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1.
Somatosens Mot Res ; 40(1): 39-45, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36538392

RESUMEN

PURPOSE: Although Kinesio Taping has been extensively used, evidence about the effect of Kinesio Taping is still insufficient. The aim is to determine the effect of Kinesio Taping on elbow joint torque and muscle activity in time and frequency domains. MATERIALS AND METHODS: Thirty-eight healthy subjects were (27 females and 11 males) randomly divided into control and Kinesio Taping groups. Kinesio Taping was applied over biceps brachii muscle in Kinesio Taping group, whereas no taping was applied to control group. Maximum elbow joint torque and electromyography activity in time and frequency domains were assessed during maximum isometric contraction of biceps brachii muscle at baseline, after 10 min, 30 min, and 24 h. Repeated measure ANOVA and mixed ANOVA tests were used for in-group and between-group comparisons, respectively. RESULTS: Elbow joint torques among four assessment sessions were statistically altered in Kinesio Taping group and greater in Kinesio Taping group than in control group (F(3,57)= 3.317, p = 0.026, ηp2 = 0.149; F(3,108)=3.325, p = 0.022, ηp2 = 0.085; respectively). No difference was found in time domain muscle activity among assessment sessions in each group and comparison of groups (p > 0.05). Low-gamma band activity was changed among assessment sessions in Kinesio Taping group (F(3,57)= 6.946, p < 0.001, ηp2 = 0.268) while group × time interaction was not determined. CONCLUSIONS: Kinesio Taping may influence joint torque of elbow more than without Kinesio Taping condition in 24th hour but the interpretation of this effect as a muscle strength enhancement compared with baseline can be arguable. Even if Kinesio Taping could not affect muscle activity in time domain, low-gamma band activity which is closely related to somatosensorial input may reach highest magnitude 24 h after Kinesio Taping.


Asunto(s)
Fuerza Muscular , Músculo Esquelético , Masculino , Femenino , Humanos , Torque , Músculo Esquelético/fisiología , Electromiografía , Contracción Isométrica
2.
J Biomech Eng ; 142(5)2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-31825073

RESUMEN

Various methods are available for simulating the movement patterns of musculoskeletal systems and determining individual muscle forces, but the results obtained from these methods have not been rigorously validated against experiment. The aim of this study was to compare model predictions of muscle force derived for a cat hindlimb during locomotion against direct measurements of muscle force obtained in vivo. The cat hindlimb was represented as a 5-segment, 13-degrees-of-freedom (DOF), articulated linkage actuated by 25 Hill-type muscle-tendon units (MTUs). Individual muscle forces were determined by combining gait data with two widely used computational methods-static optimization and computed muscle control (CMC)-available in opensim, an open-source musculoskeletal modeling and simulation environment. The forces developed by the soleus, medial gastrocnemius (MG), and tibialis anterior muscles during free locomotion were measured using buckle transducers attached to the tendons. Muscle electromyographic activity and MTU length changes were also measured and compared against the corresponding data predicted by the model. Model-predicted muscle forces, activation levels, and MTU length changes were consistent with the corresponding quantities obtained from experiment. The calculated values of muscle force obtained from static optimization agreed more closely with experiment than those derived from CMC.


Asunto(s)
Miembro Posterior , Locomoción , Animales , Gatos , Contracción Muscular , Músculo Esquelético , Tendones
3.
Curr Sports Med Rep ; 18(6): 210-216, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31385836

RESUMEN

Musculoskeletal simulation and dynamic modeling programs have been used to gain insight into lower-limb musculoskeletal injury mechanisms. In addition to the temporospatial, kinematic, and kinetic data obtained from motion analysis systems, musculoskeletal simulation programs also can provide information on joint contact and muscle forces, musculotendinous lengths and velocities, and muscle activation levels. Musculoskeletal simulation platforms may help in the assessment of risk factors for sports-related injuries. Using musculoskeletal simulations for injury prevention programs may help lower the incidence of sports injuries, and may allow for fast recovery from injury. In this review, injury mechanisms and risk factors of some of the most common lower-limb musculoskeletal injuries, including anterior cruciate ligament, patellofemoral, and hamstring injuries were summarized from a biomechanical perspective. Also, the efficacy of musculoskeletal modeling and dynamic simulation tools in helping our understanding of these injury mechanisms was discussed.


