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1.
Int J Sports Med ; 41(1): 59-64, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31752027

RESUMEN

The purpose of this study was to compare measures of bilateral shoulder and hip range of motion (ROM) between youth softball pitchers and position players. Fifty-two youth softball athletes (12.7±2.1 yrs.; 160.28±10.98 cm; 59.31±15.07 kg) participated. Bilateral hip and shoulder ROM were measured among pitchers (n=29) and position players (n=23). A 2 (pitcher/position player) × 2 (dominant/non-dominant) ANOVA was performed for both internal and external rotation ROM for the shoulder and hip. Paired sample t-tests were also conducted to examine side-to-side differences in total ROM. Data revealed a significant interaction between position and side dominance. Specifically, position players have significantly more non-dominant shoulder external rotation ROM (106.92°± 9.14°) than pitchers (100.12°± 11.21°). There were no significant differences between throwing and non-throwing sides. It is important that coaches and clinicians are aware of these adaptations between overhand and underhand throwing in order to properly develop conditioning and rehabilitation programs to alleviate injury susceptibility and cater to position-specific demands. Additionally, the current data suggest many of the functional adaptations seen within older populations are not fully developed until after youth.


Asunto(s)
Béisbol/fisiología , Articulación de la Cadera/fisiología , Articulación del Hombro/fisiología , Adaptación Fisiológica , Adolescente , Factores de Edad , Béisbol/lesiones , Niño , Femenino , Humanos , Rango del Movimiento Articular , Factores de Riesgo , Rotación
2.
World Neurosurg ; 133: 343-357.e1, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31550538

RESUMEN

BACKGROUND: The center of rotation (COR), instantaneous center of rotation (ICR), instantaneous axis of rotation, instantaneous helical axis, finite helical axis, and helical axis of motion are important kinematic parameters for evaluating the quality of intervertebral motion of the cervical spine (QIMC). These parameters embody different concepts and are calculated using various methods. In this review, the distinctions and connections between these kinematic parameters are analyzed according to the concepts, research, and measurement techniques to provide a theoretic basis for future research and new research directions. METHODS: The PubMed/MEDLINE databases were searched for studies published in English related to the concepts, research, and calculation of these parameters. The included studies were classified according to the different research or calculation methods, and the proportion of each study type was calculated and analyzed. RESULTS: Forty articles were selected. The methods for analyzing the QIMC include in vivo and in vitro studies and finite element analysis. The primary methods for calculating these parameters include the method of perpendicular bisectors and the finite helical axis method. CONCLUSIONS: COR was the simplest but not the most accurate parameter to evaluate the QIMC. Conversely, instantaneous helical axis/helical axis of motion were the most accurate, but relatively complex parameters to evaluate the QIMC. ICR showed dynamic changes during flexion-extension motion, but not the three-dimensional kinematic motion of the cervical spine. These parameters were equivalent only in certain situations but cannot be substituted for each other in the clinic. A dynamic radiographic in vivo study was the most convenient and frequently used research method to calculate COR, but failed to describe the dynamic movement. The method of perpendicular bisectors was widely used to calculate the COR or ICR. Therefore, a combination of new research and calculation methods to simply and effectively evaluate the QIMC requires further investigation.


Asunto(s)
Vértebras Cervicales/fisiología , Disco Intervertebral/fisiología , Rango del Movimiento Articular/fisiología , Fenómenos Biomecánicos/fisiología , Humanos , Rotación
3.
Zhongguo Gu Shang ; 32(11): 1044-1047, 2019 Nov 25.
Artículo en Chino | MEDLINE | ID: mdl-31870054

RESUMEN

OBJECTIVE: To investigate clinical effect of minimally invasive osteotomy and external fixation with the center of roration of angulation (CORA) in treating cubitus varus in adolescents. METHODS: From August 2013 to August 2017, 15 patients with cubitus varus caused by supracondylar fracture of humerus were treated with minimally invasive osteotomy and external fixation with the CORA. Among them, including 9 males and 6 females; 11 patients on the left side and 4 patients on the right side; aged from 13 to 16 years old with an average of 14.5 years old. The time from injury to operation was for 6 to 10 years with an average of 7.5 years. Five patients had a history of recurrence after cubitus varus surgery. Correction time. fracture healing time, carrying angle were observed, Laupattarakasem standard was used to evaluate clinical effect. RESULTS: All patients were followed up from 12 to 30 months with an average of 24 months; correction time ranged from 3 to 5 weeks with an average of 4 weeks; fracture healing time ranged from 4 to 6 months with an average of 5 months; carrying angle before operation ranged from -12° to -23°, and improved 9° to 14° after operation. According to Laupattarakasem evaluation criteria, 11 patients got an excellent result, 3 good and 1 fair. CONCLUSIONS: Minimally invasive osteotomy and external fixation with CORA in treating cubitus varus deformity in adolescents has advantages of less trauma, less blood loss, earlier exercise, speed and angle of correction could controlled without hospitalized for fixation.


