Correlations between physical activity and quality of life in entrepreneurs from Wrocław, Poland

BACKGROUND

Limited physical activity is one of the main reasons for the rapid increase in the prevalence of diseases of affluence, which can lead to premature deaths in adults. Quality of life may be one of potential determinants of physical activity. The aim of this article is to identify the relationships between physical activity and quality of life in entrepreneurs from Wroclaw, Poland.

METHODS

A cross-sectional study was conducted on a group of 616 entrepreneurs (216 women and 400 men). A diagnostic survey method was used with a direct interview technique. The research tools included the International Physical Activity Questionnaire Short Form and the World Health Organization Quality of Life Questionnaire.

RESULTS

Among the studied entrepreneurs, along with their higher ratings of overall quality of life, the odds of high rather than low levels of physical activity increased nearly fivefold (OR 4.86, CI 3.34-7.07). Entrepreneurs with higher assessment levels of their perceived health condition were nearly twice as likely to report high rather than low physical activity levels (OR 1.92, CI 1.42-2.59). The conditional probability of high rather than low levels of physical activity also increased in the entrepreneurs with higher assessments of quality of life in the physical, psychological, social, and environmental domains, by 34%, 11%, 5%, and 6%, respectively.

CONCLUSION

Programs promoting physical activity among entrepreneurs, which focus on moderate and high intensity exercise, should be considered desirable in the context of the study findings. Activities aimed at improving quality of life in the physical and psychological domains as a potential determinant of the level of physical activity of entrepreneurs are also worth recommending.

Repeatability of the Vibroarthrogram in the Temporomandibular Joints

Current research concerning the repeatability of the joint's sounds examination in the temporomandibular joints (TMJ) is inconclusive; thus, the aim of this study was to investigate the repeatability of the specific features of the vibroarthrogram (VAG) in the TMJ using accelerometers. The joint sounds of both TMJs were measured with VAG accelerometers in two groups, study and control, each consisting of 47 participants (n = 94). Two VAG recording sessions consisted of 10 jaw open/close cycles guided by a metronome. The intraclass correlation coefficient (ICC) was calculated for seven VAG signal features. Additionally, a k-nearest-neighbors (KNN) classifier was defined and compared with a state-of-the-art method (joint vibration analysis (JVA) decision tree). ICC indicated excellent (for the integral below 300 Hz feature), good (total integral, integral above 300 Hz, and median frequency features), moderate (integral below to integral above 300 Hz ratio feature) and poor (peak amplitude feature) reliability. The accuracy scores for the KNN classifier (up to 0.81) were higher than those for the JVA decision tree (up to 0.60). The results of this study could open up a new field of research focused on the features of the vibroarthrogram in the context of the TMJ, further improving the diagnosing process.

Using Nonlinear Vibroartrographic Parameters for Age-Related Changes Assessment in Knee Arthrokinematics

Changes in articular surfaces can be associated with the aging process and as such may lead to quantitative and qualitative impairment of joint motion. This study is aiming to evaluate the age-related quality of the knee joint arthrokinematic motion using nonlinear parameters of the vibroarthrographic (VAG) signal. To analyse the age-related quality of the patellofemoral joint (PFJ), motion vibroarthrography was used. The data that were subject to analysis represent 220 participants divided into five age groups. The VAG signals were acquired during flexion/extension knee motion and described with the following nonlinear parameters: recurrence rate (RR) and multi-scale entropy (MSE). RR and MSE decrease almost in a linear way with age (main effects of group p<0.001; means (SD): RR=0.101(0.057)−0.020(0.017); and MSE=20.9(8.56)−13.6(6.24)). The RR post-hoc analysis showed that there were statistically significant differences (p<0.01) in all comparisons with the exception of the 5th−6th life decade. For MSE, statistically significant differences (p<0.01) occurred for: 3rd−7th, 4th−7th, 5th−7th and 6th life decades. Our results imply that degenerative age-related changes are associated with lower repeatability, greater heterogeneity in state space dynamics, and greater regularity in the time domain of VAG signal. In comparison with linear VAG measures, our results provide additional information about the nature of changes of the vibration dynamics of PFJ motion with age.

