Carlos Dias Maciel

The effect of additional strengthening of hip abductor and lateral rotator muscles in patellofemoral pain syndrome: a randomized controlled pilot study

Objectives: To study the effect of additional strengthening of hip abductor and lateral rotator muscles in a strengthening quadriceps exercise rehabilitation programme for patients with the patellofemoral pain syndrome. Design: Randomized controlled pilot trial. Setting: Clinical setting with home programme. Participants: Fourteen patients with patellofemoral pain syndrome. Intervention: The subjects were randomly assigned to the intervention group (strengthening of quadriceps plus strengthening of hip abductor and lateral rotator muscles) or to the control group (strengthening of quadriceps). Both groups participated in a six-week home exercise protocol. Main outcome measures: The perceived pain symptoms, isokinetic eccentric knee extensor, hip abductor and lateral rotator torques and the gluteus medius electromyographic activity were assessed before and after treatment. Parametric and non-parametric tests were used to compare the groups before and after treatment with α=0.05. Results: Only the intervention group improved perceived pain symptoms during functional activities (P=0.02—0.04) and also increased their gluteus medius electromyographic activity during isometric voluntary contraction (P=0.03). Eccentric knee extensors torque increased in both groups (P=0.04 and P=0.02). There was no statistically significant difference in the hip muscles torque in either group. Conclusion: Supplementation of strengthening of hip abductor and lateral rotator muscles in a strengthening quadriceps exercise programme provided additional benefits with respect to the perceived pain symptoms during functional activities in patients with patellofemoral pain syndrome after six weeks of treatment.

Trunk, Pelvis, Hip, and Knee Kinematics, Hip Strength, and Gluteal Muscle Activation During a Single-Leg Squat in Males and Females With and Without Patellofemoral Pain Syndrome

STUDY DESIGN Controlled laboratory study using a cross-sectional design. OBJECTIVES To determine whether there are any differences between the sexes in trunk, pelvis, hip, and knee kinematics, hip strength, and gluteal muscle activation during the performance of a single-leg squat in individuals with patellofemoral pain syndrome (PFPS) and control participants. BACKGROUND Though there is a greater incidence of PFPS in females, PFPS is also quite common in males. Trunk kinematics may affect hip and knee function; however, there is a lack of studies of the influence of the trunk in individuals with PFPS. METHODS Eighty subjects were distributed into 4 groups: females with PFPS, female controls, males with PFPS, and male controls. Trunk, pelvis, hip, and knee kinematics and gluteal muscle activation were evaluated during a single-leg squat. Hip abduction and external rotation eccentric strength was measured on an isokinetic dynamometer. Group differences were assessed using a 2-way multivariate analysis of variance (sex by PFPS status). RESULTS Compared to controls, subjects with PFPS had greater ipsilateral trunk lean (mean ± SD, 9.3° ± 5.3° versus 6.7° ± 3.0°; P = .012), contralateral pelvic drop (10.3° ± 4.7° versus 7.4° ± 3.8°; P = .003), hip adduction (14.8° ± 7.8° versus 10.8° ± 5.6°; P<.0001), and knee abduction (9.2° ± 5.0° versus 5.8° ± 3.4°; P<.0001) when performing a single-leg squat. Subjects with PFPS also had 18% less hip abduction and 17% less hip external rotation strength. Compared to female controls, females with PFPS had more hip internal rotation (P<.05) and less muscle activation of the gluteus medius (P = .017) during the single-leg squat. CONCLUSION Despite many similarities in findings for males and females with PFPS, there may be specific sex differences that warrant consideration in future studies and when clinically evaluating and treating females with PFPS.

Eccentric Hip Muscle Function in Females With and Without Patellofemoral Pain Syndrome

