Tinnitus reduction after active bone-conduction implantation in patients with single-sided deafness: a prospective multicenter study.

PURPOSE: Single-sided deafness (SSD) presents significant challenges for patients, including compromised sound localization, reduced speech recognition, and often, tinnitus. These issues are typically addressed using interventions such as cochlear implantation (CI) and bone conduction implant (BCI). However, evidence regarding the efficacy of BCI in reducing tinnitus in SSD patients remains limited. This study explored the ability of a novel active transcutaneous BCI (Bonebridge BCI602) to alleviate tinnitus in SSD patients. STUDY DESIGN: Prospective cohort multicenter study. SETTING: Tertiary referral hospitals. METHODS: A prospective multicenter study of 30 SSD patients was conducted. The patients were divided into two groups: those with (n = 19) and without (n = 11) tinnitus. Audiometric assessments, subjective questionnaires including the Abbreviated Profile of Hearing Aid Benefit (APHAB) and the Bern Benefit in Single-Sided Deafness (BBSS), and tinnitus evaluations with the Tinnitus Handicap Inventory (THI) and tinnitogram were conducted before and after BCI surgery. RESULTS: THI scores after surgery were significantly reduced in SSD patients with tinnitus. Subjective satisfaction improved in both the tinnitus and non-tinnitus groups; however, the former group exhibited a significantly greater improvement in the APHAB questionnaire score. According to tinnitograms, the loudness of tinnitus decreased, particularly in patients with ipsilateral tinnitus. Patients with residual hearing had greater reductions in their THI scores. However, three patients without residual hearing had a relative worsening of tinnitus after surgery. CONCLUSION: The Bonebridge BCI602 effectively reduced tinnitus in SSD patients, particularly in those with residual hearing. Subjective satisfaction improved in both the tinnitus and non-tinnitus groups. These findings demonstrate the therapeutic potential of BCI for managing SSD and associated tinnitus.

Efficacy of the Bonebridge BCI602 for Adult Patients with Single-sided Deafness: A Prospective Multicenter Study.

OBJECTIVE: To investigate the safety and efficacy of a novel active transcutaneous bone conduction implant (BCI) device for patients with single-sided deafness (SSD). STUDY DESIGN: Prospective cohort study. SETTING: Tertiary referral hospitals. METHODS: This prospective multicenter study was conducted at 15 institutions nationwide. Thirty adult (aged ≥19 years) SSD patients were recruited. They underwent implantation of an active transcutaneous BCI device (Bonebridge BCI602). Objective outcomes included aided pure-tone thresholds, aided speech discrimination scores (SDSs), and the Hearing in Noise Test (HINT) and sound localization test results. The Bern Benefit in Single-Sided Deafness (BBSS) questionnaire, the Abbreviated Profile of Hearing Aid Benefit (APHAB) questionnaire, and the Tinnitus Handicap Inventory (THI) were used to measure subjective benefits. RESULTS: The mean aided pure-tone threshold was 34.2 (11.3), mean (SD), dB HL at 500 to 4000 Hz. The mean total BBSS score was 27.5 (13.8). All APHAB questionnaire domain scores showed significant improvements: ease of communication, 33.6 (23.2) versus 22.6 (21.3), P = .025; reverberation, 44.8 (16.6) versus 32.8 (15.9), P = .002; background noise, 55.5 (23.6) versus 35.2 (18.1), P < .001; and aversiveness, 36.7 (22.8) versus 25.8 (21.4), P = .028. Moreover, the THI scores were significantly reduced [47.4 (30.1) versus 31.1 (27.0), P = .003]. Congenital SSD was a significant factor of subjective benefit (-11.643; 95% confidence interval: -21.946 to -1.340). CONCLUSION: The BCI602 active transcutaneous BCI device can provide functional hearing gain without any adverse effects and is a feasible option for acquired SSD patients with long-term deafness.