Effects of Viscosupplementation on Quality of Knee Joint Arthrokinematic Motion Analyzed by Vibroarthrography

OBJECTIVE

To evaluate the influence of viscosupplementation on osteoarthritic knee arthrokinematics analyzed by VAG. It is considered that intra-articular hyaluronic acid injection may improve the function of synovial joints by recovery of friction-reducing properties of articular environment.

DESIGN

Thirty-five patients with knee osteoarthritis (grade II according to the Kellgren-Lawrence system) and 50 asymptomatic subjects were enrolled in the study. Patients were analyzed at 3 time points: 1 day before and 2 weeks and 4 weeks after single injection of 1.5% cross-linked hyaluronate. Control subjects were tested once. The vibroarthrographic signals were collected during knee flexion/extension motion using an accelerator and described by variation of mean square (VMS), mean range (R5), and power spectral density for frequency of 50 to 250 Hz (P1), and 250 to 450 Hz (P2).

RESULTS

Patients before viscosupplementation were characterized by about 2-fold higher values of vibroarthrographic parameters than controls. Two weeks after the procedure, the values of R5, P1, and P2 significantly decreased, in comparison to pre-injection. At 4 weeks post-injection, we noted a significant increase in R5, P1, and P2 values, when compared to 2 weeks post-injection. Finally, at 4 weeks post-injection, the level of VMS, R5, and P2 parameters did not differ from values obtained at pre-injection.

CONCLUSIONS

We showed that viscosupplementation may be effective in providing arthrokinematics improvement, but with a relatively short period of duration. This phenomenon is observed as decreased vibroacoustic emission, which reflects a more smooth movement in the joint.

Muscle activation time and free-throw effectiveness in basketball

This study attempts to analyze the relationship between free-throw efficiency and the time of arm muscle activation in players from 3 basketball teams with different levels of experience was investigated. During the experiment each player made 20 free throws during which the activation time of his right and left biceps and triceps brachii muscles were measured with the use of surface electromyography and high-speed cameras. Significant differences in muscle activation time (t) during a free throw were found between the groups of basketball players (p = 0.038) (novices: t = 0.664 ± 0.225 s, intermediate-level players: t = 1.15 ± 0.146 s, experts: t = 1.01 ± 0.388 s). In the right triceps brachii muscle in expert basketball players the coefficient of variation (CV) amounted to 44.60% at 81% efficiency, and in novices to 27.12% at 53% efficiency. The time of arm muscle activation during a free throw and its fluctuations vary along with the training experience of basketball players. In all studied groups of players, the variability of muscle activation time in accurate free throws is greater than in inaccurate free throws. Free-throw speed is irrelevant for free-throw efficiency.

Caffeine-Induced Effects on Human Skeletal Muscle Contraction Time and Maximal Displacement Measured by Tensiomyography

Studies on muscle activation time in sport after caffeine supplementation confirmed the effectiveness of caffeine. The novel approach was to determine whether a dose of 9 mg/kg/ body mass (b.m.) of caffeine affects the changes of contraction time and the displacement of electrically stimulated muscle (gastrocnemius medialis) in professional athletes who regularly consume products rich in caffeine and do not comply with the caffeine discontinuation period requirements. The study included 40 professional male handball players (age = 23.13 ± 3.51, b.m. = 93.51 ± 15.70 kg, height 191 ± 7.72, BMI = 25.89 ± 3.10). The analysis showed that in the experimental group the values of examined parameters were significantly reduced (p ≤ 0.001) (contraction time: before = 20.60 ± 2.58 ms/ after = 18.43 ± 3.05 ms; maximal displacement: before = 2.32 ± 0.80 mm/after = 1.69 ± 0.51 mm). No significant changes were found in the placebo group. The main achievement of this research was to demonstrate that caffeine at a dose of 9 mg/kg in professional athletes who regularly consume products rich in caffeine has a direct positive effect on the mechanical activity of skeletal muscle stimulated by an electric pulse.

