Modified three-layer vesicourethral reconstruction in robot-assisted radical prostatectomy can change cystography pattern and improve early recovery of continence.

BACKGROUND AND OBJECTIVES: To determine early continence outcomes after three-layer vesicourethral reconstruction during robot-assisted radical prostatectomy (RARP) and the role of postoperative cystography pattern. METHODS: Between May 2015 and January 2019, a total of 170 consecutive patients with localized prostate cancer who underwent RARP, were divided into one- and three-layer groups based on the method of vesicourethral reconstruction. Continent status, preoperative, intraoperative, postoperative, clinicopathological variables, and cystography parameters were analyzed. The patients were followed up for at least 12 months. RESULTS: Of the 170 consecutive patients, 85 with one-layer vesicourethral anastomosis, and 85 with three-layer reconstruction. The continence rates immediately after catheter removal, 4, 12, and 24 weeks after RARP were 47.1%, 75.3%, 92.9%, and 98.8% in the three-layer group; compared to 15.3%, 60%, 78.8%, and 90.6% in the one-layer group, respectively. In the multivariate analysis, three-layer reconstruction was the only independent variable with a 42% risk reduction of postprostatectomy incontinence (hazard ratio (HR): 0.58, 95% confidence interval (CI) = 0.42-0.80, p = 0.001). Cystography in the three-layer group revealed less anastomotic leakage, less sharp bladder neck angle, and higher bladder neck level category. CONCLUSIONS: Three-layer anatomical reconstruction demonstrated promising early continence outcomes, and postoperative cystography revealed a specific pattern more associated with continence.

Physical function as a predictor of chemotherapy-induced peripheral neuropathy in patients with pancreatic cancer.

BACKGROUND: A growing body of research indicates that poor functional status before chemotherapy may be correlated with the severity of chemotherapy-induced peripheral neuropathy (CIPN) after the neurotoxic treatment. However, little is known about the associations between pre-chemotherapy physical function and CIPN in patients with pancreatic cancer. PURPOSE: To identify the predictors of CIPN in relation to pre-chemotherapy physical function in patients with pancreatic cancer. METHODS: This secondary analysis included data from patients with pancreatic cancer who participated in a longitudinal research study at National Cheng Kung University Hospital, Tainan, Taiwan. Four physical function tests (i.e., grip strength, Timed Up and Go (TUG), 2-minute step test (2MST), and Romberg test) and two questionnaires (The European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 [EORTC QLQ-C30] and Chemotherapy-Induced Peripheral Neuropathy Module [CIPN20]) were assessed at baseline (i.e., before first chemotherapy session) and 2-, 3-, 4-, and 6-month follow-up. Multiple linear regression with adjustment for confounding factors was used to assess the associations between the four functional tests at baseline and the CIPN20 total score and individual subscale scores (sensory, motor, and autonomic) at 6-month follow-up. RESULTS: Data from a total of 209 pancreatic cancer patients (mean age: 64.4 years, 54.5% male) were analyzed. The findings showed that the severity of CIPN at 6-month follow-up was significantly associated with the baseline TUG completion time (ß = 0.684, p = 0.003). The TUG completion time was also positively correlated with the 6-month CIPN sensory and autonomic subscales. In addition, a baseline positive Romberg test (ß = 0.525, p = 0.009) was a significant predictor of the severity of motor neuropathy at 6-month follow-up. CONCLUSION: The TUG completion time and positive Romberg test before chemotherapy may be predictive factors of the CIPN severity 6 months after the commencement of chemotherapy. Accordingly, the incorporation of TUG and Romberg tests into the clinical assessment protocol emerges as imperative for individuals diagnosed with pancreatic carcinoma undergoing chemotherapy regimens.

Laterality in Body Coordination of Professional and Amateur Ballet Dancers While Performing a Single Pirouette with Pointe Shoes.