Characterizing neurological status in individuals with tetraplegia using transcutaneous spinal stimulation.

Transcutaneous spinal stimulation (TSS) is emerging as a valuable tool for electrophysiological and clinical assessment. This study had the objective of examining the recruitment patterns of upper limb (UL) motor pools through the delivery of TSS above and below a spinal lesion. It also aimed to explore the connection between the recruitment pattern of UL motor pools and the neurological and functional status following spinal cord injury (SCI). In eight participants with tetraplegia due to cervical SCI, TSS was delivered to the cervical spinal cord between the spinous processes of C3-C4 and C7-T1 vertebrae, and spinally evoked motor potentials in UL muscles were characterized. We found that responses observed in UL muscles innervated by motor pools below the level of injury demonstrated relatively reduced sensitivity to TSS compared to those above the lesion, were asymmetrical in the majority of muscles, and were dependent on the level, extent, and side of SCI. Overall, our findings indicate that electrophysiological data acquired through TSS can offer insights into the extent of UL functional asymmetry, disruptions in neural pathways, and changes in motor control following SCI. This study suggests that such electrophysiological data can supplement clinical and functional assessment and provide further insight regarding residual motor function in individuals with SCI.

Transcutaneous spinal stimulation provides characterization of neurological status in individuals with tetraplegia.

Transcutaneous spinal stimulation (TSS) is emerging as a valuable tool for electrophysiological and clinical assessment. This study had the objective of examining the recruitment patterns of upper limb (UL) motor pools through the delivery of TSS above and below a spinal lesion. It also aimed to explore the connection between the recruitment pattern of UL motor pools and the neurological and functional status following spinal cord injury (SCI). In eight participants with tetraplegia due to cervical SCI, TSS was delivered to the cervical spinal cord between the spinous processes of C3-C4 and C7-T1 vertebrae, and spinally evoked motor potentials in UL muscles were characterized. We found that responses observed in UL muscles innervated by motor pools below the level of injury demonstrated relatively reduced sensitivity to TSS compared to those above the lesion, were asymmetrical in the majority of muscles, and were dependent on the level, extent, and side of SCI. Overall, our findings indicate that electrophysiological data acquired through TSS can offer insights into the extent of UL functional asymmetry, disruptions in neural pathways, and changes in motor control following SCI. This study suggests that such electrophysiological data can supplement clinical and functional assessment and provide further insight regarding residual motor function in individuals with SCI.

Trunk and lower extremity biomechanics differ between female athletes with and without a concussion history.

CONTEXT: Athletes with a history of concussion are at a greater risk for lower extremity musculoskeletal injury. Female athletes may be at an even greater risk. Previous landing biomechanics research post-concussion has focused on the lower extremities, but the trunk plays a crucial role as an injury risk factor. OBJECTIVE: To compare lower extremity and trunk biomechanics during jump landing and cutting maneuvers between female athletes with and without a concussion history. DESIGN: Cross-sectional. SETTING: Biomechanics laboratory. PARTICIPANTS: Our study included 26 athletes with (age:19.0±1.3years, BMI:22.6±2.0kg/m2, time since most recent concussion: median=37.5 months [interquartile range (25.0, 65.8)]), and 38 athletes without (age:19.0±1.1years, BMI:22.1±1.8kg/m2) a concussion history. MAIN OUTCOME MEASURES: Peak kinetics (vertical ground reaction force, vertical loading rate, external knee abduction moment, external knee flexion moment) and kinematics (trunk flexion angle, trunk lateral bending angle, dorsiflexion angle, knee flexion angle, knee abduction angle, hip flexion angle) were obtained during the eccentric portion of the task. Separate 2 (group) × 2 (limb) between-within analyses of covariance compared outcomes between groups. We covaried for time since most recent concussion and limb which had a history of musculoskeletal injury. RESULTS: Athletes with a concussion history displayed a greater nondominant knee abduction angle compared to their dominant limb (p=0.010, np2=0.107) and athletes without a concussion history nondominant limb (p=0.023, np2=0.083) during the jump landing. Athletes with a concussion history displayed less trunk lateral bending during cutting compared with athletes without a concussion history (p=0.005, np2=0.126). CONCLUSIONS: Our results indicate landing biomechanics are different between female athletes with and without a concussion history. This may be due to impairments in neuromuscular control post-concussion which may ultimately increase the risk of subsequent lower extremity injury, although further research is warranted given the cross-sectional nature of our study.

