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Hemophilic arthropathy causes the damage of synovium, cartilage, and subchondral bone. The present study evaluated the safety and the effect of extracorporeal shockwave therapy (ESWT), a safe treatment widely used in musculoskeletal conditions in patients with hemophilic arthropathy. Between 1 August 2019 and 31 July 2020, seven hemophilia A patients were enrolled and treated with medium-energy ESWT on the knee joint in the first two months after prophylactic coagulation factor administration. At the beginning of the study and at 1-, 2-, 3-, and 6-month follow-ups, the Hemophilia Joint Health Score (HJHS), visual analog scale score (VAS), and Hemophilia Early Arthropathy Detection with Ultrasound score (HEAD-US) were evaluated for therapeutic effectiveness and safety, while serum bone morphogenetic protein 2 (BMP-2) and von Willebrand factor (vWF) levels were analyzed for assessing chondroprotection and bone healing. Magnetic resonance imaging (MRI) of the knee was performed at the beginning of the study and the 6-month follow-ups. As a result, a non-significant decrease in VAS scores (p = 0.151) but not HJHS after treatment was noticed. At the 3-month follow-up, there was a non-significant increase in BMP2 levels (p = 0.171) but not vWF. Ultrasonography showed no disease activity score elevation in five patients and no further disease damage in all patients. Repeated MRI examinations in three patients showed no structural progression during the 6-month follow-up. As to adverse events, redness, local heat, and mild swelling were noted in five patients without breakthrough bleeding. We concluded that medium-energy ESWT might be safe for hemophilic arthropathy once prophylactic coagulation factors are administered.

The serial interval distribution is used to approximate the generation time distribution, an essential parameter to predict the effective reproductive number “Rt”, a measure of transmissibility. However, serial interval distributions may change as an epidemic progresses rather than remaining constant. Here we show that serial intervals in Hong Kong varied over time, closely associated with the temporal variation in COVID-19 case profiles and public health and social measures that were implemented in response to surges in community transmission. Quantification of the variation over time in serial intervals led to improved estimation of Rt, and provided additional insights into the impact of public health measures on transmission of infections.One-Sentence SummaryReal-time estimates of serial interval distributions can improve assessment of COVID-19 transmission dynamics and control.

This is a report of the RGC-TBRS funded observational pilot study which examines the effects of personal exposures to three types of air pollutants, namely, PM1.0, PM2.5, and PM10, on personal health condition and perception of young asthmatics (aged 12 – 15) in Hong Kong. This is the first study to investigate the relationship between PM1.0 and FEV1 and FVC of young asthmatics in Hong Kong, based on personal exposures obtained from portable sensors. Our preliminary results show that a higher level of PM1.0, PM2.5 and PM10 would deteriorate the health conditions of young asthmatics in HK. All correlations between particulates and lung functions are significant and negative, including PM1.0 exposure vs. FEV1 (R2=12%; p=0.023), PM1.0 exposure vs. FVC (R2=15%; p=0.010), PM2.5 exposure vs. FEV1 (R2=13%; p=0.019), PM2.5 exposure vs. FVC (R2=16%; p=0.008), PM10 exposure vs. FEV1 (R2=14%; p=0.012), and PM10 exposure vs. FVC (R2=18%; p=0.005). Moreover, after accounting for covariates, including age, gender, body mass index (BMI), temperature, and relative humidity, we found a significant relationship between PM1.0 exposure vs. FVC (Coefficient=-0.1224; p=0.032), PM2.5 exposure vs. FVC (Coefficient=-0.1177; p=0.021), PM10 exposure vs. FEV1 (Coefficient=-0.0703; p=0.019), and PM10 exposure vs. FVC (Coefficient=-0.1204; p=0.006). Further, using the pilot study data, we have performed a power analysis to estimate the sample size for our follow-up main study. Based on the primary null hypothesis that personal PM exposure would not change the FEV1 and FVC of young asthmatics in HK, the lowest sample size that gives 80% power at a 5% significance level is 107. Hence, the sample size (or the total number of participated asthma subjects) expected for the follow-up longitudinal clinical study should be 125 (after adjusting for the non-compliance and withdrawal of subjects). Our pilot study has demonstrated the feasibility of research into the effects of personal air pollutant exposure on health condition and health perception. Our follow-up study will address the challenges identified in the pilot study, based on the proposed follow-up actions for subject engagement, data collection, and data analysis.

