Exercise combined with electrical stimulation for the treatment of chronic ankle instability - A randomized controlled trial

PURPOSE

To compare the short, medium, and long-term effects of balance exercises combined with either peroneal neuromuscular electrical stimulation (NMES) or peroneal transcutaneous electrical nerve stimulation (TENS) on dynamic postural control and patient reported outcome measures (PROMs) in patients with chronic ankle instability (CAI).

METHODS

Thirty-four participants with CAI were randomly assigned to a 12-session home based exercise program combined with NMES (Ex-NMES) or TENS (Ex- TENS). Baseline postural control was tested with the modified Star Excursion Balance Test (mSEBT) and time to stabilization (TTS) after a single-leg drop-jump. The self-reported function was measured using the Cumberland Ankle Instability Tool (CAIT), the Identification of Functional Ankle Instability (IdFAI), and the Sports subscale of the Foot and Ankle Ability Measure (FAAMSport).

RESULTS

Both groups showed significant improvements in all self-reported outcome measures at the 12-month follow-up. Subjects in the Ex-NMES group had significantly better IdFAI (-4.2 [95% CI -8.1, -0.2]) and FAAMSport (13.7 [95% CI 2.2, 25.2]) scores at 6- and 12-month follow-up, respectively, compared to the Ex-TENS group. Medium to large between-group effect sizes were observed in self-reported functional outcomes and the mSEBT.

CONCLUSION

The consistent trend of improvement in self-reported functional outcomes when training is combined with NMES compared with training with TENS may indicate a potential benefit that should be further investigated as a treatment for patients with CAI.

Peroneal muscle response to single-leg drop-jump and unexpected leg-drop in young and middle-aged adults before and after one session of neuromuscular training

BACKGROUND

Changes in neuromuscular ability in middle age (MA) may lead to deterioration of postural control. The aim of this study was to investigate the anticipatory response of the peroneus longus muscle (PL) to landing after a single-leg drop-jump (SLDJ), and its postural response after an unexpected leg-drop in MA and young adults. A second aim was to investigate the influence of neuromuscular training on PL postural responses in both age groups.

METHODS

Twenty-six healthy MA (55.3 ± 4 years) and 26 healthy young adults (26.3 ± 3.6 years) participated in the study. Assessments were performed before (T0) and after (T1) PL EMG biofeedback (BF) neuromuscular training. Subjects performed SLDJ, and PL EMG activity in preparation for landing (% of flight time) was calculated. To measure PL time to activation onset and time to peak activation in response to an unexpected leg-drop, subjects stood on a customized trapdoor device that produced a sudden 30° ankle inversion.

RESULTS

Before training, the MA group showed significantly shorter PL activity in preparation for landing compared to the young adults (25.0% vs. 30.0%, p = 0.016), while after training there was no difference between the groups (28.0% vs. 29.0%, p = 0.387). There were no differences between groups in peroneal activity after the unexpected leg-drop before and after training.

CONCLUSIONS

Our results suggest that automatic anticipatory peroneal postural responses are decreased at MA, whereas reflexive postural responses appear to be intact in this age group. A short PL EMG-BF neuromuscular training may have an immediate positive effect on PL muscle activity at MA. This should encourage the development of specific interventions to ensure better postural control in this group.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05006547.

Self-Reported Questionnaire to Evaluate Functional Abilities in Middle Age: A Call for Delphi Expert Panel

Early detection of functional decline is important for promoting optimal aging. Self-reported questionnaires can efficiently assess functional abilities. Therefore, we aimed to highlight the lack of functional ability assessment questionnaires for the middle-aged population (MA, 45-65 years) and the need to develop such a questionnaire. An online search was performed to find questionnaires quantifying self-reported performance and functional abilities at MA. We also conducted an online survey of a group of the MA population and interviewed individuals who reported age-related functional decline. Eight potentially relevant questionnaires were found, and one hundred and twenty-three individuals responded to our survey, five of whom were interviewed. None of the questionnaires were specifically designed to assess functional capacity at MA, and most of the questionnaires are likely to have a ceiling effect in assessing the MA population. Furthermore, the questionnaires do not capture functions related to dynamic balance, flexibility, and maximum strength, which are reported as difficult by our respondents, making them less appropriate for assessing function at MA. There is a need to engage a Delphi expert panel of several relevant healthcare professionals to develop a functional capacity assessment questionnaire for MA.

Young, but not in the dark-The influence of reduced lighting on gait stability in middle-aged adults

BACKGROUND

The aim of this study was to investigate the effects of walking in reduced lighting with or without performing a secondary cognitive task on gait dynamics in middle-aged adults and to compare them with young and old adults.

