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1.
J Biomech Eng ; 145(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35900855

RESUMO

The anterior cruciate ligament plays a major role in maintaining the stability of the knee joint and is susceptible to injury under strenuous activity. Anterior cruciate ligament (ACL) injuries can lead to joint instability and complications such as osteoarthritis. Despite this, there is a lack of material models capable of predicting damage at a localized fiber level, hindering our ability to understand how damage develops in real-time. This work develops a continuum-damage material model of the ACL and applies the model to a finite element simulation of the knee undergoing high quadriceps tendon loading. Using quadriceps tendon loadings of 1000, 1500, and 2000 N, the development of microstructural damage within the ACL tissue was examined, and the effects of localized damage on the joint kinematics were investigated. Damage tended to develop in the midsubstance of the ACL in the present model in the anterior medial bundle region and could induce significant changes in the joint kinematics. Using this model, new insights into the development of ACL injury mechanisms can be investigated.


Assuntos
Lesões do Ligamento Cruzado Anterior , Traumatismos do Joelho , Ligamento Cruzado Anterior , Fenômenos Biomecânicos , Humanos , Joelho , Articulação do Joelho
2.
Artigo em Inglês | MEDLINE | ID: mdl-36067232

RESUMO

Distal femoral focal deficiency is an extremely rare type of congenital femoral deficiency that comprises hypoplasia of the distal femur, with a normally developed hip. We represent a unique case of distal femoral hypoplasia and deficiency of knee extensors, childhood follow-up and final treatment with exarticulation, and a comparison with previous literature.


Assuntos
Fêmur , Deformidades Congênitas das Extremidades Inferiores , Criança , Artéria Femoral , Fêmur/cirurgia , Humanos , Joelho , Articulação do Joelho
3.
J Orthop Surg Res ; 17(1): 415, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104803

RESUMO

BACKGROUND: The efficacy and safety profile of mesenchymal stem cells (MSCs) augmentation in chondral procedures are controversial. This systematic review updated the current evidence on MSCs augmentation for chondral procedures in patients with symptomatic chondral defects of the knee. METHODS: This study followed the PRISMA guidelines. The literature search was updated in August 2022. Two independent authors accessed PubMed, Google scholar, Embase, and Scopus. No additional filters or time constrains were used for the search. A cross reference of the bibliographies was also performed. All the clinical studies investigating surgical procedures for chondral defects of the knee augmented with MSCs were accessed. Defects of both tibiofemoral and patellofemoral joints were included. The following patient reported outcomes measures (PROMs) were retrieved at baseline and last follow-up: Visual Analogic Scale (VAS), Tegner Activity Scale, Lysholm Knee Scoring System, International Knee Documentation Committee (IKDC). Return to daily activities and data on hypertrophy, failure, revision surgery were also collected. Failures were defined as the recurrence of symptoms attributable to the index procedure. Revisions were defined as any reoperation at the site of the index procedure. RESULTS: A total of 15 clinical studies (411 procedures) were included. Patients returned to their prior sport activity at 2.8 ± 0.4 months. All the PROMs improved at last follow-up: Tegner (P = 0.0002), Lysholm (P < 0.0001), the IKDC (P < 0.0001), VAS (P < 0.0001). At a mean of 30.1 ± 13.9 months, 3.1% (2 of 65 patients) reported graft hypertrophy, 3.2% (2 of 63) were considered failures. No surgical revision procedures were reported. Given the lack of available quantitative data for inclusion, a formal comparison of surgical procedures was not conducted. CONCLUSION: MSCs augmentation in selected chondral procedures could be effective, with a low rate of complications. Further investigations are required to overcome the current limitations to allow the clinical translation of MSCs in regenerative medicine.


