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Background

Previous studies suggest that life satisfaction assessment using the Life Satisfaction checklist (LiSat-11) is a meaningful outcome measure and may play an important role in setting rehabilitation goals in patients with chronic pain. Until now, there was no Japanese version of this questionnaire, and the psychometric properties of the original version of the LiSat-11 have only been investigated using classical test theory approaches. The objective of the present study was to evaluate the psychometric properties of the LiSat-11-J using Rasch analysis in a sample of Japanese people with low back pain (LBP).

Methods

One hundred and two participants with LBP completed the LiSat-11-J. Concurrent Validity of the LiSat-11-J was investigated by examining the relationships between the LiSat-11-J and clinical valuable. Rasch analysis was used to assess targeting, category ordering, unidimensionality, person fit, internal consistency, and differential item functioning.

Results

The LiSat-11-J was significantly correlated with disability, pain-related catastrophizing, fear of movement, anxiety, and depression. The LiSat-11-J targeted the participants with low life satisfaction and had unidimensionality, good internal consistency, and good test-retest reliability. Responses to category 1 (“very dissatisfying”) and 2 (“dissatisfying”) were disordered. After collapsing these two categories into a single new category, targeting function and category order showed a little improvement.

Conclusion

The LiSat-11-J has unidimensionality, acceptable internal consistency, good test-retest reliability, and concurrent validity to the assessment of pain-related disability and psychological factors. However, targeting function and category order were not well. These two components showed improvement by rescoring category, but not sufficient. These results suggest that the LiSat-11-J is not well adequate to apply as an assessment tool of life satisfaction to the patients with LBP.  相似文献   
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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.

Key points

  • Collegiate baseball pitchers can generate the hip and knee joint torques on the pivot leg for accelerating the body forward.
  • Collegiate baseball pitchers can generate the hip and knee joint torques to control/stabilize the stride leg in order to increase momentum on the stride leg during the arm acceleration phase.
  • The kinematics of the 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.
  • Adolescent baseball pitchers cannot generate the hip and knee joint torques in the pivot and stride leg for transfer of the energy of trunk and the arm.
Key words: Pitching ball velocity, the open kinetic chain, joint moment, ground-reaction force, motion analysis  相似文献   
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Background

In daily clinical practice, it is essential to properly evaluate the postoperative sliding distance of various femoral head fixation devices (HFD) for trochanteric fractures. Although it is necessary to develop an accurate and reproducible method that is unaffected by inconsistent postoperative limb position on radiography, few studies have examined which method is optimal. Therefore, the purpose of this study is to prospectively compare the accuracy and reproducibility of our four original methods in the measurement of sliding distance of the HFD.

Methods

Radiographs of plastic simulated bone implanted with Japanese proximal femoral nail antirotation were taken in five limb postures: neutral, flexion, minute internal rotation, greater external rotation, and flexion with external rotation. Orthopedic surgeons performed five measurements of the sliding distance of the HFD in each of the flowing four methods: nail axis reference (NAR), modified NAR, inner edge reference, and nail tip reference. We also assessed two clinical cases by using these methods and evaluated the intraclass correlation coefficients.

Results

The measured values were consistent in the NAR method regardless of limb posture, with an even smaller error when using the modified NAR method. The standard deviation (SD) was high in the nail tip reference method and extremely low in the modified NAR method. In the two clinical cases, the SD was the lowest in the modified NAR method, similar to the results using plastic simulated bone. The intraclass correlation coefficients showed the highest value in the modified NAR method.

Conclusions

We conclude that the modified NAR method should be the most recommended based on its accuracy, reproducibility, and usefulness.  相似文献   
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