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1.
Arthroscopy ; 40(2): 424-434.e3, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37422027

RESUMO

PURPOSE: To identify risk factors for patients who sustain nontraumatic anterior cruciate ligament reconstruction (ACLR) failure. METHODS: A retrospective analysis was performed on patients undergoing primary or revision ACLR in our institution between 2010 and 2018. Patients sustaining insidious-onset knee instability without history of trauma were identified as nontraumatic ACLR failure and assigned to the study group. The control group of subjects who showed no evidence of ACLR failure with minimum 48-month follow-up were matched in a 1:1 ratio based on age, sex, and body mass index. Anatomic parameters including tibial slope (lateral [LTS], medial [MTS]); tibial plateau subluxation (lateral [LTPsublx], medial [MTPsublx]); notch width index (NWI); and lateral femoral condyle ratio were measured with magnetic resonance imaging or radiography. Graft tunnel position was assessed using 3-dimensional computed tomography and reported in 4 dimensions: deep-shallow ratio (DS ratio) and high-low ratio for femoral tunnel, anterior-posterior ratio and medial-lateral ratio for tibial tunnel. Interobserver and intraobserver reliability were evaluated by the intraclass correlation coefficient (ICC). Patients' demographic data, surgical factors, anatomic parameters, and tunnel placements were compared between the groups. Multivariate logistic regression and receiver operating characteristic curve analysis was used to discriminate and assess the identified risk factors. RESULTS: A total of 52 patients who sustained nontraumatic ACLR failure were included and matched with 52 control subjects. Compared to patients with intact ACLR, those who sustained nontraumatic ACLR failure showed significantly increased LTS, LTPsublx, MTS, and deceased NWI (all P < .001). Moreover, the average tunnel position in the study group was significantly more anterior (P < .001) and superior (P = .014) at the femoral side and more lateral (P = .002) at the tibial side. Multivariate regression analysis identified LTS (odds ratio [OR] = 1.313; P = .028), DS ratio (OR = 1.091; P = .002), and NWI (OR = 0.813; P = .040) as independent predictors of nontraumatic ACLR failure. LTS appeared to be the best independent predictive factor (area under the curve [AUC] = 0.804; 95% confidence interval [CI], 0.721-0.887), followed by DS ratio (AUC = 0.803; 95% CI, 0.717-0.890), and NWI (AUC = 0.756; 95% CI, 0.664-0.847). The optimal cutoff values were 6.7° for increased LTS (sensitivity = 0.615, specificity = 0.923); 37.4% for increased DS ratio (sensitivity = 0.673, specificity = 0.885); and 26.4% for decreased NWI (sensitivity = 0.827, specificity = 0.596). Intraobserver and interobserver reliability was good to excellent, with ICCs ranging from 0.754 to 0.938 for all radiographical measurements. CONCLUSIONS: Increased LTS, decreased NWI, and femoral tunnel malposition are predictive risk factors for nontraumatic ACLR failure. LEVEL OF EVIDENCE: Level III, retrospective comparative study.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Humanos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Estudos de Casos e Controles , Lesões do Ligamento Cruzado Anterior/complicações , Lesões do Ligamento Cruzado Anterior/cirurgia , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Articulação do Joelho/cirurgia , Imageamento por Ressonância Magnética , Reconstrução do Ligamento Cruzado Anterior/métodos , Fatores de Risco
2.
Arthroscopy ; 2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37813203