OBJECTIVE: Imbalances in muscle strength coordination owing to lateral preference may be a risk factor for injury in dancers. Postural control is essential for the basic turn in ballet (pirouette), owing to its lateral asymmetry. Since dance with pointe shoes demands greater range of motion, muscle strength, and balance control compared to dancing with flat shoes, pointe shoes may further add to the risk and cause an imbalance between the preferred and non-preferred legs during pirouette. In this study, we examined lateral differences in professional and experienced amateur ballet dancers during single pirouettes with pointe shoes to understand the multiple elements involved in lateral balance control in pirouettes. METHODS: Eight female professionals and seven female amateur ballet dancers performed single pirouettes in pointe shoes on both the preferred and non-preferred sides. To understand the body coordination laterality in single pirouettes, statistical parametric mapping was performed for the trunk, hip, knee, ankle angle, and center of mass-center of pressure inclination angle timeframe data during the pirouette in three phases: turn with double-leg (Phase 1), single-leg (Phase 2), and finish turning with a single-leg (Phase 3). In addition, the hop-up time was calculated as the percentage when the foot is not in contact with the ground in Phases 2 and 3. RESULTS: There were no lateral differences in trunk and lower limb angles in either group. Professional dancers showed slightly more inclination towards the stance leg during left rotation at the beginning of the movement (Phase 1) with longer hop-up time in Phase 2, whereas amateur dancers tended to tilt forward during the left turn (Phases 1 and 2) with longer hop-up time in Phase 3. CONCLUSION: It is notable that the COP-COM inclination angle was adjusted by hop-up and it caused the lateral differences in both professional and amateur dancers during a single pirouette with pointe shoes. This study highlights elements to consider in laterality when monitoring pirouette performance with pointe shoes.

Dancers with non-specific low back pain have less lumbar movement smoothness than healthy dancers.

BACKGROUND: Ballet is a highly technical and physically demanding dance form involving extensive end-range lumbar movements and emphasizing movement smoothness and gracefulness. A high prevalence of non-specific low back pain (LBP) is found in ballet dancers, which may lead to poor controlled movement and possible pain occurrence and reoccurrence. The power spectral entropy of time-series acceleration is a useful indicator of random uncertainty information, and a lower value indicates a greater smoothness or regularity. The current study thus applied a power spectral entropy method to analyze the movement smoothness in lumbar flexion and extension in healthy dancers and dancers with LBP, respectively. METHOD: A total of 40 female ballet dancers (23 in the LBP group and 17 in the control group) were recruited in the study. Repetitive end-range lumbar flexion and extension tasks were performed and the kinematic data were collected using a motion capture system. The power spectral entropy of the time-series acceleration of the lumbar movements was calculated in the anterior-posterior (AP), medial-lateral (ML), vertical (VT), and three-directional (3D) vectors. The entropy data were then used to conduct receiver operating characteristic curve analyses to evaluate the overall distinguishing performance and thus cutoff value, sensitivity, specificity, and area under the curve (AUC) were calculated. RESULTS: The power spectral entropy was significantly higher in the LBP group than the control group in the 3D vector in both lumbar flexion and lumber extension (flexion: p = 0.005; extension: p < 0.001). In lumbar extension, the AUC in the 3D vector was 0.807. In other words, the entropy provides an 80.7% probability of distinguishing between the two groups (i.e., LBP and control) correctly. The optimal cutoff entropy value was 0.5806 and yielded a sensitivity of 75% and specificity of 73.3%. In lumbar flexion, the AUC in the 3D vector was 0.777, and hence the entropy provided a probability of 77.7% of distinguishing between the two groups correctly. The optimal cutoff value was 0.5649 and yielded a sensitivity of 90% and a specificity of 73.3%. CONCLUSIONS: The LBP group showed significantly lower lumbar movement smoothness than the control group. The lumbar movement smoothness in the 3D vector had a high AUC and thus provided a high differentiating capacity between the two groups. It may therefore be potentially applied in clinical contexts to screen dancers with a high risk of LBP.

Application of Multiscale Sample Entropy in Assessing Effects of Exercise Training on Skin Blood Flow Oscillations in People with Spinal Cord Injury.

