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1.
Biosensors (Basel) ; 13(1)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36671931

RESUMO

The incidence of cardiovascular diseases is continuously increasing around the world. Therefore, the study of new methods for diagnosing cardiovascular diseases is very important. Early diagnosis and evaluation of the effectiveness of treatments are among the most important tasks. In this work, we study changes in vascular compliance and vascular tone of the lower extremities in a patient diagnosed with an early stage of varicose veins. The study is based on recording the bioimpedance signals of the lower extremities and their parts using the Rheo-32 multichannel device. Registration in the monitoring system takes place in two stages: the first in a state of relaxation, and the second after applying a local massage on one of the legs for five minutes. The results indicate a change in the type of vascular tone of the lower extremities after the massage, while the type of vascular tone changes and shifts on average towards the normotonic type. The method proposed in this study makes it possible to quantitatively and qualitatively assess changes in the tone of the vessels of the extremities.


Assuntos
Doenças Cardiovasculares , Varizes , Humanos , Varizes/diagnóstico , Varizes/etiologia , Varizes/terapia , Extremidade Inferior/irrigação sanguínea , Perna (Membro)/irrigação sanguínea , Veias
2.
BMJ Open Qual ; 12(1)2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36690383

RESUMO

INTRODUCTION: Soreness is a common complaint in patients who receive lumbar spine surgery (LSS) for degenerative lumbar spine diseases (DLSD). However, soreness is not assessed independently and its impacts on outcomes of LSS remains largely unknown. Sng(pronounced sә-ng, ) in Chinese language is the word with the closest meaning to soreness, and Chinese-speaking people naturally use sng to describe their non-pain 'soreness' symptom. This study was aimed to investigate the prevalence and impacts of soreness or sng on outcome of LSS by introducing Visual Analogue Scale (VAS) of sng on back and leg. MATERIALS AND METHODS: This prospective cohort study recruited patients who receive LSS for DLSD. Participants completed the patient-reported outcome measures at 1 week before and 1 years after LSS. The patient-reported outcome measures included (1) VAS for back pain, leg pain, back sng and leg sng, (2) Oswestry Disability Index (ODI) and (3) RAND 36-item Short Form Health Survey. The minimal clinical important difference (MCID) of ODI and physical component health-related quality of life (HRQoL) was used. RESULTS: A total of 258 consecutive patients were included and 50 dropped out at follow-up. Preoperatively, the prevalence of sng was comparable to pain both on back and leg; postoperatively, the prevalence of sng was higher than pain. Leg and back sng were associated with preoperative and postoperative mental HRQoL, respectively. The reduction of sng on back and leg were significantly less than pain postoperatively. Leg sng was the only symptom independently associated with attaining MCID. CONCLUSION: Soreness or sng should be assessed independently from pain in patients receiving LSS for DLSD because soreness or sng had substantial clinical impacts on the outcome of LSS.


Assuntos
Dor nas Costas , Qualidade de Vida , Humanos , Estudos Prospectivos , Dor nas Costas/etiologia , Medição da Dor , Perna (Membro)
3.
Tidsskr Nor Laegeforen ; 142(1)2023 Jan 17.
Artigo em Inglês, Norueguês | MEDLINE | ID: mdl-36655972

RESUMO

Neuropathy can have many causes, some less well known than others. In this article, we present the case of a young man with progressive neurological deficit over several months. The cause was found to be an increasing social problem.


