ObjectiveTo investigate the effectiveness of repair procedure using biological mesh with Onlay-Reinforce technique in patients with perineal hernia. MethodsBetween January 2005 and December 2012, 9 patients with perineal hernia after laparoscopic abdominoperineal resection for rectal cancer (Miles operation) were treated. There were 3males and 6 females with a mean age of 70 years (range, 61-78 years). The disease duration was 1-9 months (mean, 4.5 months). The most beginning symptom was distending pain in perineal region, and then reducible mass was found without bowel incarceration. All patients underwent hernia repair using biological mesh with Onlay-Reinforce technique through original perineal incision. ResultsThe hernial size was 9.8-20.5 cm2 (mean, 16.0 cm2); the size of biological mesh was 58-80 cm2 (mean, 70.2 cm2); and the intraoperative blood loss was 10-80 mL (mean, 50.5 mL). All of the patients underwent repair operation successfully. The operation time was 45-90 minutes (mean, 60.6 minutes); and the hospitalization time was 4-7 days (mean, 5.9 days). One patient had urine retention, which was relieved after 7 days indwelling catheter. All the wounds healed by first intention without infection. The patients were followed up 14.5-60.7 months (mean, 37.8months). No chronic pain, obvious foreign body sensation, or hernia recurrence developed. ConclusionUse of biological mesh with Onlay-Reinforce technique for the repair of perineal hernia after Miles operation is safe and effective.
Robot-assisted fracture reduction usually involves fixing the proximal end of the fracture and driving the distal end of the fracture to the proximal end in a planned reduction path. In order to improve the accuracy and safety of reduction surgery, it is necessary to know the changing rule of muscle force and reduction force during reduction. Fracture reduction force was analyzed based on the muscle force of femoral. In this paper, a femoral skeletal muscle model named as PA-MTM was presented based on the four elements of skeletal muscle model. With this, pinnate angle of the skeletal muscle was considered, which had an effect on muscle force properties. Here, the muscle force of skeletal muscles in different muscle models was compared and analyzed. The muscle force and the change of the reduction force under different reduction paths were compared and simulated. The results showed that the greater the pinnate angle was, the greater the influence of muscle strength was. The biceps femoris short head played a major role in the femoral fracture reduction; the force in the z direction contributed the majority to the resulting force with maximums of 472.18 N and 497.28 N for z and resultant, respectively, and the rationality of the new musculoskeletal model was verified.
The surgical installation accuracy of the components in unicompartmental knee arthroplasty (UKA) is an important factor affecting the joint function and the implant life. Taking the ratio of the medial-lateral position of the femoral component relative to the tibial insert (a/A) as a parameter, and considering nine installation conditions of the femoral component, this study established the musculoskeletal multibody dynamics models of UKA to simulate the patients’ walking gait, and investigated the influences of the medial-lateral installation positions of the femoral component in UKA on the contact force, joint motion and ligament force of the knee joint. The results showed that, with the increase of a/A ratio, the medial contact force of the UKA implant was decreased and the lateral contact force of the cartilage was increased; the varus rotation, external rotation and posterior translation of the knee joint were increased; and the anterior cruciate ligament force, posterior cruciate ligament force and medial collateral ligament force were decreased. The medial-lateral installation positions of the femoral component in UKA had little effect on knee flexion-extension movement and lateral collateral ligament force. When the a/A ratio was less than or equalled to 0.375, the femoral component collided with the tibia. In order to prevent the overload on the medial implant and lateral cartilage, the excessive ligament force, and the collision between the femoral component and the tibia, it is suggested that the a/A ratio should be controlled within the range of 0.427?0.688 when the femoral component is installed in UKA. This study provides a reference for the accurate installation of the femoral component in UKA.
ObjectiveTo explore the feasibility and safety of clinical application of bipolar coagulation forceps in open thyroid operations and summarize the operation skill. MethodsThe clinical data of 347 cases performed thyroid operations with bipolar coagulation forceps and Harmonic scalpel respectively from October 2010 to October 2014 in our hospital were analyzed retrospectively. ResultsNo statistical differences was found on the operative time, intraoperative bleeding, postoperative drainage, and postoperative hospitalization of the two groups (P > 0.05). The complications of transient palsy of recurrent laryngeal nerve and transient functional insufficiency of parathyroid were more in Harmonic scalpel group than in bipolar coagulation forceps group with statistical difference (P < 0.05). But there was no difference of the complications of airway obstruction, permanent injuries of recurrent laryngeal nerve, parathyroid and superior laryngeal nerve in the two groups (P > 0.05). ConclusionsThyroid operations with bipolar coagulation forceps are safe and feasible. Coagulation tightly along the thyroid capsule followed by incision with explicit subtle dissection is the key point of the decrease of complications.
Based on force sensing resistor(FSR) sensor, we designed insoles for pressure measurement, which were stable and reliable with a simple structure, and easy to wear and to do outdoor experiments with. So the insoles could be used for gait detection system. The hardware includes plantar pressure sensor array, signal conditioning unit and main circuit unit. The software has the function of data acquisition, signal processing, feature extraction and classification function. We collected 27 groups of gait data of a healthy person based on this system to analyze the data and study pressure distribution under various gait features, i.e. walking on the flat ground, uphill, downhill, up the stairs, and down the stairs. These five gait patterns for pattern recognition and classification by K-nearest neighbors (KNN) recognition algorithm reached up to 90% accuracy. This preliminarily verified the usefulness of the system.