Spinal cord injury (SCI) causes a disruption of autonomic nervous regulation to the cardiovascular system, leading to various cardiovascular and microvascular diseases. Exercise training is an effective intervention for reducing risk for microvascular diseases in healthy people. However, the effectiveness of exercise training on improving microvascular function in people with SCI is largely unknown. The purpose of this study was to compare blood flow oscillations in people with spinal cord injury and different physical activity levels to determine if such a lifestyle might influence skin blood flow. A total of 37 participants were recruited for this study, including 12 athletes with SCI (ASCI), 9 participants with SCI and a sedentary lifestyle (SSCI), and 16 healthy able-bodied controls (AB). Sacral skin blood flow (SBF) in response to local heating at 42 °C for 50 min was measured using laser Doppler flowmetry. The degree of the regularity of blood flow oscillations (BFOs) was quantified using a multiscale entropy approach. The results showed that BFO was significantly more irregular in ASCI and AB compared to SSCI during the maximal vasodilation period. Our results also demonstrate that the difference in the regularity of BFOs between original SBF signal and phase-randomized surrogate time series was larger in ASCI and AB compared to SSCI. Our findings indicate that SCI causes a loss of complexity of BFOs and exercise training may improve complexity in people with SCI. This study demonstrates that multiscale entropy is a sensitive method for detecting differences between different categories of people with SCI and might be able to detect effects of exercise training related to skin blood flow.

Risk of major adverse cardiovascular events among second-line hormonal therapy for metastatic castration-resistant prostate cancer: A real-world evidence study.

BACKGROUND: To evaluate the possible major adverse cardiovascular events (MACE) associated with second-line hormonal therapy in patients with metastatic castration-resistant prostate cancer (mCRPC). METHODS: We performed a population-based real-world cohort study of 4962 prostate cancer patients between 2014 and 2017 utilizing the Chang Gung Research Database of Taiwan. The second-line hormonal therapies included enzalutamide and abiraterone acetate. The outcomes of interest were MACE, including acute coronary syndrome (ACS), ischemic stroke (IS), and heart failure (HF) events that resulted in hospitalization. Cox proportional-hazards models with inverse probability of treatment weighting (IPTW) with propensity scores were used. RESULTS: After IPTW, 288 patients were prescribed second-line hormonal therapy and 1575 received first-line androgen-deprivation therapy (ADT). Of all patients diagnosed with MACE, the event rates were 2.92% in the second-line hormonal group and 2.22% in the first-line ADT group. The mean follow-up period was 9.52 months for the second-line hormonal group. Patients who received second-line hormonal therapy exhibited a significantly increased risk for MACE (hazard ratio [HR]: 3.15; 95% confidence interval [CI]: 2.03-4.89), ACS (HR: 4.94; 95% CI: 2.36-10.33), and HF (HR: 2.83; 95% CI: 1.53-5.25), compared with the first-line ADT group, but a similar risk for IS was observed in both groups (HR: 1.70; 95% CI: 0.95-3.04). CONCLUSIONS: The real-world evidence study revealed increased risks for MACE in mCRPC patients receiving second-line hormonal therapy.

Magnetic Resonance Elastography in the Assessment of Acute Effects of Kinesio Taping on Lumbar Paraspinal Muscles.