A statistical framework was developed to jointly estimate the distribution of generation time and incubation period from human-to-human transmission pairs of COVID-19, accounting for sampling biases due to exponential growth of the epidemic during the data collection period., Background Coronavirus disease 2019 (COVID-19) has caused a heavy disease burden globally. The impact of process and timing of data collection on the accuracy of estimation of key epidemiological distributions are unclear. Because infection times are typically unobserved, there are relatively few estimates of generation time distribution. Methods We developed a statistical framework to jointly estimate generation time and incubation period from human-to-human transmission pairs, accounting for sampling biases. We applied the framework on 80 laboratory-confirmed human-to-human transmission pairs in China. We further inferred the infectiousness profile, serial interval distribution, proportions of presymptomatic transmission, and basic reproduction number (R0) for COVID-19. Results The estimated mean incubation period was 4.8 days (95% confidence interval [CI], 4.1–5.6), and mean generation time was 5.7 days (95% CI, 4.8–6.5). The estimated R0 based on the estimated generation time was 2.2 (95% CI, 1.9–2.4). A simulation study suggested that our approach could provide unbiased estimates, insensitive to the width of exposure windows. Conclusions Properly accounting for the timing and process of data collection is critical to have correct estimates of generation time and incubation period. R0 can be biased when it is derived based on serial interval as the proxy of generation time.

BackgroundThe hemophilic arthropathy was caused by repeated joint bleeding, which resulted in joint synovium hyperplasia, cartilage damage and bone deformity. Extracorporeal shockwave treatment (ESWT) is a non-invasive treatment with high safety and has been widely used in the treatment of various musculoskeletal conditions. This study was aimed to evaluate the safety of ESWT in hemophilic arthropathy of the knee.MethodsThis is a prospective single blind randomized control study conducted between 2019/08/01 and 2020/07/31. Hemophilia and Von Willebrand disease patients were enrolled and randomized for extracorporeal shock wave therapy to the left or right knee joint and energy-free sham therapy to the other knee joint at the 1st and 2nd month after prophylactic coagulation factor administration. As safety evaluation, hemophilia joint health score (HJHS), knee score scale (KSS), visual analog scale (VAS) and ultrasound (HEAD-US) were checked at the beginning, 1st, 2nd, 3rd and 6th month. Knee MRI was examined at the beginning and 6th month.ResultsHJHS score of the knee receiving real ESWT did not elevate in 9 patients (75%). KSS demonstrated neither significant improvement nor deterioration after ESWT. VAS declined after two sessions of ESWT. Ultrasound and MRI showed no breakthrough joint bleeding nor progression of previously existed effusion and hemarthrosis.ConclusionESWT might be a safe treatment for hemophilic arthropathy once prophylactic coagulation factors are adequately administrated before ESWT. Further well-controlled study enrolling more hemophilia patients might be needed for the effectiveness of ESWT on these patients.

We report temporal patterns of viral shedding in 94 patients with laboratory-confirmed COVID-19 and modeled COVID-19 infectiousness profiles from a separate sample of 77 infector–infectee transmission pairs. We observed the highest viral load in throat swabs at the time of symptom onset, and inferred that infectiousness peaked on or before symptom onset. We estimated that 44% (95% confidence interval, 30–57%) of secondary cases were infected during the index cases’ presymptomatic stage, in settings with substantial household clustering, active case finding and quarantine outside the home. Disease control measures should be adjusted to account for probable substantial presymptomatic transmission. Presymptomatic transmission of SARS-CoV-2 is estimated to account for a substantial proportion of COVID-19 cases.

The world has well and truly entered the digital age where technology is ever-present and all pervasive. The development of technological innovations facilitate our everyday lives. But they also ma...

