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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.
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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.
Subject(s)
Sports , Humans , Male , Female , Biomechanical Phenomena , Lower Extremity , Knee Joint , CognitionABSTRACT
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.
Subject(s)
Spinal Cord Injuries , Spinal Cord Stimulation , Transcutaneous Electric Nerve Stimulation , Humans , Muscle, Skeletal/physiology , Spinal Cord/physiology , Spinal Cord Stimulation/methods , Transcutaneous Electric Nerve Stimulation/methodsABSTRACT
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.
Subject(s)
Biomechanical Phenomena/physiology , Movement/physiology , Task Performance and Analysis , Adult , Analysis of Variance , Ankle Joint/physiology , Cognition/physiology , Confidence Intervals , Female , Functional Laterality/physiology , Hip Joint/physiology , Humans , Kinetics , Knee Joint/physiology , Male , Sex Factors , Young AdultABSTRACT
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.
Subject(s)
Activities of Daily Living , Geriatric Assessment/methods , Muscle Strength/physiology , Muscle, Skeletal/physiology , Age Factors , Aged , Aged, 80 and over , Body Height , Female , Humans , Linear Models , Male , MovementABSTRACT
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.
Subject(s)
Postural Balance/physiology , Stroboscopy/methods , Vision, Ocular/physiology , Female , Humans , Male , Young AdultABSTRACT
Anterior cruciate ligament (ACL) injury is one of the most common knee injuries among adolescent athletes. Majority of the ACL injuries occur due to pivoting, sudden deceleration, and direction change without contact with any player. Preventive interventions can reduce risks of the ACL injury, thus developing a clinician friendly biomechanical assessment tool to identify athletes with such risk factors is crucial. In this study, the authors investigated the concurrent validity of a commercially available depth sensor, Microsoft Kinect, as a cost-effective alternative to the gold-standard 3-dimensional motion analysis systems in noncontact ACL screening for adolescent athletes during side-cut maneuvers. Study participants performed 45° side-cut maneuvers while collecting data from both systems concurrently. The sagittal and frontal plane kinematics were analyzed during the full stance phase and the first 20% of the stance (early deceleration). Absolute agreement (range: ICC = .767-.989) and consistency (range: ICC = .799-.992) were excellent for all measures except early deceleration frontal plane hip angle, which displayed good absolute agreement (ICC = .643) and consistency (ICC = .625). Findings showed that the Kinect has the potential to be an effective clinical assessment tool for sagittal and frontal plane trunk, hip, and knee kinematics during the side-cut maneuvers.
Subject(s)
Anterior Cruciate Ligament Injuries/diagnosis , Movement , Adolescent , Athletes , Biomechanical Phenomena , Female , Hip Joint , Humans , Knee Joint , Male , Range of Motion, Articular , Torso , Video RecordingABSTRACT
Buskard, AN, Oh, J, Eltoukhy, M, Brounstein, SR, and Signorile, JF. A novel method to determine optimal load in elastic-based power training. J Strength Cond Res 32(9): 2401-2408, 2018-The benefits of muscular power on sport performance and older adults' abilities to live independently and resist falls is well documented. Consequently, a substantial volume of research has focused on establishing the optimal loading patterns for improving muscular power using resistance exercise; however, to date, this research has only targeted optimal loading during training with free weights or selectorized exercise machines. Conversely, no approach has been developed to establish optimal loads for elastic modalities, such as tubes and bands, commonly used for sports rehabilitation, injury prevention, and training older adults. Therefore, the purpose of this study was to evaluate a new method for determining the optimal tubes to use in power training performed with elastic resistance. Thirty-eight recreationally active college students (age, 23.7 ± 4.5 years) were recruited to perform 3 single-arm bicep curls at a maximum intended velocity using 6 elastic tubes of varying resistance. Testing was performed in a 3-dimensional (3D) motion analysis laboratory using a specially constructed platform with an integrated strain gauge to which each tube was anchored. Force data from the strain gauge and velocity data from the 3D motion capture system were then used to compute power for each tube. An analysis based on individual's cable arm curl 1-repetition maximum (1RM) was then used to generate general guidelines for the most appropriate tube to use for arm curl power training based on upper arm 1RM. Our results demonstrate the feasibility of using this methodology for other exercises, thereby establishing optimal tube use for power training based on each exercise's 1RM.