Asunto(s)
Traumatismos en Atletas/etiología , Traumatismos de la Pierna/etiología , Modelos Biológicos , Sistema Musculoesquelético/lesiones , Lesiones del Ligamento Cruzado Anterior/etiología , Fenómenos Biomecánicos , Músculos Isquiosurales/lesiones , Humanos , Articulación Patelofemoral/lesiones
4.
Jt Dis Relat Surg ; 35(2): 368-376, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38727117

RESUMEN

OBJECTIVES: The study aimed to examine the histopathological and biomechanical effects of papaverine administered intraperitoneally and locally on Achilles tendon healing in a rat model. MATERIALS AND METHODS: Forty-eight adult male Sprague-Dawley rats (range, 300 to 400 g) were used in this study conducted between October and November 2022. The rats were divided into three groups, with each group further subdivided into two for sacrifice on either the 15th (early period) or 30th (late period) day after surgery. The first (control) group received no treatment following Achilles tendon repair, while papaverine was intraperitoneally administered every other day for 10 days in the second group and locally in the third group after surgery. On the 15th and 30th days, the rats were sacrificed, and their Achilles tendons were subjected to biomechanical testing and histopathological evaluation. RESULTS: Histopathologically, there were no significant differences among the groups on the 15th day. However, on the 30th day, the locally applied papaverine group exhibited superior histopathological outcomes compared to the control group (p<0.05). Concerning the highest tensile strength values before rupture, the biomechanical assessment showed that the group receiving local papaverine treatment in the early period and both the group with systemic papaverine treatment and the one with local papaverine treatment in the late period displayed a statistically significant advantage compared to the control group (p<0.05). CONCLUSION: Locally administered papaverine has positive biomechanical effects in the early period and exhibits a positive correlation both histopathologically and biomechanically in the late period. Novel therapeutic options may be provided for patients through these findings.


Asunto(s)
Tendón Calcáneo , Papaverina , Ratas Sprague-Dawley , Traumatismos de los Tendones , Cicatrización de Heridas , Animales , Tendón Calcáneo/lesiones , Tendón Calcáneo/efectos de los fármacos , Tendón Calcáneo/patología , Tendón Calcáneo/cirugía , Papaverina/farmacología , Papaverina/administración & dosificación , Papaverina/uso terapéutico , Masculino , Adherencias Tisulares/tratamiento farmacológico , Adherencias Tisulares/patología , Cicatrización de Heridas/efectos de los fármacos , Traumatismos de los Tendones/tratamiento farmacológico , Traumatismos de los Tendones/patología , Traumatismos de los Tendones/cirugía , Ratas , Resistencia a la Tracción/efectos de los fármacos , Inyecciones Intraperitoneales , Fenómenos Biomecánicos/efectos de los fármacos , Modelos Animales de Enfermedad
5.
J Biomech ; 155: 111668, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37276682

RESUMEN

Joint moments during gait provide valuable information for clinical decision-making in patients with cerebral palsy (CP). Joint moments are calculated based on ground reaction forces (GRF) using inverse dynamics models. Obtaining GRF from patients with CP is challenging. Typically developed (TD) individuals' joint moments were predicted from joint angles using machine learning, but no such study has been conducted on patients with CP. Accordingly, we aimed to predict the dorsi-plantar flexion, knee flexion-extension, hip flexion-extension, and hip adduction-abduction moments based on the trunk, pelvis, hip, knee, and ankle kinematics during gait in patients with CP and TD individuals using one-dimensional convolutional neural networks (CNN). The anonymized retrospective gait data of 329 TD (26 years ± 14, mass: 70 kg ± 15, height: 167 cm ± 89) and 917 CP (17 years ± 9, mass:47 kg ± 19, height:153 cm ± 36) individuals were evaluated and after applying inclusion-exclusion criteria, 132 TD and 622 CP patients with spastic diplegia were selected. We trained specific CNN models and evaluated their performance using isolated test subject groups based on normalized root mean square error (nRMSE) and Pearson correlation coefficient (PCC). Joint moments were predicted with nRMSE between 18.02% and 13.58% for the CP and between 12.55% and 8.58% for the TD groups, whereas with PCC between 0.85 and 0.93 for the CP and between 0.94 and 0.98 for the TD groups. Machine learning-based joint moment prediction from kinematics could replace conventional moment calculation in CP patients in the future, but the current level of prediction errors restricts its use for clinical decision-making today.


Asunto(s)
Parálisis Cerebral , Humanos , Fenómenos Biomecánicos , Estudios Retrospectivos , Marcha , Articulación de la Rodilla
6.
Appl Bionics Biomech ; 2021: 5593037, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34257704

RESUMEN

Finite element (FE) models have frequently been used to analyze spine biomechanics. Material parameters assigned to FE spine models are generally uncertain, and their effect on the characterization of the spinal components is not clear. In this study, we aimed to analyze the effect of model parameters on the range of motion, stress, and strain responses of a FE cervical spine model. To do so, we created a computed tomography-based FE model that consisted of C2-C3 vertebrae, intervertebral disc, facet joints, and ligaments. A total of 32 FE analyses were carried out for two different elastic modulus equations and four different bone layer numbers under four different loading conditions. We evaluated the effects of elastic modulus equations and layer number on the biomechanical behavior of the FE spine model by taking the range of angular motion, stress, and strain responses into account. We found that the angular motions of the one- and two-layer models had a greater variation than those in the models with four and eight layers. The angular motions obtained for the four- and eight-layer models were almost the same, indicating that the use of a four-layer model would be sufficient to achieve a stress value converging to a certain level as the number of layers increases. We also observed that the equation proposed by Gupta and Dan (2004) agreed well with the experimental angular motion data. The outcomes of this study are expected to contribute to the determination of the model parameters used in FE spine models.