Assuntos
Hipestesia , Perna (Membro) , Masculino , Humanos , Hipestesia/etiologia
5.
Radiology ; 306(2): e212607, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36689345

RESUMO

HISTORY: A 49-year-old man presented with right foot drop, bilateral cruralgia mainly on the left side, and genital and perianal hypoesthesia, which started suddenly 12 days before. After onset of symptoms, the patient also experienced an accidental fall at home, resulting in a left fibular fracture, which was treated with reduction and with seven-hole plate Synthes Locking Compression Plate at the orthopedic clinic. The neurologic examination showed paresthesias on the posterior aspect of both thighs and crural regions that was worse on the left side, hypoesthesia in the L5 root region on the right side, and right foot drop. There was no urinary retention or fecal incontinence. The patient denied past surgery, back trauma, heavy manual labor, hypermobility, or any other remarkable medical history. The patient was afebrile. Laboratory results on the 1st day of hospitalization showed increased C-reactive protein level (0.62 mg/dL; reference range, 0.0-0.5 mg/dL), elevated erythrocyte sedimentation rate (60 mm/h; reference range, 0-20 mm/h), and increased aspartate transaminase (38 U/L [0.63 µkat/L]; reference range, 0-31 U/L [0-0.52 µkat/L]), alanine transaminase (70 U/L [1.17 µkat/L]; reference range, 0-31 U/L [0-0.52 µkat/L]), and high lymphocyte (4.55 × 103/mL; reference range, [1.0-3.0] ×103/mL), and neutrophil (8.79 × 103/mL; reference range, [2.0-7.0] × 103/mL) levels. Absence of coagulopathy was demonstrated by normal coagulation values (international normalized ratio, 1.19; reference value, 0.80-1.25; activated partial thromboplastin time ratio, 0.88 second; reference range, 0.79-1.27 seconds). Electroneurography showed marked hypoevocable F response in the right tibia. Electromyography indicated severe reduction of muscle recruitment pertaining to right L4, L5, and S1 nerve territory and, to a lesser extent, of muscles pertaining to L3 territory bilaterally in the absence of spontaneous denervation. Unenhanced CT and contrast-enhanced MRI of the lumbosacral spine were performed.


Assuntos
Deslocamento do Disco Intervertebral , Neuropatias Fibulares , Masculino , Humanos , Pessoa de Meia-Idade , Hipestesia , Imageamento por Ressonância Magnética , Perna (Membro) , Vértebras Lombares
6.
Clin J Sport Med ; 33(1): 61-66, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36599361

RESUMO

OBJECTIVE: To identify the incidence and characteristics associated with a higher injury risk in recreational runners who suffered a running-related injury (RRI) in the previous 12 months. DESIGN: Prospective cohort study among recreational runners who registered for a Dutch running event (5-42.2 km) and suffered an RRI in the 12 months before inclusion. SETTING: Open population. PARTICIPANTS: Recreational runners with a previous reported injury. ASSESSMENT OF RISK FACTORS: At baseline, information on demographics, training characteristics, health complaints, and RRI history was collected. MAIN OUTCOME MEASURES: With 3 follow-up questionnaires (2 weeks before, 1 day after, and 1 month after the running event), the occurrence of new RRIs was registered. RESULTS: In total, 548 participants (55.1%) sustained a new RRI during follow-up. In total, 20.5% of the new RRIs was located at the same anatomical location as the previous RRI. Runners who registered for a marathon had a higher chance to sustain a new RRI [odd ratio (OR) 1.72; 95% confidence intervals (CIs), 1.17-2.53]. Also previous RRIs in the upper leg (OR 1.59; 95% CI, 1.15-2.19) and lower leg (OR 1.61; 95% CI, 1.18-2.21) were associated with an increased injury risk. CONCLUSIONS: Especially being a marathon runner and the anatomical location of previous RRIs seem to be associated with the injury risk in recreational runners with a previous RRI.


Assuntos
Traumatismos em Atletas , Humanos , Estudos Prospectivos , Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/etiologia , Extremidade Inferior , Perna (Membro) , Inquéritos e Questionários , Fatores de Risco
7.
Sci Rep ; 13(1): 131, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36599887