Asunto(s)
Articulación del Codo , Fijación de Fractura , Fracturas del Húmero , Adolescente , Femenino , Humanos , Fracturas del Húmero/cirugía , Húmero , Masculino , Rotación
4.
Phys Rev Lett ; 123(13): 130001, 2019 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-31697547

Asunto(s)
Física , Rotación
5.
J Surg Orthop Adv ; 28(3): 201-208, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31675297

RESUMEN

The objective of this study was to determine which plane of hip motion (rotational or sagittal) is more predictive of lower extremity (LE) injury in elite soccer players. A total of 69 athletes (43 professional and 26 collegiate) were examined (mean age, 22.6 years). Bilateral hip internal rotation (IR), external rotation, extension, and flexion measurements were taken along with the modified Thomas test during preseason physicals. There were 42 LE injuries (injury rate 3.74/1000 athlete exposures). Mean IR was 25.2. and 29.9° for injured versus noninjured extremities, respectively (p = .009). There was a significant association between decreased IR (categorized as IR < 28°) and incidence of ipsilateral LE injury (p = .042). Extremities with IR < 28° were 2.81 times more likely to sustain a LE injury (95% CI, 1.15.6.84; p = .023). With a utilitarian focus, the current study has identified a measurement of decreased hip IR with potential for substantial clinical value in collegiate and professional soccer players. (Journal of Surgical Orthopaedic Advances 28(3):201-208, 2019).


Asunto(s)
Extremidad Inferior , Fútbol , Humanos , Extremidad Inferior/lesiones , Estudios Prospectivos , Rango del Movimiento Articular , Rotación , Fútbol/lesiones , Adulto Joven
6.
Plant Dis ; 103(12): 3093-3100, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31613191

RESUMEN

In Nebraska, rotation of soybean (Glycine max) fields to corn (Zea mays) is a major practice to manage the soybean cyst nematode (SCN; Heterodera glycines). However, factors associated with SCN population density decline during corn rotation are not clearly defined. This study addresses that question using a modeling approach. Seventy-nine fields were sampled in 2009, 2010, and 2011 to determine SCN population densities (eggs/100 cm3 of soil) before and after rotation. After rigorous field screening and model testing and validation, the regression model Log(Pf)^=-2.3360+0.8368LogPi+0.4333pH was developed, where Log Pf is the natural log of SCN eggs at the end of the rotation year, Pi is the population density before rotation, and pH is the soil pH. Model goodness-of-fit was assessed through residual analysis, information criteria, and other remedial measures. Model overdispersion was 1.04. Validation in a 50 and a 75% random sample from the original data set showed little change in model regression coefficients, standard errors, and associated significance, confirming model fit and performance. The model indicates that for one-unit increase in soil pH, SCN Pf is expected to increase by 53.7% at constant Pi, and correspondingly, a 10% change in Pi will result in about 8.3% change in Pf at constant soil pH. The model suggested that SCN population levels before corn rotation and soil pH are major determinants of observed SCN population density reduction after annual corn rotation in Nebraska. This model has potential for use in SCN risk analysis and in predicting SCN population decline after corn rotation in the state.


Asunto(s)
Agricultura , Nematodos , Suelo , Zea mays , Agricultura/métodos , Animales , Nebraska , Nematodos/fisiología , Enfermedades de las Plantas/parasitología , Enfermedades de las Plantas/prevención & control , Densidad de Población , Análisis de Regresión , Rotación , Suelo/parasitología , Zea mays/crecimiento & desarrollo , Zea mays/parasitología
7.
Zhongguo Gu Shang ; 32(9): 797-801, 2019 Sep 25.
Artículo en Chino | MEDLINE | ID: mdl-31615173