7.
Life (Basel) ; 11(9)2021 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-34575092

RESUMEN

BACKGROUND: Patellar tendon advancement (PTA) is performed for the treatment of crouch gait in patients with cerebral palsy (CP). In this study, we aimed to determine the influence of PTA in the context of single-event multilevel surgery (SEMLS) on knee joint moment and muscle forces through musculoskeletal modeling; Methods: Gait data of children with CP and crouch gait were retrospectively analyzed. Patients were included if they had a SEMLS with a PTA (PTA group, n = 18) and a SEMLS without a PTA (NoPTA group, n = 18). A musculoskeletal model was used to calculate the pre- and postoperative knee joint moments and muscle forces; Results: Knee extensor moment increased in the PTA group postoperatively (p = 0.016), but there was no statistically significant change in the NoPTA group (p > 0.05). The quadriceps muscle forces increased for the PTA group (p = 0.034), while there was no difference in the NoPTA group (p > 0.05). The hamstring muscle forces increased in the PTA group (p = 0.039), while there was no difference in the NoPTA group (p > 0.05); Conclusions: PTA was found to be an effective surgery for the treatment of crouch gait. It contributes to improving knee extensor moment, decreasing knee flexor moment, and enhancing the quadriceps and hamstring muscle forces postoperatively.

8.
Knee ; 32: 46-55, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34411886

RESUMEN

BACKGROUND: Patellar height is a valuable measure to evaluate the effect of patellar tendon advancement (PTA) on knee function. In the literature, there is no validated procedure to measure the patellar height. In this study we aimed to (1) determine the patella position through musculoskeletal modeling, (2) investigate the effects of two surgical procedures applied for PTA, and (3) assess the effect of PTA in combination with single-event multilevel surgery (SEMLS) on the knee kinematics of patients with cerebral palsy (CP) and crouch gait. METHOD: Three-dimensional gait and X-ray data of children with CP and crouch gait were retrospectively analyzed if they had received a SEMLS in combination with PTA (PTA group, n = 18) or without PTA (NoPTA group, n = 18). A computational musculoskeletal model was used to quantify patella position, knee extension moment arm, and knee kinematics pre- and postoperatively. RESULTS: Patellar height significantly decreased in the PTA group (P = 0.004), while there was no difference in the NoPTA group (P > 0.05). The bony procedure for PTA provided a better Insall-Salvati ratio than the soft tissue procedure. The peak knee extension moment arm significantly increased in the PTA group (P = 0.008). In terms of postoperative knee joint kinematics, the PTA group was closer to typically developed children than the NoPTA group. CONCLUSION: Musculoskeletal modeling was found to be an effective tool for the determination of the patellar height. PTA improved the patella position, knee extension moment arm, and knee kinematics and was an effective procedure for the surgical management of crouch gait in patients with CP.


Asunto(s)
Parálisis Cerebral , Trastornos Neurológicos de la Marcha , Ligamento Rotuliano , Fenómenos Biomecánicos , Parálisis Cerebral/complicaciones , Parálisis Cerebral/cirugía , Niño , Marcha , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Rótula/diagnóstico por imagen , Rótula/cirugía , Ligamento Rotuliano/diagnóstico por imagen , Ligamento Rotuliano/cirugía , Estudios Retrospectivos
9.
Proc Inst Mech Eng H ; 234(10): 1139-1150, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32686574

RESUMEN

Applying four anterior implants placed vertically or tilted in the mandible is considered to provide clinically reasonable results in the treatment of mandibular posterior edentulism. It is also reported that a combination of four anterior and two short posterior implants can be an alternative approach for the rehabilitation of severe atrophy cases. In this study, we aimed to evaluate the biomechanical responses of three different implant placement configurations, which represent the clinical options for the treatment of mandibular edentulism. Three-dimensional models of the mandible, prosthetic bar, dental implant, abutment, and screw were created. Finite element models of the three implant configurations (Protocol 1: Four anterior implants, Protocol 2: Four anterior and two short posterior implants, Protocol 3: Two anterior and two tilted posterior implants: All-on-4™ concept) were generated for 10 patients and analyzed under different loading conditions including chewing, biting, and impact forces. Protocol 2 led to the lowest stress concentrations over the mandible among the three protocols (p < 0.016). Protocol 2 resulted in significantly lower stresses than Protocol 3 and Protocol 1 over prosthetic bars under chewing forces (p < 0.016). None of the implant placement protocols consistently exhibited the lowest stress distribution over abutments. The lowest stresses over dental implants under the chewing, biting, and impact forces were obtained in Protocol 1, Protocol 2, and Protocol 3, respectively (p < 0.016). Protocol 3 was the best option to obtain the lowest stress values over the screws under all types of loading conditions (p < 0.016). In conclusion, Protocol 2 was biomechanically more ideal than Protocol 1 and Protocol 3 to manage the posterior edentulism.


