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Context: Excessive knee valgus on landing can cause anterior cruciate ligament injury. Therefore, knee valgus alignment may show characteristic energy absorption patterns during landings with lateral movement that impose greater impact forces on the knee joint compared with landings in other alignments. Objective: To investigate the energy absorption strategy in lower-extremities during side steps in females with knee valgus alignment. Design: Controlled laboratory study. Setting: University research laboratory. Participants: A total of 34 female college students participated in this experiment. Interventions: Participants performed single-leg drop vertical jump and side steps. All participants were divided into valgus (n = 13), neutral (n = 9), and varus (n = 12) groups according to knee position during landing in single-leg drop vertical jumps. Main Outcome Measures: Lower-extremity joint angles, moments, and negative works were calculated during landing in side steps, and 1-way analysis of variance and post hoc tests were used to determine between-group differences. Results: Negative works of hip extensors, knee abductors, and ankle plantar flexors during landing in side steps were significantly smaller in the valgus than in the varus group; however, negative work of the knee extensors was significantly greater in the valgus group than in varus group. Conclusions: The findings of this study indicated that landing with knee valgus induced the characteristic energy absorption strategy in the lower-extremity. Knee extensors contributed more to energy absorption when landing in knee valgus than in knee varus alignment. Learning to land in knee varus alignment might reduce the impact on the knee joint by increasing the energy absorption capacities of hip extensors, knee abductors, and ankle plantar flexors. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of foot progression angle on the reduction in knee adduction moment caused by a lateral wedged insole during walking. Twenty healthy, young volunteers walked 10 m at their comfortable velocity wearing a lateral wedged insole or control flat insole in 3 foot progression angle conditions: natural, toe-out, and toe-in. A 3-dimensional rigid link model was used to calculate the external knee adduction moment, the moment arm of ground reaction force to knee joint center, and the reduction ratio of knee adduction moment and moment arm. The result indicated that the toe-out condition and lateral wedged insole decreased the knee adduction moment in the whole stance phase. The reduction ratio of the knee adduction moment and the moment arm exhibited a close relationship. Lateral wedged insoles decreased the knee adduction moment in various foot progression angle conditions due to decrease of the moment arm of the ground reaction force. Moreover, the knee adduction moment during the toe-out gait with lateral wedged insole was the smallest due to the synergistic effect of the lateral wedged insole and foot progression angle. Lateral wedged insoles may be a valid intervention for patients with knee osteoarthritis regardless of the foot progression angle. [ABSTRACT FROM AUTHOR]

BACKGROUND: The prevalence of radiographic knee osteoarthritis (OA) in Japan is high, with an estimated 25,300,000 affected individuals. OBJECTIVE: The purpose of this study was to clarify the characteristics of knee osteoarthritis by comparing differences between patients with knee osteoarthritis and healthy elderly individuals with respect to alignment of the pelvis and lower extremities and range of motion. METHODS: Twenty-six women (13 with medial knee osteoarthritis and 13 healthy elderly) participated in this study. Pelvic tilt, knee extension angle, femoro-tibial angle, quadriceps angle, navicular drop, and leg-heel alignment were measured. In addition, the range of motion was measured at the hip, knee, and ankle joints. RESULTS: Patients with knee osteoarthritis showed a posterior pelvic tilt, knee flexion, varus, and foot pronation alignment compared to healthy subjects. The range of motion for hip extension, adduction, knee flexion, extension, and ankle dorsiflexion was significantly smaller while the range of motion for eversion was significantly larger in the knee osteoarthritis group. CONCLUSION: People with medial knee OA have different static alignment and ROM compared to those without knee OA. The results clarify the comprehensive characteristics of the pelvis and lower extremities in knee osteoarthritis. [ABSTRACT FROM AUTHOR]

A male whale shark (Rhincodon typus) has been kept in captivity at the Okinawa Churaumi Aquarium, Japan, for 23 years, providing a rare opportunity to observe sexual maturation of a male. In 2012, when the individual was 8.5 m in total length (TL), the claspers began to elongate, and the distal ends of the claspers changed into cauliflower-shaped forms. These morphological changes in the claspers were completed in 11 months. Plasma concentrations of sex hormones (testosterone and progesterone) increased in association with clasper elongation. After elongation, additional movements, including the adduction and crossing of claspers, were displayed, and a whitish fluid, which may have been semen, was discharged through the clasper grooves, indicating that the male was functionally mature after clasper elongation. These observations indicate that this captive whale shark reached maturity when it was 8.5 m TL and over 25 years in age. This size at maturity is consistent with observations in the wild. However, maturity in this individual captive animal may have occurred later than has been previously reported in nature. [ABSTRACT FROM AUTHOR]