This study explored the variation of bursting force of multi-chamber infusion bag with different geometry size, providing guidance for its optimal design. Models of single-chamber infusion bag with different size were established. The finite element based on fluid cavity method was adopted to calculate the fluid-solid coupling deformation process of infusion bag to obtain corresponding critical bursting force. As a result, we proposed an empirical formula predicting the critical bursting force of one chamber infusion bag with specified geometry size. Besides, a theoretical analysis, which determines the force condition of three chamber infusion bag when falling from high altitude, was conducted. The proportion of force loaded on different chamber was gained. The results indicated that critical bursting force is positively related to the length and width of the chamber, and negatively related to the height of the chamber. While the infusion bag falling, the impact force loaded on each chamber is proportional to the total liquid within it. To raise the critical bursting force of in fusion bag, a greater length and width corresponding to reduced height are recommended considering the volume of liquid needed to be filled in.
Objective To explore the application value of self-made tibial mechanical axis locator in tibial extra-articular deformity in total knee arthroplasty (TKA) for improving the lower extremity force line. Methods Between January and August 2012, 13 cases (21 knees) of osteoarthritis with tibial extra-articular deformity were treated, including 5 males (8 knees) and 8 females (13 knees) with an average age of 66.5 years (range, 58-78 years). The disease duration was 2-5 years (mean, 3.5 years). The knee society score (KSS) was 45.5 ± 15.5. Extra-articular deformities included 1 case of knee valgus (2 knees) and 12 cases of knee varus (19 knees). Preoperative full-length X-ray films of lower extremities showed 10-21° valgus or varus deformity of tibial extra joint. Self-made tibial mechanical axis locator was used to determine and mark coronal tibial mechanical axis under X-ray before TKA, and then osteotomy was performed with extramedullary positioning device according to the mechanical axis marker. Results All incisions healed by first intention, without related complications of infection and joint instability. All patients were followed up 5-12 months (mean, 8.3 months). The X-ray examination showed lt; 2° knee deviation angle in the others except 1 case of 2.9° knee deviation angle at 3 days after operation, and the accurate rate was 95.2%. No loosening or instability of prosthesis occurred during follow-up. KSS score was 85.5 ± 15.0 at last follow-up, showing significant difference when compared with preoperative score (t=12.82, P=0.00). Conclusion The seft-made tibial mechanical axis locator can improve the accurate rate of the lower extremity force line in TKA for tibia extra-articular deformity.
ObjectiveTo summarize the new ideas and new instruments in thyroid surgery. MethodsRelated literatures were reviewed and analyzed. ResultsTotal thyroidectomy had become the preferred option for differentiated thyroid cancer and multiple nodule goiter. The key change of surgery was from recurrent laryngeal nerve-protection to parathyroid-protection. Harmonic scalpel, bipolar coagulation forceps and Ligasure were used to thyroid surgery, which could shorten operation time and reduce operative bleeding. ConclusionThe ideas and techniques of thyroid surgery have changed, total thyroidectomy and parathyroid protection are being paid more and more attentions, and new instruments are used more extensively in thyroid surgery.
Pathological myopia, characterized by progressive elongation of the axial length and formation of posterior staphyloma, is accompanied by chorioretinal irreversible degeneration. It is also the focus and biggest challenge of myopia control and blindness prevention. For managing progressive early-onset pathologic myopia and myopic traction maculopathy, episcleral pressurization of macula is a practical option. It can be divided into posterior scleral reinforcement surgery and macular buckling surgery according to the presence or absence of operative top pressure ridge after surgery, both of which are different in terms of implanted materials, procedures and indications. The implanted materials, procedures and indications are different between the two. Under the background of soaring prevalence of myopia, it is necessary to modify and cautiously popularize the techniques of episcleral pressurization of macula to provide high level clinical evidence for management of pathological myopia.
Objective To compare the advantages and disadvantages of using the harmonic scalpel and bipolar coagulation forceps versus harmonic scalpel and conventional clamp-and-tie technique in open thyroid surgery.Methods One hundred patients indicated for thyroid surgery were randomly divided into two groups：the bipolar coagulation forceps group underwent surgery with harmonic scalpel and bipolar coagulation forceps，and the conventional clamp-and-tie group with harmonic scalpel and conventional clamp-and-tie technique，respectively.All operations were performed by the same group of doctors.The total operation time，intraoperative bleeding，mass diameter，postoperative drainage，and surgical complications （postoperative bleeding， postoperative recurrent laryngeal nerve paralysis，seroma，and permanent postoperative hypoparathyroidism） were compared.Results There were 48 valid cases in the bipolar coagulation forceps group， and 49 cases in the conventional clamp-and-tie group. There were no significant differences between two groups patients of age，gender，disease composition，and mass diameter（P＞0.05）.With the same operative approach， the total operation time，intraoperative bleeding，and the incidence of transient postoperative hypoparathyroidism in the bipolar coagulation forceps group were significantly lower than those in the conventional clamp-and-tie group （P＜0.001）.The postoperative drainage in the bipolar coagulation forceps group was more than that in the conventional clamp-and-tie group （P＜0.05）.There was no single case of postoperative bleeding，postoperative recurrent laryngeal nerve paralysis，seroma，and permanent postoperative hypoparathyroidism in both groups.Conclusions The combination of harmonic scapel with bipolar coagulation forceps provides significant advantages over the combination of harmonic scapel with conventional clamp-and-tie technique in open thyroid surgery.