RESUMO

Inertial Measurement Units (IMUs) are a potential way to monitor the mobility of people outside clinical or laboratory settings at an acceptable cost. To increase accuracy, multiple IMUs can be used. By embedding multiple sensors into everyday clothing, it is possible to simplify having to put on individual sensors, ensuring sensors are correctly located and oriented. This research demonstrates how clothing-mounted IMU readings can be used to identify 4 common postures: standing, sitting, lying down and sitting on the floor. Data were collected from 5 healthy adults, with each providing 1-4 days of data with approximately 5 h each day. Each day, participants performed a fixed set of activities that were video-recorded to provide a ground truth. This is an analysis of accelerometry data from 3 sensors incorporated into right trouser-leg at the waist, thigh and ankle. Data were classified as static/ dynamic activities using a K-nearest neighbour (KNN) algorithm. For static activities, the inclination angles of the three sensors were estimated and used to train a second KNN classifier. For this highly-selected dataset (60000-70000 data points/posture), the static postures were classified with 100% accuracy, illustrating the potential for clothing-mounted sensors to be used in posture classification.


Assuntos
Postura , Dispositivos Eletrônicos Vestíveis , Adulto , Humanos , Perna (Membro) , Coxa da Perna , Vestuário
9.
J Coll Physicians Surg Pak ; 33(1): 103-106, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36597244

RESUMO

OBJECTIVE: To determine the causes of interventions in patients with acute limb ischemia (ALI), the time lapse of presentation, and the outcome. STUDY DESIGN: An observational study. METHODOLOGY: All delayed acute limb ischemia cases (presenting later than 6 hours after the onset of symptoms) were included in the study. Cases of ALI secondary to accidental trauma were excluded except those of iatrogenic trauma like patients with intravenous drug abuse and intra-arterial accidental drug infiltration. Patients' demographic data, clinical history, aetiology, examination findings, and treatment data; including type of surgery, level of amputation, adjunctive treatment were recorded. RESULTS: Total number of delayed ALI cases was 147. Mean age was 59.52 ±17.77 years. Seventy-five (51%) were females while 72(49%) were males. The right lower limb was involved in 56(38%) cases. A hundred (68%) thromboembolectomies were successful and limbs were saved, while 19(12.9%) had failure after the procedure. Three (2%) patients expired within 24 hours of thromboembolectomy. Twenty-five (17%) had frank gangrene at presentation and ended up in amputations while 122 (82.9%) had questionable viability and underwent limb salvage procedures. CONCLUSION: Delayed presentation of ALI is very common; timely management with effective thromboembolectomies can save limbs in most of the patients. KEY WORDS: Acute limb ischemia (ALI), Treatment, Amputation, Thromboembolectomy, embolism.


Assuntos
Arteriopatias Oclusivas , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Fatores de Risco , Resultado do Tratamento , Arteriopatias Oclusivas/complicações , Isquemia/diagnóstico , Isquemia/etiologia , Isquemia/cirurgia , Perna (Membro) , Salvamento de Membro/efeitos adversos , Estudos Retrospectivos , Doença Aguda
10.
Artigo em Chinês | MEDLINE | ID: mdl-36597369

