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.

The aim of this study was to investigate the risk of fracture and the difference between sexes from a nationwide database of fracture risk among children aged 4-17 years with or without attention deficit hyperactivity disorder (ADHD, ICD-9-CD codes 314). The Longitudinal Health Insurance Database (LHID 2000) was used to analyze fracture characteristics of children from the National Health Insurance that covered 96.1% of the Taiwanese population (N=21.4 million). A total of 7200 ADHD children aged between 4 and 17 years whose diagnosis had been confirmed in at least three outpatient clinics between 1 January 2000 and 31 December 2009 were included, and a cohort of 36 000 children without ADHD matched for age, sex, and urbanization was recruited for analysis. The incidence rate of fractures in ADHD children was 21.0 (95% confidence interval=19.4-22.7) per 1000 person-years, significantly (P<0.001) higher than 15.0 (95% confidence interval=14.4-15.6) in non-ADHDs. After adjusting by age, sex, urbanization level, and geographic region, the statistically significant (P<0.001) hazard ratios (HR) of fracture for ADHD children compared with non-ADHD children included 1.62 in girls and 1.38 in boys, 1.53 in the skull, neck, and trunk (ICD-9-CM 800-809), 1.28 in the upper extremity (ICD-9-CM 810-819), and 1.84 in the lower extremity (ICD-9-CM 820-829). The HR also (P<0.001) increased significantly in all age groups, including 1.35 in 4-6, 1.37 in 7-9, and 1.54 in 10-17 years. ADHD should be listed among risk factors of children's fractures in each sex, all age groups, and all body areas that the parents, teachers, caregivers of ADHD children, and pediatric orthopedists should be aware of. Besides, ADHD girls were more affected than ADHD boys, especially after 10 years of age, whereas the adjusted HR was the highest in the lower extremities. Nationwide analysis matched for age and sex showed that ADHD should be considered the risk factor of children's fracture, especially for girls older than 10 years of age.

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.

PurposeTo mitigate the risk of poor wound healing and of infection associated with the open repair of Achilles tendon midsubstance ruptures, minimally invasive techniques have been developed. We report our preliminary results after reviewing our “jigless knotless internal brace technique.”MethodsPatients were placed in prone position and a transverse 3-cm incision was made proximal to the palpable ruptured end. The proximal ruptured end was pulled out, gently debrided, and sutured using Krackow locking loops. Percutaneous sutures were crisscrossed through the distal tendon stump and looped around the Krackow sutures over the proximal stump. The ipsilateral Krackow sutures and the contralateral crisscrossed sutures were subcutaneously passed through two mini-incisions over the posterior calcaneus tuberosity and seated at the tuberosity with two 4.5-mm knotless suture anchors. All patients underwent the same post-operative rehabilitation protocol and regular follow-ups for at least 1 year.ResultsWe recruited 10 patients (mean age, 37.3 years) who scored 100 points on the American Orthopaedic Foot and Ankle Society (AOFAS) scale, and who returned to their preoperative exercise levels 1-year post-operatively with no complications.ConclusionOur method is simple, effective, and requires no special tools. It might be a reliable option for Achilles tendon repair.Level of evidenceIII

PurposeThe purpose of this study was to analyze the variation in measuring the lateral center edge angle of Wiberg (LCEA) using the lateral edge of the sourcil (LCEA-S) compared to the lateral edge of the acetabulum (LCEA-E), and to correlate these measurements with three-dimensional computed tomography (3D-CT)-based analysis of the femoroacetabular articulation.MethodsA retrospective analysis was performed on 24 patients (45 hips) treated for hip dysplasia at a single institution. All patients were required to have an anteroposterior (AP) pelvis radiograph and pelvic CT. LCEA-S and LCEA-E measurements were calculated from radiographs. Axial CT images were processed to standardize pelvic orientation and calculate the LCEA at three points (posterior, central, anterior) along the acetabular edge. Correlation analysis was used to evaluate radiographic and CT measures.ResultsEight males and 16 females with an average age of 14.6 years were included. The LCEA-S (16.5° ± 2.0°) was found to be significantly less than the LCEA-E (26.0° ± 2.0°) (p < 0.001). The LCEA-S had the greatest correlation with the central measurement on the 3D-CT (rs = 0.893; p < 0.001). The LCEA-E had the greatest correlation with the anterior measurement on the 3D-CT (r = 0.834; p < 0.001).ConclusionsThe LCEA can change significantly depending on the bony landmark used to define the lateral edge of the femoroacetabular articulation. The edge of the sourcil most closely correlates with the central weight-bearing portion of the articular surface on the 3D-CT and should be used to define the LCEA when treating patients with hip dysplasia.Level of evidenceLevel III, retrospective comparison study.