Vibroarthrographic Signal Spectral Features in 5-Class Knee Joint Classification

Vibroarthrography (VAG) is a non-invasive and potentially widely available method supporting the joint diagnosis process. This research was conducted using VAG signals classified to five different condition classes: three stages of chondromalacia patellae, osteoarthritis, and control group (healthy knee joint). Ten new spectral features were proposed, distinguishing not only neighboring classes, but every class combination. Additionally, Frequency Range Maps were proposed as the frequency feature extraction visualization method. The results were compared to state-of-the-art frequency features using the Bhattacharyya coefficient and the set of ten different classification algorithms. All methods evaluating proposed features indicated the superiority of the new features compared to the state-of-the-art. In terms of Bhattacharyya coefficient, newly proposed features proved to be over 25% better, and the classification accuracy was on average 9% better.

Vibroarthrographic analysis of patellofemoral joint arthrokinematics during squats with increasing external loads

Background

The patellofemoral joint (PFJ) provides extremely low kinetic friction, which results in optimal arthrokinematic motion quality. Previous research showed that these friction-reducing properties may be diminished due to the increase in articular contact forces. However, this phenomenon has not been analyzed in vivo during functional daily-living activities. The aim of this study was the vibroarthrographic assessment of changes in PFJ arthrokinematics during squats with variated loads.

Methods

114 knees from 57 asymptomatic subjects (23 females and 34 males) whose ages ranged from 19 to 26 years were enrolled in this study. Participants were asked to perform 3 trials: 4 repetitions of bodyweight squats (L0), 4 repetitions of 10 kg barbell back loaded squats (L10), 4 repetitions of 20 kg barbell back loaded squats (L20). During the unloaded and loaded (L10, L20) squats, vibroarthrographic signals were collected using an accelerometer placed on the patella and were described by the following parameters: variation of mean square (VMS), mean range (R4), and power spectral density for frequency of 50–250 Hz (P1) and 250–450 Hz (P2).

Results

Obtained results showed that the lowest values were noted in the unloaded condition and that the increased applied loads had a significant concomitant increase in all the aforementioned parameters bilaterally (p < 0.05).

Conclusion

This phenomenon indicates that the application of increasing knee loads during squats corresponds to higher intensity of vibroacoustic emission, which might be related to higher contact stress and kinetic friction as well as diminished arthrokinematic motion quality.

Subjective and Objective Evaluation of the Functional Condition after a Single Lateral Sprain of the Ankle in Athletes

BACKGROUND

Ankle sprains can lead to functional deficits. However, few papers have investigated deficits following a single lateral ankle sprain as either assessed subjectively by the patient (e.g., with questionnaires) or measured objectively (e.g., by evaluation of postural stability). This paper aims to provide subjective and objective assessment of functional status in athletes after a single lateral ankle sprain.

MATERIAL AND METHODS

A lateral ankle sprain group (LAS) consisted of 20 athletes after a single lateral ankle sprain (mean age 23 ± 1.78 years). A control group (CTRL) comprised 20 athletes with no history of injury (mean age 22.5 ± 2.67 years). Subjective assessment was based on the Foot and Ankle Disability Index questionnaire (FADI-Q). A Biodex Balance System SD dynamic platform was used to assess postural stability. Static and dynamic testing was performed in single-leg stance.

RESULTS

Statistically significant differences were noted during the comparison of the LAS and CTRL groups in FADI-Q in the following parts: FADI (p=0,017) and FADI TOTAL (p=0,049). Moreover, statistically significant differences were noted in the LAS group between subjects with instability (N-STAB) and without instability (STAB) of the ankle in the parts FADI (p=0,006), FADI SPORT (p=0,011) and FADI TOTAL (p=0,002). During static and dynamic postural stability testing, no significant differences were found between sprained and healthy limbs, between the LAS and CTRL groups, or between the STAB and N-STAB groups.

CONCLUSIONS

1. Athletes after ankle sprain assessed their functio-nal status as worse compared to the control group. Moreover, deterioration in functional status was perceived by athletes with an unstable ankle joint compared to participants with a stable ankle joint. 2. The study indicates that a single ankle sprain is associated with a high risk of developing functio-nal instability. 3. The process of maintaining postural stability was similar in athletes after a single ankle sprain and in those without a history of ankle injury.