RESUMO

Objective:To analyze the clinical effect of free posterior lateral peroneal artery perforator flap of lower leg in repairing postoperative defect of oropharyngeal carcinoma. Methods:Thirty-six patients with oropharyngeal carcinoma admitted to the Department of Oral and Maxillofacial Surgery, the First Affiliated Hospital of Bengbu Medical College from June 2016 to June 2019 were analyzed and followed up, eighteen patients were treated with free posterior lateral peroneal artery perforator flap of the lower leg to repair the postoperative defects(experimental group), and eighteen patients were treated with free forearm flap(control group). The survival rate of the transplanted flap, the wound stageⅠhealing rate and average hospitalization time were compared between the two groups. Kaplan-Meier method was used to calculate the 1-year and 3-year survival rates of patients after operation, and log-rank test was used to compare the difference between the survival curves of the two groups; The recovery of swallowing and palatopharyngeal closure function of patients in the two groups at 3, 6, 12 and 18 months after operation was calculated and statistically analyzed through the water swallow test and the air blowing method. Results:There was one case of skin flap necrosis in both the experimental group and the control group, and the survival rate was 94.4%. The wound stageⅠhealing rate in the surgical area was 94.4% in both groups. The wound healing rates of the donor area in the experimental group and the control group were 100.0% and 94.4% respectively. The average hospitalization time of the experimental group and the control group was 16.9 days and 17.2 days, respectively, with no significant difference (P>0.05). The overall survival rates of all patients at 1-year and 3-year were 91.2% and 66.5% respectively; The 1-year and 3-year survival rates of the experimental group and the control group were 94.1%, 69.3% and 88.2%, 63.7%, respectively, and there was no significant difference between the two groups (P>0.05). The 1-year and 3-year survival rates of P16+ and P16 - patients were 100.0%, 80.0% and 85.7%, 64.3%, respectively, and there was no significant difference between the two groups (P>0.05). There was no significant difference in the evaluation of swallowing and velopharyngeal closure function between the two groups at 3 and 6 months after operation (P>0.05), but there was a significant difference at 12 and 18 months after operation (P<0.05). Conclusion:The anatomic position of the perforating vessels of the free posterior lateral peroneal artery perforator flap of the lower leg is constant, and it can be prepared into single leaf, multi leaf, chimeric and other flaps according to the tissue defect space. And the concealed supply area can be directly drawn to suture. At the same time, the skin flap has strong plasticity. Therefore, the skin flap can be used as a common skin flap to repair the defects after the operation of oropharyngeal carcinoma.


Assuntos
Carcinoma , Neoplasias Orofaríngeas , Retalho Perfurante , Lesões dos Tecidos Moles , Humanos , Transplante de Pele/métodos , Perna (Membro)/cirurgia , Retalho Perfurante/cirurgia , Retalho Perfurante/transplante , Neoplasias Orofaríngeas/cirurgia , Artérias/cirurgia , Carcinoma/cirurgia , Lesões dos Tecidos Moles/cirurgia , Resultado do Tratamento
11.
Neuromodulation ; 26(1): 172-181, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36608962

RESUMO

INTRODUCTION: A novel, spinal cord stimulation (SCS) system with a battery-free miniaturized implantable pulse generator (IPG) was used in this feasibility study. The system uses an external power source that communicates bidirectionally with the IPG (< 1.5 cm3). Human factors, subject comfort, and effects on low back and leg pain were evaluated in this first-in-human study. MATERIALS AND METHODS: A prospective, multicenter, open-label clinical trial was initiated to evaluate the safety and performance of a novel miniaturized stimulator in the treatment of chronic, intractable leg and low-back pain. Eligible subjects were recruited for the study and gave consent. Subjects who passed the screening/trial phase (defined as ≥ 50% decrease in pain) continued to the long-term implant phase and were followed up at predefined time points after device activation. Interim clinical and usability outcomes were captured and reported at 90 days. RESULTS: Results of 22 subjects who chose a novel pulsed stimulation pattern therapy using the battery-free IPG (< 1.5 cm3) are described here. At 90-days follow-up, the average pain reduction was 79% in the leg (n = 22; p < 0.0001) and 76% in the low back (n = 21; p < 0.0001) compared with baseline. Responder rates (≥ 50% pain relief) at 90 days were 86% in leg pain (19/22) and 81% in low-back pain (17/21). Subjects rated the level of comfort of the external wearable power source to be 0.41 ± 0.73 at 90 days on an 11-point rating scale (0 = very comfortable, 10 = very uncomfortable). DISCUSSION: These interim results from the ongoing study indicate the favorable efficacy and usability of a novel, externally powered, battery-free SCS IPG (< 1.5 cm3) for leg and low-back pain. Study subjects wore the external power source continuously and found it comfortable, and the system provided significant pain relief. These preliminary findings warrant further investigation. CLINICAL TRIAL REGISTRATION: The Clinicaltrials.gov registration number for the study is ACTRN12618001862235.