Assuntos
Doenças das Cartilagens , Células-Tronco Mesenquimais , Doenças das Cartilagens/cirurgia , Humanos , Hipertrofia , Joelho , Articulação do Joelho/cirurgia
4.
PLoS One ; 17(9): e0274789, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36112602

RESUMO

BACKGROUND: Genu varus (GV) is a common deformity characterized by leg bending, which seriously threatens human health. At present, there is no definite conclusion to explain the cause of genu varus. The purpose of this study is to systematically review and meta-analysis the effectiveness and scientific basis of the clinical efficacy of customized orthopedic insoles on genu varus and hope to provide a reference for future research in this field. METHODS: The following electronic databases will be searched from inception to January 2022: Pubmed, Cochrane Library, MEDLINE, EMBASE, Web of Science, Weipu, Wanfang Data, and CNKI. Randomized controlled trials (RCTs) were collected to examine the effect of lateral wedge-shaped orthopedic insole on patients with genu varus. We will consider inclusion, select high-quality articles for data extraction and analysis, and summarize the intervention effect of lateral wedge orthotic insoles on patients with genu varus. Two reviewers will screen titles, abstracts, and full texts independently according to inclusion criteria; Data extraction and risk of bias assessment were performed in the included studies. We will use a hierarchy of recommended assessment, development, and assessment methods to assess the overall certainty of the evidence and report findings accordingly. Endnote X8 will be applied in selecting the study, Review Manager 5.3 will be applied in analyzing and synthesizing. RESULTS: The results will provide evidence for judging the effect of lateral wedge-shaped orthopedic insole on patients with genu varus. CONCLUSION: Our study will provide reliable evidence for the effect of lateral wedge-shaped orthopedic insole on patients with genu varus. TRAIL REGISTRATION: INPLASY registration number: INPLASY202190002 https://www.google.com/search?client=firefox-b-d&q=INPLASY202190002.


Assuntos
Genu Varum , Humanos , Joelho , Metanálise como Assunto , Sapatos , Revisões Sistemáticas como Assunto
5.
J Am Podiatr Med Assoc ; 112(2)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-36115036

RESUMO

Ganglion cysts are relatively common entities, but intraneural ganglia within peripheral nerves are rare and poorly understood. We present a case of a 51-year-old man who presented with acute left dropfoot. Initial magnetic resonance imaging (MRI) was misinterpreted as common peroneal neuritis consistent with a traction injury corroborated by the patient's history. However, after surgical decompression and external neurolysis were performed, the patient's symptoms worsened. Repeated MRI revealed an intraneural ganglion cyst of the common peroneal nerve with connection to the superior tibiofibular joint by means of its anterior recurrent branch that was evident retrospectively on preoperative MRI. It is crucial to carefully inspect atypical cases to further recognize and appreciate the dynamic aspect of this disease or "roller-coaster" phenomenon. Intraneural ganglion cysts rely heavily on intraneural and extraneural pressure gradients for propagation, which can be drawn from the expanded work of the unifying articular theory. This report emphasizes the importance of understanding the pathoanatomical and hydraulic factors to appropriately identify and treat intraneural ganglion cysts. Increased recognition of this pathologic entity as a differential diagnosis for acute onset dropfoot is also highlighted.


Assuntos
Cistos Glanglionares , Neuropatias Fibulares , Cistos Glanglionares/diagnóstico , Cistos Glanglionares/diagnóstico por imagem , Humanos , Joelho , Masculino , Pessoa de Meia-Idade , Nervo Fibular/patologia , Nervo Fibular/cirurgia , Neuropatias Fibulares/diagnóstico , Neuropatias Fibulares/etiologia , Neuropatias Fibulares/cirurgia , Estudos Retrospectivos
6.
Medicine (Baltimore) ; 101(37): e30631, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36123932

