Does age matter? The role of patient age in brain plasticity analyzed after a nerve transfer
摘要
Nerve transfers, which are increasingly applied not only for traumatic peripheral nerve injuries but also in oncologic reconstructions, spinal cord injuries, and a wide range of neurological disorders, rely heavily on the capacity of the central nervous system to reorganize and reassign motor control pathways. Among the multiple factors influencing postoperative recovery, age-dependent brain plasticity appears to play a critical role in determining the degree to which patients can regain functional control after reinnervation. This study aims to characterize this correlation in depth and to identify clinically meaningful age-related thresholds that may guide treatment planning and optimize surgical outcomes.
MethodsWe examined two patient groups who underwent a nerve transfer: (1) neonatal brachial plexus palsy (NBPP) and (2) non-neonatal brachial plexus injury (NNBPI). The Plasticity Grading Scale (PGS) was utilized to assess the degree of volitional control achieved, with scores ranging from 1 (indicating poor brain plasticity) to a maximum of 4 (indicating complete independence of movements, a sign of excellent brain plasticity). Additionally, we analyzed the relationship between age, selected nerve transfer, and PGS outcomes.
ResultsA total of 168 patients underwent nerve transfers, including 34 with NBPP and 134 with NNBPI. The median PGS scores were 4 and 3 respectively. Age was significantly associated with PGS scores in NNBPI patients receiving extra-plexual nerve transfers (p < 0.001). Optimal scores were observed in patients under 5 years of age, regardless of the donor type. In NNBPIs, intra-plexual transfers demonstrated early and sustained plasticity across all ages, whereas extra-plexual donors showed superior outcomes in patients aged 14–20, followed by a plateau after age 21.
ConclusionAge significantly impacts neural plasticity after nerve transfer. This effect is further modulated by the properties of the donor nerve and the target muscle.