Assuntos
Dor Crônica , Dor Lombar , Dor Intratável , Estimulação da Medula Espinal , Humanos , Perna (Membro) , Estudos Prospectivos , Estimulação da Medula Espinal/métodos , Medição da Dor/métodos , Dor Crônica/terapia , Dor Lombar/terapia , Resultado do Tratamento , Medula Espinal
12.
PLoS One ; 18(1): e0280361, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36649257

RESUMO

The validity and reliability of the Lafayette stability platform are well-established for double leg testing. However, no evaluation of single leg (SL) stance on the platform was discovered yet. Therefore, this study aimed to investigate the reliability of conducting the SL stance on the Lafayette platform. Thirty-six healthy and active university students (age 23.2 ± 3.2 years; BMI 21.1 ± 3.1 kg/m2) were tested twice, one week apart (week 1; W1, week 2; W2). They stood on their dominant leg with eyes-open (EO) and eyes-closed (EC) in random order. Three successful trials of 20 seconds each were recorded. The duration during which the platform was maintained within 0° of tilt was referred to as time in balance (TIB). At all-time points, TIB was consistently longer in EO (EOW1: 17.02 ± 1.04s; EOW2: 17.32 ± 1.03s) compared to EC (ECW1: 11.55 ± 1.73s; ECW2: 13.08 ± 1.82s). A ±10 seconds difference was demonstrated in the Bland-Altman analysis in both EO and EC. Lower standard error of measurement (SEM) and coefficient of variation (CV) indicated consistent output. High intraclass correlation coefficient (ICC) values were seen between weeks (EO = 0.74; EC = 0.76) and within weeks (EOW1 = 0.79; EOW2 = 0.86; ECW1 = 0.71; ECW2 = 0.71). Although statistical measures (i.e., SEM, CV, and ICC) indicated good reliability of Lafayette for SL tasks, the wide agreement interval is yet to be clinically meaningful. Factors underlying the wide variation need to be identified before Lafayette is used for TIB assessment.


Assuntos
Perna (Membro) , Equilíbrio Postural , Humanos , Adulto Jovem , Adulto , Reprodutibilidade dos Testes , Olho , Modalidades de Fisioterapia
13.
Artigo em Inglês | MEDLINE | ID: mdl-36673671

RESUMO

A novel and fun exercise robot (LOCOBOT) was developed to improve balance ability. This system can control a spherical robot on a floor by changing the center of pressure (COP) based on weight-shifting on a board. The present study evaluated leg muscle activity and joint motion during LOCOBOT exercise and compared the muscle activity with walking and sit-to-stand movement. This study included 10 healthy male adults (age: 23.0 ± 0.9 years) and examined basic LOCOBOT exercises (front-back, left-right, 8-turn, and bowling). Electromyography during each exercise recorded 13 right leg muscle activities. Muscle activity was represented as the percentage maximal voluntary isometric contraction (%MVIC). Additionally, the joint motion was simultaneously measured using an optical motion capture system. The mean %MVIC differed among LOCOBOT exercises, especially in ankle joint muscles. The ankle joint was primarily used for robot control. The mean %MVIC of the 8-turn exercise was equivalent to that of walking in the tibialis anterior, and the ankle plantar flexors were significantly higher than those in the sit-to-stand motion. Participants control the robot by ankle strategy. This robot exercise can efficiently train the ankle joint muscles, which would improve ankle joint stability.


Assuntos
Perna (Membro) , Robótica , Adulto , Humanos , Masculino , Adulto Jovem , Perna (Membro)/fisiologia , Músculo Esquelético/fisiologia , Tornozelo/fisiologia , Eletromiografia , Equilíbrio Postural/fisiologia
14.
Neuromodulation ; 26(1): 182-191, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36503999