CONTEXT Patellofemoral pain syndrome (PFPS) is a common knee condition in athletes. Recently, researchers have indicated that factors proximal to the knee, including hip muscle weakness and motor control impairment, contribute to the development of PFPS. However, no investigators have evaluated eccentric hip muscle function in people with PFPS. OBJECTIVE To compare the eccentric hip muscle function between females with PFPS and a female control group. DESIGN Cross-sectional study. SETTING Musculoskeletal laboratory. PATIENTS OR OTHER PARTICIPANTS two groups of females were studied: a group with PFPS (n = 10) and a group with no history of lower extremity injury or surgery (n = 10). INTERVENTION(S) Eccentric torque of the hip musculature was evaluated on an isokinetic dynamometer. MAIN OUTCOME MEASURE(S) Eccentric hip abduction, adduction, and external and internal rotation peak torque were measured and expressed as a percentage of body mass (Nm/kg x 100). We also evaluated eccentric hip adduction to abduction and internal to external rotation torque ratios. The peak torque value of 5 maximal eccentric contractions was used for calculation. Two-tailed, independent-samples t tests were used to compare torque results between groups. RESULTS Participants with PFPS exhibited much lower eccentric hip abduction (t(18) = -2.917, P = .008) and adduction (t(18) = -2.764, P = .009) peak torque values than did their healthy counterparts. No differences in eccentric hip external (t(18) = 0.45, P = .96) or internal (t(18) = -0.742, P = .47) rotation peak torque values were detected between the groups. The eccentric hip adduction to abduction torque ratio was much higher in the PFPS group than in the control group (t(18) = 2.113, P = .04), but we found no difference in the eccentric hip internal to external rotation torque ratios between the 2 groups (t(18) = -0.932, P = .36). CONCLUSIONS Participants with PFPS demonstrated lower eccentric hip abduction and adduction peak torque and higher eccentric adduction to abduction torque ratios when compared with control participants. Thus, clinicians should consider eccentric hip abduction strengthening exercises when developing rehabilitation programs for females with PFPS.

Frontal Plane Biomechanics in Males and Females with and without Patellofemoral Pain

PURPOSE The studys purpose was to compare trunk, pelvis, hip, and knee frontal plane biomechanics in males and females with and without patellofemoral pain syndrome (PFPS) during stepping. METHODS Eighty recreational athletes were equally divided into four groups: female PFPS, female controls, male PFPS, and male controls. Trunk, pelvis, hip, and knee frontal plane kinematics and activation of the gluteus medius were evaluated at 15°, 30°, 45°, and 60° of knee flexion during the downward and upward phases of the stepping task. Isometric hip abductor torque was also evaluated. RESULTS Females showed increased hip adduction and knee abduction at all knee flexion angles, greater ipsilateral trunk lean and contralateral pelvic drop from 60° of knee flexion till the end of the stepping task (P = 0.027-0.001), diminished hip abductor torque (P < 0.001), and increased gluteus medius activation than males (P = 0.008-0.001). PFPS subjects presented increased knee abduction at all the angles evaluated; greater trunk, pelvis, and hip motion from 45° of knee flexion of the downward phase till the end of the maneuver; and diminished gluteus medius activation at 60° of knee flexion, compared with controls (P = 0.034-0.001). Females with PFPS showed lower hip abductor torque compared with the other groups. CONCLUSIONS Females presented with altered frontal plane biomechanics that may predispose them to knee injury. PFPS subjects showed frontal plane biomechanics that could increase the lateral patellofemoral joint stress at all the angles evaluated and could increase even more from 45° of knee flexion in the downward phase until the end of the maneuver. Hip abductor strengthening and motor control training should be considered when treating females with PFPS.

Hip and knee kinematics are associated with pain and self-reported functional status in males and females with patellofemoral pain.

Altered hip and knee kinematics in the frontal and transverse planes may increase patellofemoral joint stress and contribute to the development of patellofemoral pain. The purpose of this cross-sectional study was to evaluate the association among hip and knee kinematics, pain, and self-reported functional status in males and females with patellofemoral pain. 20 males and 20 females with patellofemoral pain participated in this study. 3-dimensional hip and knee kinematics were quantified while performing a step-down task. A visual analogue scale was used to evaluate usual knee pain. The anterior knee pain scale was used to evaluate the knee functional score. For both groups combined, greater usual pain was associated with greater peak hip adduction, hip internal rotation and knee abduction (r=0.54-0.57, P<0.001). Also, modest to low correlations (r=-0.48 to - 0.37, P=0.03-0.08) were found among hip and knee kinematics and functional score. Stepwise regression revealed that peak hip internal rotation and hip adduction were significant predictors of pain, while peak hip adduction was the only predictor of function. Greater hip adduction, hip internal rotation and knee abduction are associated with higher levels of pain and reduced function in males and females with patellofemoral pain.

