An improvement of current hypercube pooling PCR tests for SARS-CoV-2 detection.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic can be effectively controlled by rapid and accurate identification of SARS-CoV-2-infected cases through large-scale screening. Hypercube pooling polymerase chain reaction (PCR) is frequently used as a pooling technique because of its high speed and efficiency. We attempted to implement the hypercube pooling strategy and found it had a large quantization effect. This raised two questions: is hypercube pooling with edge = 3 actually the optimal strategy? If not, what is the best edge and dimension? We used a C++ program to calculate the expected number of PCR tests per patient for different values of prevalence, edge, and dimension. The results showed that every edge had a best performance range. Then, using C++ again, we created a program to calculate the optimal edge and dimension required for pooling samples when entering prevalence into our program. Our program will be provided as freeware in the hope that it can help governments fight the SARS-CoV-2 pandemic.

Mathematical model of distal radius orientation.

Distal radius orientation is important in evaluating Colles' fracture. In most cases, the wrist was protected by a bandage, splint, or cast. Therefore, it was difficult for the radiology technician to take perfect anteroposterior and lateral view radiographs. In this study, we build a mathematical model and calculate the pronation angle needed to produce dorsal tilt, which is a volar tilt in a perfect lateral view radiograph. The formulas are all incorporated into Excel to facilitate usage.

Best-Compromise Control Strategy Between Mechanical Energy Expenditure and Foot Clearance for Obstacle-Crossing in Older Adults: Effects of Tai-Chi Chuan Practice.

Background: Obstacle-crossing increases the risk of falls in older people. This study aimed to identify the effects of long-term Tai-Chi Chuan (TCC) practice on the control strategies for obstacle-crossing in older people. Methods: A multi-objective optimal control technique with measured gait data was used to identify the control strategies adopted by 15 long-term TCC practitioners and 15 healthy controls when crossing obstacles of different heights, in terms of the best-compromise weighting sets for the conflicting objectives of minimizing energy expenditure and maximizing the toe-obstacle and heel-obstacle clearances. Results and Conclusions: The long-term TCC older practitioners adopted a best-compromise control strategy similar to those adopted by young adults, with greater weightings on the minimization of the mechanical energy expenditure and smaller weightings on foot-clearance as compared to non-TCC controls (TCC: 0.72, 0.14, 0.14; Control: 0.55, 0.225, 0.225). This strategy enabled the long-term TCC older practitioners to cross obstacles with significantly greater leading-toe clearances but with relatively less mechanical energy expenditure. With the current approach, further simulations of obstacle-crossing mechanics with a given weighting set will be useful for answering clinically relevant what-if questions, such as what abilities would be needed if the non-TCC older people were to cross obstacles using the crossing strategy of the TCC people.

Cervical Spine Pathology Increases the Risk of Rotator Cuff Tear: A Population-Based Cohort Study.

BACKGROUND: Patients with cervical radiculopathy typically present with shoulder pain and weakness; these symptoms are similar to those of rotator cuff disease. Studies investigating cervical spine pathology (CSP) as an independent risk factor for rotator cuff tear (RCT) are lacking in the literature. PURPOSE: To investigate the risk of RCT among patients with CSP who have undergone cervical diskectomy (CD) and to determine whether CD reduces this risk. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The authors queried the Taiwan National Health Insurance Research Database for patients diagnosed with CSP between 2004 and 2008 and followed up until the end of 2010. A control cohort comprised patients without CSP who were age- and sex-matched in a 4-to-1 ratio with patients with CSP through propensity score matching. A Cox multivariate proportional hazards model was applied to analyze the risk factors for RCT. After adjustment for confounders, the authors calculated the hazard ratio (HR) and adjusted HR (aHR) between the study and control cohorts. The effects of CD on the risk of RCT were also analyzed. RESULTS: The study included 3245 patients and 12,980 matched controls. A higher RCT incidence rate was found in the CSP cohort, with an aHR of 1.52 (95% CI, 1.22-1.89; P < .001). Patients with CSP who underwent CD had a risk of RCT similar to that of the controls, with an aHR of 1.65 (95% CI, 0.90-3.03; P > .05). CONCLUSION: Patients with CSP had a 1.52-fold higher risk of RCT than healthy controls. Patients with CSP with CD did not have a high risk of RCT, possibly indicating a protective effect of diskectomy against RCT.

Hyperlipidemia Is a Risk Factor of Adhesive Capsulitis: Real-World Evidence Using the Taiwanese National Health Insurance Research Database.