Background: During pitching, an overloaded joint reaction force exerted on the shoulder and excessive shoulder horizontal abduction at ball release are considered risk factors causing anterior shoulder pain for young baseball pitchers. Hypothesis/Purpose: The first aim was to examine the relationship between shoulder horizontal abduction position and force on the shoulder at ball release. The second was to identify the relative rotational position of the shoulder and the range of shoulder motion at ball release that minimize force on the shoulder. It was hypothesized that the amount of force on the shoulder would be exacerbated by excessive shoulder horizontal abduction. Study Design: Descriptive laboratory study. Methods: Participants were 183 adolescent baseball pitchers (mean ± SD age, 15.5 ± 1.2 years) without shoulder/elbow problems. Each pitcher threw 5 fastballs to a catcher behind a home plate. The kinematics and kinetics of the throwing shoulder during fastball pitching were calculated with 3-dimensional measurements from 36 reflective markers. In data analysis, the correlations were calculated between the relative rotational positions of the shoulder (abduction, horizontal adduction-abduction) and the forces on the shoulder (anterior-posterior, proximal, and superior-inferior) at ball release. Subsequently, the specific rotational position and range of motion of the shoulder at ball release that minimized forces on the shoulder were determined. Results: Statistically significant correlations were identified between the magnitude of superior-inferior force on the shoulder and shoulder abduction position (R2 = 0.44, P < .001) as well as between the magnitude of anterior-posterior force on the shoulder and shoulder horizontal adduction-abduction position (R2 = 0.72, P < .001). Minimal anterior-posterior and superior-inferior forces were obtained with a combination of 80.6° of shoulder abduction and 10.7° of shoulder horizontal adduction. Any deviation >5° from this position significantly increased the anterior-posterior and superior-inferior forces on the shoulder. Conclusion: Increasing shoulder horizontal abduction position significantly increased the magnitude of anterior force on the shoulder at ball release. The combination of 80.6° of shoulder abduction and 10.7° of horizontal shoulder adduction minimized the shear forces on the shoulder at this point. Clinical Relevance: The present data can be useful for screening pitching technique to prevent shoulder pain and injury with motion capture assessment. [ABSTRACT FROM AUTHOR]

The purpose of this study was to clarify the differences between adolescent and collegiate baseball pitchers in the kinematic and kinetic profiles of the trunk and lower limbs during the pitching motion. The subjects were thirty-two adolescent baseball pitchers aged 12-15 years (APG) and thirty collegiate baseball pitchers aged 18-22 years (CPG). Three-dimensional motion analysis with a comprehensive lower-extremity model was used to evaluate kinematic and kinetic parameters during baseball pitching. The ground reaction forces (GRFs) of the pivot and stride legs during pitching were determined using two multicomponent force plates. The joint torques of hip, knee, and ankle were calculated by the inverse-dynamics computation of musculoskeletal human models using motion-capture data. To eliminate any effect of variation in body size, kinetic and GRFs data were normalized by dividing them by body mass. The velocity of a pitched ball was significantly higher (p < 0.01) in CPG (35.2 ± 1.9 m⋅s-1) than in the APG (30.7 ± 2.7 m⋅s-1). Most kinematic parameters for the lower limbs were similar between the CPG and the APG. Maximum Fy (toward the throwing direction) on the pivot leg and Fy and resultant forces on the stride leg at ball release were significantly greater in the CPG than in the APG (p < 0.05). Hip and knee joint torques on the lower limbs were significantly greater in the CPG than in the APG (p < 0.05). The present study indicates that the kinematics of lower limbs during baseball pitching are similar between adolescent and collegiate pitchers, but the momentum of the lower limbs during pitching is lower in adolescent pitchers than in collegiate ones, even when the difference in body mass is considered. [ABSTRACT FROM AUTHOR]

This study investigated the relationships between thumb muscle activity and thumb operating tasks on a smartphone touch screen with one-hand posture. Six muscles in the right thumb and forearm were targeted in this study, namely adductor pollicis, flexor pollicis brevis, abductor pollicis brevis (APB), abductor pollicis longus, first dorsal interosseous (FDI) and extensor digitorum. The performance measures showed that the thumb developed fatigue rapidly when tapping on smaller buttons (diameter: 9 mm compared with 3 mm), and moved more slowly in flexion–extension than in adduction–abduction orientation. Meanwhile, the electromyography and perceived exertion values of FDI significantly increased in small button and flexion–extension tasks, while those of APB were greater in the adduction–abduction task. This study reveals that muscle effort among thumb muscles on a touch screen smartphone varies according to the task, and suggests that the use of small touch buttons should be minimised for better thumb performance. Practitioner Summary:Through measurements of electromyography, thumb performance and perceived exertion, this study reveals that demand on FDI increases when the thumb taps small buttons and in flexion–extension orientation, but that demand on APB increases in adduction–abduction orientation. The decreased thumb performance with small buttons is attributed to a combination of smaller targets and increased demand on FDI. [ABSTRACT FROM PUBLISHER]