Computerized and functional reaction time in varsity-level female collegiate athletes with and without a concussion history.

OBJECTIVES: To 1) determine the association between computerized and functional reaction time, and 2) compare functional reaction times between female athletes with and without a concussion history. DESIGN: Cross-sectional study. METHODS: Twenty female college athletes with concussion history (age = 19.1 ±â€¯1.5 years, height = 166.9 ±â€¯6.7 cm, mass = 62.8 ±â€¯6.9 kg, median total concussion = 1.0 [interquartile range = 1.0, 2.0]), and 28 female college athletes without concussion history (age = 19.1 ±â€¯1.0 years, height = 172.7 ±â€¯8.3 cm, mass = 65.4 ±â€¯8.4 kg). Functional reaction time was assessed during jump landing and dominant and non-dominant limb cutting. Computerized assessments included simple, complex, Stroop, and composite reaction times. Partial correlations investigated the associations between functional and computerized reaction time assessments while covarying for time between computerized and functional reaction time assessments. Analysis of covariance compared functional and computerized reaction time, covarying for time since concussion. RESULTS: There were no significant correlations between functional and computerized reaction time assessments (p-range = 0.318 to 0.999, partial correlation range = -0.149 to 0.072). Reaction time did not differ between groups during any functional (p-range = 0.057 to 0.920) or computerized (p-range = 0.605 to 0.860) reaction time assessments. CONCLUSIONS: Post-concussion reaction time is commonly assessed via computerized measures, but our data suggest computerized reaction time assessments are not characterizing reaction time during sport-like movements in varsity-level female athletes. Future research should investigate confounding factors of functional reaction time.

Jump Height and Hip Power Decrease During Cognitive Loading Regardless of Sex: Implications for Sport Performance Metrics.

ABSTRACT: Shumski, EJ, Lempke, LB, Johnson, RS, Oh, J, Schmidt, JD, and Lynall, RC. Jump height and hip power decrease during cognitive loading regardless of sex: implications for sport performance metrics. J Strength Cond Res 37(4): 793-798, 2023-Sex and cognitive loading separately influence jumping performance. However, it is unknown how cognitive loading influences jump performance and how sex and cognitive loading interact. The purpose of our study was to determine if an interaction existed between sex and cognitive loading for the dependent variables jump height, ground contact time, reactive strength index, vertical stiffness, impulse, and lower extremity joint power during a double limb drop vertical jump. Twenty-one male (23.2 ± 2.5 years, 180.8 ± 8.4 cm, 80.4 ± 10.2 kg) and 20 female (21.7 ± 1.0 years, 163.7 ± 8.2 cm, 61.2 ± 9.4 kg) physically active individuals participated. Subjects jumped from a 30 cm box placed 50% of their height away from 2 force plates under single-task and dual-task (serial 6s or 7s) conditions. Separate 2 × 2 analyses of variance were used for all dependent variables (α = 0.05) with Bonferroni post hoc mean differences and 95% confidence intervals (CIs). There were no significant interactions for any outcomes ( p ≥ 0.190). Condition main effects demonstrated subjects jumped significantly higher (1.84 cm, 95% CI = 0.68-3.01, d = 0.26, p = 0.003) and with greater hip power (0.29 Watts·BW -1 ·HT -1 , 95% CI = 0.04-0.54, d = 0.21, p = 0.025) during single task compared with dual task. Sex main effects revealed males jumped higher (9.88 cm, 95% CI = 7.00-12.77, d = 2.17, p < 0.001), with greater reactive strength index (0.29, 95% CI = 0.17-0.41, d = 1.52, p < 0.001), greater ankle power (3.70 Watts·BW -1 ·HT -1 , 95% CI = 2.26-5.13, d = 1.64, p < 0.001), and greater knee power (5.00 Watts·BW -1 ·HT -1 , 95% CI = 3.25-6.75, d = 1.82, p < 0.001) compared with females. Jump performance is influenced by sex and dual-task conditions but not their interaction. To optimize jumping performance, testing should be completed without distractions (single task) to decrease cognitive loading.

