia. In SDPL, anticipatory overactivation of ankle joint actuators was recorded and tonic co-contraction persisted throughout the movement. In AS, rhythmic EMG bursting was seen during the movement. Shoulder, hip and knee trajectories in the sagittal plane showed marked within-group stereotypies in orientation, shape and length. The patterns in both pathological groups were therefore distinctive. We speculate that they reflect corticospinal impairment in SDPL and combined corticospinal and cerebellar dysfunction in AS.