We used national sentinel surveillance data in China for 2005-2016 to examine the lineage-specific epidemiology of influenza B. Influenza B viruses circulated every year with relatively lower activity than influenza A. B/Yamagata was more frequently detected in adults than in children.

Joint replacement, especially hip and knee, are increasingly common elective orthopaedic procedures. Patients who undergo these operations are usually elderly and may have multiple comorbidities requiring careful perioperative management. Specific issues include deep venous thromboembolism (DVT) prophylaxis and use of regional anaesthesia, potential blood loss and hypothermia, application of pneumatic tourniquet and use of bone cement, and postoperative mobilization. There is a trend for developing clinical pathways or protocols from preoperative assessment through postoperative pain management to improve outcomes and enhance recovery in these patients.

Two lineages of influenza B virus currently co-circulate and have distinct antigenicity, termed Victoria and Yamagata after the B/Victoria/2/87 and B/Yamagata/16/88 strains, respectively. We analyzed antibody titer dynamics following PCR-confirmed influenza B virus infection in a longitudinal community-based cohort study conducted in Hong Kong from 2009–2014 to assess patterns in changes in antibody titers to B/Victoria and B/Yamagata viruses following infections with each lineage. Among 62 PCR-confirmed cases, almost half had undetectable hemagglutination inhibition (HAI) antibody titers to the lineage of infection both pre-infection and post-infection. Among those infected with influenza B/Victoria who showed an HAI titer response after infection, we found strong rises to the lineage of infection, positive but smaller cross-lineage HAI titer boosts, a small dependence of HAI titer boosts on pre-infection titers, and a shorter half-life of HAI titers in adults. Our study is limited by the low HAI sensitivity for non-ether-treated IBV antigen and the incapacity of performing other assays with higher sensitivity, as well as the mismatch between the B/Yamagata lineage circulating strain and the assay strain in one of the study seasons.

Summary: Background: The estimation of influenza-associated excess mortality in countries can help to improve estimates of the global mortality burden attributable to influenza virus infections. We did a study to estimate the influenza-associated excess respiratory mortality in mainland China for the 2010–11 through 2014–15 seasons. Methods: We obtained provincial weekly influenza surveillance data and population mortality data for 161 disease surveillance points in 31 provinces in mainland China from the Chinese Center for Disease Control and Prevention for the years 2005–15. Disease surveillance points with an annual average mortality rate of less than 0·4% between 2005 and 2015 or an annual mortality rate of less than 0·3% in any given years were excluded. We extracted data for respiratory deaths based on codes J00-J99 under the tenth edition of the International Classification of Diseases. Data on respiratory mortality and population were stratified by age group (age

Background Human influenza virus infections cause a considerable burden of morbidity and mortality worldwide each year. Understanding regional influenza‐associated outpatient burden is crucial for formulating control strategies against influenza viruses. Methods We extracted the national sentinel surveillance data on outpatient visits due to influenza‐like‐illness (ILI) and virological confirmation of sentinel specimens from 30 provinces of China from 2006 to 2015. Generalized additive regression models were fitted to estimate influenza‐associated excess ILI outpatient burden for each individual province, accounting for seasonal baselines and meteorological factors. Results Influenza was associated with an average of 2.5 excess ILI consultations per 1000 person‐years (py) in 30 provinces of China each year from 2006 to 2015. Influenza A(H1N1)pdm09 led to a higher number of influenza‐associated ILI consultations in 2009 across all provinces compared with other years. The excess ILI burden was 4.5 per 1000 py among children aged below 15 years old, substantially higher than that in adults. Conclusions Human influenza viruses caused considerable impact on population morbidity, with a consequent healthcare and economic burden. This study provided the evidence for planning of vaccination programs in China and a framework to estimate burden of influenza‐associated outpatient consultations.