Combinatorial Effects of Transcutaneous Spinal Stimulation and Task-Specific Training to Enhance Hand Motor Output after Paralysis.

Background: Despite the positive results in upper limb (UL) motor recovery after using electrical neuromodulation in individuals after cervical spinal cord injury (SCI) or stroke, there has been limited exploration of potential benefits of combining task-specific hand grip training with transcutaneous electrical spinal stimulation (TSS) for individuals with UL paralysis. Objectives: This study investigates the combinatorial effects of task-specific hand grip training and noninvasive TSS to enhance hand motor output after paralysis. Methods: Four participants with cervical SCI classified as AIS A and B and two participants with cerebral stroke were recruited in this study. The effects of cervical TSS without grip training and during training with sham stimulation were contrasted with hand grip training with TSS. TSS was applied at midline over cervical spinal cord. During hand grip training, 5 to 10 seconds of voluntary contraction were repeated at a submaximum strength for approximately 10 minutes, three days per week for 4 weeks. Signals from hand grip dynamometer along with the electromyography (EMG) activity from UL muscles were recorded and displayed as visual feedback. Results: Our case study series demonstrated that combined task-specific hand grip training and cervical TSS targeting the motor pools of distal muscles in the UL resulted in significant improvements in maximum hand grip strength. However, TSS alone or hand grip training alone showed limited effectiveness in improving grip strength. Conclusion: Task-specific hand grip training combined with TSS can result in restoration of hand motor function in paralyzed upper limbs in individuals with cervical SCI and stroke.

Measuring Torque Production with a Robotic Exoskeleton during Cervical Transcutaneous Spinal Stimulation.

Spinal cord injury (SCI) affects a large number of individuals in the United States. Unfortunately, traditional neurorehabilitation therapy leaves out clinical populations with limited motor function, such as severe stroke or spinal cord injury, as they are incapable of engaging in movement therapy. To increase the numbers of individuals who may be able to participate in robotic therapy, our long-term goal is to combine two validated interventions, transcutaneous spinal stimulation (TSS) and robotics, to elicit upper limb movements during rehabilitation following SCI. To achieve this goal, it is necessary to quantify the contributions of each intervention to realizing arm movements. Electromyography is typically used to assess the response to TSS, but the robot itself offers an additional source of data since the available sensors on the robot can be used to directly assess resultant actions of the upper limb after stimulation. We explore this approach in this paper. We showed that the effects of cutaneous TSS can be observed by measuring the holding torque required by the exoskeleton to keep a user's arm in a neutral position. Further, we can identify differences in resultant action based on the location of the stimulation electrodes with respect to the dorsal roots of the spinal cord. In the future, we can use measurements from the robot to guide the action of the robot and TSS intervention.

Cervical transcutaneous spinal stimulation for spinal motor mapping.

Transcutaneous spinal stimulation (TSS) is a promising approach to restore upper-limb (UL) functions after spinal cord injury (SCI) in humans. We sought to demonstrate the selectivity of recruitment of individual UL motor pools during cervical TSS using different electrode placements. We demonstrated that TSS delivered over the rostrocaudal and mediolateral axes of the cervical spine resulted in a preferential activation of proximal, distal, and ipsilateral UL muscles. This was revealed by changes in motor threshold intensity, maximum amplitude, and the amount of post-activation depression of the evoked responses. We propose that an arrangement of electrodes targeting specific UL motor pools may result in superior efficacy, restoring more diverse motor activities after neurological injuries and disorders, including severe SCI.