RESUMO

Exercise therapy has been reported as an effective treatment method for patellofemoral pain syndrome (PFPS). However, there is a lack of studies regarding the effectiveness of balance exercise in the treatment of patients with PFPS. This study aimed to prospectively compare changes in proprioception, neuromuscular control, knee muscle strength, and patient-reported outcomes between patients with PFPS treated with knee alignment-oriented static balance exercise (SBE) and dynamic balance exercise (DBE). The participants were divided into 2 groups: 17 knee alignment-oriented SBE group and 19 knee alignment-oriented DBE group. Proprioception was assessed by dynamic postural stability using postural stabilometry. Neuromuscular control and knee muscle strength were measured for acceleration time and peak torque in quadriceps muscle using an isokinetic device. Patient-reported outcomes were evaluated using a visual analog scale for pain and the Kujala Anterior Knee Pain Scale. There was greater improvement in dynamic postural stability (0.9 ±â€…0.3 vs 1.2 ±â€…0.5; 95% confidence interval [CI]: 0, 0.6; Effect size: 0.72; P = .021) and quadriceps AT (40.5 ±â€…14.3 vs 54.1 ±â€…16.9; 95% CI: 2.9, 24.2; Effect size: 0.86; P = .014) in the DBE group compared to the SBE group. Knee alignment-oriented DBE can be more effective in improving dynamic postural stability and quadriceps muscle reaction time compared with the knee alignment-oriented SBE in PFPS patients with dynamic knee valgus.


Assuntos
Síndrome da Dor Patelofemoral , Terapia por Exercício , Humanos , Joelho , Dor , Síndrome da Dor Patelofemoral/terapia , Estudos Prospectivos
7.
J Musculoskelet Neuronal Interact ; 22(3): 326-335, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36046988

RESUMO

OBJECTIVES: This study aimed to examine the efficacy of isometric knee extension and flexion peak torque and rate of torque development (RTD) variables to distinguish starters from non-starters in collegiate female soccer players. METHODS: Eleven starters (20±2 years) and 13 non-starters (19±1 years) performed three isometric maximal voluntary contractions of the knee extensors and flexors. Peak torque, peak RTD, and RTD at 0-100 (RTD100) and 0-200 (RTD200) ms were obtained from each contraction. RESULTS: The starters produced significantly greater (P=0.002-0.015) knee extension and flexion peak RTD, RTD100, and RTD200 values than the non-starters. There were no significant differences (P>0.050) between the starters and non-starters for peak torque. Discriminant analysis revealed thresholds of 9.36, 7.98, and 6.97 Nm⋅s-1⋅kg-1 for knee extension RTD200 and knee flexion peak RTD and RTD100, respectively. These thresholds showed 81.8% sensitivity and 76.9 to 92.3% specificity for identifying playing group membership. CONCLUSIONS: Our findings indicate that RTD may be a better parameter than peak torque at differentiating between playing level in collegiate female soccer players. The discriminant analysis thresholds for the RTD variables demonstrated good sensitivity and specificity, and therefore, may be used as indices to identify players with a high degree of soccer playing ability.


Assuntos
Futebol , Feminino , Humanos , Contração Isométrica , Joelho , Articulação do Joelho , Extremidade Inferior , Força Muscular , Músculo Esquelético , Torque
8.
J Musculoskelet Neuronal Interact ; 22(3): 369-374, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36046993

RESUMO

OBJECTIVES: Previous studies showed that vibration foam rolling (VFR) on damaged muscles improves muscle soreness and range of motion (ROM). VFR intervention can also increase the ROM and pain pressure threshold (PPT) in the non-rolling side, known as a cross-education effect. However, this is not clear for the non-rolling side. Therefore, this study aimed to investigate the cross-education effects of VFR intervention on ROM, muscle soreness, and PPT in eccentrically damaged muscles. METHODS: Participants were sedentary healthy male volunteers (n=14, 21.4±0.7 y) who performed eccentric exercise of the knee extensors with the dominant leg and received 90-s VFR intervention of the quadriceps at the nondamaged side 48 h after the eccentric exercise. The dependent variables were measured before the exercise (baseline), before (preintervention), and after VFR intervention (postintervention) 48 h after the eccentric exercise. The Bonferroni post hoc test was used to determine the differences between baseline, preintervention, and postintervention. RESULTS: Results showed that the VFR intervention on the nondamaged side 48 h after the eccentric exercise improved significantly (p<0.05) the knee flexion ROM, muscle soreness at palpation, and PPT compared to baseline. CONCLUSION: VFR intervention on the nondamaged side can recover ROM and muscle soreness in eccentrically damaged muscles.