BACKGROUND: Kinesio tape (KT) is an elastic therapeutic tape used for treating sports-related injuries and a number of other disorders. To date, the objective evidence to link pathophysiological effects and actual reactions triggered by KT is limited. PURPOSE: To explore the effect of KT on the lumbar paraspinal muscles by magnetic resonance (MR) elastography. STUDY TYPE: Prospective observational study. POPULATION: Sixty-six asymptomatic volunteers with 31 women and 35 men. FIELD STRENGTH/SEQUENCE: 3.0T MRI and elastography with vibration frequency of 120 Hz. ASSESSMENT: The 5-cm-width KT with full tension was placed on a single side of the lumbar paraspinal muscle. The taping side and adhering direction were randomly decided. Two rectangular regions of interest (ROIs) of 5- and 2.5-cm-width were positioned at the bilateral paraspinal regions from the L2 to L4 level on the confidence map of MR elastography before and after KT taping. The mean shear stiffness values of the ROIs at the superficial, middle, and deep depths were recorded; then the differences between the taping and reference sides were calculated. STATISTICAL TESTS: Paired t-test and Pearson correlations were used to evaluate the stiffness changes after KT application and intraoperator errors of the stiffness measures on the reference side, respectively. RESULTS: A significant decrease in the muscle stiffness value between taping and reference sides (-0.71 kPa ± 0.60 with KT and -0.25 kPa ± 0.78 without KT, P < 0.0001 for 5-cm ROI; -0.67 kPa ± 1.12 with KT and -0.16 kPa ± 1.17 without KT, P = 0.0004 for 2.5-cm ROI) was found in the superficial depth, but no significant differences in the middle and deep depths (P = 0.25 and P = 0.79 for 5-cm ROI; P = 0.09 and P = 0.67 for 2.5-cm ROI, respectively). There were no significant differences of muscle stiffness differences between gender (P = 0.11 for superficial, P = 0.37 for middle, P = 0.78 for deep) and taping direction (P = 0.18 for superficial, P = 0.13 for middle, P = 0.15 for deep). DATA CONCLUSION: Our results demonstrate that KT can reduce the MR elastography-derived shear stiffness in the superficial depth of paraspinal muscles. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:1039-1045.

Psychometric evaluation of a Chinese version of Lymphoedema Functioning, Disability and Health Questionnaire for Lower Limb Lymphoedema in women with gynaecological cancer surgery.

The prevalence of lower limb lymphoedema and its impact in gynaecological cancer patients is underestimated. However, a valid and reliable scale to measure lower leg lymphoedema in Taiwan has not been available. The purpose of the study was to translate the English version of Lymphoedema Functioning, Disability and Health Questionnaire for Lower Limb Lymphoedema into a Chinese version (Lymph-ICF-LL-C), and evaluate the psychometric properties of the Lymph-ICF-LL-C in Taiwanese women with gynaecological cancer surgery. A total of 170 women with gynaecological cancer surgery were recruited to examine the Lymph-ICF-LL-C. The Lymph-ICF-LL-C shows satisfactory internal consistency (Cronbach's alphas ≥ 0.84) and stability test-retest reliability (Intraclass correlation coefficient ≥0.55-0.90) at a 2-week interval. Exploratory factor analysis showed that 68.53% of the total variance was explained by a five-factor solution. The concurrent validity of the Lymph-ICF-LL-C was evidenced by a significant correlation with a fatigue scale (r = 0.46, p < 0.01) and with the bilateral difference of lower limb circumference (r = 0.24-0.36, all p < 0.01). The Lymph-ICF-LL-C can be used for assessing the life impact of lower limb lymphoedema, allowing appropriate interventions to prevent further deterioration and complications.

Fatigue-Induced Changes in Movement Pattern and Muscle Activity During Ballet Releve on Demi-Pointe.

Fatigue in ballet dancers may lead to injury, particularly in the lower extremities. However, few studies have investigated the effects of fatigue on ballet dancers' performance and movement patterns. Thus, the current study examines the effect of fatigue on the balance, movement pattern, and muscle activities of the lower extremities in ballet dancers. Twenty healthy, female ballet dancers performed releve on demi-pointe before and after fatigue. The trajectory of the whole body movement and the muscle activities of the major lower extremity muscles were recorded continuously during task performance. The results show that fatigue increases the medial-lateral center of mass (COM) displacement and hip and trunk motion, but decreases the COM velocity and ankle motion. Moreover, fatigue reduces the activities of the hamstrings and tibialis anterior, but increases that of the soleus. Finally, greater proximal hip and trunk motions are applied to compensate for the effects of fatigue, leading to a greater COM movement. Overall, the present findings show that fatigue results in impaired movement control and may therefore increase the risk of dance injury.

Fatigue-Induced Changes in Movement Pattern and Muscle Activity During Ballet Releve on Demi-Pointe.

