Objective: This study aimed to predict the injury risk to attendants by simulating and analyzing the joint moment that occurs during wheelchair transportation for five different ramp ratios and five different velocities. Method: Three-dimensional musculoskeletal models and rigid structure of a standard wheelchair were developed using the AnyBody Modeling System. The ramp ratio was set to 1：6 (the steepest), 1：8, 1：10, 1：12, and 1：14 (the gentlest). The wheelchair speeds were set to 0.4, 0.5, 0.6, 0.7, and 0.8 m/s. Both the uphill and downhill movement conditions were investigated. Results: Most of the joint moments that occur in the wrist joint, elbow and shoulder while driving uphill increased or decreased proportionally to the slope and speed of the ramp. However, the external moment of the wrist occurring downhill was largely influenced by the slope, and the joint moment of the shoulder showed a dynamic pattern of change in the middle of the ramp in spite of constant driving speed. Conclusion The influence that occurs during deceleration while wheelchair driving on a ramp is primarily on the proximal shoulder joint, and the influence of the release control in the middle of driving primarily causes loads on the distal wrist and forearm. A high risk of damage exists because the moment change value of the load on the shoulder joint is relatively large and increases with inclination. The increase in wrist abduction moment for deceleration while driving downhill also suggests the possibility of damage.

Objective: To investigate the effect of gestational weight gain (GWG) on maternal and neonatal outcomes based on the Institute of Medicine (IOM) guidelines for twin pregnancies. Methods: This study included women with twin pregnancies who delivered at Seoul National University Bundang Hospital. Based on the weight gain per gestational week according to the 2009 IOM guidelines, the subjects were divided into the following 3 groups: inadequate, adequate, and excessive GWG. We compared the maternal and neonatal outcomes of each group. Results: A total of 1,738 twin pregnancies were included in our study. Of these cases, 881, 694, and 163 (50.7%, 39.9%, and 9.4%, respectively) twin pregnancies were categorized into the inadequate, adequate, and excessive GWG groups, respectively. In the inadequate GWG group, the risks of preterm birth <34 weeks (aOR, 2.33, 95% confidence interval [CI], 1.63–3.34) and delivering neonates who were small for gestational age (aOR, 1.92, 95% CI, 1.42–2.60) were increased, and the risk of preeclampsia (aOR, 0.49, 95% CI, 0.32–0.76) was decreased. The excessive GWG group had an increased risk of the neonates being large for gestational age (aOR, 1.79, 95% CI, 1.15–2.81). Conclusion The 2009 IOM recommendations for GWG can be applied to Korean women with twin pregnancies to help achieve optimal maternal and neonatal outcomes. However, more than half of the women were categorized as having inadequate weight gain according to the guidelines. Further studies should be performed to obtain Korean national references for GWG in twin pregnancies.

Objective: To investigate the effect of gestational weight gain (GWG) on maternal and neonatal outcomes based on the Institute of Medicine (IOM) guidelines for twin pregnancies. Methods: This study included women with twin pregnancies who delivered at Seoul National University Bundang Hospital. Based on the weight gain per gestational week according to the 2009 IOM guidelines, the subjects were divided into the following 3 groups: inadequate, adequate, and excessive GWG. We compared the maternal and neonatal outcomes of each group. Results: A total of 1,738 twin pregnancies were included in our study. Of these cases, 881, 694, and 163 (50.7%, 39.9%, and 9.4%, respectively) twin pregnancies were categorized into the inadequate, adequate, and excessive GWG groups, respectively. In the inadequate GWG group, the risks of preterm birth <34 weeks (aOR, 2.33, 95% confidence interval [CI], 1.63–3.34) and delivering neonates who were small for gestational age (aOR, 1.92, 95% CI, 1.42–2.60) were increased, and the risk of preeclampsia (aOR, 0.49, 95% CI, 0.32–0.76) was decreased. The excessive GWG group had an increased risk of the neonates being large for gestational age (aOR, 1.79, 95% CI, 1.15–2.81). Conclusion The 2009 IOM recommendations for GWG can be applied to Korean women with twin pregnancies to help achieve optimal maternal and neonatal outcomes. However, more than half of the women were categorized as having inadequate weight gain according to the guidelines. Further studies should be performed to obtain Korean national references for GWG in twin pregnancies.