Assuntos
Mialgia , Vibração , Humanos , Joelho/fisiologia , Masculino , Músculo Esquelético/fisiologia , Mialgia/terapia , Músculo Quadríceps/fisiologia , Amplitude de Movimento Articular/fisiologia , Vibração/uso terapêutico
9.
Pain Res Manag ; 2022: 4323045, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36071945

RESUMO

Pain sensitization and neuropathic pain-like symptoms are some of the common pain symptoms in patients with lower limbs, including hip and knee, osteoarthritis (HOA/KOA). Exercise therapy has been the first-line treatment; however, the effects differ for each patient. This prospective cohort study investigated the relationship between the effectiveness of exercise therapy and pretreatment characteristics (radiologic severity, pain sensitization, and neuropathic pain-like symptoms) of patients with HOA/KOA. We assessed the pain intensity using a numerical rating scale (NRS) before and after 12 weeks of exercise therapy in patients with HOA/KOA (n = 101). Before treatment, the Kellgren-Lawrence (K-L) grade; minimum joint space width (mJSW); pressure pain threshold (PPT) and temporal summation of pain (TSP) at the affected joint, tibia, and forearm; Central Sensitization Inventory-9; and painDETECT questionnaire (PDQ) were assessed. Cluster analysis was based on the pretreatment NRS and change in NRS with exercise therapy to identify the subgroups of pain reduction. The pretreatment characteristics of each cluster were compared. According to the results of the cluster analyses, patients in cluster 1 had severe pain that did not improve after exercise therapy, patients in cluster 2 had severe pain that improved, and those in cluster 3 had mild pain that improved. The patients in cluster 1 exhibited lower PPT at all measurement sites, higher TSP at the affected joint, and higher PDQ scores than those in other clusters. There was no difference in the K-L grade and mJSW among the clusters. The subgroup with severe pain and pain sensitization or neuropathic pain-like symptoms at pretreatment, even with mild joint deformity, may have difficulty in achieving improvement in pain after 12 weeks of exercise therapy. These findings could be useful for prognosis prediction and for planning exercise therapy and combining with other treatment.


Assuntos
Neuralgia , Osteoartrite do Quadril , Osteoartrite do Joelho , Terapia por Exercício , Humanos , Joelho , Neuralgia/complicações , Neuralgia/terapia , Osteoartrite do Quadril/complicações , Osteoartrite do Quadril/terapia , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/terapia , Estudos Prospectivos
10.
Med Eng Phys ; 107: 103844, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36068026

RESUMO

This study aimed to assess the utility of peak counting in dynamic muscle contractions. Surface electromyography (sEMG) data were collected from three quadriceps femoris muscles of twelve healthy individuals during 50 repeated isokinetic knee extensions. The level of muscle fatigue was quantified by applying peak counting, mean frequency (MNF), and median frequency (MDF) to sEMG signals, and a fatigue index value was extracted for each parameter. The Bland-Altman plots were used to show the agreement between the methods based on the fatigue index values. The relationship between MNF, MDF and number of peaks (NoP) was described by using linear regression models. The results showed that the peak counting method measures the fatigue level of the muscles equivalent to MNF and MDF in terms of fatigue index values. The peak counting method has a stronger relationship with MNF than MDF, considering the R-squared values of the linear regression models. In conclusion, peak counting was found to be a valid method, and the NoP was evaluated as a reliable parameter in the quantitative analysis of muscle fatigue during dynamic contractions.