Fatigue in ballet dancers may lead to injury, particularly in the lower extremities. However, few studies have investigated the effects of fatigue on ballet dancers' performance and movement patterns. Thus, the current study examines the effect of fatigue on the balance, movement pattern, and muscle activities of the lower extremities in ballet dancers. Twenty healthy, female ballet dancers performed releve on demi-pointe before and after fatigue. The trajectory of the whole body movement and the muscle activities of the major lower extremity muscles were recorded continuously during task performance. The results show that fatigue increases the medial-lateral center of mass (COM) displacement and hip and trunk motion, but decreases the COM velocity and ankle motion. Moreover, fatigue reduces the activities of the hamstrings and tibialis anterior, but increases that of the soleus. Finally, greater proximal hip and trunk motions are applied to compensate for the effects of fatigue, leading to a greater COM movement. Overall, the present findings show that fatigue results in impaired movement control and may therefore increase the risk of dance injury.

A Specific Cystography Pattern Can Predict Postprostatectomy Incontinence.

BACKGROUND: Postprostatectomy incontinence (PPI) is one of the most bothersome complications of radical prostatectomy. A postoperative image survey may better predict PPI than a preoperative survey. OBJECTIVE: The aim of this study was to determine whether postoperative cystography bladder patterns can predict PPI at short- and long-term follow-up. METHODS: In total, 180 patients who underwent robot-assisted radical prostatectomy (RARP) from September 2008 to September 2014, and who were followed for at least 6 months, were enrolled in this study. All patients underwent cystography within 2 weeks after RARP before Foley catheter removal, and all parameters were analyzed to evaluate the relationship with PPI at 1, 6, 12, and 24 months post-RARP. Patients were also divided into four bladder neck level groups, according to the relative position of the bladder neck to the pubic symphysis. RESULTS: A total of 119 patients were followed for at least 48 months after RARP. Cystography patterns were analyzed, including the downward bladder neck, bladder height, bladder width, height to width ratio, and bladder neck angle. A more downward bladder neck and a sharper bladder neck angle were significant predictors of PPI at 1, 6, 12, and 24 months after RARP. Patients with a larger bladder height or height to width ratio (prolate bladder shape) tended to have poor outcomes regarding PPI. Clinicians can also use a bladder neck level classification to rapidly predict the outcome of PPI. CONCLUSIONS: Postoperative cystography is a reliable and cost-effective tool for predicting PPI. A more downward bladder neck and a sharper bladder neck angle have the greatest predictive power for short- and long-term PPI.

Biomechanical analysis of knee and trunk in badminton players with and without knee pain during backhand diagonal lunges.

The contribution of core neuromuscular control to the dynamic stability of badminton players with and without knee pain during backhand lunges has not been investigated. Accordingly, this study compared the kinematics of the lower extremity, the trunk movement, the muscle activation and the balance performance of knee-injured and knee-uninjured badminton players when performing backhand stroke diagonal lunges. Seventeen participants with chronic knee pain (injured group) and 17 healthy participants (control group) randomly performed two diagonal backhand lunges in the forward and backward directions, respectively. This study showed that the injured group had lower frontal and horizontal motions of the knee joint, a smaller hip-shoulder separation angle and a reduced trunk tilt angle. In addition, the injured group exhibited a greater left paraspinal muscle activity, while the control group demonstrated a greater activation of the vastus lateralis, vastus medialis and medial gastrocnemius muscle groups. Finally, the injured group showed a smaller distance between centre of mass (COM) and centre of pressure, and a lower peak COM velocity when performing the backhand backward lunge tasks. In conclusion, the injured group used reduced knee and trunk motions to complete the backhand lunge tasks. Furthermore, the paraspinal muscles contributed to the lunge performance of the individuals with knee pain, whereas the knee extensors and ankle plantar flexor played a greater role for those without knee pain.

Effect of ankle kinesio taping on vertical jump with run-up and countermovement jump in athletes with ankle functional instability.