RESUMEN

OBJECTIVE: To study the effect of pelvic rotation in three-dimensional direction on the actual placement angle of acetabular prosthesis in total hip arthroplasty. METHODS: Pelvic CT imaging data of normal adults were collected, and three-dimensional reconstruction of pelvic acetabulum was performed with computer software to simulate the rotation of the pelvis around X, Y and Z axes perpendicular to the sagittal, transverse and coronal planes of the human body. Radiographic inclination(RI) and radiographic anteversion (RA) of the acetabular cup were measured when the acetabular prosthesis was implanted at a standard angle. The correlation analysis was used to quantify the relationship between the rotation angle of each axis and the actual angle of acetabulum. RESULTS: The pelvic rotation along the X-axis and Y-axis had little effect on the RA of the acetabulum, but had a great influence on the RI and showed a linear correlation. The regression equations were RA=0.682 4X+10.256(r²=0.308 4) and RA=-0.714 1Y+10.424(r²=0.999 8). The pelvic rotation along the Z-axis had little effect on the RA, but had a linear correlation with the RI, and the regression equation was RI=1.0Z+46(r²=1.0). CONCLUSIONS: The anteroposterior rotation of the pelvis or the longitudinal rotation along the body significantly affected the acetabular anteversion, but had little effect on the abduction angle. On the contrary, the left and right deviation of the pelvis on the coronal plane could significantly affect the acetabular anteversion angle, but did not affect its anteversion angle.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Acetábulo , Adulto , Humanos , Pelvis , Rotación
8.
J Pediatr Orthop ; 39(10): 521-526, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31599863

RESUMEN

BACKGROUND: Biplanar radiography with 3-dimensional (3D) modeling (EOS) provides a comprehensive assessment of lower limb alignment in an upright weight-bearing position with less radiation than conventional radiography. A study was performed to assess the consistency and reliability of 2 lower extremity 3D biplanar radiograph models created at least 1 year apart in a pediatric population. METHODS: All patients who had 2 lower extremity radiographic evaluations with EOS performed at visits a minimum of 1 year apart were reviewed. Digital radiographs, of lower extremities in both frontal and sagittal planes, were acquired simultaneously, using the EOS system. The 3D reconstruction of the images was achieved utilizing the SterEOS software. Pelvic position, femoral and tibial anatomy, and the torsional profile were evaluated and compared using t tests. RESULTS: In total, 53 patients with a mean age of 11.7 years (range, 6.1 to 18.9 y) met inclusion criteria. When comparing 3D models between visits, minimal differences were noted in proximal femoral anatomy and pelvic alignment (pelvic incidence, sacral slope, sagittal tilt, neck shaft angle). Expected differences in femoral and tibial length corresponded with normal longitudinal growth between visits. Sagittal plane knee position varied widely between examinations. Femoral and/or tibial rotational osteotomies were performed in 37% of extremities between examinations. After femoral derotational osteotomy, a significant difference in femoral anteversion was appreciated when comparing preoperative and postoperative 3D models. However, this difference was less than the expected difference based on the anatomic correction achieved intraoperatively. No differences were noted in tibial torsion measures after tibial derotational osteotomy. CONCLUSIONS: The 3D modeling based on biplanar radiographs provides consistent and reliable measures of pelvic and hip joint anatomy of the lower extremity. Patient positioning may influence the reproducibility of knee alignment. The torsional profile assessment did not accurately reflect changes obtained by derotational osteotomy. LEVEL OF EVIDENCE: Level III.


Asunto(s)
Articulación de la Cadera/diagnóstico por imagen , Imagen Tridimensional/métodos , Extremidad Inferior/diagnóstico por imagen , Huesos Pélvicos/diagnóstico por imagen , Adolescente , Niño , Simulación por Computador , Femenino , Fémur/diagnóstico por imagen , Fémur/cirugía , Humanos , Masculino , Osteotomía , Radiografía , Reproducibilidad de los Resultados , Rotación , Programas Informáticos , Tibia/diagnóstico por imagen , Tibia/cirugía , Factores de Tiempo
9.
Niger J Clin Pract ; 22(10): 1335-1340, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31607721

RESUMEN

Objective: The purpose of this study was to evaluate the cyclic fatigue resistances of the WaveOne Gold (WOG), ProTaper Next (PTN), 2Shape (TS) instruments. Materials and Methods: Totally 45 new WOG (25/.07), PTN (25/.06), TS (25/.06) files were tested inside the artificial canal of a custom-made stainless steel block with an inner diameter of 1.5 mm, a 60° angle, and a 5-mm radius of curvature. A 16-mm-long file segment (from the tip) was introduced and was immersed in 37°C water. The number of cycles to fracture (NCF), time to failure (TTF), fractured fragment length (FL) was recorded and the fractured surface was examined using microscope. Results: WOG > PTN > TS according to TTF results (P = 0.00). PTN > TS according to NCF results (P = 0.00). The FL values showed no significant difference (P = 0.335). Conclusions: Reciprocating motion can be used more safely than continuous rotation due to the higher cyclic fatigue resistance.