RESUMO

PURPOSE: To investigate the association between lateral femoral condyle ratio (LFCR) measured by magnetic resonance imaging (MRI) and anterior cruciate ligament (ACL) rerupture after anatomic ACL reconstruction (ACLR) and to compare the diagnostic accuracy between MRI and radiograph measurements. METHODS: A retrospective review was conducted on patients who underwent anatomic ACLR in our institution between 2015 and 2018. Patients who experienced rerupture after ACLR were identified and matched 1:1 with control patients who showed no evidence of graft failure during a minimum 48-month follow-up. The matching criteria included age, sex, and body mass index. LFCR was measured on MRI scans and radiographs of the affected limb. Patients' characteristics, surgical features, and anatomic measurements were compared between groups. Conditional logistic regression was performed to investigate whether MRI-measured LFCR is a risk factor for ACL rerupture. The optimal cutoff value was determined by receiver operating characteristic curves (ROC). Delong's test was performed to compare the diagnostic accuracy between MRI and radiograph measurements. RESULTS: A total of 72 patients who sustained ACL rerupture were included and matched with 72 control subjects. Compared to patients with intact ACLR, those who sustained ACL rerupture showed a significant increase in LFCR on MRI scans (63.38% ± 2.26% [95% CI, 62.84%-63.91%] vs 61.10% ± 2.19% [95% CI, 60.59%-61.61%], P < .001). An MRI-measured LFCR >62.18% was set as the cutoff point to discern patients at a higher risk of graft failure after anatomic ACLR, with sensitivity and specificity of 75.0% and 70.8%, respectively. MRI-measured LFCR demonstrated superior diagnostic accuracy during ROC curve analysis, achieving a higher area under the curve compared to radiograph-measured LFCR (0.783 ± 0.051 vs 0.668 ± 0.060, P = .041). CONCLUSIONS: The study found that MRI-measured LFCR was associated with ACL rerupture. A cutoff value of 62.18% was determined, which can help identify patients at a higher risk of rerupture. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

3.
Front Public Health ; 12: 1305924, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38299072

RESUMO

Objective: As two line trends - aging disability and disability aging - continue to emerge, hearing disability is becoming increasingly prevalent among older adults in china. This study aimed to investigate the incidence of hearing disability among older adults and identify the various factors contributing to its development. Methods: In this matched nested case-control study, data from the China Health and Retirement Longitudinal Study from 2011 to 2018 were analyzed. A total of 4,523 older adults were recruited from a national sample database, of which 1,094 individuals were eligible for inclusion in the hearing disability cohort, while 3,429 older adults who had not been diagnosed with hearing disability were considered non-hearing disability controls. Hearing disability was assessed by a self-reported question. These controls were matched to hearing disability cases in a 1:1 ratio based on age and sex. The logistic regression models were used to find out various factors of hearing disability in the target population. Results: Totally 1,094 individuals (24.14%) developed hearing disability during the follow-up period. After 1:1 matching, 2,182 subjects were included in the study, with 1,091 cases in the case group. Factors that influenced the incidence of hearing disability in older adults included annual per capita household income (OR = 0.985, p = 0.003), cognitive function (OR = 0.982, p = 0.015), depression level (OR = 1.027, p < 0.001), somatic mobility (OR = 0.946, p = 0.007), history of kidney disease (OR = 1.659, p < 0.001), history of asthma (OR = 1.527, p = 0.008), history of accidental injuries (OR = 1.348, p = 0.015), whether there is a place for recreational and fitness activities in the community (OR = 0.672, p < 0.001), and whether there is a health service center/health center in the community (OR = 0.882, p = 0.006). Conclusion: The incidence of hearing disabilities among older adults in China is high. The protective and risk factors that contribute to the incidence of disability should be fully considered in the care of older adults.


Assuntos
Envelhecimento , Audição , Humanos , Idoso , Estudos Longitudinais , Estudos de Casos e Controles , China/epidemiologia
4.
J Multidiscip Healthc ; 17: 2331-2350, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38770173

RESUMO

Purpose: To conducted a scoping review of care needs of older adults with disabilities at home and in the community and provide a comprehensive understanding of the essential needs of older adults with disabilities. Methods: Eight databases were searched for relevant Chinese and English studies (supplemented by retrospective references of the included studies) from the establishment of the database to February 13, 2023. An thematic synthesis approach was used to qualitatively integrate the retrieved studies and identify need-related themes. Results: A total of 6239 studies were retrieved, 2557 were de-weighted and excluded, and 56 were obtained after the double screening. Studies were from 11 countries. Thirty-three studies used a self-prepared survey instrument to investigate needs, and the other research tools commonly used were secondary databases and the Long-Term Care Needs of the Disabled Scale. A total of 78 specific need items were identified and summarized into three need themes based on the ICF framework: physical functioning needs, activity and participation needs, and environment needs. Conclusion: The complex physical and mental health conditions faced by older adults with disabilities result in multifaceted, integrated needs that are difficult to identify and meet. Current research on older adults with disabilities is limited to common care. Future research should focus on the specificities of the older disabled population and understand the diverse care needs of people with disabilities in order to better target care services for this group. Policymakers should formulate more operational and strategic measures based on the actual needs of older adults with disabilities to expand the coverage of services and to pinpoint care services.