METHODS

Twenty young (age 28.8±4.1), 20 middle-aged (age 50.2±4.4), and 19 elderly (age 70.7±4.2) subjects participated in the study. Subjects walked on an instrumented treadmill at a self-determined pace under four conditions in randomized order: (1) walking in usual lighting (1000 lumens); (2) walking in near-darkness (5 lumens); (3) walking in usual lighting with a serial-7 subtraction dual-task; and (4) walking in near-darkness with a serial-7 subtraction dual-task. Variability in stride time and variability in the trajectory of the center of pressure in the sagittal and frontal planes (anterior/posterior and lateral variability) were measured. Repeated measures ANOVA and planned comparisons were used to determine the effects of age, lighting conditions, and cognitive task on each gait outcome.

RESULTS

Under usual lighting, stride time variability and anterior/posterior variability of the middle-aged subjects were similar to those of the young and lower than those of the old. The lateral variability of the middle-aged subjects was higher than that of young adults under both lighting conditions. Similar to the older adults, the middle-aged participants increased their stride time variability when walking in near-darkness, but they were the only ones to exhibit increased lateral variability and anterior/posterior variability in near-darkness. Young adult gait was not affected by lighting, and concurrent performance of a cognitive task while walking did not affect gait stability in all groups under any of the lighting conditions.

CONCLUSIONS

Gait stability decreases in middle age when walking in the dark. Recognition of functional deficits in middle age could promote appropriate interventions to optimize aging and reduce fall risk.

Can stabilization analysis following a single leg drop jump be compared between young and middle-aged adults

We aimed to verify whether the computational approaches previously proposed to analyze stability after a single-leg drop-jump (SLDJ) could be applied to a population of middle-aged adults. Fifteen middle-aged (56.4 ± 4.6 years) and 15 young adults (26.7 ± 3.9 years) performed five SLDJs. Stabilization measurements included (1) time to stabilization (TTS) based on vertical ground reaction force (GRF) (TTSv) and a fixed stabilization threshold; (2) TTS based on medio-lateral GRF (TTSml) using five different methods to preprocess the signal and stabilization threshold; (3) early medio-lateral stabilization- the averaged absolute values of the GRF in 0.2-1.4 s post-landing; (4) late medio-lateral stabilization - the averaged absolute values of the GRF at 1 s-5 s after landing. TTSv showed longer TTS values in middle-aged participants. In addition, middle-aged adults showed greater sway in late stabilization. However, TTSml values varied considerably between calculation methods, and early stabilization showed no significant differences between groups except in the first 0.2 s after landing. The results of the current study suggest that TTS calculations are sensitive to signal and threshold selection, and to the processing method. Calculations based on a fixed threshold are more appropriate for studying dynamic postural stability in middle age. With appropriate method selection, a decreased stabilizing performance can be demonstrated in middle-aged adults compared to young adults.

A practical approach to incidental findings in neuroimaging research

OBJECTIVE

We describe the systematic approach to incidental findings (IFs) used at the Mind Research Network (MRN) where all MRI scans receive neuroradiologist interpretation and participants are provided results.

METHODS

From 2004 to 2011, 8,545 MRI scans were acquired by 45 researchers. As mandated by MRN's external institutional review board, all structural sequences were evaluated by a clinical neuroradiologist who generated a report that included recommendations for referral if indicated. Investigators received a copy of their participants' reports, which were also mailed to participants unless they specifically declined. To better understand the impact of the radiology review process, a financial analysis was completed in addition to a follow-up phone survey to characterize participant perceptions regarding receiving their MRI scan results.

RESULTS

The radiologist identified IFs in 34% of the 4,447 participants. Of those with IFs (n = 1,518), the radiologist recommended urgent or immediate referral for 2.5% and routine referral for 17%. For 80.5%, no referral was recommended. Estimated annual cost for this approach including support for the neuroradiologist, medical director, and ancillary staff is approximately $60,000 or $24/scan. The results of the retrospective phone survey showed that 92% of participants appreciated receiving their MRI report, and the majority stated it increased their likelihood of volunteering for future studies.

CONCLUSIONS

Addressing IFs in a cost-effective and consistent manner is possible by adopting a policy that provides neuroradiology interpretation and offers participant assistance with clinical follow-up when necessary. Our experience suggests that an ethical, institution-wide approach to IFs can be implemented with minimal investigator burden.