[Purpose] Limited research has been performed in spite of biomechanical evaluation of jump landing with kinesio taping. Therefore, the main objective of this study was to evaluate the effect of kinesio taping applied to athletes. In this study, the authors wished to investigate the effect of kinesio taping during a vertical jump with run-up and countermovement jump on ankle functional instability. [Subjects and Methods] Ten male athletes with ankle functional instability (FI) were recruited in this study from a college volleyball team. Each participant was requested to perform two tasks, the countermovement jump and vertical jump with run-up. Infrared high-speed cameras and force plates were used to assess the effect of ankle taping. [Results] The results showed that the peak ground reaction force in the sagittal plane during a vertical jump with run-up slowed down after kinesio taping and that the peak ankle plantar flexion moment in both types of jump also decreased. [Conclusion] In conclusion, this study proved the effect of kinesio taping on ankle functional instability, which was evaluated by measuring the vertical ground reaction force and peak plantar flexion moment. Its finding may allow us to provide some recommendations for athletes and trainers.

How does knee pain affect trunk and knee motion during badminton forehand lunges?

Badminton requires extensive lower extremity movement and a precise coordination of the upper extremity and trunk movements. Accordingly, this study investigated motions of the trunk and the knee, control of dynamic stability and muscle activation patterns of individuals with and without knee pain. Seventeen participants with chronic knee pain and 17 healthy participants participated in the study and performed forehand forward and backward diagonal lunges. This study showed that those with knee pain exhibited smaller knee motions in frontal and horizontal planes during forward lunge but greater knee motions in sagittal plane during backward lunge. By contrast, in both tasks, the injured group showed a smaller value on the activation level of the paraspinal muscles in pre-impact phase, hip-shoulder separation angle, trunk forward inclination range and peak centre of mass (COM) velocity. Badminton players with knee pain adopt a more conservative movement pattern of the knee to minimise recurrence of knee pain. The healthy group exhibit better weight-shifting ability due to a greater control of the trunk and knee muscles. Training programmes for badminton players with knee pain should be designed to improve both the neuromuscular control and muscle strength of the core muscles and the knee extensor with focus on the backward lunge motion.

Influence of ankle injury on muscle activation and postural control during ballet grand plié.

Ballet deep squat with legs rotated externally (grand plié) is a fundamental movement for dancers. However, performing this task is a challenge to ankle control, particularly for those with ankle injury. Thus, the purpose of this study was to investigate how ankle sprains affect the ability of postural and muscular control during grand plié in ballet dancers. Thirteen injured dancers and 20 uninjured dancers performed a 15 second grand plié consisting of lowering, squatting, and rising phases. The lower extremity motion patterns and muscle activities, pelvic orientation, and center of pressure (COP) excursion were measured. In addition, a principal component analysis was applied to analyze waveforms of muscle activity in bilateral medial gastrocnemius, peroneus longus, and tibialis anterior. Our findings showed that the injured dancers had smaller pelvic motions and COP excursions, greater maximum angles of knee flexion and ankle dorsiflexion as well as different temporal activation patterns of the medial gastrocnemius and tibialis anterior. These findings suggested that the injured dancers coped with postural challenges by changing lower extremity motions and temporal muscle activation patterns.

Physical Therapy Intervention Effects on Alteration of Spinal Excitability in Patients With Chronic Ankle Instability: A Systematic Review and Meta-analysis.

CONTEXT: Chronic ankle instability (CAI) is a common injury in athletes. Different forms of physical therapy have been applied to the population with CAI to assess their impact on spinal excitability. OBJECTIVE: The purpose of this systematic review and meta-analysis was to investigate the effectiveness of various physical therapy interventions on the alteration of spinal excitability in patients with CAI. DATA SOURCES: Four databases (EMBASE, MEDLINE, Cochrane CENTRAL, and Scopus) were searched from inception to November 2022. STUDY SELECTION: A total of 253 studies were obtained and screened; 11 studies on the effects of physical therapy intervention on the alteration of spinal excitability in patients with CAI were identified for meta-analysis. STUDY DESIGN: Systematic review and meta-analysis. LEVEL OF EVIDENCE: Level 3a. DATA EXTRACTION: A total of 11 studies that included the maximal Hoffmann reflex normalized by the maximal muscle response (H/M ratio) in the peroneus longus and soleus muscles were extracted and summarized. The quality of the studies was assessed using the PEDro scale. RESULTS: The extracted studies had an average PEDro score of 4.7 ± 1.4, indicating that most of them had fair-to-good quality. The physical therapy interventions included cryotherapy, taping, mobilization, proprioceptive training, and dry needling. The overall effects showed that the H/M ratios of the peroneus longus (P = 0.44, I2 = 0%) and soleus (P = 0.56,I2 = 22%) muscles were not changed by physical therapy in patients with CAI. CONCLUSION: The meta-analysis indicated that physical therapy interventions such as cryotherapy, taping, mobilization, proprioceptive training, and dry needling do not alter the spinal excitability in patients with CAI. Given that only 1 study reported ineffective changes in spinal excitability with dry needling, more research is essential to establish and validate its efficacy. PROSPERO REGISTRATION: CRD42022372998.