Asunto(s)
Aleaciones Dentales , Instrumentos Dentales , Preparación del Conducto Radicular/instrumentación , Temperatura Ambiental , Aleaciones , Análisis del Estrés Dental , Falla de Equipo , Oro , Humanos , Níquel , Rotación , Acero Inoxidable , Titanio
10.
J Environ Qual ; 48(4): 988-994, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31589683

RESUMEN

Successful N management practices for the US Midwest must optimize crop production and minimize NO-N losses from subsurface tile drainage. The objective of this study was to measure the effects of N rate, N application timing, and nitrapyrin [2-chloro-6-(trichlormethyl) pyridine] on corn ( L.) production and NO-N in tile drainage water in a corn-soybean [ (L.) Merr.] rotation in Minnesota. Anhydrous ammonia was applied at 90 and 179 kg ha with nitrapyrin in the fall and at 134 kg ha with and without nitrapyrin in fall and spring. However, drainage water monitoring was only conducted on fall treatments. Over a 5-yr period, 71% of drainage occurred in April through June and <1% occurred from November through March due to frozen soil. Averaged across N treatments and crops, annual drainage ranged from 69 to 380 mm among years. From 2001 through 2003, NO-N concentrations averaged 13.8, 15.6, and 20.0 mg L in corn and 7.3, 8.2, and 12.6 mg L in soybean when 90, 134, and 179 kg N ha was fall applied with nitrapyrin to corn, respectively. Corn grain yields were greater with spring-applied N at 134 kg ha (11.3 Mg ha) than with fall-applied N at 134 and 179 kg ha with nitrapyrin (10.5 and 10.8 Mg ha, respectively), and nitrapyrin did not affect corn production or water quality. Fall application of N is common on cold soils in Minnesota. These data showed that fall application required a greater rate of N to optimize yield than spring and that greater fall rate often increased NO-N concentration and load in tile drainage water.


Asunto(s)
Soja , Zea mays , Agricultura , Fertilizantes , Minnesota , Nitratos , Nitrógeno , Picolinas , Rotación , Suelo
11.
Am J Vet Res ; 80(10): 943-949, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31556713

RESUMEN

OBJECTIVE: To determine the holding capacity of a 5.5-mm-diameter cortical bone screw when placed in the third phalanx (P3) of horses and assess whether screw placement through the dorsal hoof wall into P3 would be tolerated by clinically normal horses and would alleviate signs of pain and prevent P3 rotation in horses with oligofructose-induced laminitis. ANIMALS: 40 limbs from 10 equine cadavers and 19 clinically normal adult horses. PROCEDURES: In part 1 of a 3-part study, a 5.5-mm-diameter cortical bone screw was inserted by use of a lag-screw technique through the dorsal hoof wall midline into P3 of 40 cadaveric limbs and tested to failure to determine screw pullout force. In part 2, 6 horses had 5.5-mm-diameter cortical bone screws placed in both forefeet as described for part 1. Screws were removed 4 days after placement. Horses were monitored for lameness before and for 2 weeks after screw removal. In part 3, 13 horses were randomly assigned to serve as controls (n = 3) or undergo screw placement without (group 2; 6) or with (group 3; 4) a washer. Following the acquisition of baseline data, horses were sedated and administered oligofructose (10 g/kg) via a stomach tube. Twenty-four hours later, screws were placed as previously described in both forefeet of horses in groups 2 and 3. Horses were assessed every 4 hours, and radiographic images of the feet were obtained at 96 and 120 hours after oligofructose administration. Horses were euthanized, and the feet were harvested for histologic examination. RESULTS: The mean ± SD screw pullout force was 3,908.7 ± 1,473.4 N, and it was positively affected by the depth of screw insertion into P3. Horses of part 2 tolerated screw placement and removal well and did not become lame. All horses of part 3 developed signs of acute lameness, and the distance between P3 and the dorsal hoof wall increased slightly over time. The change in the ratio of the dorsal hoof wall width at the extensor process of P3 to that at the tip of P3 over time was the only variable significantly associated with treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Placement of a 5.5-mm-diameter cortical bone screw through the dorsal hoof wall into P3 had sufficient holding power to counteract the pull of the deep digital flexor tendon in approximately 500-kg horses, and placement of such a screw was well tolerated by clinically normal horses but did not alleviate signs of pain in horses with oligofructose-induced laminitis. Further research is necessary before this technique can be recommended for horses with naturally occurring acute laminitis.