To investigate the effects of radial extracorporeal shock wave therapy (rESWT) and to determine the posttreatment common extensor tendon stiffness among patients with lateral epicondylosis.Thirty patients with lateral epicondylosis were randomly divided into experimental and control groups. Participants in the experimental group received rESWT plus physical therapy, and those in the control group received sham shock wave plus physical therapy for 3 weeks. Visual analog scale; grip strength dynamometer; Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire; and ultrasonography in 2-dimensional image, and real-time sonoelastography were used in the assessments at baseline and after 6, 12, and 24 weeks (T3).The experimental group had more significant pain reduction at T3 than the control group. Compared with the control group, the experimental group had significantly higher maximal grip strength at 12 and 24 weeks, with significant increases. Compared to baseline, the experimental group had significantly lower Taiwan version DASH disability/symptom scores and work module scores at all posttreatment follow-up points. Five participants in the experimental group had partial tear within common extensor tendon at their involved elbow, and all the tears totally healed at T3. However, the inter-rater reliabilities for real-time sonoelastography were poor to fair.Patients with lateral epicondylosis had better and faster pain reduction, grip strength increase, and functional improvement after receiving rESWT in addition to physical therapy than those who received physical therapy only.

Stenosing tenosynovitis of the posterior tibial tendon is a cause of posteromedial ankle pain. Conservative treatment is often ineffective, and surgery is usually required for alleviation of symptoms. Stenosis of the tendon sheath can be overcome by release of the tendon sheath or deepening of the retromalleolar groove. These procedures can be performed endoscopically. The purpose of this Technical Note is to describe the technical details of endoscopic release of the posterior tibial tendon sheath with the advantage of minimal soft tissue dissection and titrated tendon sheath release according to the extent of stenosis. Associated tendon pathology and hindfoot malalignment should be treated accordingly.

Objective To evaluate the relationships among spino-pelvic parameters, trunk balance and functional disability in patients with degenerative lumbar spondylolisthesis. Design Cross-sectional study. Subjects Forty-five patients with degenerative lumbar spondylolisthesis and 32 patients without degenerative lumbar spondylolisthesis. Methods Spino-pelvic parameters (pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis) and pain severity were evaluated. Biodex balance tests (postural stability, limits of stability, modified clinical test of sensory interaction and balance, fall risk) and Quebec Back Pain Disability Scale (QBDS) scores were measured. Results Intergroup differences were found in age, low back pain, limits of stability, pelvic incidence, pelvic tilt and some subscales of QBDS. Correlations were found: (i) in the degenerative lumbar spondylolisthesis group: between pelvic incidence and sacral slope/pelvic tilt/lumbar lordosis/height/limits of stability; sacral slope and lumbar lordosis/height/limits of stability/modified clinical test of sensory interaction and balance (eyes closed on foam); lumbar lordosis and body mass index/QBDS/postural stability/modified clinical test of sensory interaction and balance (eyes open and eyes closed on foam); (ii) in the non-degenerative lumbar spondylolisthesis group: between pelvic incidence and pelvic tilt; pelvic tilt and sacral slope/lumbar lordosis; sacral slope and lumbar lordosis/fall risk. All spino-pelvic parameters in the degenerative lumbar spondylolisthesis group and pelvic tilt in the non-degenerative lumbar spondylolisthesis group correlated with QBDS. Conclusion Pelvic tilt was the major compensating factor in both groups (patients with and without degenerative lumbar spondylolisthesis). Sacral slope and lumbar lordosis contributed to partial compensation in the degenerative lumbar spondylolisthesis group. Lumbar lordosis correlated with body mass index. Sacral slope could be an indicator of fall risk in the non-degenerative lumbar spondylolisthesis group.