Monitoring joint mechanics in anterior cruciate ligament reconstruction using depth sensor-driven musculoskeletal modeling and statistical parametric mapping.

The incidence of anterior cruciate ligament injury and reconstruction (ACLR) may set the stage for the development of early onset osteoarthritis in these patients. Development of accessible quantitative motion capture methodologies for recurrent monitoring of knee joint loading during daily activities following ACLR is necessary. This study aimed to compare lower extremity kinetics between ACLR affected limbs, ACLR unaffected limbs, and dominant limbs of healthy control subjects during over-ground gait and stair ascent using a single depth sensor-driven musculoskeletal modeling approach. No meaningful differences were found between groups during over-ground gait in any kinetic variables. When subjected to a stair ascent task, both ACLR limbs showed greater hip extension and internal rotation moments compared to control subjects at approximately 72-79% stance. This was coincident with greater knee flexion moments in both ALCR limbs compared to control. The absence of differences during over-ground gait but presence of compensatory strategies during stair ascent, suggests task dependent recovery in this cohort who were tested at least 1-year following surgery. Importantly, this was determined using a portable low-cost motion capture method which may be attractive to professionals in sports medicine for recurrent monitoring following ACLR.

Influence of eccentric strength of knee extensor muscles on biomechanical factors of a vertical drop jump.

During a vertical drop jump (VDJ), the human neuromuscular system absorbs and reuses external loads applied to the lower extremity by coordinating the musculoskeletal system. This study aims to investigate the influence of the eccentric strength of the knee extensor muscles on the biomechanical factors of a VDJ. Participants were divided into two groups based on the eccentric strength of their knee extension muscles: low eccentric (LECC) and high eccentric (HECC) strength groups. The VDJ joint kinematics and kinetics of the lower extremity, the fascicle behavior of the vastus lateralis, and the muscle activation of the knee extensor muscles were simultaneously recorded during maximum-effort VDJ. Compared with the LECC group, the HECC group showed a higher jump, greater knee and ankle joint stiffness, and smaller fascicle length change. These findings suggest that the eccentric strength capacity of the knee extensor muscles accounts for the different biomechanical strategies (bouncing-type for HECC and absorbing-type for LECC) observed between the groups. Consequently, the eccentric strength of the knee extensor muscle may be an essential factor in determining the biomechanical strategy for VDJ and should be considered in the jumping performance enhancement training paradigm.

Characterization of interlimb interaction via transcutaneous spinal stimulation of cervical and lumbar spinal enlargements.

The use of transcutaneous electrical spinal stimulation (TSS) to modulate sensorimotor networks after neurological insult has garnered much attention from both researchers and clinicians in recent years. Although many different stimulation paradigms have been reported, the interlimb effects of these neuromodulation techniques have been little studied. The effects of multisite TSS on interlimb sensorimotor function are of particular interest in the context of neurorehabilitation, as these networks have been shown to be important for functional recovery after neurological insult. The present study utilized a condition-test paradigm to investigate the effects of interenlargement TSS on spinal motor excitability in both cervical and lumbosacral motor pools. Additionally, comparison was made between the conditioning effects of lumbosacral and cervical TSS and peripheral stimulation of the fibular nerve and ulnar nerve, respectively. In 16/16 supine, relaxed participants, facilitation of spinally evoked motor responses (sEMRs) in arm muscles was seen in response to lumbosacral TSS or fibular nerve stimulation, whereas facilitation of sEMRs in leg muscles was seen in response to cervical TSS or ulnar nerve stimulation. The decreased latency between TSS- and peripheral nerve-evoked conditioning implicates interlimb networks in the observed facilitation of motor output. The results demonstrate the ability of multisite TSS to engage interlimb networks, resulting in the bidirectional influence of cervical and lumbosacral motor output. The engagement of interlimb networks via TSS of the cervical and lumbosacral enlargements represents a feasible method for engaging spinal sensorimotor networks in clinical populations with compromised motor function.NEW & NOTEWORTHY Bidirectional interlimb modulation of spinal motor excitability can be evoked by transcutaneous spinal stimulation over the cervical and lumbosacral enlargements. Multisite transcutaneous spinal stimulation engages spinal sensorimotor networks thought to be important in the recovery of function after spinal cord injury.