Asunto(s)
Implantes Dentales , Mandíbula , Tornillos Óseos , Diseño de Prótesis Dental , Análisis del Estrés Dental , Análisis de Elementos Finitos , Humanos , Mandíbula/cirugía
10.
Acta Ortop Bras ; 28(5): 247-250, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33144841

RESUMEN

OBJECTIVE: We aimed to investigate the change in bone mineral density (BMD) in the first postoperative year in patients that underwent total knee arthroplasty (TKA) due to primary osteoarthritis of the knee. METHODS: Preoperative and first postoperative year dual-energy X-ray absorptiometry measurements of 76 patients with knee osteoarthritis, who undergone surgery between 2016 and 2018 due to the recommendation for TKA, were statistically evaluated in the study. RESULTS: Of the 19 patients with a normal BMD in the preoperative period, 73.7% (n = 14) continued to have a normal BMD in the postoperative period. Of the 34 patients with a low BMD (osteopenia) in the preoperative period, 91.2% (n = 31) did not show any change, whereas osteoporosis was observed in two patients (5.9%) in the postoperative period. Of the 23 patients with osteoporosis in the preoperative period, 95.7% (n = 22) did not show any change, whereas osteopenia was observed in one patient (4.3%) in the postoperative period. Both the T and Z scores of the spine (L1-L4) and proximal femur showed a slightly positive trend, however, with an insignificant statistical difference (p ≥ 0.05). CONCLUSION: Patients that underwent TKA experienced a statistically insignificant bone gain at the spine and proximal femur twelve months after the surgery. Level of Evidence III, Therapeutic Studies Investigating the Results of Treatment.


OBJETIVO: O objetivo foi investigar a alteração na densidade mineral óssea (DMO) no primeiro ano pós-operatório em pacientes submetidos à Artroplastia Total do Joelho (ATJ) por osteoartrite primária do joelho. MÉTODOS: As medidas de absortiometria radiográfica com dupla energia no pré-operatório e no primeiro ano pós-operatório de 76 pacientes com osteoartrite do joelho, operados entre 2016 e 2018 devido à indicação de ATJ, foram avaliadas estatisticamente no estudo. RESULTADOS: Dos 19 pacientes com DMO normal no pré-operatório, 73.7% (n = 14) continuaram com DMO normal no pós-operatório. Dos 34 pacientes com baixa DMO (osteopenia) no pré-operatório, 91.2% (n = 31) não apresentaram alteração, enquanto osteoporose foi observada em dois pacientes (5.9%) no pós-operatório. Dos 23 pacientes com osteoporose no pré-operatório, 95.7% (n = 22) não apresentaram alteração, enquanto osteopenia foi observada em um paciente (4.3%) no pós-operatório. Os escores T e Z da coluna vertebral (L1-L4) e do fêmur proximal mostraram uma tendência levemente positiva, mas a diferença foi estatisticamente insignificante (p ≥ 0.05). CONCLUSÃO: Os pacientes submetidos à ATJ apresentaram um ganho ósseo estatisticamente insignificante na coluna vertebral e no fêmur proximal doze meses após a cirurgia. Nível de Evidência III, Estudos Terapêuticos - Investigação dos resultados do tratamento.

11.
Eur Spine J ; 18(7): 972-7, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19301045

RESUMEN

The purpose of this study was to develop a quantitative skin impedance test that could be used to diagnose spinal cord injury (SCI) if any, especially in unconscious and/or non-cooperative SCI patients. To achieve this goal, initially skin impedance of the sensory key points of the dermatomes (between C3 and S1 bilaterally) was measured in 15 traumatic SCI patients (13 paraplegics and 2 tetraplegics) and 15 control subjects. In order to classify impedance values and to observe whether there would be a significant difference between patient and subject impedances, an artificial neural network (ANN) with back-propagation algorithm was employed. Validation results of the ANN showed promising performance. It could classify traumatic SCI patients with a success rate of 73%. By assessing the experimental protocols and the validation results, the proposed method seemed to be a simple, objective, quantitative, non-invasive and non-expensive way of assessing SCI in such patients.