Summary Background The protection conferred by influenza vaccination is generally thought to last less than a year, necessitating annual revaccination. However, the speed with which influenza vaccine effectiveness might decline during a year is unknown, which is of particular importance for locations with year-round influenza activity. We aimed to assess how influenza vaccine effectiveness changes by time intervals between vaccination and admission to hospital, taking advantage of almost year-round circulation of influenza in Hong Kong. Methods In this test-negative case-control study, we analysed vaccine effectiveness in children (aged 6 months to 17 years) who were admitted to hospital in Hong Kong over 5 consecutive years (2012–17). We included those who were admitted to general wards in four public hospitals in Hong Kong with a fever (≥38°C) and any respiratory symptom, such as runny nose, cough, or sore throat. We used direct immunofluorescence assay and reverse transcription PCR to detect influenza virus infection, and recorded children's influenza immunisation history. We compared characteristics of positive cases and negative controls and examined how vaccine effectiveness changed by time between vaccination and admission to hospital with regression analyses. Findings Between Sept 1, 2012, and Aug 31, 2017, we enrolled 15 695 children hospitalised for respiratory infections, including 2500 (15·9%) who tested positive for influenza A or B and 13 195 (84·1%) who tested negative. 159 (6·4%) influenza-positive cases and 1445 (11·0%) influenza-negative cases had been vaccinated. Most vaccinations were done by December of each influenza vaccination season. Influenza-related admissions to hospital occurred year-round, with peaks in January through March in most years and a large summer peak in 2016; pooled vaccine effectiveness for children of all ages was 79% (95% CI 42–92) for September to December, 67% (57–74) for January to April, and 43% (25–57) for May to August. Vaccine effectiveness against influenza A or B was estimated as 79% (95% CI 64–88) within 0·5–2 months of vaccination, 60% (46–71) within >2–4 months, 57% (39–70) within >4–6 months, and 45% (22–61) within >6–9 months. In separate analyses by type and subtype, we estimated that vaccine effectiveness declined by 2–5 percentage points per month. Interpretation Influenza vaccine effectiveness decreased during the 9 months after vaccination in children in Hong Kong. Our findings confirm the importance of annual vaccination in children. Influenza vaccines that provide broader and longer-lasting protection are needed to provide year-round protection in regions with irregular influenza seasonality or lengthy periods of influenza activity. Funding Health and Medical Research Fund, Hong Kong and the Research Grants Council, Hong Kong.

Wong AM, Pei Y-C, Hong W-H, Chung C-Y, Lau Y-C, Chen CP. Foot contact pattern analysis in hemiplegic stroke patients: an implication for neurologic status determination. Arch Phys Med Rehabil 2004;85:1625–30. Objective To investigate the feasibility of using a foot contact pattern to predict neurologic recovery and the effect of ambulation training in hemiplegic stroke patients. Design Case-comparison study. Setting Gait laboratory in a tertiary care center. Participants Sixty-five functionally ambulant hemiplegic stroke patients, and 30 healthy subjects serving as the control group. Interventions Gait analyses were performed by using the conventional gait analysis system (6 cameras) and the portable Computer DynoGraphy (CDG) system. Main outcome measures Walking velocity, step length, and cadence were measured from the conventional gait analysis system. Cyclogram, gaitline, and ground reaction force (GRF) patterns were recorded with the CDG system. Results Velocity, cadence, and step length increased in higher Brunnstrom stages ( P P Conclusions Foot contact pattern can be a simple and reliable indicator of hemiplegic gait in stroke patients. It is closely related to patient's neurologic status and is correlated with parameters obtained from conventional gait analysis systems. Pathologic presentations are noted in both the affected and unaffected limbs, suggesting that rehabilitation programs should be implemented on both sides.

Tang SF, Chen CP, Chen MJ, Pei Y-C, Lau Y-C, Leong C-P. Changes in sagittal ground reaction forces after intra-articular hyaluronate injections for knee osteoarthritis. Arch Phys Med Rehabil 2004;85:951–5. Objectives To examine the gait patterns and the sagittal ground reaction forces (GRFs) in persons with knee osteoarthritis (OA) after intra-articular injection of hyaluronate and to investigate the duration of its treatment effectiveness. Design Case-comparison study. Setting Gait laboratory in a tertiary care center. Participants Fifteen subjects (30 knees) with symptomatic knee OA (stage I or II, according to the Ahlback grading system), and 15 age-, mass-, and gender-matched non-OA control subjects (30 knees). Intervention After initial gait analysis, the group with knee OA received 5 weekly intra-articular injections of hyaluronate to bilateral knees. Gait analysis was performed again for the group with knee OA after the completion of hyaluronate injections. Main outcome measures Forceplate sagittal GRFs and gait parameters of velocity, cadence, step length, and stride time. Results The distinctive 2-peak force vector GRF was lost in persons with knee OA. The first peak rise time was significantly delayed ( P P Conclusions Gait patterns and GRFs improved significantly after intra-articular knee injection of hyaluronate in persons with Ahlback stages I and II knee OA. The clinical treatment effect was immediate and may last for 6 months or more.