Characterization of Spinal Sensorimotor Network Using Transcutaneous Spinal Stimulation during Voluntary Movement Preparation and Performance.

Transcutaneous electrical spinal stimulation (TSS) can be used to selectively activate motor pools based on their anatomical arrangements in the lumbosacral enlargement. These spatial patterns of spinal motor activation may have important clinical implications, especially when there is a need to target specific muscle groups. However, our understanding of the net effects and interplay between the motor pools projecting to agonist and antagonist muscles during the preparation and performance of voluntary movements is still limited. The present study was designed to systematically investigate and differentiate the multi-segmental convergence of supraspinal inputs on the lumbosacral neural network before and during the execution of voluntary leg movements in neurologically intact participants. During the experiments, participants (N = 13) performed isometric (1) knee flexion and (2) extension, as well as (3) plantarflexion and (4) dorsiflexion. TSS consisting of a pair pulse with 50 ms interstimulus interval was delivered over the T12-L1 vertebrae during the muscle contractions, as well as within 50 to 250 ms following the auditory or tactile stimuli, to characterize the temporal profiles of net spinal motor output during movement preparation. Facilitation of evoked motor potentials in the ipsilateral agonists and contralateral antagonists emerged as early as 50 ms following the cue and increased prior to movement onset. These results suggest that the descending drive modulates the activity of the inter-neuronal circuitry within spinal sensorimotor networks in specific, functionally relevant spatiotemporal patterns, which has a direct implication for the characterization of the state of those networks in individuals with neurological conditions.

Single- Versus Dual-Task Functional Movement Paradigms: A Biomechanical Analysis.

CONTEXT: Laboratory-based movement assessments are commonly performed without cognitive stimuli (ie, single-task) despite the simultaneous cognitive processing and movement (ie, dual task) demands required during sport. Cognitive loading may critically alter human movement and be an important consideration for truly assessing functional movement and understanding injury risk in the laboratory, but limited investigations exist. OBJECTIVE: To comprehensively examine and compare kinematics and kinetics between single- and dual-task functional movement among healthy participants while controlling for sex. DESIGN: Cross-sectional study. SETTING: Laboratory. Patients (or Other Participants): Forty-one healthy, physically active participants (49% female; 22.5 ± 2.1 y; 172.5 ± 11.9 cm; 71.0 ± 13.7 kg) enrolled in and completed the study. INTERVENTION(S): All participants completed the functional movement protocol under single- and dual-task (subtracting by 6s or 7s) conditions in a randomized order. Participants jumped forward from a 30-cm tall box and performed (1) maximum vertical jump landings and (2) dominant and (3) nondominant leg, single-leg 45° cuts after landing. MAIN OUTCOME MEASURES: The authors used mixed-model analysis of variances (α = .05) to compare peak hip, knee, and ankle joint angles (degrees) and moments (N·m/BW) in the sagittal and frontal planes, and peak vertical ground reaction force (N/BW) and vertical impulse (Ns/BW) between cognitive conditions and sex. RESULTS: Dual-task resulted in greater peak vertical ground reaction force compared with single-task during jump landing (mean difference = 0.06 N/BW; 95% confidence interval [CI], 0.01 to 0.12; P = .025) but less force during dominant leg cutting (mean difference = -0.08 N/BW; 95% CI, -0.14 to -0.02; P = .015). Less hip-flexion torque occurred during dual task than single task (mean difference = -0.09 N/BW; 95% CI, -0.17 to -0.02). No other outcomes were different between single and dual task (P ≥ .053). CONCLUSIONS: Slight, but potentially important, kinematic and kinetic differences were observed between single- and dual-task that may have implications for functional movement assessments and injury risk research. More research examining how various cognitive and movement tasks interact to alter functional movement among pathological populations is warranted before clinical implementation.