Asunto(s)
Impedancia Eléctrica , Electrodiagnóstico/métodos , Respuesta Galvánica de la Piel/fisiología , Traumatismos de la Médula Espinal/diagnóstico , Traumatismos de la Médula Espinal/fisiopatología , Médula Espinal/fisiopatología , Adolescente , Adulto , Algoritmos , Inteligencia Artificial , Electrónica Médica/instrumentación , Electrónica Médica/métodos , Humanos , Persona de Mediana Edad , Redes Neurales de la Computación , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador/instrumentación , Piel/inervación , Piel/fisiopatología , Fenómenos Fisiológicos de la Piel , Médula Espinal/patología , Adulto Joven
12.
Int J Occup Saf Ergon ; 25(4): 530-544, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29252111

RESUMEN

In this study, responses of biodynamic human body models to whole-body vibration during a vehicle ride were investigated. Accelerations were acquired from three different body parts, such as the head, upper torso and lower torso, of 10 seated passengers during a car ride while two different road conditions were considered. The same multipurpose vehicle was used during all experiments. Additionally, by two widely used biodynamic models in the literature, a set of simulations were run to obtain theoretical accelerations of the models and were compared with those obtained experimentally. To sustain a quantified comparison between experimental and theoretical approaches, the root mean square acceleration and acceleration spectral density were calculated. Time and frequency responses of the models demonstrated that neither of the models showed the best prediction performance of the human body behaviour in all cases, indicating that further models are required for better prediction of the human body responses.


Asunto(s)
Aceleración , Vibración , Adulto , Automóviles , Fenómenos Biomecánicos , Humanos , Masculino , Modelos Biológicos , Postura
13.
Hum Mov Sci ; 66: 310-317, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31136904

RESUMEN

We aimed to determine the force irradiation effect of kinesiotaping (KT) on contralateral muscle activity during unilateral muscle contraction. Forty healthy (26 females, 14 males) subjects were divided into two groups: KT and control groups. KT was applied on the biceps brachii at the contralateral limb (non-dominant limb) in the KT group, whereas no taping was applied to the control group. All participants performed unilateral isometric, concentric, and eccentric contractions with their dominant upper limbs (exercised limb) by means of an isokinetic dynamometer, while the contralateral limb was in the resting condition, neutral position, and motionless during the testing procedure. During the exercise, contralateral biceps brachii muscle activity was recorded by surface electromyography (EMG). To quantify the muscle activation, EMG signals were expressed as a percentage of the maximal isometric voluntary contraction, which is referred to as %EMGmax. The KT group showed significantly higher %EMGmax in the biceps brachii compared to the control group at the contralateral limb during the isometric, concentric, and eccentric contractions (p = 0.035, p = 0.046, and p = 0.002, respectively) The median values of the contralateral muscle activity were 2.74 %EMGmax and 6.62 %EMGmax during the isometric contraction for the control and KT groups, respectively (p = 0.035). During the concentric contraction, the median values of the contralateral muscle activity were 1.61 %EMGmax and 9.39 %EMGmax for the control and KT groups, respectively (p = 0.046). The median values of the contralateral muscle activity were 4.49 %EMGmax and 22.89 %EMGmax for the eccentric contraction for the control and KT groups, respectively (p = 0.002). In conclusion, KT application on the contralateral limb increased the contralateral muscle activation in the biceps brachii during the unilateral isometric, concentric, and eccentric contractions.

14.
Appl Bionics Biomech ; 2019: 8203597, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30944583

RESUMEN

In this study, we aimed to quantitatively monitor and describe the gait functions of patients, who underwent iliac crest bone grafting in atrophic jaw augmentation operation, by taking into account the alterations of gait parameters and muscle forces in the early recovery course. To do so, temporospatial and kinematic gait parameters of ten patients during pre- and postoperative periods were recorded, and forces of the gluteus medius, gluteus maximus, and iliacus muscles were calculated. Three postoperative periods were specified as one week (post-op1), two weeks (post-op2), and three weeks (post-op3) after the surgery. Restoring process of the gait patterns was comparatively evaluated by analyzing the gait parameters and muscle forces for pre- and postoperative periods. Temporospatial and kinematic parameters of post-op3 were closer to those obtained in pre-op than those in post-op1 and post-op2 (p < 0.05). Muscle forces calculated in post-op3 showed the best agreement with those in pre-op among the postoperative periods in terms of both magnitude and correlation (p < 0.05). In conclusion, the patients began to regain their preoperative gait characteristics from the second week after surgery, but complete recovery in gait was observed three weeks after the surgery.