Different strategies for auditory word recognition in healthy versus normal aging

To explore the effects of commonly encountered pathology on auditory recognition strategies in elderly participants, magnetoencephalographic (MEG) brain activation patterns and performance were examined in 30 elderly [18 controls and 12 elderly with mild cognitive impairment (MCI) or probable Alzheimer's disease (AD)]. It was predicted that participants with known pathology would reveal different networks of brain activation, compared to healthy elderly, which should correlate with poorer performance. Participants heard a list of words representing common objects, twice. After 20 minutes a list of new and old words was presented and participants judged whether each word was heard earlier. MEG responses were analyzed using a semiautomated source modeling procedure. A cluster analysis using all subjects' MEG sources revealed three dominant patterns of activity which correlated with IQ and task performance. The highest performing group revealed activity in premotor, anterior temporal, and superior parietal lobes with little contribution from prefrontal cortex. Performance and brain activation patterns were also compared for individuals with or without abnormalities such as white matter hyperintensities and/or volume reduction evidenced on their MRIs. Memory performance and activation patterns for individuals with white matter hyperintensities resembled the group of MCI/AD patients. These results emphasize the following: (1) general pathology correlates with cognitive decline and (2) full characterization of the health of elderly participants is important in studies of normal aging since random samples from the elderly population are apt to include individuals with subclinical pathology that can affect cognitive performance.

Fluororuby as a marker for detection of acute axonal injury in rat spinal cord

Axonal damage is a common pathological consequence of spinal cord injury. Previous studies have detected axonal injury with silver stains for degeneration or immunohistochemistry for alterations in components such as beta-amyloid precursor protein, neurofilament or ubiquitin. Fluororuby has recently been introduced as a neuronal tracer in studies of spinal cord injury and regeneration. Our study was carried out to determine whether Fluororuby can be used to identify injured axons and monitor the time course of axonal damage. Adult rats underwent needle puncture injury to the white matter in the midline and lateral spinal cord at T11. At the same time, 0.05 microl of Fluororuby was injected into the cord at the same sites. After survival times ranging from 6 h to 3 weeks, spinal cords were cut into longitudinal frozen sections and examined with confocal microscopy. Fluororuby was found to label key features of axonal injury including axonal swelling, retraction balls and disrupted axons. Damaged axons close to the injury site were consistently labeled within 6 h, with indications of swollen and disconnected axons spreading further from the site during the first week. Fewer injured axons were labeled after 1 week survival, but the marker revealed longer distances of degenerating axons both distal and rostral to the injury site. Our findings indicate that Fluororuby is a quick, sensitive, reliable and technically simple fluorescent marker for early stages of acute axonal injury and degeneration.

A biologically motivated solution to the cocktail party problem

We present a new approach to the cocktail party problem that uses a cortronic artificial neural network architecture (Hecht-Nielsen, 1998) as the front end of a speech processing system. Our approach is novel in three important respects. First, our method assumes and exploits detailed knowledge of the signals we wish to attend to in the cocktail party environment. Second, our goal is to provide preprocessing in advance of a pattern recognition system rather than to separate one or more of the mixed sources explicitly. Third, the neural network model we employ is more biologically feasible than are most other approaches to the cocktail party problem. Although the focus here is on the cocktail party problem, the method presented in this study can be applied to other areas of information processing.

A cervical manikin procedure for chiropractic skills development

OBJECTIVE

To determine whether chiropractic students can effectively acquire adjustive skills for the cervical spine by utilizing a Thrust in Motion Cervical (TMC) manikin and to evaluate its value as a teaching aid. A pilot study was formulated and incorporated into the skills tutorial program at Macquarie University. Centre for Chiropractic in Sydney, Australia.

DESIGN AND SETTING

A prospective study was performed on chiropractic students with no prior experience in performing spinal adjustments.

SUBJECTS

Twenty subjects were selected randomly from a population of 75 students about to commence their 4th-yr Master's of Chiropractic program.

INTERVENTION

Students who formed the experimental group (n = 6) did not perform any thrusting maneuvers on human subjects while practicing Diversified chiropractic cervical spinal techniques. They practiced the adjustive thrust only on the TMC manikin. The control group (n = 14) learned in the established "hands-on" approach, performing thrusting maneuvers on fellow student subjects. Both groups were supervised, taught and examined in an otherwise identical fashion.

RESULTS

The data indicate there is no significant difference between the examination scores of the student group that practiced on the TMC manikin (average, 2.17 points) compared with the controls (2.13 points), with a confidence interval at p = .985, assuming that 0.5 marks is clinically important in these examination results. Interexam reliability was acceptable (Pearson's r = .73) for both experimental and control examination performances.

CONCLUSION

The null hypothesis is accepted, and no significant difference in student examination performance was found between those who learned thrusting on the manikin alone and those who learned on fellow students. Further, for the first time, a manikin has been shown to be effective in teaching chiropractic skills. The implications of the TMC manikin procedure will revolutionize the acquisition of motor learning skills that are essential for chiropractic skills training.