BACKGROUND: Patients with adhesive capsulitis are evaluated for pain and progressive contracture of the glenohumeral joint. Whether endocrine, immune, or inflammatory processes are involved in its definite pathogenesis is still under debate. Some cross-sectional studies with a small sample size have noted that hyperlipidemia is a possible risk factor for frozen shoulders. PURPOSE/HYPOTHESIS: The purpose was to conduct a longitudinal population-based study to investigate the risk of adhesive capsulitis among patients with hyperlipidemia. It was hypothesized that patients with hyperlipidemia would have a higher risk of adhesive capsulitis and that the use of statin drugs could reduce the rate. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Using data from the National Health Insurance Research Database (NHIRD) of Taiwan, the authors obtained the records of patients with hyperlipidemia who received a diagnosis between 2004 and 2005 and were followed up until the end of 2010. The control cohort comprised age- and sex-matched patients without hyperlipidemia. Propensity score matching was performed for the other comorbidities. A Cox multivariate proportional hazards model was applied to analyze the risk factors of adhesive capsulitis. The hazard ratio (HR) and adjusted HR were estimated between the study and control cohorts after adjustment for confounders. The effects of statin use on adhesive capsulitis risk were also analyzed. RESULTS: The NHIRD records of 28,748 patients and 114,992 propensity score-matched controls were evaluated. A higher incidence rate of adhesive capsulitis was revealed in the hyperlipidemia cohort, with a crude HR of 1.70 (95% CI, 1.61-1.79; P < .001) and adjusted HR of 1.50 (95% CI, 1.41-1.59; P < .001). Patients with hyperlipidemia who used a statin still had higher crude and adjusted HRs compared with controls. Statin use did not exert protective effects on patients with hyperlipidemia. CONCLUSION: Patients with hyperlipidemia had a 1.5-fold higher risk of adhesive capsulitis than did healthy controls. Statin use did not provide protection against adhesive capsulitis in patients with hyperlipidemia.

Developing a Delphi-Based Comprehensive Core Set from the International Classification of Functioning, Disability, and Health Framework for the Rehabilitation of Patients with Burn Injuries.

Burn injuries cause disability and functional limitations in daily living. In a 2015 fire explosion in Taiwan, 499 young people sustained burn injuries. The construction of an effective and comprehensive rehabilitation program that enables patients to regain their previous function is imperative. The International Classification of Functioning, Disability, and Health (ICF) includes multiple dimensions that can contribute to meeting this goal. An ICF core set was developed in this study for Taiwanese patients with burns. A consensus process using three rounds of the Delphi technique was employed. A multidisciplinary team of 30 experts from various institutions was formed. The questionnaire used in this study comprised 162 ICF second-level categories relevant to burn injuries. A 5-point Likert scale was used, and participants assigned a weight to the effect of each category on daily activities after burns. The consensus among ratings was assessed using Spearman's ρ and semi-interquartile range indices. The core set for post-acute SCI was developed from categories that attained a mean score of ≥4.0 in the third round of the Delphi exercise. The core ICF set contained 68 categories. Of these, 19 comprised the component of body functions, 5 comprised body structures, 37 comprised activities and participation, and 7 comprised environmental factors. This preliminary core set offers a comprehensive system for disability assessment and verification following burn injury. The core set provides information for effective rehabilitation strategy setting for patients with burns. Further feasibility and validation studies are required in the future.

Effects of Tai-Chi Chuan Practice on Patterns and Stability of Lower Limb Inter-Joint Coordination During Obstructed Gait in the Elderly.

Losing balance or tripping during obstacle-crossing is one of the most frequent causes of falls in the elderly. As a low speed, low impact exercise, Tai Chi Chuan (TCC) can be promising in helping the elderly develop strategies for improved balance, inter-joint coordination, and end-point control during obstacle-crossing. This study investigates the effects of TCC training on the patterns and variability of the lower-limb inter-joint coordination during obstacle-crossing in the elderly. Fifteen older TCC practitioners and 15 healthy controls crossed obstacles of three different heights, while sagittal angles ( x ) and angular velocities ( x ' ) of the hips, knees and ankles were measured and their phase angles obtained. The continuous relative phases (CRP) of the hip-knee and knee-ankle coordination were also calculated. The standard deviations of the CRP curve points were averaged to obtain deviation phase (DP) values for the stance and swing phases. The TCC group was found to cross obstacles with increased leading and trailing toe-clearances with unaltered CRP values when the swing toe was above the obstacle. Long-term TCC training altered the patterns and magnitudes of the CRPs primarily over double-limb support and significantly reduced the variabilities of leading knee-ankle and trailing hip-knee and knee-ankle CRP curves over the crossing cycle, regardless of obstacle height. The current results suggest that long-term TCC practice was helpful for a crossing strategy with significantly increased foot-obstacle clearances and reduced variability of the way the motions of the lower limb joints are coordinated during obstacle-crossing. These benefits may be explained by the long-lasting effects of continuous practice of the slow movement patterns emphasizing between-limb transfer of body weight in TCC.

Arthroscopy-Assisted Corrective Osteotomy, Reduction, Internal Fixation and Strut Allograft Augmentation for Tibial Plateau Malunion or Nonunion.

