ABSTRACT
Objective An X-shaped cushioning insole with variable stiffness was designed to explore its effects on plantar pressure and internal stress of diabetic patients with toe amputation. Methods Based on CT images, the feet-calf finite element model of diabetic patients with toe amputation was established, and the insole was divided into different areas according to distribution characteristics of the planter pressure. The three-dimensional (3D) printed cushioning insole with an X-shaped sandwich structure was designed. The modulus of the sandwichstructure was changed by changing thickness of the sandwich structure panel. For simulation analysis, the divided area was filled with the X-shaped sandwich structure with different modulus. Results The peak plantar pressure of diabetic patients with toe amputation was in calcaneal region, and the combined insoles with 1. 2 mpanel thickness in toe area, 1. 4 mm panel thickness in metatarsal area, 2. 0 mm panel thickness in middle area and 1. 6 mm panel thickness in heel area had the best decompression effect. Compared with bare feet, the peak pressure in heel area of the insole, the peak pressure in phalangeal head area and the stress in plantar softissues were reduced by 40. 18% , 31. 7% , and 50. 44% , respectively. Conclusions The 3D printed insoles with variable stiffness can effectively reduce surface pressure and internal stress of the sole and reduce probability of the 2nd toe amputation
ABSTRACT
ObjectiveTo analyze the characteristics of plantar pressure of diabetic patients during gait cycle, and to design a offloading insole with variable stiffness. MethodsThe plantar pressure experiment was carried out and a database including 157 subjects was established. The differences of plantar pressure distribution were analyzed among diabetic patients with and without peripheral neuropathy, and healthy people. The insole pressure area was divided, and porous units were filled in different insole areas according to the pressure gradient. The fed-calf-insole finite element model of diabetic patients was constructed. The simulation analysis of different insole schemes was carried out under the conditions of push-off, footheel-strike and dynamic neutrality posture, and to explore the most reasonable insole stiffness design. ResultsCompared with the healthy group, the percentage of peak pressure and high pressure in the left and right heel areas of diabetic neuropathy patients showed a decreasing trend, in which the left peak pressure was significantly reduced by 11% (P = 0.026) and the percentage of high pressure was significantly reduced by 9.8% (P = 0.02). When the porous elements of 2.5 MPa and 1.9 MPa were used in the high pressure area of the insole metatarsal and high pressure area of the heel, the peak plantar pressure of footheel-strike, dynamic neutral and push-off was reduced by 42.4%, 27.4% and 26.4%, and the peak stress of the soft tissue was reduced by 49.8%, 43.6% and 25.1%, respectively. ConclusionThere is a higher risk of ulcer in the metatarsal region than in the heel region for diabetic patients. The variable stiffness insoles based on the optimization of plantar pressure and internal stress under multi-posture can effectively reduce the peak pressure of plantar and peak stress of soft tissue during walking, which provides a reference for the design of variable stiffness insoles.
ABSTRACT
OBJECTIVE To provide emp irical evidence for relevant decision makers in China to formulate and improve policies related to children ’s medicine use . METHODS Based on the purchase data （Jul. 2016-Jun. 2019）of 18 tertiary children ’s hospitals，the availability of medicines included in the 7th edition of WHO Model List of Essential Medicines for Children （WHO EMLc）and their influential factors were investigated according to standard medicine investigation method recommended by the WHO and Health Action International . RESULTS A totally 189 active ingredients listed in the 7th edition of WHO EMLc were available at 18 tertiary children ’s hospitals in China ，which referred to 229 medicines. The availability of Budesonide inhalation suspension，oral rehydration salt ，Immunoglobulin for injection and Water for injection was 100%. In each quarter from Jul . 2016 to Jun . 2019，the availability of more than half of the medicines exceeded 50%，and the availability of the medicines remained basically stable in each quarter . The overall availability of cardiovascular system medicines and blood system medicines was the highest，while that of antiparasitic medicines and dermatology medicines was lower . There were 28 medicines（12.2%）that were not approved for use in children in China ，the use of which were off -label. The medicines which had been approved for children and which were included in national essential medicine list had a significantly higher availability （P＜0.05）. CONCLUSIONS The availability of essential medicines for children is generally better at tertiary children ’s hospitals in China . But the use of some essential medicines in children are off -label. In order to ensure the safety and the availability of essential medicines for children ，it is suggested to introduce China ’s essential medicines list for children ，to promote clinical trials in children for commonly used medicines，and to updete the drug manual in time .