Objective. Measurements of knee joint movement in gait analysis may result in large errors caused by misplacement of reflective markers by the testers. To properly understand the measurement results, it is important to guarantee the reliability of the measurement method used for the purpose.The aim of this study was to confirm the interrater reproducibility of a measurement method with a rigid marker set (RMS). Methods. The study subjects were four healthy adults, and the testers were three physical therapists.The interrater reproducibility of themeasurements was verified by using the coefficient ofmultiple correlations (CMCs) and the standard error of measurement (SEM). Results. The average CMCs values of 4 subjects in knee joint movement at the stance phase were greater than 0.8, and the average SEM values of 4 subjects in knee joint movement at the stance phase were also relatively good (maximumerror: 2.42°). Conclusion. Based on these results, themeasurementmethod with estimation of anatomical landmarks using theRMScan prevent misplacement during attachment of the reflectivemarkers, as long as the testers have sufficient experience in attaching reflective markers. [ABSTRACT FROM AUTHOR]

Abstract: A normalized cDNA library was constructed from the adductor muscle of M. yessoensis and acquired 4595 high quality expressed sequence tags (ESTs). After clustering and assembly of the ESTs, 3061 unigenes containing 654 contigs and 2407 singletons were identified. The contig length ranged from 266bp to 2364bp and the average length of these contigs was 544bp. Blastx nonredundant protein database analysis showed that 1522 unigenes had significant homology to known genes (E value ≤10−5). By comparing to Clusters of Orthologous Groups (COG) categories, 460 unigenes were annotated (E value ≤10−10). Using Kyoto Encyclopedia of Genes and Genomes (KEGG), 345 of 3061 unigenes were assigned into 103 pathways (E value ≤10−5). For InterProScan searches, 1237 unigenes were annotated containing 727 different types of protein domains. 941 of the 1237 unigenes were annotated for Gene Ontology (GO) classification using Uniprot2GO associations in any category (biological, cellular, and molecular). By sequences comparability and analysis of Blastx NCBI nonredundant protein database and KEGG, 66 unigenes were identified that may be involved in genetic information processing based on the known knowledge. The study provides a material basis as useful information for the genomic analysis of shellfish. [ABSTRACT FROM AUTHOR]

Background: An increase in the knee adduction moment is one of the risk factors of medial knee osteoarthritis. This study examined the relationship between knee adduction moment and self-reported pain and disability. We also investigated the influence of pain on the relationships between knee adduction moment and gait performance and disability. Methods: Thirty-eight Japanese women with medial knee osteoarthritis participated in this study (66.37years (41–79years)). Gait analysis involved the measurement of the external knee adduction moment impulse in the stance duration and during 3 subdivisions of stance. The total, pain and stiffness, and physical function Japanese Knee Osteoarthritis Measure scores were determined. Findings: The pain and stiffness, physical function, and total scores were positively correlated with the knee adduction moment impulses in the stance duration, and initial and second double support interval, and single limb support interval. The knee adduction moment impulse during the stance duration was related to the pain and stiffness subscale and gait velocity. The pain and stiffness subscale was related to the physical function subscale. Interpretation: Our results suggest that increasing in the knee adduction moment impulse, a proxy for loading on the medial compartment of the knee, is related to increased pain during weight-bearing activities such as walking, thereby restricting walking performance and causing disability by reducing gait velocity. Thus, the reduction in the knee adduction moment impulse during gait may result in pain relief and may serve as a conservative treatment option with disease-modifying potential. [Copyright &y& Elsevier]

We measured the Joint Position Sense (JPS) in adduction angle in patients with ankle lateral ligament injury, using our original Goniometer foot plate. The injury group comprised 15 patients with chronic ankle lateral ligament injury, and the JPS was measured as preoperative assessment. For the patients, the preoperatively assessed side was defined as the injury side, while the other side was defined as the non-injury side. We recorded the Absolute Error (AE) between target angle and replicated angle, and compared with the control group (20 healthy volunteers). Statistically significant differences were noted in the AE between the injury side and control group (p<0.05). This suggests that the patients with ankle lateral ligament injury exhibit a JPS deficit in adduction angle. [ABSTRACT FROM AUTHOR]