Conjunto mínimo de parâmetros para avaliação da microbiota do solo e da fixação biológica do nitrogênio pela soja

The objective of this work was to evaluate and validate a minimum set of parameters capable of monitoring, under field conditions, soil microbes and/or the biological N2 fixation process with the soybean crop. The field trials were performed in commercial fields (2002/2003) and experimental areas (2004/2004), with complete randomized blocks design. Microbial biomass C (MBC) and N (MBN) were adequate for the quantitative evaluation of soil microbes; the parameters were significantly correlated therefore the determination of only one of them is sufficient. Positive and significant correlations were also obtained between the parameters of shoot dry weight (SDW) and MBC and MBN. The analysis of total soil DNA by the denaturating gradient gel electrophoresis method (DGGE) detected qualitative changes in soil microbes, related to the homogeneity of the area, as well as to differences among treatments, areas and harvests. Nodule dry weight (NDW) was the most suitable parameter for the evaluation of nodulation. Significant correlations were obtained between the SDW and the total N accumulated in shoots (TNS). Similar results were obtained between SDW and total N-ureides (TNU). Monitoring of the symbiosis in soils traditionally cropped with soybean and poor on N may be achieved only by the determination of NDW and SDW.

Relative entropy measures applied to healthy and pathological voice characterization

Abstract Nowadays, noninvasive methods of diagnosis have increased due to demands of the population that requires fast, simple and painless exams. These methods have become possible because of the growth of technology that provides the necessary means of collecting and processing signals. New methods of analysis have been developed to understand the complexity of voice signals, such as nonlinear dynamics aiming at the exploration of voice signals dynamic nature. The purpose of this paper is to characterize healthy and pathological voice signals with the aid of relative entropy measures. Phase space reconstruction technique is also used as a way to select interesting regions of the signals. Three groups of samples were used, one from healthy individuals and the other two from people with nodule in the vocal fold and Reinke’s edema. All of them are recordings of sustained vowel /a/ from Brazilian Portuguese. The paper shows that nonlinear dynamical methods seem to be a suitable technique for voice signal analysis, due to the chaotic component of the human voice. Relative entropy is well suited due to its sensibility to uncertainties, since the pathologies are characterized by an increase in the signal complexity and unpredictability. The results showed that the pathological groups had higher entropy values in accordance with other vocal acoustic parameters presented. This suggests that these techniques may improve and complement the recent voice analysis methods available for clinicians.

A neural-wavelet architecture for voice conversion

In this letter we propose a new architecture for voice conversion that is based on a joint neural-wavelet approach. We also examine the characteristics of many wavelet families and determine the one that best matches the requirements of the proposed system. The conclusions presented in theory are confirmed in practice with utterances extracted from TIMIT speech corpus.

Predictability analysis of voice signals

This paper, proposes a method of voice signal analysis based on predictability measures. The objective is the differentiation of three groups of signals: healthy, nodules on the vocal folds, and Reinkes edema. This method is a slight reformulation of a measure called predictive power (PP) that uses the relative entropy between the signal and its prediction error to capture information about the predictability of the patients voice production system. A wavelet decomposition model provides the predictions. The results obtained for the healthy group were substantially higher than those of the pathologic groups. This decrease of predictability may be interpreted as an indication of the increase of intricacy and irregularity associated with the studied larynx pathologies.

Efficient methods for learning Bayesian network super-structures

Learning large Bayesian networks (BN) from data is a challenging problem due to the vastness of the structure space. An effective way to turn this problem affordable is the use of super-structures-SS (undirected graphs that contain the BN skeleton). However, the literature has been lacking of specialized methods for estimating SS. We present here two algorithms intended for such purpose in the hybrid approach of BN structure learning. The first one, called Opt01SS, learns SS using only zero-and-first-order conditional independence (CI) tests in a way that allows dealing with the presence of approximate-deterministic relationships and inconsistent CIs, commonly found in small samples. The second algorithm, called OptHPC, is a computational optimized version of the recent HPC algorithm (De Morais and Aussem 2010, [17]) that showed an attractive accuracy for SS recovery. Results on various benchmark networks showed that the proposed algorithms achieve a balance between sensitivity and specificity clearly more favorable for the task of SS estimation than several representative state-of-the-art methods. The computational cost was also found to be reasonable, being Opt01SS one of the most competitive among the analyzed algorithms.