Assuntos
Contração Muscular , Fadiga Muscular , Eletromiografia , Humanos , Joelho , Contração Muscular/fisiologia , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Músculo Quadríceps
11.
Artigo em Inglês | MEDLINE | ID: mdl-36078475

RESUMO

Externally focused attention is known to induce superior results in the movement outcome, whereas focusing attention on the moving body (internal focus) causes conscious control and constrains action. The study investigated effects on knee trajectory and whole-body movement complexity when addressing knee alignment using externally (EF) vs. internally (IF) focused instructions. Young ski racers, n = 24 (12 male), performed landings with subsequent jumps to submaximal height. Movements were tracked and analyzed during the ground contact phase. Sets of jumps were executed without instruction (CON), followed by EF and IF instructions on knee alignment in a random order. Medial-lateral displacement of the knee in landing quantified task achievement, and whole-body principal component analysis was used to compute movement complexity. Knee alignment instructions led to a significantly lower medial knee displacement compared to CON (p = 0.001, ηp2 = 0.35). EF vs. IF did not reach significance. EF, as well as IF instructions increased the prominence of the first movement pattern (p = 0.01, ηp2 = 0.22) with a reduction of higher-order patterns (p = 0.002, W = 0.11), suggesting a strategy of freezing degrees of freedom. Both instructions addressing the movement form positively influenced knee displacement during landing, and both led to a freezing strategy, simplifying whole-body coordination.


Assuntos
Articulação do Joelho , Joelho , Fenômenos Biomecânicos , Humanos , Extremidade Inferior , Masculino , Movimento
13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 4218-4221, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36085698

RESUMO

Advances in sensor technology have provided an opportunity to measure gait characteristics using body-worn inertial measurement units (IMUs). Whilst research investigating the validity of IMUs in reporting gait characteristics is extensive, research investigating the reliability of IMUs is limited. This study aimed to investigate the inter-session reliability of wireless IMU derived measures of gait (i.e., knee angle, range of motion) taking multiple test administrators into account. Fifteen healthy volunteers (43 ± 15 years) completed two visits. Within each visit, participants were required to perform two sets of 6 gait trials (6-metre walk tests). IMUs were placed on the participant in 7 locations on the lower limbs and waist. A different test administrator (n = 3) applied the IMUs at each set. At visit 2, this procedure was repeated with the same test administrators as visit 1. Kinematic measures of maximum angle (Knee_Max), minimum angle (Knee_Min), and range of motion (RoM) are reported for the left and right knee. The intraclass correlation coefficients (ICC), standard error of measurement (SEM) and minimum detectable change (MDC) are reported to determine IMU reliability. The results confirmed moderate to good inter-session reliability across all features (0.73-0.87). SEM values ranged from 1.21-3.32° and MDC values ranged from 3.37 - 9.21°. Therefore, IMUs appear to be a reliable method to determine inter-session gait characteristics across multiple test administrators.


Assuntos
Marcha , Articulação do Joelho , Fenômenos Biomecânicos , Humanos , Joelho , Reprodutibilidade dos Testes
14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 2093-2096, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36085925

RESUMO

MRI reconstruction is the fundamental task of obtaining diagnostic quality images from MRI sensor data and is an active area of research for improving accuracy, speed and memory requirements of the process. Complex-valued neural networks have previously achieved superior MRI reconstructions compared to real-valued nets. But those works operated in the image domain to denoise poor quality reconstructions of the raw sensor (k-space) data. Also small-scale or proprietary datasets with few clinical images or raw k-space volumes were used in these works, and none of the works use publicly available large-scale raw k-space datasets. Recent studies have shown that cross-domain neural networks for MRI reconstruction, or networks which leverage information from both k-space and image domains, have better potential than single-domain networks which operate only in one domain. We study the effects of complex-valued operations on a top-performing cross-domain neural network for MRI reconstruction called the Primal-Dual net, or PD-net. The PD-net is a fully convolutional architecture that takes input as raw k-space data and outputs the reconstructions, thus performing both the inversion and denoising tasks. We experiment with the publicly available, large-scale fastMRI single-coil knee dataset having 973 train volumes and 199 validation volumes. Our proposed method (Complex PD-net) achieves PSNR and SSIM of 33.3 dB and 0.8033 respectively, compared to 32.13 dB and 0.728 obtained by PD-net. Our Complex PD-net achieves 10.3% higher SSIM with just over 50% of the total parameters w.r.t. the SOTA methodology.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Humanos , Processamento de Imagem Assistida por Computador/métodos , Joelho/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 4334-4337, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36086015