Effects of Viscosupplementation on Knee Joint Arthrokinematics - Pilot Study

BACKGROUND

Osteoarthritis is one of the most common dysfunctions of the musculoskeletal system and viscosup-plementation is becoming an increasingly popular treatment in OA. However, current knowledge regarding biomechanical changes in synovial joints reveals many discrepancies. Therefore, the aim of our study was to evaluate the effect of visco-supplementation on knee joint arthrokinematics as analyzed by vibroarthrography.

MATERIAL AND METHODS

Seventeen individuals diagnosed with moderate knee osteoarthritis (VSC) were examined before and after a single injection of hyaluronate. A control group consisted of 30 asymptomatic individuals. During alter-nating extension/flexion of the knee joint, a 6-second vibroarthrographic signal was recorded using an accelerometer. The following parameters were calculated: variance (VMS), amplitude (R4), and spectral power density in the 50-250 Hz (P1) and 250-450 Hz (P2) bands.

RESULTS

Statistical analysis showed significant differences (p&lt;0.05) in the values of R4 and P2, which were higher in the VSC group than among the controls. After viscosupplementation, the values of R4, P1 and P2 in the VSC group de-creased to a level not significantly different from that seen among the controls.

CONCLUSIONS

1. After a single intra-articular HA injection, joint motion-related vibrations were reduced, which was recorded as a decreased intensity of vibroacoustic emission. 2. This suggests that the use of viscosupplementation in pa-tients with moderate knee osteoarthritis may improve qualitative aspects of arthrokinematics.

Gait and functional status analysis before and after total knee arthroplasty

BACKGROUND

Among the procedures for severe gonarthrosis, total knee arthroplasty (TKA) is considered a successful method patient satisfaction and functional improvement; however, TKA is commonly associated with incompletely recovered gait function. The aim of this study was to evaluate the influence of TKA and physiotherapy programmes on gait features and patient-reported functional status and the relationship between them, leading to broader knowledge of the origins of long-term gait disturbances.

METHODS

Walking speed, step length and single support time were analysed by GAITRite system in 60 healthy controls and 21 TKA patients analysed at four time points: one day before and five days after surgery and before and after a three-week rehabilitation (12 and 15 weeks after surgery). Functional status was assessed using the Western Ontario and McMaster Osteoarthritis Index (WOMAC).

RESULTS

At all time points, the TKA subjects walked significantly slower than the controls, but walking speed continuously increased after surgery. Gait asymmetries were observed in single support time (before surgery) and step length (after surgery). Partial restoration of gait function was observed 12 weeks after surgery and completion of the rehabilitation programme. An indirect correlation between gait velocity and function WOMAC subscores was found.

CONCLUSIONS

Patients after TKA were characterised by significant improvements in self-reported functionality and progressive reduction of gait abnormalities, probably related to pain reduction. However, at 15 weeks after surgery, patients exhibited step length asymmetry, which could be considered as an effect of habits of three-point crutch gait in the early postoperative period.

Age-related changes in shock absorption capacity of the human spinal column

Background

The spinal column possesses shock absorption properties, mainly provided by the intervertebral discs. However, with the process of senescence, all structures of the spine, including the discs, undergo degenerative changes. It may lead to alteration of the mechanical properties of the spinal motion segment and diminished capacity for vibration attenuation.

Objective

The objective of this study was to investigate the age-related changes in shock absorption properties of the spine.

Patients and methods

A total of 112 individuals divided into three groups according to age (third, fifth, and seventh decades of life) were enrolled in this study. The transmissibility of vibrations through the spine was measured in a standing position on a vibration platform by accelerometers mounted at the levels of S2 and C0. Registered signals were described using four parameters: VMS (variability), peak-to-peak amplitude (PPA), and spectral activity in two bands F2 (0.7–5 Hz) and F20 (15–25 Hz).

Results

In all age groups, signals registered at C0 were characterized by significantly lower values of VMS, PPA, and F20, when compared to level S2. Simultaneously, the parameter F20 significantly differed among all age groups when C0 vibrations were analyzed: 2.43±1.93, 5.02±3.61, and 10.84±5.12 for the third, fifth, and seventh decades of life, respectively.