Differences in the Rotation Axis Between Professional and Experienced Amateur Ballet Dancers During pirouette en dehour in Classical Ballet With Wearing Pointe Shoes: A Pilot Study.

Introduction: En pointe, in which weight is placed on the tiptoes, is a fundamental practice for female ballet dancers with pointe shoes. The center of mass (COM) is maintained over the base of support and the relative position of COM to the center of pressure (COP) is especially important when conducting a pirouette in ballet. A pirouette is a fundamental turn in classical ballet with flat shoes and pointe shoes. The investigation of the turn with pointe shoes would be favorable for understanding the movement with limited base of support. Herein, we aimed to determine the differences in the ability to perform pirouettes with pointe shoes between professional and amateur ballet dancers. Methods: This study included 8 professional and 9 amateur ballet dancers. The dancers performed a single pirouette, and the movement was captured and analyzed in 3 phases: turning with double-leg support (TDS), turning with single-leg support in pre-swing (TSSp), and turning with single-leg support in mid-swing (TSSm). The analysis focused on the inclination between the vertical angle and the COP-COM line, the vertical maximum reaction force, and the jump-up time in each phase. Results: The results showed no significant differences between the TDS and TSSp. However, professional ballet dancers exhibited significantly lesser posterior inclinations (professional; 2.05° ± 0.90°, amateur; 3.88° ± 1.67°) and jump-up time (professional; 0%, amateur; 1.4% ± 1.3%) than amateur dancers during TSSm. Conclusion: Overall, the findings suggest that professional dancers exhibit superior control skills regarding the COP-COM line than amateur dancers during TSSm. These results may be attributed to the fact that professional dancers can maintain the COM as close to the upright as on the COP without jumping during TSSm. This enables professional dancers to conduct the movements esthetically and continue on to the other movements in the dance phase.

Influence of altered torsional stiffness through sole modification of air pressure shoes on lower extremity biomechanical behaviour during side-step cutting maneuvers.

Directional changes in cutting maneuvers are critical in sports, where shoe torsional stiffness (STS) is an important factor. Shoes are designed based on different constructions and movement patterns. Hence, it is unclear how adjustable spacers into the sole constructions of air pressure chambers (APC) affect the STS in side-step cutting. Therefore, this study investigated the effects of altered STS through adjustable sole spacers on ground reaction force (GRF) and ankle and knee joint moments in side-step cutting. Seventeen healthy recreational athletes performed side-step cutting with experimental conditions including (i) barefoot (BF), (ii) unaltered shoes (UAS): soles consisting of APC, and (iii) altered shoes (AS): modified UAS by inserting elastomeric spacers into cavities formed by APC. Mechanical and biomechanical variables were measured. Significant differences were revealed across shoe conditions for impact peak (p = 0.009) and impulse (p = 0.018) in vertical GRF, time to achieve peak braking (p = 0.004), and peak propulsion (p = 0.025) for anterior-posterior GRF in ANOVA test. No significant differences were observed in GRF peaks and impulses between UAS and AS except for a trend of differences in impact peak (p = 0.087) for vertical GRF. At the ankle and knee joint, peak ankle power absorption (p = 0.019), peak knee internal rotation moment (p = 0.042), peak knee extension moment (p = 0.001), peak knee flexion moment (0.000), peak knee power absorption (p = 0.047) showed significant difference across three shoe conditions. However, no significant differences between the UAS and AS were noticed for peak joint moments and power. Altered shoe torsional stiffness did not significantly affect the peak forces and peak ankle and knee joint moments or powers; hence sole adjustment did not influence the cutting performance. This study might be insightful in sports footwear design, and adjusting shoe torsional stiffness by sole modification might be advantageous for athletes playing sports with cutting maneuvers to reduce the risk of injuries by controlling the twisting force at the ankle that frequently happens during cutting maneuvers.

