LAUSR

Background Patients with amyoplasia have severe congenital joints contractures with muscle hypoplasia or aplasia. When upper limb muscles like the biceps brachii are absent, soft tissue transplantation from different donor sites help to restore active elbow flexion and improve self-service. The current clinical study focuses on a case where successful recovery following operation and rehabilitation of the right upper limb, whilst the left was unoperated. Magnetoencephalography (MEG) was used to compare motor processes between the limbs. Material and Methods One patient (male, age 7 y.o.) post-surgery (pectoralis muscle to biceps brachii transfer) and rehabilitation, was recorded with a whole-head 306-channel Elekta MEG Neuromag at 1000 Hz, whilst lifting, reaching, and abducting the arPre/post-motion brain activity was compared between unoperated (left) and operated (right) sides in the sensor- and source spaces to pinpoint spatio-dynamics associated with muscle transplantation. Results The latency of the pre-motor responses of the unoperated limb was closer to movement onset compared to the operated limb, indicating less motor preparation. The patient showed shorter onset latency of motor-evoked activity for the operated limb compared to the unoperated limb for different movements. Greater magnetic field amplitudes for motor-evoked activity were found for the unoperated limb. Topographical maps revealed significantly different regions of activation supporting the movements for each side. Conclusions MEG was used successfully to investigate the relative inter-hemispheric differences for motor processing in clinical amyoplasia. Observed differences suggests that MEG may be a promising approach to provide additional diagnosis to understand different etiologies aimed at supporting recovery.