Conclusion

The human spinal column provides vibration attenuation; however, this property gradually declines with the aging process.

Analysis and multiclass classification of pathological knee joints using vibroarthrographic signals

BACKGROUND AND OBJECTIVE

Vibroarthrography (VAG) is a method developed for sensitive and objective assessment of articular function. Although the VAG method is still in development, it shows high accuracy, sensitivity and specificity when comparing results obtained from controls and the non-specific, knee-related disorder group. However, the multiclass classification remains practically unknown. Therefore the aim of this study was to extend the VAG method classification to 5 classes, according to different disorders of the patellofemoral joint.

METHODS

We assessed 121 knees of patients (95 knees with grade I-III chondromalacia patellae, 26 with osteoarthritis) and 66 knees from 33 healthy controls. The vibroarthrographic signals were collected during knee flexion/extension motion using an acceleration sensor. The genetic search algorithm was chosen to select the most relevant features of the VAG signal for classification. Four different algorithms were used for classification of selected features: logistic regression with automatic attribute selection (SimpleLogistic in Weka), multilayer perceptron with sigmoid activation function (MultilayerPerceptron), John Platt's sequential minimal optimization algorithm implementation of support vector classifier (SMO) and random forest tree (RandomForest). The generalization error of classification algorithms was evaluated by stratified 10-fold cross-validation.

RESULTS

We obtained levels of accuracy and AUC metrics over 90%, more than 93% sensitivity and more than 84% specificity for the logistic regression-based method (SimpleLogistic) for a 2-class classification. For the 5-class method, we obtained 69% and 90% accuracy and AUC respectively, and sensitivity and specificity over 91% and 69%.

CONCLUSIONS

The results of this study confirm the high usefulness of quantitative analysis of VAG signals based on classification techniques into normal and pathological knees and as a promising tool in classifying signals of various knee joint disorders and their stages.

Joint Motion Quality in Chondromalacia Progression Assessed by Vibroacoustic Signal Analysis

BACKGROUND

Because of the specific biomechanical environment of the patellofemoral joint, chondral disorders, including chondromalacia, often are observed in this articulation. Chondromalacia via pathologic changes in cartilage may lead to qualitative impairment of knee joint motion.

OBJECTIVE

To determine the patellofemoral joint motion quality in particular chondromalacia stages and to compare with controls.

DESIGN

Retrospective, comparative study.

SETTING

Voivodship hospitals, university biomechanical laboratory.

PATIENTS

A total of 89 knees with chondromalacia (25 with stage I; 30 with stage II and 34 with stage III) from 50 patients and 64 control healthy knees (from 32 individuals).

METHODS

Vibroacoustic signal pattern analysis of joint motion quality.

MAIN OUTCOME MEASUREMENTS

For all knees vibroacoustic signals were recorded. Each obtained signal was described by variation of mean square, mean range (R4), and power spectral density for frequency of 50-250 Hz (P1) and 250-450 Hz (P2) parameters.

RESULTS

Differences between healthy controls and all chondromalacic knees as well as chondromalacia patellae groups were observed as an increase of analyzed parameters (P < .001) with only one exception. No statistically significant difference between control group and stage I of chondromalacia patellae was found. All chondromalacia groups were differentiated by the use of all analyzed parameters (P < .01), whose values correspond to the progress of chondromalacia.

CONCLUSIONS

Chondromalacia generates abnormal vibroacoustic signals, and there seems to be a relationship between the level of signal amplitude as well as frequency and cartilage destruction from the superficial layer to the subchondral bone.

LEVEL OF EVIDENCE

IV.

Joint motion quality in vibroacoustic signal analysis for patients with patellofemoral joint disorders

BACKGROUND

Chondromalacia, lateral patellar compression syndrome and osteoarthritis are common patellofemoral joint disorders leading to functional and/or structural disturbances in articular surfaces. The objective of the study was to evaluate their impact on joint motion quality via the vibroacoustic signal generated during joint movement analysis.

