PurposeTo compare two populations of brachial plexus palsies, one neonatal (NBPP) and the other traumatic (NNBPP) who underwent different nerve transfers, using the plasticity grading scale (PGS)... Show morePurposeTo compare two populations of brachial plexus palsies, one neonatal (NBPP) and the other traumatic (NNBPP) who underwent different nerve transfers, using the plasticity grading scale (PGS) for detecting differences in brain plasticity between both groups.MethodsTo be included, all patients had to have undergone a nerve transfer as the unique procedure to recover one lost function. The primary outcome was the PGS score. We also assessed patient compliance to rehabilitation using the rehabilitation quality scale (RQS). Statistical analysis of all variables was performed. A p & LE; 0.050 set as criterion for statistical significance.ResultsA total of 153 NNBPP patients and 35 NBPP babies (with 38 nerve transfers) met the inclusion criteria. The mean age at surgery of the NBPP group was 9 months (SD 5.42, range 4 to 23 months). The mean age of NNBPP patients was 22 years (SD 12 years, range 3 to 69). They were operated around sixth months after the trauma. All transfers performed in NBPP patients had a maximum PGS score of 4. This was not the case for the NNBPP population that reached a PGS score of 4 in approximately 20% of the cases. This difference was statistically significant (p < 0.001). The RQS was not significantly different between groups.ConclusionWe found that babies with NBPP have a significantly greater capacity for plastic rewiring than adults with NNBPP. The brain in the very young patient can process the changes induced by the peripheral nerve transfer better than in adults. Show less
Socolovsky, M.; Barillaro, K.; Bonilla, G.; Masi, G. di; Malessy, M. 2023
OBJECTIVE After brachial plexus injuries (BPIs), nerve transfers are used to restore lost muscle function. Brain plastic-ity underlies the process of regaining volitional control, which encompasses... Show moreOBJECTIVE After brachial plexus injuries (BPIs), nerve transfers are used to restore lost muscle function. Brain plastic-ity underlies the process of regaining volitional control, which encompasses disconnection of the original donor nerve-re-lated programs and reconnection to acceptor nerve programs. To the authors' knowledge, the levels of disconnection and reconnection have never been studied systematically. In this study, the authors developed a novel 4-point plasticity grad-ing scale (PGS) and assessed the degree of volitional control achieved, identifying clinical correlations with this score.METHODS Patients with BPI who underwent a phrenic, spinal accessory, median, and/or ulnar fascicle nerve transfer to restore biceps and deltoid function were asked to maximally contract their target muscle as follows: 1) by using only the donor nerve program, and 2) by activating the target muscle while consciously trying to avoid using the donor nerve, with assessment each time of the Medical Research Council (MRC) scale grade for muscle strength. The authors' PGS was used to rate the level of volitional control achieved. PGS grade 1 represented the lowest independent volitional control, with MRC grade 4 obtained in response to the donor command and MRC grade 0 in response to the acceptor command (minimum brain plasticity), whereas PGS grade 4 was no noticeable contraction in response to the donor com-mand and MRC grade 4 in response to the acceptor command (maximum brain plasticity).RESULTS In total, 153 patients were studied. For biceps restoration, the phrenic nerve was used as a donor in 44 patients, the spinal accessory nerve in 40 patients, and the median and/or ulnar fascicles in 44 patients. A triceps branch was used to restore deltoid function in 25 patients. The level of volitional control achieved was PGS grade 1 in 1 patient (0.6%), grade 2 in 21 patients (13.7%), grade 3 in 103 patients (67.3%), and grade 4 in 28 patients (18.3%). The median PGS grade did not differ significantly between the four donor nerves. No correlations were observed between age, time from BPI to surgery, duration of follow-up, or compliance with rehabilitation and PGS grade.CONCLUSIONS Just around 20% of the authors' patients developed a complete disconnection of the donor program along with complete independent control over the reinnervated muscle. Incomplete disconnection was present in the vast majority of the patients, and the level of disconnection and control was poor in approximately 15% of patients. Brain plasticity underlies patient ability to regain volitional control after a nerve transfer, but this capacity is limited. Show less
Socolovsky, M.; Malessy, M.; Bonilla, G.; Masi, G. di; Conti, M.E.; Lovaglio, A. 2019