RESUMO

Transfemoral amputees who run are required to learn how to control their prosthetic leg motion to avoid falling with unintended prosthetic knee flexion because the function of the existing prosthetic knee for running is likened to a simple hinge joint during stance. However, the risk of falling and injury is a barrier to participation in sports and exercise. We have addressed this concern by developing a passive mechanism for a prosthetic knee; however, the mechanism that locks knee flexion with ground reaction forces (GRFs) could not completely avoid unintended prosthetic knee flexion. The present study aims to reconsider the function of the prosthetic knee for running and propose a new prosthetic knee mechanism. Time is an alternative way to control the lock/unlock of flexion without GRFs; therefore, the new prosthetic knee mechanism should limit flexion after a certain period from the moment that the prosthesis leaves the ground. We developed a rough prototype to confirm the function of the new prosthetic knee and conducted an evaluation experiment. The subject who was attached to the simulated thigh socket and prototype of the new prosthetic knee performed level walking. The results indicated that the new mechanism allowed flexion only during the first half of the swing phase, meaning the subject was able to walk without falling. According to the literature, swing time is approximately constant among different speeds. The new mechanism would appropriately function under actual running conditions. Clinical Relevance-This proposes a new passive prosthetic knee mechanism for above-knee amputees to run safely.


Assuntos
Amputados , Membros Artificiais , Prótese do Joelho , Humanos , Joelho , Articulação do Joelho
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 2531-2534, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36086092

RESUMO

Physiotherapy includes treatment to restore and optimize mobility after surgery, injury, disease, and/or degeneration. Based on assessments throughout the recovery process from visual observations of movement, exercises are prescribed to perform at home between clinic sessions. Although technical advances have facilitated remote communication between therapists and patients, accurate assessment of at-home exercises is challenged by a lack of direct observation. The current study advances remote assessment tools to assess key lower body exercises prescribed in a case study following recovery from arthroscopic partial meniscectomy (APM). Using Vicon motion capture, recovery metrics related to range of motion, strength, and gait function were extracted. Peak knee flexion angle on the operated leg during heel slide increased from 91.61° ± 4.17° to 127.42° ± 2.35° (p<0.05), although significant differences were found compared to the non-operated leg at Day 6 (138.19° ± 5.44°, p<0.05). Repetition times in heel slide and leg raise exercises on the affected leg decreased from Day 2 (2.74s) to Day 6 (1.07s), indicating strength recovery. Step length asymmetry decreased by 61.22% and step width asymmetry decreased by 41.75% from Day 2 to Day 6 post surgery, demonstrating improved gait function. This work presents a sample of automated recovery metrics that can be used for therapists to assess rehabilitation and inform the recovery process. Implications of the study findings on remote assessment using wearables are discussed. This work presents kinematics based quantifiable lower limb rehabilitation metrics to assess recovery objectives (e.g., knee flexion angle to assess knee range of motion) used by clinicians to inform recovery remotely.


Assuntos
Meniscectomia , Meniscos Tibiais , Fenômenos Biomecânicos , Humanos , Joelho , Articulação do Joelho/cirurgia , Meniscos Tibiais/cirurgia
17.
Cells ; 11(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36010590

