Despite the importance of timing of nerve surgery after peripheral nerve injury, optimal timing of intervention has not been clearly delineated. The goal of this study is to explore factors that may have a significant impact on clinical outcomes of severe peripheral nerve injury that requires reconstruction with nerve transfer or graft.

Adult patients who underwent peripheral nerve transfer or grafting in Alberta were reviewed. Clustered multivariable logistic regression analysis was used to examine the association of time to surgery, type of nerve repair, and patient characteristics on strength outcomes. Cox proportional hazard regression analysis model was used to examine factors correlated with increased time to surgery.

Of the 163 patients identified, the median time to surgery was 212 days. For every week of delay, the adjusted odds of achieving Medical Research Council strength grade ≥ 3 decreases by 3%. An increase in preinjury comorbidities was associated with longer overall time to surgery (aHR 0.84, 95% CI 0.74–0.95). Referrals made by surgeons were associated with a shorter time to surgery compared to general practitioners (aHR 1.87, 95% CI 1.14–3.06). In patients treated with nerve transfer, the adjusted odds of achieving antigravity strength was 388% compared to nerve grafting; while the adjusted odds decreased by 65% if the injury sustained had a pre-ganglionic injury component.

Mitigating delays in surgical intervention is crucial to optimizing outcomes. The nature of initial nerve injury and surgical reconstructive techniques are additional important factors that impact postoperative outcomes.

Traumatic spinal cord injuries (tSCI) are common, often leaving patients irreparably debilitated. Therefore, novel strategies such as nerve transfers (NT) are needed for mitigating secondary SCI damage and improving function. Although different tSCI NT options exist, little is known about the epidemiological and injury-related aspects of this patient population. Here, we report such characteristics to better identify and understand the number and types of tSCI individuals who may benefit from NTs.

Two peripheral nerve experts independently evaluated all adult tSCI individuals < 80 years old admitted with cervical tSCI (C1–T1) between 2005 and 2019 with documented tSCI severity using the ASIA Impairment Scale for suitability for NT (nerve donor with MRC strength ≥ 4/5 and recipient ≤ 2/5). Demographic, traumatic injury, and neurological injury variables were collected and analyzed.

A total of 709 tSCI individuals were identified with 224 (32%) who met the selection criteria for participation based on their tSCI level (C1–T1). Of these, 108 (15% of all tSCIs and 48% of all cervical tSCIs) were deemed to be appropriate NT candidates. Due to recovery, 6 NT candidates initially deem appropriate no longer qualified by their last follow-up. Conversely, 19 individuals not initially considered appropriate then become eligible by their last follow-up.

We found that a large proportion of individuals with cervical tSCI could potentially benefit from NTs. To our knowledge, this is the first study to detail the number of tSCI individuals that may qualify for NT from a large prospective database.

Patients with bipolar disorder (BPD) are prone to engage in risk-taking behaviours and self-harm, contributing to higher risk of traumatic injuries requiring medical attention at the emergency room (ER).We hypothesize that pharmacological treatment of BPD could reduce the risk of traumatic injuries by alleviating symptoms but evidence remains unclear. This study aimed to examine the association between pharmacological treatment and the risk of ER admissions due to traumatic injuries.

Individuals with BPD who received mood stabilizers and/or antipsychotics were identified using a population-based electronic healthcare records database in Hong Kong (2001–2019). A self-controlled case series design was applied to control for time-invariant confounders.

A total of 5040 out of 14 021 adults with BPD who received pharmacological treatment and had incident ER admissions due to traumatic injuries from 2001 to 2019 were included. An increased risk of traumatic injuries was found 30 days before treatment [incidence rate ratio (IRR) 4.44 (3.71–5.31), p < 0.0001]. After treatment initiation, the risk remained increased with a smaller magnitude, before returning to baseline [IRR 0.97 (0.88–1.06), p = 0.50] during maintenance treatment. The direct comparison of the risk during treatment to that before and after treatment showed a significant decrease. After treatment cessation, the risk was increased [IRR 1.34 (1.09–1.66), p = 0.006].

This study supports the hypothesis that pharmacological treatment of BPD was associated with a lower risk of ER admissions due to traumatic injuries but an increased risk after treatment cessation. Close monitoring of symptoms relapse is recommended to clinicians and patients if treatment cessation is warranted.

Anticipatory pleasure deficits are closely correlated with negative symptoms in schizophrenia, and may be found in both clinical and subclinical populations along the psychosis continuum. Prospection, which is an important component of anticipatory pleasure, is impaired in individuals with social anhedonia (SocAnh). In this study, we examined the neural correlates of envisioning positive future events in individuals with SocAnh.

Forty-nine individuals with SocAnh and 33 matched controls were recruited to undergo functional MRI scanning, during which they were instructed to simulate positive or neutral future episodes according to cue words. Two stages of prospection were distinguished: construction and elaboration.

Reduced activation at the caudate and the precuneus when prospecting positive (v. neutral) future events was observed in individuals with SocAnh. Furthermore, compared with controls, increased functional connectivity between the caudate and the inferior occipital gyrus during positive (v. neutral) prospection was found in individuals with SocAnh. Both groups exhibited a similar pattern of brain activation for the construction v. elaboration contrast, regardless of the emotional context.