15.
Acta Ortop Bras ; 26(2): 82-85, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29983622

RESUMEN

OBJECTIVE: To assess the histopathologic and biomechanical effects of hyaluronic acid (HA) and high-dose vitamin C (VC) on rat Achilles tendon healing. METHODS: Forty-eight Sprague-Dawley rats were randomized to HA and VC and control groups with equal numbers. Each group was further divided into two subgroups to be sacrificed on Day 15 (n=8) and Day 30 (n=8). The Achilles tendons were cut and repaired. While the control rats remained untreated, HA and VC were administered after repair. The repaired tendons were removed for biomechanical and histopathologic analyses. In the biomechanical tests, the tendons were stretched to failure and maximum forces were measured. For histopathologic examination, the specimens were interpreted semiquantitatively using Movin's grading scale and Bonar scores. RESULTS: The highest mean forces were obtained in the HA group on Day 15 and in the VC group on Day 30, with a significant difference between HA and VC on Day 15 between control and VC on Day 30 (p<0.05). Histological examination showed both Movin and Bonar scores decreased in all groups on Day 30, with significant improvements in the HA and VC groups (p<0.05). CONCLUSION: Our results demonstrated that both VC and HA had therapeutic effects on tendon healing, especially in the late phase. Level of Evidence I; High quality randomized trial with statistically significant difference.


OBJETIVO: Avaliar os efeitos histopatológicos e biomecânicos do ácido hialurônico (AH) e altas doses de vitamina C (VC) na cicatrização do tendão do calcâneo em ratos. MÉTODOS: Quarenta e oito ratos Sprague-Dawley foram randomizados em grupo AH, grupo VC e grupo controle, iguais em número. Cada grupo foi dividido em dois subgrupos a serem sacrificados no Dia 15 (n = 8) e no Dia 30 (n = 8). Os tendões do calcâneo foram cortados e reparados. Enquanto os ratos do grupo controle permaneceram não tratados, os do grupo AH/VC receberam AH e VC após o reparo. Os tendões reparados foram removidos para análises biomecânicas e histopatológicas. Nos testes biomecânicos, os tendões foram estirados até a falha e as forças máximas foram medidas. No exame histopatológico, as amostras foram interpretadas semiquantitativamente usando os escores de Movin e de Bonar. RESULTADOS: As forças médias mais altas foram obtidas no grupo AH no Dia 15 e no grupo VC, no Dia 30, com diferença significativa entre os grupos HA e VC no Dia 15 e entre os grupos controle e VC (p < 0,05). No exame histológico, os escores de Movin e Bonar diminuíram em todos os grupos no dia 30, com melhora significativas nos grupos AH e VC (p < 0,05). CONCLUSÕES: Nossos resultados demonstraram que tanto a VC quanto o AH tiveram efeitos terapêuticos sobre cicatrização do tendão, especialmente na fase tardia. Nível de Evidência I; Estudo clínico randomizado de alta qualidade com ou sem diferença estatisticamente significante.

16.
Eklem Hastalik Cerrahisi ; 29(1): 13-9, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29526154

RESUMEN

OBJECTIVES: This study aims to compare the histopathological and biomechanical effects of low molecular weight heparin (LMWH) and rivaroxaban, which are frequently used in orthopedic surgery for thromboembolic prophylaxis, on rat Achilles tendon healing. MATERIALS AND METHODS: In the study, 36 adult, male Sprague Dawley rats weighing between 300 g and 400 g were used. Three groups were formed including 12 rats in each. Achilles tendons of all rats were cut and repaired. Nadroparin calcium was administered subcutaneously for 21 days at a dose of 170 IU AXa to the first group (LMWH group). Rivaroxaban was administered daily at a dose of 3 mg/kg for 21 days as gastric lavage to the second group (rivaroxaban group). The third group was identified as the control group and no medication was administered in this group. At the end of three weeks, tendons extracted from the groups were examined histopathologically and biomechanically. RESULTS: Bonar's and Movin's scores obtained as a result of histopathological examination were statistically significantly higher in the control group (p=0.003 and p=0.004, respectively) (high scores indicate that tendon healing is not sufficient). When type I and type III collagen ratios were examined, type I collagen ratio, which should be found at a higher ratio in mature tendon, was statistically significantly higher in rivaroxaban and LMWH groups compared with the control group (p=0.002). As a result of biomechanical examination, higher mean maximum force values were obtained from the rivaroxaban group compared with the LMWH group (p=0.31). Mean maximum force values obtained from the control group were higher than those obtained from the LMWH group (p=0.03) and the rivaroxaban group (p=0.18). CONCLUSION: Histopathological examination revealed that both LMWH and rivaroxaban have positive effects on tendon healing. However, the same positive effects were not detected in biomechanical examination.