5.
Chaos ; 22(4): 043132, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23278067

RESUMO

We investigate the dynamics of the bound vector solitons (BVSs) for the coupled nonlinear Schrödinger equations with the nonhomogenously stochastic perturbations added on their dispersion terms. Soliton switching (besides soliton breakup) can be observed between the two components of the BVSs. Rate of the maximum switched energy (absolute values) within the fixed propagation distance (about 10 periods of the BVSs) enhances in the sense of statistics when the amplitudes of stochastic perturbations increase. Additionally, it is revealed that the BVSs with enhanced coherence are more robust against the perturbations with nonhomogenous stochasticity. Diagram describing the approximate borders of the splitting and non-splitting areas is also given. Our results might be helpful in dynamics of the BVSs with stochastic noises in nonlinear optical fibers or with stochastic quantum fluctuations in Bose-Einstein condensates.

6.
Phys Rev E ; 100(4-1): 042210, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31770880

RESUMO

Investigated in this paper is a quasigeostrophic two-layer model for the wave packets in a marginally stable or unstable baroclinic shear flow. We find that the wave packets can be modulated by certain long waves, resulting in different behaviors from those in the existing literature. Via the bilinear method, we construct the modulated Nth-order (N=1,2,...) solitary waves, breathers, and rogue waves for the wave-packet equations. Based on the modulation effects of the long waves, the solitary waves are classified into three types, i.e., Type-I, Type-II, and Type-III solitary waves. Type-I solitary waves, without the modulations, are the bell shaped and propagate with constant velocities; Type-II solitary waves, with the weak modulations, are shape changing within a short time and subsequently return to the bell-shaped state; and Type-III solitary waves, with the strong modulations, show not only the variations of shapes but also the appearances, splits, combinations, and disappearances of certain bulges in the evolution. For the interaction between the two unmodulated solitary waves, two Type-I solitary waves can bring about the oscillations in the interaction zone when they possess different velocities, and bring into being the bound-state, oscillation-state, and bi-oscillation-state solitary waves when they possess the same velocity. For the two interactive modulated solitary waves, bound-state, oscillation-state, and bi-oscillation-state solitary waves with the short-time variations of shapes or appearances of bulges can occur. Due to the modulations of the long waves, breathers and rogue waves are distorted and stretched, mainly in two aspects: one is the evolution trajectories for the breathers; the other is the shape variations for each element of the breathers and rogue waves. Numbers of the peaks and valleys for the rogue waves are adjustable via the modulations. In addition, modulated breathers and rogue waves can degenerate into the M- or W-shaped or multipeak solitary waves under certain conditions.

7.
Artigo em Inglês | MEDLINE | ID: mdl-25019859

RESUMO

To investigate nonautonomous matter waves with time-dependent modulation in a one-dimensional trapped spin-1 Bose-Einstein condensate, we hereby work on the generalized three-coupled Gross-Pitaevskii equations by means of the Hirota bilinear method. By modulating the external trap potential, atom gain or loss, and coupling coefficients, we can obtain several nonautonomous matter-wave solitons and rogue waves including "bright" and "dark" shapes and arrive at the following conclusions: (i) the external trap potential and atom gain or loss can influence the propagation of matter-wave solitons and the duration and frequency of bound solitonic interaction, but they have little effect on the head-on solitonic interaction; (ii) through numerical simulation, stable evolution of the matter-wave solitons is realized with a perturbation of 5% initial random noise, and the spin-exchange interaction of atoms can be affected by the time-dependent modulation; (iii) under the influence of a periodically modulated trap potential and periodic atom gain or loss, rogue waves can emerge in the superposition of localized character and periodic oscillating properties.