Crime has traditionally been a domestic concern for nation-states, with individual jurisdictions having their own responsibility for policing, prosecution, criminal trial, and the imposition of judicial punishments. Although some conventional crime types, such as maritime piracy, smuggling, and organized crime have always crossed jurisdictional borders and required transnational cooperation for investigation and judicial responses, it was not until the mid-twentieth century that crime became a more globalized phenomenon. As Findlay (1999, p. 2) observed: The globalisation of capital from money to the electronic transfer of credit, of transactions of wealth from the exchange of property to info-technology, and the seemingly limitless expanse of immediate and instantaneous global markets, have enabled the transformation of crime beyond people, places and even identifiable crimes.

Foreword The Hon. Charles Mok 1. Introduction: Cybercrime Risks and Responses - Eastern and Western Perspectives Russell G Smith, Ray Chak-Chung Cheung and Laurie Yiu-Chung Lau PART I: UNDERSTANDING CYBERCRIME THROUGH RESEARCH 2. Trajectories of Cybercrime Russell G. Smith 3. Ethical, Legal and Methodological Considerations in Cyber-Research: Conducting a Cyber-Ethnography of www.bullying.org Barry E. Cartwright 4. That Cyber-Routines, That Cybervictimization: Profiling Victimes of Cybercrime Fernando Miro PART II: CONTEMPORARY CYBERCRIME RISKS 5. Organized Cybercrime and National Security Peter Grabosky 6. Internet Fraud in Hong Kong: An Analysis of a Sample of Court Cases Laurie Yiu-Chung Lau 7. The Role of Spam in Cybercrime Data from the Australian Cybercrime Pilot Observatory Mamoun Alazab and Roderic Broadhurst 8. Quantifying Sexually Explicit Language George Weir 9. Spreading the Message Digitally A Look Into Extremist Organizations' Use of the Internet Richard Frank, Martin Bouchard, Garth Davies and Joseph Mei 10. Criminals in the Cloud: Crime, Security Threats and Prevention Measures Alice Hutchings, Russell G. Smith and Lachlan James PART III: INDUSTRY, CRIMINAL JUSTICE AND FORENSIC RESPONSES TO CYBERCRIME 11. Hong Kong's Experience in Strengthening the Security Measures of Retail Payment Services Shu-Pui Li 12. Banking Security: A Hong Kong Perspective Paul Tak Shing Liu 13. Complicity in Cyberspace: Applying Doctrines of Accessorial Liability to Online Groups Gregor Urbas 14. Profiling Cybercrime Perpetrators in China and Its Policy Countermeasures Darrell Chan and Dawei Wang PART IV: PRIVACY AND FREEDOM ONLINE 15. When Privacy Meets Social Networking Sites - With Special Reference to Facebook Yachi Chiang 16. An Introduction of Cyber-Crowdsourcing (Human Flesh Searching) in the Greater China Region Lennon Y.C. Chang and Andy K.H. Leung 17. Hacktivism and Whistleblowing in the Era of Forced Transparency? Alana Maurushat

This chapter analyzes a selection of court cases concerning Internet crimes, particularly those involving Internet banking fraud. The rule of law is a core value of the government in Hong Kong, which seeks to provide a secure environment in which both individuals and organizations can transact business both online and offline. This chapter provides a snapshot of how Hong Kong’s Internet governance regime operates by examining a sample of Internet fraud cases from the mid-1990s. It shows how the rule of law has helped Hong Kong to achieve its place as an economic hub in Asia.