RESUMO

Glycoproteins are involved in the development of many diseases, while the type and content of N-glycoproteins in the cartilage of osteoarthritis (OA) and Kashin-Beck disease (KBD) are still unclear. This research aims to identify N-glycoproteins in knee cartilage patients with OA and KBD compared with normal control (N) adults. The cartilage samples were collected from gender- and age-matched OA (n = 9), KBD (n = 9) patients, and N (n = 9) adults. Glycoproteomics and label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) obtained N-glycoproteins of KBD and OA. A total of 594 N-glycoproteins and 1146 N-glycosylation peptides were identified. The identified data were further compared and analyzed with Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Protein-Protein Interactions (PPI). Pairwise comparison of the glycoproteins detected in the three groups showed that integrin beta-1 (ITGB1), collagen alpha-1 (II) chain (COL2A1), collagen alpha-1 (VII) chain (COL7A1), carbohydrate sulfotransferase 3 (CHST-3), carbohydrate sulfotransferase 4 (CHST-4), thrombospondin 2 (THBS2), bone morphogenetic protein 8A (BMP8A), tenascin-C (TNC), lysosome-associated membrane protein (LAMP2), and beta-glucuronidase (GUSB) were significantly differentially expressed. GO results suggested N-glycoproteins mainly belonged to protein metabolic process, single-multicellular and multicellular organism process, cell adhesion, biological adhesion, and multicellular organism development. KEGG and PPI results revealed that key N-glycoproteins were closely related to pathways for OA and KBD, such as phagosome, ECM-receptor interaction, lysosome, focal adhesion, protein digestion, and absorption. These results reflected glycoprotein expression for OA and KBD in the process of ECM degradation, material transport, cell-cell or cell-ECM interaction, and information transduction. These key significantly differentially expressed N-glycoproteins and pathways lead to the degeneration and degradation of the cartilage of OA and KBD mainly by disrupting the synthesis and catabolism of basic components of ECM and chondrocytes and interfering with the transfer of material or information. The key N-glycoproteins or pathways in this research are potential targets for pathological mechanisms and therapies of OA and KBD.


Assuntos
Cartilagem Articular , Doença de Kashin-Bek , Osteoartrite , Adulto , Cartilagem Articular/metabolismo , Cromatografia Líquida , Colágeno Tipo VII/metabolismo , Glicoproteínas/metabolismo , Humanos , Doença de Kashin-Bek/genética , Doença de Kashin-Bek/metabolismo , Doença de Kashin-Bek/patologia , Joelho , Osteoartrite/metabolismo , Espectrometria de Massas em Tandem
18.
Artigo em Inglês | MEDLINE | ID: mdl-35954598

RESUMO

Patellofemoral pain syndrome (PFPS) is highly prevalent; it can cause severe pain and evolve into progressive functional loss, leading to difficulties performing daily tasks such as climbing and descending stairs and squatting. This systematic review aimed to find evidence, in the literature, of squat movements that can cause or worsen PFPS. This work was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, and its protocol was registered in PROSPERO (CRD42019128711). From the 6570 collected records, 37 were included. From these 37 articles, 27 present a causal relationship between knee flexion and PFPS, 8 describe a relationship, considering the greater existence of muscle contractions, and one article did not describe this relationship in its results. The main limitations stem from the fact that different studies used different evaluation parameters to compare the force exerted on the patellofemoral joint. Furthermore, most studies are focused on sports populations. After analysing the included works, it was concluded that all squat exercises can cause tension overload in the knee, especially with a knee flexion between 60° and 90° degrees. The main causal/worsening factors of PFPS symptoms are the knee translocation forward the toes (on the same body side) when flexing the knee, and the muscle imbalance between the thigh muscles.


Assuntos
Síndrome da Dor Patelofemoral , Terapia por Exercício , Humanos , Joelho , Articulação do Joelho , Síndrome da Dor Patelofemoral/epidemiologia , Síndrome da Dor Patelofemoral/etiologia
19.
Exp Physiol ; 107(9): 1061-1070, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35923141