RESUMO

OBJECTIVES: The aim of this article is to discuss the possible mechanisms of action (MOAs) and results of a pilot study of a novel, anatomically placed, and paresthesia-independent, neurostimulation waveform for the management of chronic intractable pain. MATERIALS AND METHODS: A novel, multilayered pulsed stimulation pattern (PSP) that comprises three temporal layers, a Pulse Pattern layer, Train layer, and Dosage layer, was developed for the treatment of chronic intractable pain. During preliminary development, the utility was evaluated of anatomical PSP (aPSP) in human subjects with chronic intractable pain of the leg(s) and/or low back, compared with that of traditional spinal cord stimulation (T-SCS) and physiological PSP. The scientific theory and testing presented in this article provide the preliminary justification for the potential MOAs by which PSP may operate. RESULTS: During the pilot study, aPSP (n = 31) yielded a greater decrease in both back and leg pain than did T-SCS (back: -60% vs -46%; legs: -63% vs -43%). In addition, aPSP yielded higher responder rates for both back and leg pain than did T-SCS (61% vs 48% and 78% vs 50%, respectively). DISCUSSION: The novel, multilayered approach of PSP may provide multimechanistic therapeutic relief through preferential fiber activation in the dorsal column, optimization of the neural onset response, and use of both the medial and lateral pathway through the thalamic nuclei. The results of the pilot study presented here suggest a robust responder rate, with several subjects (five subjects with back pain and three subjects with leg pain) achieving complete relief from PSP during the acute follow-up period. These clinical findings suggest PSP may provide a multimechanistic, anatomical, and clinically effective management for intractable chronic pain. Because of the limited sample size of clinical data, further testing and long-term clinical assessments are warranted to confirm these preliminary findings.


Assuntos
Dor Crônica , Dor Intratável , Estimulação da Medula Espinal , Humanos , Perna (Membro) , Estimulação da Medula Espinal/métodos , Projetos Piloto , Dor nas Costas/terapia , Dor Crônica/terapia , Resultado do Tratamento , Medula Espinal
15.
J Appl Physiol (1985) ; 134(1): 190-202, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36476161

RESUMO

This study evaluates neuromechanical control and muscle-tendon interaction during energy storage and dissipation tasks in hypergravity. During parabolic flights, while 17 subjects performed drop jumps (DJs) and drop landings (DLs), electromyography (EMG) of the lower limb muscles was combined with in vivo fascicle dynamics of the gastrocnemius medialis, two-dimensional (2D) kinematics, and kinetics to measure and analyze changes in energy management. Comparisons were made between movement modalities executed in hypergravity (1.8 G) and gravity on ground (1 G). In 1.8 G, ankle dorsiflexion, knee joint flexion, and vertical center of mass (COM) displacement are lower in DJs than in DLs; within each movement modality, joint flexion amplitudes and COM displacement demonstrate higher values in 1.8 G than in 1 G. Concomitantly, negative peak ankle joint power, vertical ground reaction forces, and leg stiffness are similar between both movement modalities (1.8 G). In DJs, EMG activity in 1.8 G is lower during the COM deceleration phase than in 1 G, thus impairing quasi-isometric fascicle behavior. In DLs, EMG activity before and during the COM deceleration phase is higher, and fascicles are stretched less in 1.8 G than in 1 G. Compared with the situation in 1 G, highly task-specific neuromuscular activity is diminished in 1.8 G, resulting in fascicle lengthening in both movement modalities. Specifically, in DJs, a high magnitude of neuromuscular activity is impaired, resulting in altered energy storage. In contrast, in DLs, linear stiffening of the system due to higher neuromuscular activity combined with lower fascicle stretch enhances the buffering function of the tendon, and thus the capacity to safely dissipate energy.NEW & NOTEWORTHY For the first time, the neuromechanics of distinct movement modalities that fundamentally differ in their energy management function have been investigated during overload systematically induced by hypergravity. Parabolic flight provides a unique experimental setting that allows near-natural movement execution without the confounding effects typically associated with load variation. Our findings show that gravity-adjusted muscle activities are inversely affected within jumps and landings. Specifically, in 1.8 G, typical task-specific differences in neuromuscular activity are reduced during the center of mass deceleration phase, resulting in fascicle lengthening, which is associated with energy dissipation.