Assuntos
Modelos Teóricos , Simulação por Computador , Periodicidade , Tempo
8.
Artigo em Inglês | MEDLINE | ID: mdl-24329372

RESUMO

A generalized inhomogeneous Gardner model with an external force term is investigated which can govern the soliton propagation and interaction in the vicinity of the negative ion critical density for certain plasmas or of equal layer depths for stratified fluids. Integrable aspects including the Lax pair and the Γ-Riccati-type Bäcklund transformation (Γ-R BT) are presented under the Painlevé conditions. By virtue of the Γ-R BT, analytic one- or two-soliton-like solutions with the inhomogeneous coefficients, external force term, eigenvalue in the Lax pair, and another parameter are obtained. Analytic analysis and graphic illustration imply that (1) the amplitude of a soliton is influenced by the quadratic and cubic nonlinear coefficients, the linear-damping coefficient, and the aforementioned eigenvalue; (2) the solitonic velocity is "controlled" by the inhomogeneous coefficients, the external force term, and the aforementioned eigenvalue and parameter; (3) the solitonic background is affected by the linear-damping coefficient, the external force term and the aforementioned parameter; and (4) the possibility of solitonic infection is dominated by the difference between eigenvalues.

9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 83(5 Pt 2): 056601, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21728676

RESUMO

Under investigation is a generalized variable-coefficient forced Korteweg-de Vries equation in fluids and other fields. From the bilinear form of such equation, the N-soliton solution and a type of analytic solution are constructed with symbolic computation. Analytic analysis indicates that: (1) dispersive and dissipative coefficients affect the solitonic velocity; (2) external-force term affects the solitonic velocity and background; (3) line-damping coefficient and some parameters affect the solitonic velocity, background, and amplitude. Solitonic propagation and interaction can be regarded as the combination of the effects of various variable coefficients. According to a constraint among the nonlinear, dispersive, and line-damping coefficients in this paper, the possible applications of our results in the real world are also discussed in three aspects, i.e., solution with the constraint, solution without the constraint, and approximate solution.

10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 84(2 Pt 2): 026606, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21929127

RESUMO

The concept of soliton management has been explored in the Bose-Einstein condensate and optical fibers. In this paper, our purpose is to investigate whether a similar concept exists for a variable-coefficient modified Korteweg-de Vries equation, which arises in the interfacial waves in two-layer liquid and Alfvén waves in a collisionless plasma. Through the Painlevé test, a generalized integrable form of such an equation has been constructed under the Painlevé constraints of the variable coefficients based on the symbolic computation. By virtue of the Ablowitz-Kaup-Newell-Segur system, a Lax pair with time-dependent nonisospectral flow of the integrable form has been established under the Lax constraints which appear to be more rigid than the Painlevé ones. Under such Lax constraints, multisoliton solutions for the completely integrable variable-coefficient modified Korteweg-de Vries equation have been derived via the Hirota bilinear method. Moreover, results show that the solitons and breathers with desired amplitude and width can be derived via the different choices of the variable coefficients.

11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 80(6 Pt 2): 066608, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20365295

RESUMO

Dynamic features describing the collisions of the bound vector solitons and soliton complexes are investigated for the coupled nonlinear Schrödinger (CNLS) equations, which model the propagation of the multimode soliton pulses under some physical situations in nonlinear fiber optics. Equations of such type have also been seen in water waves and plasmas. By the appropriate choices of the arbitrary parameters for the multisoliton solutions derived through the Hirota bilinear method, the periodic structures along the propagation are classified according to the relative relations of the real wave numbers. Furthermore, parameters are shown to control the intensity distributions and interaction patterns for the bound vector solitons and soliton complexes. Transformations of the soliton types (shape changing with intensity redistribution) during the collisions of those stationary structures with the regular one soliton are discussed, in which a class of inelastic properties is involved. Discussions could be expected to be helpful in interpreting such structures in the multimode nonlinear fiber optics and equally applied to other systems governed by the CNLS equations, e.g., the plasma physics and Bose-Einstein condensates.


Assuntos
Biofísica/métodos , Algoritmos , Simulação por Computador , Modelos Estatísticos , Modelos Teóricos , Dinâmica não Linear
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