Subject(s)
Muscle Strength/physiology , Muscle, Skeletal/physiology , Resistance Training/methods , Adult , Biomechanical Phenomena , Female , Humans , Male , Motion , Recreation , Young AdultABSTRACT
PURPOSE OF REVIEW: Recent studies have attempted to identify interactions among the causes of otitis media with effusion (OME). This review discusses the interaction between allergy and infection with regard to host and environmental factors in terms of the development of OME. RECENT FINDINGS: Protection of the upper airway against microbial invasion requires active interaction between the defense mechanisms of the respiratory epithelium, including innate and adaptive immunity, and mechanical factors. The impairment of these defenses due to allergy and/or increased bacterial resistance may lead to increased susceptibility to infectious organisms in the respiratory tract and middle ear mucosa. Recent genetic studies have provided valuable information about the association of Toll-like receptor signaling variations with clinical phenotypes and the risk of infection in the middle ear. Among the causal factors of OME, allergy not only induces an inflammatory reaction in the middle ear cavity but also facilitates the invasion of infectious pathogens. There is also evidence that allergy can affect the susceptibility of patients to infection of the upper respiratory tract, including the middle ear cavity.
Subject(s)
Ear, Middle/pathology , Hypersensitivity/complications , Otitis Media with Effusion/etiology , Child , HumansABSTRACT
Cryptotia attributable to deficient posterior skin coverage frequently recurs. Because local flaps cover only the posterior aspects of the defective upper auricular cartilage and lack functional support to resist collapse of the helix, especially if severe helical cartilage anomalies are present, additional support is required to prevent the postoperative recurrence of this anomaly. The authors present cases of cryptotia treated using local flaps including a Z-plasty or formation of a trefoil flap with an additional cartilage wedge graft on the cephaloauricular sulcus to enhance projection of the helix. The combination of a graft with a local flap using a large Z-plasty or trefoil flap efficiently corrects the cryptotia, and is associated with minimal visible scarring and few complications, including recurrence.
Subject(s)
Ear Cartilage/abnormalities , Ear, External/abnormalities , Plastic Surgery Procedures/methods , Surgical Flaps/surgery , Adolescent , Adult , Cartilage/transplantation , Child , Child, Preschool , Ear Cartilage/surgery , Ear, External/surgery , Follow-Up Studies , Humans , Male , Postoperative Complications/prevention & control , Recurrence , Skin Transplantation/methods , Treatment Outcome , Young AdultABSTRACT
Verrucous carcinoma is a highly differentiated variant of squamous cell carcinoma with a high local recurrence rate. Few studies of primary verrucous carcinoma of the auricle have reported on the surgical outcome. The authors present herein a case in which a verrucous carcinoma of the auricle was successfully removed and reconstructed using a retroauricular pull-through island flap, and the authors briefly review the relevant literature.
Subject(s)
Carcinoma, Verrucous/surgery , Dermatologic Surgical Procedures , Ear Auricle/surgery , Ear Neoplasms/surgery , Aged , Ear Cartilage/surgery , Follow-Up Studies , Graft Survival , Humans , Male , Surgical Flaps/surgery , Treatment OutcomeABSTRACT
PURPOSE: The dizziness handicap inventory (DHI) is widely used to evaluate self-perceived handicap due to dizziness, and is known to correlate with vestibular function tests in chronic dizziness. However, whether DHI reflects subjective symptoms during the acute phase has not been studied. This study aims to investigate the correlations of subjective and objective measurements to highlight parameters that reflect the severity of dizziness during the first week of acute unilateral vestibulopathy. MATERIALS AND METHODS: Thirty-seven patients with acute unilateral vestibulopathy were examined. Patients' subjective perceptions of dizziness were measured using the DHI, Vertigo Visual Analog Scale (VVAS), Disability Scale (DS), and Activity-Specific Balance Scale (ABC). Additionally, the oculomotor tests, Romberg and sharpened Romberg tests, functional reach test, and dynamic visual acuity tests were performed. The correlation between the DHI and other tests was evaluated. RESULTS: DHI-total scores exhibited a moderately positive correlation with VVAS and DS, and a moderately negative correlation with ABC. However, DHI-total score did not correlate with results of the Romberg, sharpened Romberg, or functional reach tests. When compared among four groups divided according to DHI scores, VVAS and DS scores exhibited statistically significant differences, but no significant differences were detected for other test results. CONCLUSION: Our findings revealed that the DHI correlated significantly with self-perceived symptoms measured by VVAS and DS, but not ABC. There was no significant correlation with other balance function tests during the first week of acute vestibulopathy. The results suggest that DHI, VVAS and DS may be more useful to measure the severity of acute dizziness symptoms.