METHODS

Seventy-three patients (30 with chondromalacia, 21 with lateral patellar compression syndrome, and 22 with osteoarthritis) and 32 healthy controls were tested during flexion/extension knee motion for vibroacoustic signals using an acceleration sensor. Estimated parameters: variation of mean square (VMS), difference between mean of four maximum and mean of four minimum values (R4), power spectral density for frequency of 50-250 Hz (P1) and 250-450 Hz (P2) were analyzed.

RESULTS

Vibroacoustic signals recorded for particular disorders were characterized by significantly higher values of parameters in comparison to the control group. Moreover, differences were found among the various types of patellofemoral joint disturbances. Chondromalacia and osteoarthritis groups showed differences in all parameters examined. In addition, osteoarthritis patients exhibited differences in VMS, P1 and P2 values in comparison to lateral patellar compression syndrome patients. However, only the value of R4 was found to differ between knees with lateral patellar compression syndrome and those with chondromalacia.

CONCLUSION

Our results suggest that particular disorders are characterized by specific vibroacoustic patterns of waveforms as well as values of analyzed parameters.

Vibroarthrography in the evaluation of musculoskeletal system - a pilot study

BACKGROUND. Disorders of the articular surfaces are associated with impaired quality of joint motion and joint play. Crepitations are the hallmark clinical sign. This paper aims to present the possibilities of using vibroacoustic signal analysis in assessing the function of articular surfaces in the course of disorders of the knee and shoulder. MATERIAL AND METHODS. The study involved 30 people, 10 for each of the following disorders: patellar chondromalacia (Ch), meniscal tears (Mc), and degenerative changes of the glenohumeral joint (GH). A control group (K1-K3) was matched to each dysfunctional group. 6-second vibroacoustic signals (VAG) were recorded during motion in particular joints. The resulting time series were filtered (50-1000 Hz) and the following parameters were calculated: variance-mean-square (VMS), the mean of the four lowest and four highest values (R4) and the total spectral power density in the 50-250 Hz (P1) and 250-450 Hz (P2) ranges. RESULTS. Depending on the type of disorder, VAG signals in the dysfunctional groups were characterized by higher variability, amplitude and frequency than was the case in the control groups. This is reflected in the values of all parameters (VMS, R4, P1, P2), which were significantly higher in the Ch, Mc and GH groups compared to K1-K3. CONCLUSIONS. 1. Vibroarthrography can be a useful tool for accurate and objective assessment of the quality of joint motion. 2. The non-invasive nature of vibroarthrography allows the use of this method to monitor the effects of the treatment of joint structures.

Assessment of neuromuscular control in patients after anterior cruciate ligament reconstruction

BACKGROUND

The anterior cruciate ligament (ACL) is one of the most important stabilisers of the knee joint. The key role of ACL is to resist anterior translation of the tibia in relation to the femur. At the same time, ACL does not only perform a mechanical limiting function, but is also an important component of the sensorimotor system. The aim of this study was to assess neuromuscular control in patients after ACL reconstruction by evaluatingthe maintenance of dynamic balance.

MATERIAL AND METHODS

Twenty-six patients (aged 28.4±6.3 years) after ACL reconstruction (ACLR group) were enrolled. All patients had undergone arthroscopic reconstruction of ACL, and were recruited to the study 11-13 months after the surgery. Thirty-seven healthy individuals served as a control group (CTRL). The maintenance of the single-leg and two-leg standing position on an unstable surface was assessed using the Biodex Balance System SD.

RESULTS

The ACLR group differed from the control group in the values of the overall stability index (p<0.05; 6.53±2.04, and 5.27±1.42, respectively) when stability control in the two-leg position was assessed. Additionally, in the single-leg position, the values of the study parameters were significantly higher (p<0.05) in ACLR in comparison to CTRL: 9.73±2.55 vs.7.23±1.48, and 9.42±2.38 vs. 5.64±1.51 respectively, for the dominant and non-dominant leg.

CONCLUSIONS

At one year after ACL reconstruction, significant deficits of neuromuscular control were observed during motor tasks requiring considerable sensorimotor system involvement.