PURPOSE: The purpose of this study was to present the results of arthroscopy-assisted corrective osteotomy (AACO), reduction, internal fixation, and strut allograft augmentation for tibial plateau malunion or nonunion. METHODS: Fifty-eight patients, mean age 49 ± 11.9 years old, with tibial plateau malunion (n = 44) or nonunion (n = 14), were included in this study. There were 19 Schatzker type II fractures (32.7%), 2 type III fractures (3.4%), 7 type IV fractures (12%), 20 type V fractures (34.5%), and 10 type VI fractures (17.2%). The mean follow-up period was 46.2 ± 17.6 months. Clinical and radiologic outcomes were scored by the Rasmussen system. Articular depression was measured from computed tomography. Secondary osteoarthritis was diagnosed when radiographs showed a narrowed joint space in the injured knee at follow-up. RESULTS: Mean clinical score improved from 15.4 ± 3.9 (pre-revision) to 23.2 ± 4.5 (post-revision). Mean radiologic score improved from 7.7 ± 2.5 (pre-revision) to 12.0 ± 3.9 (post-revision). Fifty-six fractures achieved successful union. The average union time was 19.6 ± 7.5 weeks. Post-revision, 81% had good or excellent clinical results and 62% had good or excellent radiological results. Secondary osteoarthritis (OA) was noted in 91% of all injured knees, where 25.8% were mild OA, 25.8 % were moderate OA, and 38% were severe OA. There were 6 cases of deep infection (10.3%) and 1 case of wound edge necrosis (1.7%). Five cases were converted to total knee replacement after the index surgery with an average period of 13.5 months (range 8-24 months). CONCLUSIONS: Arthroscopy-assisted corrective osteotomy, reduction, internal fixation, and strut allograft augmentation can restore tibial plateau malunion/nonunion with well-documented radiographic healing and good clinical outcomes.

Patients with Axial Spondyloarthritis Are at Risk of Developing Adhesive Capsulitis: Real-World Evidence Database Study in Taiwan.

Patients with axial spondyloarthritis (ax-SpA) present with inflammation invading the axial skeleton. Symptoms of ax-SpA interfere with patients' quality of life, and peripheral symptoms are also noted. Human leukocyte antigen B27 was associated with adhesive capsulitis. However, epidemiological studies investigating the associated incidence and risk factors for patients with ax-SpA with adhesive capsulitis are limited. The data of patients with ax-SpA were recorded during the 2004-2008 period and followed to the end of 2010. The control cohort comprised age- and sex-matched non-ax-SpA subjects. A Cox multivariate proportional hazards model was applied to analyze the risk factors for adhesive capsulitis. The hazard ratio (HR) and adjusted hazard ratio (aHR) were estimated between the study and control cohorts after confounders were adjusted for. Effects of sulfasalazine (SSZ), methotrexate (MTX), and hydroxychloroquine (HCQ) use on adhesive capsulitis risk were also analyzed. We enrolled 2859 patients with ax-SpA in the study cohort and 11,436 control subjects. A higher incidence of adhesive capsulitis was revealed in the ax-SpA cohort: The crude HR was 1.63 (95% CI, 1.24-2.13; p < 0.001), and the aHR was 1.54 (95% CI, 1.16-2.05; p = 0.002). For patients with ax-SpA using SSZ or HCQ, no difference in aHR was noted compared with control participants, but patients with ax-SpA treated with MTX had higher HR and aHR than controls. Patients with ax-SpA are at risk for adhesive capsulitis. When these patients receive SSZ or HCQ, the risk of adhesive capsulitis can be lowered compared with that of the control cohort.

Pedicle screw versus hybrid posterior instrumentation for dystrophic neurofibromatosis scoliosis.

Surgical management of severe rigid dystrophic neurofibromatosis (NF) scoliosis is technically demanding and produces varying results. In the current study, we reviewed 9 patients who were treated with combined anterior and posterior fusion using different types of instrumentation (i.e., pedicle screw, hybrid, and all-hook constructs) at our institute.Between September 2001 and July 2010 at our institute, 9 patients received anterior release/fusion and posterior fusion with different types of instrumentation, including a pedicle screw construct (n = 5), a hybrid construct (n = 3), and an all-hook construct (n = 1). We compared the pedicle screw group with the hybrid group to analyze differences in preoperative curve angle, immediate postoperative curve reduction, and latest follow-up curve angle.The mean follow-up period was 9.5 ±â€Š2.9 years. The average age at surgery was 10.3 ±â€Š3.9 years. The average preoperative scoliosis curve was 61.3 ±â€Š13.8°, and the average preoperative kyphosis curve was 39.8 ±â€Š19.7°. The average postoperative scoliosis and kyphosis curves were 29.7 ±â€Š10.7° and 21.0 ±â€Š13.5°, respectively. The most recent follow-up scoliosis and kyphosis curves were 43.4 ±â€Š17.3° and 29.4 ±â€Š18.9°, respectively. There was no significant difference in the correction angle (either coronal or sagittal), and there was no significant difference in the loss of sagittal correction between the pedicle screw construct group and the hybrid construct group. However, the patients who received pedicle screw constructs had significantly less loss of coronal correction (P < .05). Two patients with posterior instrumentation, one with an all-hook construct and the other with a hybrid construct, required surgical revision because of progression of deformity.It is difficult to intraoperatively correct dystrophic deformity and to maintain this correction after surgery. Combined anterior release/fusion and posterior fusion using either a pedicle screw construct or a hybrid construct provide similar curve corrections both sagittally and coronally. After long-term follow-up, sagittal correction was maintained with both constructs. However, patients treated with posterior instrumentation using pedicle screw constructs had significantly less loss of coronal correction.