Asunto(s)
Tendón Calcáneo/fisiopatología , Anticoagulantes/farmacología , Inhibidores del Factor Xa/farmacología , Heparina de Bajo-Peso-Molecular/farmacología , Rivaroxabán/farmacología , Cicatrización de Heridas/efectos de los fármacos , Tendón Calcáneo/metabolismo , Tendón Calcáneo/cirugía , Animales , Fenómenos Biomecánicos/efectos de los fármacos , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Traumatismos de los Tendones/cirugía
17.
J Orthop Surg (Hong Kong) ; 26(2): 2309499018777885, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29848169

RESUMEN

PURPOSE: To investigate the biomechanical, histological, and radiological effects of sildenafil and pentoxifylline on femoral fracture healing in rats. METHODS: Forty-eight Sprague-Dawley rats were divided into three groups equally according to the pharmacological agents to be investigated. Femoral shaft fractures were formed in the left side. Group 1 (control group), group 2, and group 3 were administered with saline, sildenafil, and pentoxifylline during the fracture healing process, respectively. Eight rats from each group were euthanized on days 15 and 30. X-ray images of the rats were taken after euthanasia for radiographical examination. Femur samples were subjected to histopathological and biomechanical (three-point bending) examinations. RESULTS: Radiologically, no difference between the Goldberg scores of the groups was found for day 15 ( p > 0.05), while higher Goldberg scores were obtained from group 2 than that of group 1 ( p > 0.05) and group 3 ( p < 0.05) for day 30. In the biomechanical analysis, higher mean breaking forces were found both for day 15 and day 30 from group 2 than those obtained from group 1 (for day 15 p > 0.05 and day 30 p > 0.05) and group 3 (for day 15 p < 0.05 and day 30 p < 0.01). Higher mean absorbed energy values were obtained from group 2 than those obtained from group 1 (for day 15 p > 0.05 and day 30 p < 0.05) and group 3 (for day 15 p < 0.01 and day 30 p < 0.01). A significant difference was not found between the histological scores of all groups ( p > 0.05) for day 15, while the histological score of group 1 on day 30 was found to be significantly lower than that of sildenafil and pentoxifylline groups ( p < 0.05). CONCLUSION: Sildenafil had a positive effect on fracture healing, while pentoxifylline did not provide consistent positive effect.


Asunto(s)
Fracturas del Fémur/terapia , Curación de Fractura/efectos de los fármacos , Inhibidores de Fosfodiesterasa/uso terapéutico , Animales , Fenómenos Biomecánicos , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/patología , Masculino , Radiografía , Ratas , Ratas Sprague-Dawley
18.
Acta ortop. bras ; 28(5): 247-250, Sept.-Oct. 2020. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1130775

RESUMEN

ABSTRACT Objective: We aimed to investigate the change in bone mineral density (BMD) in the first postoperative year in patients that underwent total knee arthroplasty (TKA) due to primary osteoarthritis of the knee. Methods: Preoperative and first postoperative year dual-energy X-ray absorptiometry measurements of 76 patients with knee osteoarthritis, who undergone surgery between 2016 and 2018 due to the recommendation for TKA, were statistically evaluated in the study. Results: Of the 19 patients with a normal BMD in the preoperative period, 73.7% (n = 14) continued to have a normal BMD in the postoperative period. Of the 34 patients with a low BMD (osteopenia) in the preoperative period, 91.2% (n = 31) did not show any change, whereas osteoporosis was observed in two patients (5.9%) in the postoperative period. Of the 23 patients with osteoporosis in the preoperative period, 95.7% (n = 22) did not show any change, whereas osteopenia was observed in one patient (4.3%) in the postoperative period. Both the T and Z scores of the spine (L1-L4) and proximal femur showed a slightly positive trend, however, with an insignificant statistical difference (p ≥ 0.05). Conclusion: Patients that underwent TKA experienced a statistically insignificant bone gain at the spine and proximal femur twelve months after the surgery. Level of Evidence III, Therapeutic Studies Investigating the Results of Treatment.


RESUMO Objetivo: O objetivo foi investigar a alteração na densidade mineral óssea (DMO) no primeiro ano pós-operatório em pacientes submetidos à Artroplastia Total do Joelho (ATJ) por osteoartrite primária do joelho. Métodos: As medidas de absortiometria radiográfica com dupla energia no pré-operatório e no primeiro ano pós-operatório de 76 pacientes com osteoartrite do joelho, operados entre 2016 e 2018 devido à indicação de ATJ, foram avaliadas estatisticamente no estudo. Resultados: Dos 19 pacientes com DMO normal no pré-operatório, 73.7% (n = 14) continuaram com DMO normal no pós-operatório. Dos 34 pacientes com baixa DMO (osteopenia) no pré-operatório, 91.2% (n = 31) não apresentaram alteração, enquanto osteoporose foi observada em dois pacientes (5.9%) no pós-operatório. Dos 23 pacientes com osteoporose no pré-operatório, 95.7% (n = 22) não apresentaram alteração, enquanto osteopenia foi observada em um paciente (4.3%) no pós-operatório. Os escores T e Z da coluna vertebral (L1-L4) e do fêmur proximal mostraram uma tendência levemente positiva, mas a diferença foi estatisticamente insignificante (p ≥ 0.05). Conclusão: Os pacientes submetidos à ATJ apresentaram um ganho ósseo estatisticamente insignificante na coluna vertebral e no fêmur proximal doze meses após a cirurgia. Nível de Evidência III, Estudos Terapêuticos - Investigação dos resultados do tratamento.