Asunto(s)
Tornillos Óseos/veterinaria , Enfermedades del Pie/veterinaria , Pezuñas y Garras/cirugía , Enfermedades de los Caballos/cirugía , Cojera Animal/cirugía , Animales , Femenino , Enfermedades del Pie/cirugía , Miembro Anterior , Enfermedades de los Caballos/inducido químicamente , Caballos , Masculino , Oligosacáridos/efectos adversos , Distribución Aleatoria , Rotación
12.
J Appl Biomech ; 35(5): 344-352, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31541064

RESUMEN

Functional knee braces are frequently prescribed by physicians to ameliorate the function of individuals with anterior cruciate ligament (ACL) injuries. These braces have been shown in the literature to potentially enhance knee stability by augmenting muscle activation patterns and the timing of muscle response to perturbations. However, very few techniques are available in the literature to quantify how those modifications in lower-limb muscle activity influence stability of the knee. The aim of the present study was to quantify the effect of an off-the-shelf functional knee brace on muscle contributions to knee joint rotational stiffness in ACL-deficient and ACL-reconstructed patients. Kinematic, electromyography, and kinetic data were incorporated into an electromyography-driven model of the lower extremity to calculate individual and total muscle contributions to knee joint rotational stiffness about the flexion-extension axis, for 4 independent variables: leg condition (contralateral uninjured, unbraced ACL injured, and braced ACL injured); knee flexion (5°-10°, 20°-25°, and 30°-35°); squat stability condition (stable and unstable); and injury status (ACL deficient and ACL reconstructed). Participants had significantly higher (P < .05, η2 = .018) total knee joint rotational stiffness values while wearing the brace compared with the control leg. A 2-way interaction effect between stability and knee flexion (P < .05, η2 = .040) for total joint rotational stiffness was also found.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/fisiopatología , Tirantes , Articulación de la Rodilla/fisiopatología , Rango del Movimiento Articular , Adulto , Electromiografía , Humanos , Masculino , Músculo Esquelético/fisiología , Rotación , Adulto Joven
13.
J Mol Model ; 25(10): 312, 2019 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-31511986

RESUMEN

Perampanel approved by FDA in 2012 is a first-in-class antiepileptic drug which inhibits α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor currents. It is markedly more active than many of its close analogs, and the reasons for this activity difference are not quite clear. Recent crystallographic studies allowed the authors to identify the location of its binding site. Unfortunately, the resolution is low, and the detailed description of perampanel binding mode is still in part speculative. Here we provide a detailed DFT-level conformational analysis of perampanel in a vacuum and in the solvents, mimicking the protein environment, followed by quantum theory of atoms in molecules (QTAIM), non-covalent interactions (NCI), and natural bond orbital (NBO) analyses. The findings indicate the electrostatic nature of the intramolecular interactions which contribute to energy differences of the conformations in a vacuum whereas the increase of dielectric constant leads to the energy equalization of conformations. Based on these results, the docking study was performed to investigate possible binding modes of perampanel and its close analogs in AMPA receptors. The influence of the pyridine nitrogen and cyano group position was explained based on the results of conformational analysis and molecular docking. These findings may contribute to the design of novel antiepileptic drugs and the development of novel approaches to treat neurodegenerative diseases and major depressive disorder.