Assuntos
Músculo Esquelético , Tendões , Humanos , Fenômenos Biomecânicos , Tendões/fisiologia , Músculo Esquelético/fisiologia , Eletromiografia , Perna (Membro)/fisiologia , Contração Muscular/fisiologia
16.
Exp Brain Res ; 241(1): 249-261, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36481937

RESUMO

In humans, peripheral sensory stimulation inhibits subsequent motor evoked potentials (MEPs) induced by transcranial magnetic stimulation; this process is referred to as short- or long-latency afferent inhibition (SAI or LAI, respectively), depending on the inter-stimulus interval (ISI) length. Although upper limb SAI and LAI have been well studied, lower limb SAI and LAI remain under-investigated. Here, we examined the time course of the soleus (SOL) muscle MEP following electrical tibial nerve (TN) stimulation at the popliteal fossa at ISIs of 20-220 ms. When the conditioning stimulus intensity was three-fold the perceptual threshold, MEP amplitudes were inhibited at an ISI of 220 ms, but not at shorter ISIs. TN stimulation just below the Hoffman (H)-reflex threshold intensity inhibited MEP amplitudes at ISIs of 30, 35, 100, 180 and 200 ms. However, the relationship between MEP inhibition and the P30 latency of somatosensory evoked potentials (SEPs) did not show corresponding ISIs at the SEP P30 latency that maximizes MEP inhibition. To clarify whether the site of afferent-induced MEP inhibition occurs at the cortical or spinal level, we examined the time course of SOL H-reflex following TN stimulation. H-reflex amplitudes were not significantly inhibited at ISIs where MEP inhibition occurred but at an ISI of 120 ms. Our findings indicate that stronger peripheral sensory stimulation is required for lower limb than for upper limb SAI and LAI and that lower limb SAI and LAI are of cortical origin. Moreover, the direct pathway from the periphery to the primary motor cortex may contribute to lower limb SAI.


Assuntos
Córtex Motor , Humanos , Córtex Motor/fisiologia , Perna (Membro) , Reflexo H , Vias Aferentes/fisiologia , Tempo de Reação/fisiologia , Inibição Neural/fisiologia , Nervo Mediano/fisiologia , Estimulação Elétrica , Potencial Evocado Motor/fisiologia , Estimulação Magnética Transcraniana
17.
Exp Brain Res ; 241(1): 277-288, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36484793

RESUMO

Age- and sex-related alterations in the control of multiple muscles during contractions are not well understood. The purpose of the present study was to examine the age and sex differences in force steadiness and intermuscular coherence (IMC), and thereby to clarify the functional role of IMC during plantar flexion. Twenty-six young (YNG, 23-34 years), thirty middle-aged (MID, 35-64 years) and twenty-four older adults (OLD, 65-82 years) performed submaximal isometric contractions of plantar flexion, while electromyography was recorded from the soleus (SOL), gastrocnemius lateralis/medialis (GL/GM) and tibialis anterior (TA) muscles. Coefficient of variation (CV) of torque and IMC in the alpha, beta and gamma bands was calculated. We found that OLD demonstrated significantly higher torque CV than YNG and MID, and males demonstrated significantly higher torque CV than females (both p < 0.05). The IMC in the gamma band (five out of the six pairs) was significantly higher in YNG than MID and/or OLD (p < 0.05), while the gamma band IMC between GL and SOL was significantly higher in females. However, age or sex differences were not detected in the alpha or beta band. Moreover, the gamma band IMC between SOL and TA had a weak (r = - 0.229) but significant (p < 0.05) negative correlation with torque CV. These results suggest that force steadiness differs with age and sex, and that the higher gamma band IMC may contribute to more stable force control during plantar flexion.