Estimation of ground reaction forces during stair climbing in patients with ACL reconstruction using a depth sensor-driven musculoskeletal model.

BACKGROUND: Although stair ambulation should be included in the rehabilitation of the long-term effects of ACL injury on knee function, the assessment of kinetic parameter in the situation where stair gait can only be established using costly and cumbersome force platforms via conventional inverse dynamic analysis. Therefore, there is a need to develop a practical laboratory setup as an assessment tool of the stair gait abnormalities in lower extremity that arise from an ACL deficiency. RESEARCH QUESTION: Can the use of a single depth sensor-driven full-body musculoskeletal gait model be considered an accurate assessment tool of the ground reaction forces (GRFs) during stair climbing for patients following ACL reconstruction (ACLR) surgery? METHODS: A total of 15 patients who underwent ACLR participated in this study. GRFs data during stair climbing was collected using a custom-built 3-step staircase with two embedded force platforms. A single depth sensor, commercially available and cost effective, was used to obtain participants' depth map information to extract the full-body skeleton information. The AnyBody TM GaitFullBody model was utilized to estimate GRFs attained by 25 artificial muscle-like actuators placed under each foot. Mean differences between the measured and estimated GRFs were compared using paired samples t-tests. The ensemble curves of the GRFs were compared between both approaches during stance phase of the gait cycle. RESULTS: The findings of this study showed that the estimation of the GRFs produced during staircase gait using a depth sensor-driven musculoskeletal model can produce acceptable results when compared to the traditional inverse dynamics modelling approach as an alternative tool in clinical settings for individuals who had undergone ACLR. SIGNIFICANCE: The introduced approach of full-body musculoskeletal modelling driven by a single depth sensor has the potential to be a cost-effective stair gait analysis tool for patients with ACL injury.

Current Treatments for Congenital Aural Atresia.

Congenital aural atresia is an ear malformation evident at birth, involving various degrees of failed external ear canal development. A true external ear canal is desirable, as devices that replace the canal are inconvenient and expensive. Therefore, an optimal surgical technique is required. Here, we review useful preoperative and operative techniques. Surgical correction is often not the preferred treatment; the hearing outcome is no better than the outcomes afforded by bone-conduction devices, and surgery may be associated with recurrence or complications such as meatal stenosis. Preoperative evaluation and appropriate management are important. Several means of preventing meatal stenosis are discussed in this review.

The Development of a Regression Model to Predict Object Transfer Power in Older Adults.

Castillo, DC, Strand, KL, Oh, J, Eltoukhy, M, Totillo, MC, and Signorile, JF. The development of a regression model to predict object transfer power in older adults. J Strength Cond Res 34(11): 3086-3093, 2020-Declines in mechanical power affect independence in older adults; however, no practical clinical method exists to assess peak power (PP) and average power (AP) during transfer tasks in this population. Therefore, predictive models were developed and validated during performance of an existing transfer assessment, the gallon-jug shelf-transfer (GJST) test. Twenty-one independent-living older women (age = 74.8 ± 5.6) and men (age = 73.8 ± 4.5) participated in the development phase. Peak power and AP were computed using data from three-dimensional movement analyses while subjects moved five 1-gallon jugs from a low (0.59 m) to high shelf (1.43 m) as quickly as possible. Stepwise linear regression models using test duration, subject height, and age produced equations with high R values for PP (0.655-0.701; p < 0.0001) and AP (0.703-0.759; p < 0.0001). However, regression and Bland-Altman analyses showed models with declining agreement as power values increased. Therefore, analyses were repeated using a quadratic model, showing stronger predictive capacity (PP: R = 0.786; AP: R = 0.878; p < 0.0001). Validity of this model was evaluated in a second sample of 30 older women (age = 69.9 ± 4.7) and men (age = 70.7 ± 4.3). Computed GJST AP and PP were compared with power produced during dominant arm chest press and distance during the seated medicine ball throw. Generalizability of these models was also confirmed through cross-validation analyses. Our results indicate mechanical power in older adults can be accurately measured using the quadratic model, with test duration as the independent variable. This model provides a simple, safe, and inexpensive assessment tool that can be administered by clinicians to improve diagnostic and therapeutic processes in older persons.