Asunto(s)
Teoría Funcional de la Densidad , Antagonistas de Aminoácidos Excitadores/química , Conformación Molecular , Simulación del Acoplamiento Molecular , Piridonas/química , Rotación , Electricidad Estática , Termodinámica
14.
Comput Methods Biomech Biomed Engin ; 22(16): 1239-1246, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31553277

RESUMEN

Needle insertion plays an important part in the process of corneal graft surgery. In this paper, a three-dimensional symmetry model of the human cornea is constructed using the finite element method. Simplification of specific optic physiology is defined for the model: The cornea constrained by the sclera is presented as two layers consisting of epithelium and stroma. A failure criterion based on the distortion energy theory has been proposed to predict the insertion process of the needle. The simulation results show a good agreement with the experimental data reported in the literature. The influence of needling conditions (e.g. insertion velocity, rotation parameters and vibration parameters) on the insertion force are then discussed. In addition, a multi-objective optimization based on particle swarm optimization (PSO) is applied to reduce the insertion force. The numerical results provide guidelines for selecting the motion parameters of the needle and a potential basis for further developments in robot-assisted surgery.


Asunto(s)
Córnea/fisiología , Agujas , Fenómenos Biomecánicos , Simulación por Computador , Córnea/anatomía & histología , Humanos , Rotación , Vibración
15.
Artículo en Inglés | MEDLINE | ID: mdl-31527403

RESUMEN

(1) Background: Idiopathic scoliosis is a deformity of the growing spine. It affects 2-3% of adolescents; yet its cause is still unknown. At the early stage of idiopathic scoliosis (IS), the signs are not very noticeable. That is why the primarily school-based screening for scoliosis is so important. (2) Methods: This was a cross-sectional analysis of 6850 respondents. Participants were elementary school students in the metropolitan area of Poland. The suspicion of IS was based on detection of three-dimensional deformity of the spine using scoliometer. (3) Results: Respondents were divided into two groups: Angle of trunk rotation (ATR) = 0-3º and ATR > 3º. Presented research using a referral criterion of 5º ATR showed that in the group of participants who had ATR > 3º the largest percentage of 5 degree values was recorded at the second and third measurement level of the spine (30.5%, 31.1%, respectively). Analyzing the differences between the two groups of girls (ATR = 0-3º, ATR > 3º), statistically significant differences were recorded between 9 and 11 years of age (p = 0.0388). Girls with ATR > 3º at all measuring levels are significantly slimmer than girls with ATR 0-3º; (4) Conclusions: Age; sex, and risk of developing angle of trunk rotation are very closely associated. The main thoracic (level 2) and thoraco-lumbar (level 3) level of measuring of the spine appears to be the most differentiating in the diagnosis of scoliosis. Girls with a lower degree of trunk deformity (4-6º trunk rotation), which can present mild scoliosis and those with a higher degree (7º trunk rotation) have lower body mass than girls within the norm.


Asunto(s)
Escoliosis/diagnóstico , Escoliosis/epidemiología , Adolescente , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Tamizaje Masivo/métodos , Polonia/epidemiología , Prevalencia , Rotación , Columna Vertebral/anomalías
16.
Acta Chir Orthop Traumatol Cech ; 86(4): 249-255, 2019.
Artículo en Checo | MEDLINE | ID: mdl-31524585

RESUMEN

PURPOSE OF THE STUDY The purpose of the study was to evaluate tibio-femoral rotation during a simulated squat and to investigate the relationship between the rotational position of the femur in full extension and the amount of external rotation of the femur on the tibia during flexion. MATERIAL AND METHODS Part 1: MRIs of volunteers Data on healthy knees of 10 volunteers were obtained using 2D MRI measurements. The foot and the ankle were fixed to prevent rotation and adduction/abduction movements. Sagittal MRIs of the knees have been performed in 4 positions of flexion. The amount of longitudinal rotation in each position of flexion was calculated. Part 2: Mathematical model experiment a) The model of the femur has been positioned in the 3D coordinate system in full extension and at 12.8° of internal rotation and then flexed to 90° without longitudinal rotation. The distance between the centre of the femoral head and the sagittal plane passing through the centre of the knee was then measured. b) Subsequently, the femur was flexed and rotation allowed to retain femoral head within the sagittal plane. The amount of femoral rotation was then calculated. RESULTS Part 1: In full extension the femur was on average in 12.8° of IR relative to the tibia. By 90° flexion femur rotated on average 12.2° externally. Part 2: a)From full extension to 90° flexion the femoral head moved 93.1 mm laterally from the sagittal plane. b)Between full extension and 90° flexion the femur rotated 12.8° externally, a degree which corresponds to the amount of initial internal rotation of the femur in full extension. DISCUSSION The most important finding of the presented in vivo study lies in the fact that in normal knees with tibia rotationally fixed flexion is always coupled with femoral external rotation in order to keep the femoral head in the acetabulum. This rotation is obligatory. CONCLUSIONS We have demonstrated that if the tibia is rotationally fixed, the knee flexion is possible only when accompanied by femoral external rotation to keep the femoral head in the acetabulum. A mathematical description of the experiment has been proposed, the results of which confirm the stated premise. This finding can be explained by initial internal rotation of the femur in full extension of the knee and is allowed by the shape of articulating bones and tension of soft tissues Key words: knee, terminal extension, knee rotation, knee movement, MRI, hip joint.


