基于新型渐开线球形齿轮的蛇形机器人设计分析

提出一种基于新型渐开线球形齿轮的蛇形机器人模型。首先介绍了蛇形机器人的结构和工作原理,分析了3D打印渐开线球形齿轮的啮合特点,对由偏摆单元以及驱动单元组成的偏摆角度及位置实时可控的单骨节进行设计分析,再对5骨节的蛇形机器人位置坐标进行分析,最后对单骨节和蛇形机器人的运动进行仿真以及单骨节实物的运动模拟和实验,结果表明设计可行有效。

A correlative study between prevalence of chondromalacia patellae and sports injury in 4068 students

Objective: To study the prevalence of chondromalacia patella among college students and the correlation with sports injury. Methods: 354 students from gymnastic department and 429 from nongymnastic department with knee joint pain were selected. 184 students from gymnastic department and 342 from nongymnastic department were checked randomly by a surgeon. 77 patients (37 males, 40 females) from gymnastic department and 119 patients (62 males, 57 females) from nongymnastic department were diagnosed as chondromalacia patellae. The amount of exercise and the occurrence of sports injury were investigated in each student. All data were analyzed with SPSS 10.0 statistical software. Results: The prevalence of chondromalacia patella was 20.1% in female students and 11.6% in male students from gymnastic department, and 5.61% in female students and 4.92% in male students from nongymnastic department. The amount of exercise and the occurrence of sports injury to the knee joint in students from gymnastic department were greater than those from nongymnastic department. Conclusions: In both female and male students, the prevalence of chondromalacia patella is higher in gymnastic department than nongymnastic department. Sports injury is an important cause of chondromalacia patella.

Gait analysis of patients with knee osteoarthritis before and after Chinese massage treatment

The objective of this study was to evaluate the effectiveness of Chinese massage therapy in patients with knee osteoarthritis(OA) by measuring lower-limb gait parameters. We recruited 20 women with knee OA,who then underwent Chinese massage therapy three times per week for 2 weeks. The patients underwent gait evaluation using a six-camera infrared motion analysis system. They completed Western Ontario and Mc Master Universities Osteoarthritis Index questionnaires before and after treatment. We calculated the forward speed,step width,step length,total support time percentage,initial double support time percentage,and single support time percentage. We also measured the angles at the knee,hip,and ankle during the stance phase of walking. The results showed statistically significant mean differences in knee pain relief,alleviation of stiffness,and physical function enhancement after therapy(P < 0.05). The patients gained significantly faster gait speed,greater step width,and increased total support time percentage after the Chinese massage therapy(P < 0.05). There were no significant differences in the range of motion or initial contact angles of the knee,hip,or ankle during the stance phase of walking. We concluded that Chinese massage is a beneficial complementary treatment and an alternative therapy choice for patients with knee OA for short-term pain relief. Chinese massage may improve walking ability for these patients.

Effect of Tuina Exercise on Quadriceps Femoris Muscle Strength of Patients with Knee Osteoarthritis

Objective： To investigate the effect of Yi Jin Jing exercise on quadriceps femoris muscle strength of patients with knee osteoarthritis （KOA） and thus provide scientific basis for Yi Jin Jing intervention in KOA. Methods： A total of 90 cases with KOA were randomized into an observation group and a control group, 45 in each group. Those in the observation group conducted Yi Jin Jing exercise once a day; whereas those in the control group received no therapies at all. The therapeutic effects have been assessed after 8 weeks of observation. Results： After 8 weeks of observation, the isokinetic muscle strength of quadriceps femoris muscle in the treatment group was substantially improved, whereas there were no distinct changes of isokinetic muscle strength of quadriceps femoris muscle in the control group. Conclusion： Yi Jin Jing exercise can definitely improve the quadriceps femoris muscle strength of patients with KOA. It is therefore an effective intervention method for KOA.

Human hip joint center analysis for biomechanical design of a hip joint exoskeleton

We propose a new method for the customized design of hip exoskeletons based on the optimization of the humanmachine physical interface to improve user comfort. The approach is based on mechanisms designed to follow the natural trajectories of the human hip as the flexion angle varies during motion. The motions of the hip joint center with variation of the flexion angle were measured and the resulting trajectory was modeled. An exoskeleton mechanism capable to follow the hip center＇s movement was designed to cover the full motion ranges of flexion and abduction angles, and was adopted in a lower extremity assistive exoskeleton. The resulting design can reduce human-machine interaction forces by 24.1% and 76.0% during hip flexion and abduction, respectively, leading to a more ergonomic and comfortable-to-wear exoskeleton system. The humanexoskeleton model was analyzed to further validate the decrease of the hip joint internal force during hip joint flexion or abduction by applying the resulting design.

Effect of acupuncture plus exercise on pain and motor function in patients with knee osteoarthritis

Objective:To observe the effects of acupuncture combined with isokinetic eccentric exercise on pain and motor function in patients with knee osteoarthritis(KOA).Methods:Sixty-four patients with KOA were randomly divided into an observation group and a control group,with 32 cases in each group.The observation group received acupuncture and isokinetic eccentric exercise,and the control group received isokinetic eccentric exercise and oral intake of meloxicam tablets.Both groups were treated for 4 weeks.Before and after treatment,the visual analog scale(VAS)score,the lysholm knee scale(LKS)score,and the quadriceps peak torque(PT)were evaluated.Results:The total effective rate was 93.8%in the observation group,versus 81.3%in the control group.The difference between the two groups was statistically significant(P<0.05).After treatment,the VAS scores of the two groups were lower than those before the treatment;both LKS score and quadriceps PT were higher than those before treatment,and the differences were statistically significant(all P<0.05).The VAS score,LKS score and quadriceps PT(angular velocity was 60%)of the observation group were significantly different from those of the control group(all P<0.05).Conclusion:Acupuncture plus isokinetic eccentric exercise is effective in treating KOA.The combined treatment can reduce the pain of KOA patients,improve joint function,strengthen quadriceps,improve joint stability,and its curative effect is better than isokinetic eccentric exercise plus oral intake of meloxicam tablets.

Extraarticular bony ankylosis in a child with supracondy- lar fracture of humerus

Myositis ossificans is defined as formation of bone at the site of injured muscle. It is one of the rare complications of supracondylar fracture of humerus in children. Myositis mass usually develops on the anterior aspect in the brachialis muscle and produces restriction of range of motion, but complete ankylosis is rare. To the best of our knowledge, this is the first case to be reported in the literature as a consequence of myositis ossificans traumatica. In this case, a six-year-old child presented to the casualtydepartment with pain in the right elbow after a fail on outstretched hand during play. After surgical excision through the anterior approach, the child had no symptoms referable to the elbow and a residual flexion deformity of 15 degrees with further painless flexion up to l00 degrees at last followup of one year after surgery.