Functional connectivity of motor cortical network in patients with brachial plexus avulsion injury after contralateral cervical nerve transfer: a resting-state fMRI study

Abstract

IntroductionThe purpose of this study is to assess the functional connectivity of the motor cortical network in patients with brachial plexus avulsion injury (BPAI) after contralateral C7 nerve transfer, using resting-state functional magnetic resonance imaging (RS-fMRI).MethodsTwelve patients with total brachial plexus root avulsion underwent RS-fMRI after contralateral C7 nerve transfer. Seventeen healthy volunteers were also included in this fMRI study as controls. The hand motor seed regions were defined as region of interests in the bilateral hemispheres. The seed-based functional connectivity was calculated in all the subjects. Differences in functional connectivity of the motor cortical network between patients and healthy controls were compared.ResultsThe inter-hemispheric functional connectivity of the M1 areas was increased in patients with BPAI compared with the controls. The inter-hemispheric functional connectivity between the supplementary motor areas was reduced bilaterally.ConclusionsThe resting-state inter-hemispheric functional connectivity of the bilateral M1 areas is altered in patients after contralateral C7 nerve transfer, suggesting a functional reorganization of cerebral cortex.Electronic supplementary materialThe online version of this article (doi:10.1007/s00234-017-1796-0) contains supplementary material, which is available to authorized users.

A magnetoencephalographic study of longitudinal brain function alterations following carpal tunnel release

“…Furthermore, transhemispheric transposition of activated brain cortices is associated with the recovery of motor and sensory functions in ipsilesional upper limbs in patients with contralateral cervical 7 nerve transfer 21 . Resting-state MRI showed that interhemispheric functional connectivity of the primary motor cortex increased and the inter-hemispheric functional connectivity between the supplementary motor areas reduced bilaterally in patients with CTS 22 . However, these studies reveal brain function after treatment.…”

“…Several studies on brain function changes after other orthopedic surgeries have been performed 20–22 . Changes in the brain following contralateral cervical 7 nerve transfer for brachial plexus injury have been reported 21,22 .…”

“…Several studies on brain function changes after other orthopedic surgeries have been performed 20–22 . Changes in the brain following contralateral cervical 7 nerve transfer for brachial plexus injury have been reported 21,22 . Furthermore, transhemispheric transposition of activated brain cortices is associated with the recovery of motor and sensory functions in ipsilesional upper limbs in patients with contralateral cervical 7 nerve transfer 21 .…”

Administration of Curcumin Alleviates Neuropathic Pain in a Rat Model of Brachial Plexus Avulsion

“…Allodynia, elicited by a stimulus, is a noticeable feature in patients with neuropathic pain [31]. Neuropathic pain associated with BPA normally causes cold allodynia and mechanical allodynia (increased pain sensitivity) [32]. The pain states are generated and maintained by the activation of microglia and astrocytes in spinal cord, which usually lasts 3 months after BPA [33].…”

Surgery for nerve injury: current and future perspectives

“…The success of nerve transfers is largely facilitated by cortical plasticity, which has been repeatedly demonstrated in the context of nerve transfer rehabilitation. 2,41,57, 73,86 Other factors known to influence success of nerve transfer are donor size matching with the recipient nerve and the robustness of preoperative electromyography-detected activity from the donor nerve/muscle. 69,70 For example, the optimal donor-to-nerve axon count ratio for elbow flexion seems to be > 0.7:1.…”