19.
Acta ortop. bras ; 26(2): 82-85, Mar.-Apr. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-949721

RESUMEN

ABSTRACT Objective: To assess the histopathologic and biomechanical effects of hyaluronic acid (HA) and high-dose vitamin C (VC) on rat Achilles tendon healing. Methods: Forty-eight Sprague-Dawley rats were randomized to HA and VC and control groups with equal numbers. Each group was further divided into two subgroups to be sacrificed on Day 15 (n=8) and Day 30 (n=8). The Achilles tendons were cut and repaired. While the control rats remained untreated, HA and VC were administered after repair. The repaired tendons were removed for biomechanical and histopathologic analyses. In the biomechanical tests, the tendons were stretched to failure and maximum forces were measured. For histopathologic examination, the specimens were interpreted semiquantitatively using Movin's grading scale and Bonar scores. Results: The highest mean forces were obtained in the HA group on Day 15 and in the VC group on Day 30, with a significant difference between HA and VC on Day 15 between control and VC on Day 30 (p<0.05). Histological examination showed both Movin and Bonar scores decreased in all groups on Day 30, with significant improvements in the HA and VC groups (p<0.05). Conclusion: Our results demonstrated that both VC and HA had therapeutic effects on tendon healing, especially in the late phase. Level of Evidence I; High quality randomized trial with statistically significant difference.


RESUMO Objetivo: Avaliar os efeitos histopatológicos e biomecânicos do ácido hialurônico (AH) e altas doses de vitamina C (VC) na cicatrização do tendão do calcâneo em ratos. Métodos: Quarenta e oito ratos Sprague-Dawley foram randomizados em grupo AH, grupo VC e grupo controle, iguais em número. Cada grupo foi dividido em dois subgrupos a serem sacrificados no Dia 15 (n = 8) e no Dia 30 (n = 8). Os tendões do calcâneo foram cortados e reparados. Enquanto os ratos do grupo controle permaneceram não tratados, os do grupo AH/VC receberam AH e VC após o reparo. Os tendões reparados foram removidos para análises biomecânicas e histopatológicas. Nos testes biomecânicos, os tendões foram estirados até a falha e as forças máximas foram medidas. No exame histopatológico, as amostras foram interpretadas semiquantitativamente usando os escores de Movin e de Bonar. Resultados: As forças médias mais altas foram obtidas no grupo AH no Dia 15 e no grupo VC, no Dia 30, com diferença significativa entre os grupos HA e VC no Dia 15 e entre os grupos controle e VC (p < 0,05). No exame histológico, os escores de Movin e Bonar diminuíram em todos os grupos no dia 30, com melhora significativas nos grupos AH e VC (p < 0,05). Conclusões: Nossos resultados demonstraram que tanto a VC quanto o AH tiveram efeitos terapêuticos sobre cicatrização do tendão, especialmente na fase tardia. Nível de Evidência I; Estudo clínico randomizado de alta qualidade com ou sem diferença estatisticamente significante.

20.
Comput Math Methods Med ; 2012: 803980, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22474539

RESUMEN

In our previous study, we have demonstrated that analyzing the skin impedances measured along the key points of the dermatomes might be a useful supplementary technique to enhance the diagnosis of spinal cord injury (SCI), especially for unconscious and noncooperative patients. Initially, in order to distinguish between the skin impedances of control group and patients, artificial neural networks (ANNs) were used as the main data classification approach. However, in the present study, we have proposed two more data classification approaches, that is, support vector machine (SVM) and hierarchical cluster tree analysis (HCTA), which improved the classification rate and also the overall performance. A comparison of the performance of these three methods in classifying traumatic SCI patients and controls was presented. The classification results indicated that dendrogram analysis based on HCTA algorithm and SVM achieved higher recognition accuracies compared to ANN. HCTA and SVM algorithms improved the classification rate and also the overall performance of SCI diagnosis.


Asunto(s)
Traumatismos de la Médula Espinal/diagnóstico , Adolescente , Adulto , Algoritmos , Inteligencia Artificial , Análisis por Conglomerados , Impedancia Eléctrica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Redes Neurales de la Computación , Sensibilidad y Especificidad , Piel/fisiopatología , Traumatismos de la Médula Espinal/clasificación , Máquina de Vectores de Soporte , Adulto Joven
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