Asunto(s)
Articulación de la Rodilla/diagnóstico por imagen , Fenómenos Biomecánicos , Fémur/diagnóstico por imagen , Fémur/fisiología , Humanos , Articulación de la Rodilla/fisiología , Imagen por Resonancia Magnética , Modelos Biológicos , Rango del Movimiento Articular , Rotación , Tibia/diagnóstico por imagen , Tibia/fisiología
17.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(10): 1228-1233, 2019 Oct 15.
Artículo en Chino | MEDLINE | ID: mdl-31544430

RESUMEN

Objective: To measure the rotation angle of the head-neck fragment of intertrochanteric fracture after cephalomedullary nail fixation by three-dimensional CT imaging, and to explore its clinical significance. Methods: The clinical data of 68 patients with unstable intertrochanteric fracture of AO/Orthopaedic Trauma Association (AO-OTA) type 31-A2 treated with cephalomedullary nail fixation and with complete intraoperative fluoroscopy and postoperative three-dimensional CT imaging data between July 2016 and October 2018 were retrospectively analyzed. Among them, there were 21 males and 47 females, aged 68-93 years, with an average age of 81.8 years. There were 31 cases of AO/OTA type 31-A2.2 and 37 cases of 31-A2.3. Fracture reduction quality was evaluated according to Baumgaertner et al. and Chang et al. criteria. The anteromedial cortical contact or not of each patient was observed by three-dimensional CT imaging on T3DView software after operation. The rotation of head-neck fragments were divided into three types: non-rotation, flexion rotation, and hyperextension rotation. The rotation angles of each type were measured and the relationship between the rotation type of the head-neck fragments and the contact of the anteromedial cortex was analyzed. Results: The reduction and fixation of the small trochanter were not performed in 68 patients. According to Baumgaertner et al. criteria, the quality of fracture reduction was excellent in 15 cases (22.1%), acceptable in 50 cases (73.5%), and poor in 3 cases (4.4%). According to Chang et al. criteria, 31 cases were excellent (45.6%), 33 cases were acceptable (48.5%), and 4 cases were poor (5.9%). Thirty-nine cases (57.4%) received anteromedial cortical support and 29 cases (42.6%) did not receive cortical support. Three-dimensional CT imaging showed non-rotation in 12 cases (17.6%), flexion rotation in 39 cases (57.4%), and hyperextension rotation in 17 cases (25.0%). There were 7 cases (58.3%), 30 cases (76.9%), and 2 cases (11.8%) of cortical support in non-rotation group, flexion rotation group, and hyperextension rotation group, respectively. The rotation angles were (1.05±0.61), (13.96±6.17), (8.21±3.88)°, respectively. There were significant differences between groups ( P<0.05). Conclusion: In the unstable intertrochanteric fracture after cephalomedullary nail fixation, the rotation of head-neck fragment exists in most patients, and the types of flexion rotation and non-rotation can easily obtain cortical support reduction.


Asunto(s)
Fijación Intramedular de Fracturas , Fracturas de Cadera , Anciano , Anciano de 80 o más Años , Clavos Ortopédicos , Femenino , Fémur , Humanos , Masculino , Estudios Retrospectivos , Rotación , Resultado del Tratamiento
18.
Clin Orthop Surg ; 11(3): 309-315, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31475052