Objective Patients with osteoporotic vertebral compression fracture (OVCF) have postural changes and increased risk of falling. The aim of this study is to compare balance characteristics between patients with OVCF and healthy control subjects. Methods Patients with severe OVCF and control subjects underwent computerised dynamic posturography (CDP) in this case-control study. Results Forty-seven OVCF patients and 45 controls were recruited. Compared with the control group, the OVCF group had significantly decreased average stability; maximal stability under the `eye open with swayed support surface' (CDP subtest 4) and 'eye closed with swayed support surface' conditions (subtest 5); and decreased ankle strategy during subtests 4 and 5 and under the `swayed vision with swayed support surface' condition (subtest 6). The OVCF group fell more frequently during subtests 5 and 6 and had longer overall reaction time and longer reaction time when moving backward during the directional control test. Conclusion OVCF patients had poorer static and dynamic balance performance compared with normal control. They had decreased postural stability and ankle strategy with increased fall frequency on a swayed surface; they also had longer reaction times overall and in the backward direction. Therefore, we suggest balance rehabilitation for patients with OVCF to prevent fall.

Analysis of electromyographic (EMG) activities in the back during dynamic exercise is needed because more complex loading on the spine is created in comparison with that during static exercise. The purpose of this study is to investigate the difference in bilateral midback and low-back paraspinal muscle (PSM) activities during performance of different resistance isokinetic exercises in healthy subjects and those with scoliosis.Forty-one healthy subjects and thirty-three subjects with adolescent idiopathic scoliosis (AIS) were enrolled. An isokinetic back system in combination with quantitative surface EMG was used to evaluate the dominant and nondominant PSM activities by analyzing the root mean square (RMS) during isokinetic extension and flexion exercise at velocities of 30 degree/s and 90 degree/s.Significantly higher RMS of EMG were found in the dominant medial and lateral PSM of the lumbar region than the non-dominant muscles in the healthy control group and in those with AIS with smaller curves (20 degrees) during isokinetic flexion and extension exercises. In AIS patients with larger curves (20 to 50 degrees), shifting of muscle activities from the dominant to the non-dominant side occurred during isokinetic exercises, and the EMG activities of the thoracic muscle were significantly higher on the non-dominant (concave) side than on the dominant (convex) side.The bilateral PSM do not act symmetrically during isokinetic back exercises. The dominant lumbar PSM supply the major action in healthy subjects and patients with small curve scoliosis. For larger curve scoliosis, compensated muscle activity is needed in the midback when doing resistance exercises. More midback protection may be needed by scoliotic subjects with large curves during resistance exercise.

Body sway increases with age. The purpose of this study was to obtain baseline data and the characteristics of balance performance in different age groups for balance strategy management.Healthy individuals (n = 107) were divided into young, middle-aged, and elderly groups, and assessed by computerized dynamic posturography (CDP) on a Smart Balance Master. The 6 subtests in the sensory organization tests (SOT) for the CDP were as follows: subtest 1, eyes open, fixed support platform; subtest 2, eyes closed, fixed platform; subtest 3, eyes open, fixed platform; subtest 4, eyes open, swaying platform; subtest 5, eyes closed, swaying platform; subtest 6, swaying visual surround, swaying platform. Motor balance control tests included the limit of stability (LOS) test at 75% of LOS in 8 directions and the left/right and forward/backward rhythmic weight shift (RWS) test.In the SOT, the elderly group demonstrated significantly lower average stability and maximal stability scores in subtests 4-6. This group also demonstrated a relatively lower average percentage of ankle strategy in subtests 4-6. In the motor control tests, the elderly group demonstrated a significantly higher overall reactive time and lower overall directional control in the LOS test, lower on-axis velocity during the forward/backward and left/right motor control test and a lower average percentage of forward/backward directional control in the RWS test.The elderly had a higher degree of postural imbalance and used hip strategy to a greater extent to maintain their balance, especially when standing on a swaying support surface in the absence of visual surround or with conflicted visual surround. The elderly required a longer reaction time and demonstrated lower directional control in balance performance.