The role of muscle function and pointe shoe characteristics in Arabesque movement among ballet dancers with non-specific low back pain.

This study aimed to investigate posterior chain muscle function and the influence of pointe shoes in ballet dancers with and without low back pain (LBP) in the Arabesque. Twenty-nine young professional ballet dancers (17 with LBP and 12 healthy controls) were recruited. Muscle strength and mechanical properties of the erector spinae and hamstrings were assessed. The displacement of centre of mass (COM) during Arabesque under different shoe conditions (R-class, Chacott, and own shoes) was measured with a motion capture system. The LBP group exhibited greater dynamic stiffness and decreased mechanical stress relaxation time in the lateral hamstring compared to the control group. During Arabesque, the LBP group demonstrated significantly greater anterior-posterior displacement of the COM and a larger percentage of time to achieve maximal trunk extension angle. The COM displacement in vertical and medial-lateral directions was smaller in the R-class than in their own shoes. LBP impacts muscle mechanical properties, particularly in the lateral hamstring. The compromised muscle function resulted in a longer time to spinal extension during Arabesque, signifying that reduced trunk control contributed to greater COM displacement. Hence, it is essential to emphasise that evaluating muscle properties and dynamic postural control is imperative for dancers experiencing LBP.

Effect of adaptive sports on quality of life in individuals with disabilities who use wheelchairs: a mixed-methods systematic review.

PURPOSE: Adaptive sports participation has been shown to improve quality of life (QoL) in individual with disabilities. However, inconsistent results in various domains of QoL exist in the literature. The objective of this mixed-methods systematic review is to identify and synthesize evidence from quantitative and qualitative studies on the effect of adaptive sports on QoL in individuals with disabilities who use wheelchairs for mobility. METHODS: A systematic literature review of quantitative, qualitative, and mixed-methods research on the effect of adaptive sports on QoL was conducted on five databases (Scopus, Web of Science, PsycINFO, Medline, and PubMed). Quality appraisal was conducted by two authors by using the Mixed Methods Appraisal Tool. RESULTS: This review identified 4 key findings from 41 studies, including 31 quantitative and 10 qualitative studies. First, individuals with disabilities using wheelchairs for mobility who actively engaged in adaptive sports tend to report higher QoL scores compared with those who were inactive or did not participate. Second, the relationship between the duration of regular participation in adaptive sports and QoL scores exhibited inconsistent results. Third, a multi-component adaptive sports program demonstrates the potential to further improve QoL scores. Last, qualitative investigations reveal that participation in adaptive sports positively influences various domains of well-being in wheelchair users, including encompassing physical and emotional well-being, interpersonal relationships, material well-being, personal development, self-determination, and social inclusion. CONCLUSION: This review provides a comprehensive relationship between adaptive sports participation and QoL of wheelchair users. This study identifies the value of multi-component interventions and demonstrates the diverse positive influences of adaptive sports on well-being.

Individuals with disabilities who actively engage in adaptive sports report higher quality of life (QoL) scores compared with those who were inactive or did not participate.The relationship between the duration of regular participation in adaptive sports and QoL scores exhibits inconsistent results.A multi-component adaptive sports program may further improve QoL scores.Qualitative investigations reveal that participation in adaptive sports positively influences various domains of well-being in wheelchair users, including encompassing physical and emotional well-being, interpersonal relationships, material well-being, personal development, self-determination, and social inclusion.