RESUMEN

Background: Minimal rotation of the scapula may affect the measurement of critical shoulder angle (CSA). We investigated the difference in the CSA measured in minimal rotation between the patients with rotator cuff tear and those without non-rotator cuff tear and the CSA measurement error by comparing with computed tomography (CT). Methods: We retrospectively reviewed patients with full-thickness rotator cuff tear and whose X-ray views correspond to Suter-Henninger classification type A1 and C1. The CSA values between the normal control group (without rotator cuff tear) and the rotator cuff tear group were compared according to A1 type and C1 type. In the rotator cuff tear group, we compared the CSA values measured by using X-ray and CT. Results: A total of 238 patients (rotator cuff tear group, 139 patients; normal cuff group, 99 patients) were included in this study. The mean CSA of the rotator cuff tear group was 33.4° ± 3.5°, and that of the normal cuff group was 32.6° ± 3.9° (p = 0.085). On comparison of the CSA according to the Suter-Henninger classification type, the CSA values on the A1 type view and C1 type view were 32.7° ± 3.5° and 33.7° ± 3.5°, respectively, in the rotator cuff tear group and 30.5° ± 3.1° and 33.1 ± 3.9°, respectively, in the normal cuff group (p = 0.024 and p = 0.216, respectively). The mean CSA was 32.5° ± 3.1° in CT and 33.3° ± 3.2° in X-ray (p = 0.184). On comparison of the CSA according to the Suter-Henninger classification type, the CSA values on the A1 type view and C1 type view were 32.6° ± 3.6° and 32.5° ± 2.4°, respectively, in CT and 32.5° ± 3.5° and 34.2° ± 2.6°, respectively, in X-ray (p = 0.905 and p = 0.017, respectively). Conclusions: The X-ray view corresponding to Suter-Henninger classification type A1 or CT-reconstructed image can be used to reduce the measurement error and obtain reliable CSA values. The CSA measured on the X-ray view corresponding to Suter-Henninger classification type A1 may be related with rotator cuff tear.


Asunto(s)
Lesiones del Manguito de los Rotadores/diagnóstico por imagen , Escápula/diagnóstico por imagen , Articulación del Hombro/diagnóstico por imagen , Acromion/diagnóstico por imagen , Acromion/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Estudios Retrospectivos , Rotación , Lesiones del Manguito de los Rotadores/fisiopatología , Escápula/fisiopatología , Articulación del Hombro/fisiopatología , Tomografía Computarizada por Rayos X
19.
Nat Methods ; 16(9): 802, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31471612

Asunto(s)
ADN , Rotación
20.
Sports Health ; 11(6): 535-542, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31478791

RESUMEN

BACKGROUND: The variability of throwing metrics, particularly elbow torque and ball velocity, during structured long-toss programs is unknown. HYPOTHESES: (1) Elbow torque and ball velocity would increase as throwers progressed through a structured long-toss program and (2) intrathrower reliability would be high while interthrower reliability would be variable. STUDY DESIGN: Descriptive laboratory study. LEVEL OF EVIDENCE: Level 3. METHODS: Sixty healthy high school and collegiate pitchers participated in a structured long-toss program while wearing a validated inertial measurement unit, which measured arm slot, arm velocity, shoulder rotation, and elbow varus torque. Ball velocity was assessed by radar gun. These metrics were compared within and between all pitchers at 90, 120, 150, and 180 ft and maximum effort mound pitching. Intra- and interthrower reliabilities were calculated for each metric at every stage of the program. RESULTS: Ball velocity significantly changed at each progressive throwing distance, but elbow torque did not. Pitching from the mound did not place more torque on the elbow than long-toss throwing from 120 ft and beyond. Intrathrower reliability was excellent (intraclass correlation coefficient >0.75) throughout the progressive long-toss program, especially on the mound. Ninety-one percent of throwers had acceptable interthrower reliability (coefficient of variation <5%) for ball velocity, whereas only 79% of throwers had acceptable interthrower reliability for elbow torque. CONCLUSION: Based on trends in elbow torque, it may be practical to incorporate pitching from the mound earlier in the program (once a player is comfortable throwing from 120 ft). Ball velocity and elbow torque do not necessarily correlate with one another, so a degree of caution should be exercised when using radar guns to estimate elbow torque. Given the variability in elbow torque between throwers, some athletes would likely benefit from an individualized throwing program. CLINICAL RELEVANCE: Increased ball velocity does not necessarily equate to increased elbow torque in long-toss. Some individuals would likely benefit from individualized long-toss programs for rehabilitation.


Asunto(s)
Béisbol/fisiología , Codo/fisiología , Acondicionamiento Físico Humano/métodos , Brazo/fisiología , Traumatismos en Atletas/rehabilitación , Béisbol/lesiones , Fenómenos Biomecánicos , Monitores de Ejercicio , Humanos , Rotación , Hombro/fisiología , Equipo Deportivo , Torque , Ejercicio de Calentamiento , Dispositivos Electrónicos Vestibles , Adulto Joven
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