Assuntos
Perna (Membro) , Caracteres Sexuais , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Idoso , Perna (Membro)/fisiologia , Músculo Esquelético/fisiologia , Eletromiografia/métodos , Contração Isométrica/fisiologia , Torque
18.
J Am Acad Orthop Surg ; 31(2): 106-113, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36580052

RESUMO

INTRODUCTION: Two intraoperative radiographic techniques to determine leg length and offset during anterior total hip arthroplasty (THA) are the AP pelvis and overlay techniques. The AP pelvis method measures LLDs and offset using AP fluoroscopic images, whereas the overlay method uses printed images of the native and replaced hips. The purpose of this study was to compare these techniques regarding clinical and radiographic LLD and offset discrepancies. METHODS: Patients of a single surgeon at two hospitals from September 2017 to January 2021 were retrospectively reviewed. Clinically detectable LLD was recorded. Radiographic measurements were obtained from preoperative and postoperative radiographs. LLD was determined based on the vertical distance between the lesser trochanters and the ischial tuberosities. Total offset was measured using a combination of femoral and medial offset. The Student t-test, Fisher exact test, and Wilcoxon rank sum tests were used for statistical analysis. RESULTS: Seventy-one procedures were done using the overlay technique and 61 used for the AP pelvis technique. No significant differences were observed in mean postoperative LLD (2.66 versus 2.88 mm, P = 0.66) and mean postoperative offset discrepancy (5.37 versus 4.21 mm, P = 0.143) between the overlay versus AP pelvis groups. The mean preoperative to postoperative absolute difference in offset was less than 5 mm in both groups. Clinically detectable LLD was noted in six of 71 patients in the overlay group and one of 61 in the AP pelvis group (P = 0.123). CONCLUSION: No notable differences were observed in intraoperative leg length and offset discrepancies during direct anterior THA between the AP pelvis and overlay techniques, suggesting they are equally effective in determining LLD and offset intraoperatively. The choice of technique to use anterior THA should be based primarily on the surgeon's preference, comfort, and available resources.


Assuntos
Artroplastia de Quadril , Humanos , Artroplastia de Quadril/métodos , Estudos Retrospectivos , Perna (Membro) , Pelve/diagnóstico por imagem , Pelve/cirurgia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/cirurgia , Desigualdade de Membros Inferiores/diagnóstico por imagem , Desigualdade de Membros Inferiores/etiologia , Desigualdade de Membros Inferiores/cirurgia
20.
J Neurophysiol ; 129(1): 272-284, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36475977

RESUMO

It has been shown that when humans lean in various directions, the central nervous system (CNS) recruits different motoneuron pools for task completion; common units that are active during different leaning directions, and unique units that are active in only one leaning direction. We used high-density surface electromyography (HD-sEMG) to examine if motor unit (MU) firing behavior was dependent on leaning direction, muscle (medial and lateral gastrocnemius; soleus), limits of stability, or whether a MU is considered common or unique. Fourteen healthy participants stood on a force platform and maintained their center of pressure in five different leaning directions. HD-sEMG recordings were decomposed into MU action potentials and the average firing rate (AFR), coefficient of variation (CoVISI), and firing intermittency were calculated on the MU spike trains. During the 30°-90° leaning directions both unique units and common units had higher firing rates (F = 31.31, P < 0.0001). However, the unique units achieved higher firing rates compared with the common units (mean estimate difference = 3.48 Hz, P < 0.0001). The CoVISI increased across directions for the unique units but not for the common units (F = 23.65, P < 0.0001). Finally, intermittent activation of MUs was dependent on the leaning direction (F = 11.15, P < 0.0001), with less intermittent activity occurring during diagonal and forward-leaning directions. These results provide evidence that the CNS can preferentially control separate motoneuron pools within the ankle plantarflexors during voluntary leaning tasks for the maintenance of standing balance.NEW & NOTEWORTHY In this study, we demonstrate that the different subpopulations of motor units within the three muscles comprising the ankle plantarflexors behave differently during multidirectional leaning. Our results suggest that the central nervous system has the capability to control distinct subpopulations of motor units to meet the force requirements necessary for leaning. This may allow for a precise, efficient, and flexible control strategy for the maintenance of standing balance.


Assuntos
Contração Muscular , Músculo Esquelético , Humanos , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Neurônios Motores/fisiologia , Perna (Membro) , Eletromiografia
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