Subject(s)
Disability Evaluation , Dizziness/physiopathology , Postural Balance/physiology , Vestibular Neuronitis/physiopathology , Female , Humans , Male , Middle Aged , Prospective Studies , Severity of Illness Index , Vestibular Function Tests , Visual Analog ScaleABSTRACT
Transcutaneous spinal stimulation (TSS) is a promising rehabilitative intervention to restore motor function and coordination for individuals with spinal cord injury (SCI). The effects of TSS are most commonly assessed by evaluating muscle response to stimulation using surface electromyography (sEMG). Given the increasing use of robotic devices to deliver therapy and the emerging potential of hybrid rehabilitation interventions that combine neuromodulation with robotic devices, there is an opportunity to leverage the on-board sensors of the robots to measure kinematic and torque changes of joints in the presence of stimulation. This paper explores the potential for robotic assessment of the effects of TSS delivered to the cervical spinal cord. We used a four degree-of-freedom exoskeleton to measure the torque response of upper limb (UL) joints during stimulation, while simultaneously recording sEMG. We analyzed joint torque and electromyography data generated during TSS delivered over individual sites of the cervical spinal cord in neurologically intact participants. We show that site-specific effects of TSS are manifested not only by modulation of the amplitude of spinally evoked motor potentials in UL muscles, but also by changes in torque generated by individual UL joints. We observed preferential resultant action of proximal muscles and joints with stimulation at the rostral site, and of proximal joints with rostral-lateral stimulation. Robotic assessment can be used to measure the effects of TSS, and could be integrated into complex control algorithms that govern the behavior of hybrid neuromodulation-robotic systems.
Subject(s)
Electromyography , Exoskeleton Device , Robotics , Spinal Cord Injuries , Torque , Upper Extremity , Humans , Robotics/instrumentation , Male , Adult , Spinal Cord Injuries/rehabilitation , Female , Biomechanical Phenomena , Muscle, Skeletal/physiology , Cervical Cord , Healthy Volunteers , Spinal Cord Stimulation/instrumentation , Spinal Cord Stimulation/methods , Young Adult , Transcutaneous Electric Nerve Stimulation/instrumentation , Transcutaneous Electric Nerve Stimulation/methods , Cervical Vertebrae , AlgorithmsABSTRACT
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.
Subject(s)
Deafness , Hearing Aids , Speech Perception , Tinnitus , Adult , Humans , Prospective Studies , Bone Conduction , Hearing , Deafness/surgery , Treatment OutcomeABSTRACT
Necrotizing sialometaplasia of the parotid gland is infrequent and can be mistaken as a malignant disease. Its etiology is thought to be an insufficient blood supply. Bilateral involvement of this disease in parotid glands has been rarely reported in the English literature. We report a case of necrotizing sialometaplasia diagnosed after superficial parotidectomy due to bilateral parotid masses in a 69-year old heavy smoking female.
Subject(s)
Parotid Diseases/diagnosis , Sialometaplasia, Necrotizing/diagnosis , Aged , Female , Humans , Parotid Diseases/diagnostic imaging , Parotid Diseases/etiology , Parotid Diseases/surgery , Parotid Gland/diagnostic imaging , Parotid Gland/pathology , Parotid Gland/surgery , Sialometaplasia, Necrotizing/diagnostic imaging , Sialometaplasia, Necrotizing/etiology , Sialometaplasia, Necrotizing/surgery , Smoking/adverse effects , Tomography, X-Ray ComputedABSTRACT
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.
ABSTRACT
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 (ageâ¯=â¯19.1⯱â¯1.5â¯years, heightâ¯=â¯166.9⯱â¯6.7â¯cm, massâ¯=â¯62.8⯱â¯6.9â¯kg, median total concussionâ¯=â¯1.0 [interquartile rangeâ¯=â¯1.0, 2.0]), and 28 female college athletes without concussion history (ageâ¯=â¯19.1⯱â¯1.0â¯years, heightâ¯=â¯172.7⯱â¯8.3â¯cm, massâ¯=â¯65.4⯱â¯8.4â¯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-rangeâ¯=â¯0.318 to 0.999, partial correlation rangeâ¯=â¯-0.149 to 0.072). Reaction time did not differ between groups during any functional (p-rangeâ¯=â¯0.057 to 0.920) or computerized (p-rangeâ¯=â¯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.
Subject(s)
Athletic Injuries , Brain Concussion , Humans , Female , Adolescent , Young Adult , Adult , Reaction Time , Cross-Sectional Studies , Athletes , Neuropsychological TestsABSTRACT
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.
ABSTRACT
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.
Subject(s)
Spinal Cord Injuries , Spinal Cord Stimulation , Humans , Muscle, Skeletal/physiology , Evoked Potentials, Motor/physiology , Spinal Cord Injuries/complications , Quadriplegia , Thoracic VertebraeABSTRACT
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.