Effects of Plasma Damage Removal on Direct Contact Resistance and Hot-Electron-Induced Punch Through (HEIP) of PMOSFETs.

In order to reduce contact resistance (Rc) of the source/drain region in nanoscale devices, it is essential to overcome the increasing leakage and hot-electron-induced punch through (HEIP) degradation. In this paper, we propose a simple in situ Si soft treatment technique immediately after direct contact (DC) etching to reduce Rc and minimize HEIP degradation. We found by analysis with a transmission electron microscope, that 10 s of treatment reduced the plasma damaged layer by 19%, which resulted in 10.5% reduction of the P+ contact resistance. For comparison, the P + Rc was reduced by 6.5% when the doping level of the plug implantation was increased by 25%, but the HEIP breakdown voltage (VHEIP) by AC stress was greatly reduced by more than 80 mV, increasing the standby leakage current of DRAM devices. In the case of removing the plasma damage layer, not only did VHIEP not decrease until after 10 s, but also the reduction in Rc was larger than with the plug enhancement. The effect of the plasma damaged layer on HEIP was verified through the plug effect and gate induced drain leakage measurement, based on the distance between the gate and DC for each process. This simple in situ technique not only removed byproducts and the plasma damaged amorphous layer, but it also affected the effective implantation of dopants in subsequent plug processes. It was also cost effective because the process time was short and no extra process steps were added.

Stroboscopic Vision as a Dynamic Sensory Reweighting Alternative to the Sensory Organization Test.

CONTEXT: The sensory organization test (SOT) is a standard for quantifying sensory dependence via sway-referenced conditions (sway-referenced support and sway-referenced vision [SRV]). However, the SOT is limited to expensive equipment. Thus, a practical version of the SOT is more commonly employed-the clinical test for sensory integration in balance; however, it fails to induce postural instability to the level of SRV. OBJECTIVE: Determine if Stroboscopic vision (SV), characterized by intermittent visual blocking, may provide an alternative to the SRV for assessing postural stability. DESIGN: Descriptive laboratory study. SETTING: Research laboratory. PARTICIPANTS: Eighteen participants (9 males, 9 females; age = 22.1 [2.1] y, height = 169.8 [8.5] cm, weight = 66.5 [10.6] kg). INTERVENTION: Participants completed the SOT conditions, and then repeated SOT conditions 2 and 5 with SV created by specialized eyewear. MAIN OUTCOME MEASURES: A repeated-measures analysis of variance was completed on the time-to-boundary metrics of center-of-pressure excursion in the anteroposterior and mediolateral directions in order to determine the difference between the full-vision, SV, and SRV conditions. RESULTS: Postural stability with either SRV or SV was significantly worse than with full vision (P < .05), with no significant difference between SV and SRV (P > .05). Limits of agreement analysis revealed similar effects of SV and SRV except for unstable surface mediolateral time-to-boundary. CONCLUSIONS: In general, SV was found to induce a degree of postural instability similar to that induced by SRV, indicating that SV could be a portable and relatively inexpensive alternative for the assessment of sensory dependence and reweighting.