Our results provide further evidence on the neural mechanism of anticipatory pleasure deficits in subclinical individuals with SocAnh and suggest that altered cortico-striatal circuit may play a role in anticipatory pleasure deficits in these individuals.

Schizotypy refers to schizophrenia-like traits below the clinical threshold in the general population. The pathological development of schizophrenia has been postulated to evolve from the initial coexistence of ‘brain disconnection’ and ‘brain connectivity compensation’ to ‘brain connectivity decompensation’.

In this study, we examined the brain connectivity changes associated with schizotypy by combining brain white matter structural connectivity, static and dynamic functional connectivity analysis of diffusion tensor imaging data and resting-state functional magnetic resonance imaging data. A total of 87 participants with a high level of schizotypal traits and 122 control participants completed the experiment. Group differences in whole-brain white matter structural connectivity probability, static mean functional connectivity strength, dynamic functional connectivity variability and stability among 264 brain sub-regions of interests were investigated.

We found that individuals with high schizotypy exhibited increased structural connectivity probability within the task control network and within the default mode network; increased variability and decreased stability of functional connectivity within the default mode network and between the auditory network and the subcortical network; and decreased static mean functional connectivity strength mainly associated with the sensorimotor network, the default mode network and the task control network.

These findings highlight the specific changes in brain connectivity associated with schizotypy and indicate that both decompensatory and compensatory changes in structural connectivity within the default mode network and the task control network in the context of whole-brain functional disconnection may be an important neurobiological correlate in individuals with high schizotypy.

Little is known about long-term employment outcomes for patients with first-episode schizophrenia-spectrum (FES) disorders who received early intervention services.

We compared the 10-year employment trajectory of patients with FES who received early intervention services with those who received standard care. Factors differentiating the employment trajectories were explored.

Patients with FES (N = 145) who received early intervention services in Hong Kong between 1 July 2001 and 30 June 2002 were matched with those who entered standard care 1 year previously. We used hierarchical clustering analysis to explore the 10-year employment clusters for both groups. We used the mixed model test to compare cluster memberships and piecewise regression analysis to compare the employment trajectories of the two groups.

There were significantly more patients who received the early intervention service in the good employment cluster (early intervention: N = 98 [67.6%]; standard care: N = 76 [52.4%]; P = 0.009). In the poor employment cluster, there was a significant difference in the longitudinal pattern between early intervention and standard care for years 1–5 (P < 0.0001). The number of relapses during the first 3 years, months of full-time employment during the first year and years of education were significant in differentiating the clusters of the early intervention group.

Results suggest there was an overall long-term benefit of early intervention services on employment. However, the benefit was not sustained for all patients. Personalisation of the duration of the early intervention service with a focus on relapse prevention and early vocational reintegration should be considered for service enhancement.

Although electromyography (EMG), electroencephalography (EEG) and evoked potential (EP) studies are common investigation tools for patients with neurologic illnesses, no formal data on the manpower supply in Canada exists. Because of the importance of these on training requirements and future planning, the purpose of this study was to establish a comprehensive profile of the human resources situation in clinical neurophysiological services across Canada.

A questionnaire was sent to all clinical neurophysiologists in Canada. To capture the maximal number of respondents, a total of three rounds of mail out were done. In addition, to obtain accurate demographic data on supporting technologists, a separate survey was also carried out by the Association of Electrophysiological Technologists of Canada.

Of the 450 clinical neurophysiologists identified and surveyed, the provincial response rate was 59±14% (mean±SD). Of these, the vast majority practiced in urban centres. There was substantial regional disparity in different provinces. While the wait time for most EEG and EP laboratories was less than six weeks, the wait time for EMG was substantially longer. With the age of the largest number of practitioners in their sixth decade, projected retirement over the next 15 years was 58%. The demographic distribution of the supporting technologists showed a similar trend.

In addition to considerable regional disparity and urban/rural divide, a large percentage of clinical neurophysiologists and supporting technologists planned to retire within the coming decade. To ensure secure and high standard services to Canadians, solutions to fill this void are urgently needed.

The goal of this study was to compare the relative contributions from the muscle and the central nervous system to muscle fatigue resistance in aging.

Each subject carried out 90 s of sustained maximal voluntary isometric contraction (MVC) of the thumb using the thenar and forearm thumb muscles. Contractile capacity of the thenar muscles was assessed through tetanic stimulation of the median nerve. Interpolated doublets delivered during an MVC represented the overall voluntary activation level while transcranial cortical stimulation with an electromagnetic stimulator was used to assess motor output upstream from the corticomotoneuronal pathway.

Nine elderly subjects [four females and five males, 70±9 years old (mean±SD)] and 10 younger subjects (five females and five males, 30±6 years old) were tested. After the fatiguing exercise, the elderly group's MVC declined by 29% as opposed to 47% in the younger group (p<0.01). The elderly group's greater fatigue resistance was accounted for by increased fatigue resistance at the muscle level as well as in the central nervous system. At least some of the decline in the central motor drive was upstream from the corticomotoneuronal pathway.

The higher muscle fatigue resistance in the elderly group was attributable to differences in both the peripheral and central nervous systems.