RESUMO

NEW FINDINGS: What is the central question of this study? Can bilateral knee extensor force accuracy be improved following 4 weeks of unilateral force accuracy training and are there any subsequent alterations to central and/or peripheral motor unit features? What is the main finding and its importance? In the trained limb only, knee extensor force tracking accuracy improved with reduced motor unit firing rate variability in the vastus lateralis, and there was no change to neuromuscular junction transmission instability. Interventional strategies to improve force accuracy may be directed to older/clinical populations where such improvements may aid performance of daily living activities. ABSTRACT: Muscle force output during sustained submaximal isometric contractions fluctuates around an average value and is partly influenced by variation in motor unit (MU) firing rates. MU firing rate (FR) variability seemingly reduces following exercise training interventions; however, much less is known with respect to peripheral MU properties. We therefore investigated whether targeted force accuracy training could lead to improved muscle functional capacity and control, in addition to determining any alterations of individual MU features. Ten healthy participants (seven females, three males, 27 ± 6 years, 170 ± 8 cm, 69 ± 16 kg) underwent a 4-week supervised, unilateral knee extensor force accuracy training intervention. The coefficient of variation for force (FORCECoV ) and sinusoidal wave force tracking accuracy (FORCESinu ) were determined at 25% maximal voluntary contraction (MVC) pre- and post-training. Intramuscular electromyography was utilised to record individual MU potentials from the vastus lateralis (VL) muscles at 25% MVC during sustained contractions, pre- and post-training. Knee extensor muscle strength remained unchanged following training, with no improvements in unilateral leg-balance. FORCECoV and FORCESinu significantly improved in only the trained knee extensors by ∼13% (P = 0.01) and ∼30% (P < 0.0001), respectively. MU FR variability significantly reduced in the trained VL by ∼16% (n = 8; P = 0.001), with no further alterations to MU FR or neuromuscular junction transmission instability. Our results suggest muscle force control and tracking accuracy is a trainable characteristic in the knee extensors, which is likely explained by the reduction in MU FR variability which was apparent in the trained limb only.


Assuntos
Joelho , Músculo Quadríceps , Eletromiografia , Feminino , Humanos , Contração Isométrica/fisiologia , Joelho/fisiologia , Articulação do Joelho/fisiologia , Masculino , Músculo Esquelético/fisiologia , Músculo Quadríceps/fisiologia
20.
Am J Sports Med ; 50(11): 2961-2971, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35914270

RESUMO

BACKGROUND: Individuals with anterior cruciate ligament (ACL) reconstruction (ACLR) are a population that has a higher risk for ACL injury compared with the general population. To reduce the reinjury rate and improve the rehabilitation outcome after ACLR, risk factors for ACL injury have to be addressed. PURPOSE: To compare the knee biomechanics during side-cutting and isokinetic strength of the thigh muscle of the reconstructed leg with those of the contralateral leg and healthy controls and investigate the knee movement asymmetries in individuals with ACLR. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 16 participants with ACLR (ACLR group; 11.8 ± 1.1 months after reconstruction) and 16 healthy controls (control group) were recruited. Landmark coordinates and ground-reaction forces during side-cutting and isokinetic strength of hamstring and quadriceps were collected. Two-way analysis of variance with the mixed design was performed to compare each dependent variable between groups and across legs. RESULTS: The reconstructed leg had a significantly smaller knee flexion angle (P = .004) and less quadriceps strength (P = .003) than the contralateral leg. The knee extension moment and knee external rotation angle were decreased compared with both the contralateral leg (P = .001, P = .003, respectively) and the healthy control leg (P = .001, P = .001, respectively). The ACLR group showed greater knee abduction angles (P = .004) and smaller knee external rotation moments (P = .006) than the control group. The ACLR group also demonstrated greater asymmetries of knee flexion angle (P = .015), knee external rotation angle (P = .001), knee extension moment (P = .013), knee abduction moment (P = .001), and quadriceps strength (P = .046) than the control group. CONCLUSION: Knee biomechanics in the leg with ACLR were altered mainly in the sagittal plane during side-cutting compared with the contralateral leg. The altered movement patterns between the ACLR and control groups were primarily observed in the frontal and transverse planes. The ACLR group also demonstrated greater asymmetries of sagittal knee movement and concentric quadriceps strength than the control group. CLINICAL RELEVANCE: Individuals with ACLR showed different alterations in the reconstructed and contralateral leg compared with healthy controls. These results suggest that rehabilitation programs after ACLR should further focus on restoring the knee flexion angle and quadriceps strength. Injury prevention programs need to be further targeted in the altered movement patterns observed between the ACLR and the healthy groups.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/reabilitação , Fenômenos Biomecânicos , Humanos , Joelho/cirurgia , Articulação do Joelho/fisiologia , Articulação do Joelho/cirurgia , Força Muscular/fisiologia , Músculo Quadríceps/fisiologia
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