Finite element analysis can be used to study the change of the structure and the interior field intensity of human and animal body organs and tissues with simulation experiment. We in our research used finite element analysis software to analyze and solve the spinal cord surface potential problems, and investigated the transmission features of signals generated by interneurons in spinal nerves which were related with body motion control and sensory processing. A three dimensional model of electrical source in rat spinal cord was built, and the influence on potential distribution on spinal cord surface caused by position changes of electrical source in transverse direction and dorsoventral direction were analyzed and calculated. We obtained the potential distribution curves of spinal cord surface and found that the potential distribution on spinal cord surface showed monotone. In addition, potentials of some registration points were smaller than that of registration points around.
ObjectiveTo systematically evaluate the effectiveness and safety of dezocine versus fentanyl for postoperative patient-controlled intravenous analgesia (PCIA). MethodsWe electronically searched the specialized trials registered in The Cochrane Library (Issue 2, 2013), the Cochrane anesthesia group, MEDLINE, EMbase, CBM, CNKI, VIP and WanFang Data from inception to February, 2013. Randomized controlled trials (RCTs) on dezocine versus Fentanyl for postoperative PCIA were included. RevMan 5.0 software was used for meta-analysis after critically literature screening, data extracting and assessing of methodological quality independently by two reviewers. ResultsA total of 15 RCTs involving 1 116 patients were finally included. The results of meta-analysis showed that there was no significant difference in postoperative analgesia and sedation at the hour-points of 2 h, 4 h, 6 h, 8 h, 12 h, 24 h, and 48 h after surgery. As for safety, the incidences of postoperative nausea, vomiting, skin pruritus, respiratory depression and uroschesis in the dezocine group were lower than those in the fentanyl group. ConclusionCompared with fentanyl, dezocine has the same effects of analgesia and sedation for PCIA; its incidence of adverse reactions is lower, so dezocine is safer in clinic.
ObjectiveTo explore necessity, safety, and clinical significance of pelvic floor reconstruction following laparoscopic abdominoperineal resection for low rectal cancer. MethodsThirty-seven patients with low rectal cancer admitted to our hospital from July 2013 to January 2016 were collected, who were divided into reconstruction group and non-reconstruction group according to the pelvic floor reconstruction or not. The complications were compared in two groups. ResultsThe laparoscopic abdominoperineal resections were successfully completed in all the patients with low rectal cancer, there was no case of conversion to open surgery. The operative time was (173.6±18.3) min, the suture time of pelvic floor peritoneal was (28.6±7.5) min. The postoperative following-up was 3-24 month. There were 5 cases (22.7%) of complications in the non-reconstruction group, included 2 cases of adhesive intestinal obstruction, 1 case of perineal incision hernia, 1 case of pelvic effusion and infection, 1 case of radiation enteritis caused by radiotherapy. There was 1 case (6.7%) of adhesive intestinal obstruction in the reconstruction group. Although the incidence of postoperative complications in the reconstruction group was lower than that in the non-reconstruction group, there was no significant difference between these two groups (χ2=2.367, P=0.096 1). ConclusionThe preliminary results of limited cases in this study show that it is not essential for pelvic floor reconstruction following laparoscopic abdominoperineal resection for rectal cancer, but it could obviously decrease difficulty of operation for postoperative reoperation, especially for postoperative radiotherapy patients, and prevent occurrence of radiation enteritis. It is still necessary because it is more consistent with principle of open surgery, Hem-o-lok 3-0 Angiotech Quilltm clip or barbed suture closure of pelvic peritoneum, it is technically safe and feasible.
ObjectiveTo explore the causes of bile duct injury due to laparoscopic cholecystectomy (LC) and the preventive methods. MethodsA total of 18 patients with bile duct injury (with the occurrence rate of 0.4%) after LC between January 2003 and December 2012 were included. The patients included 5 males and 13 females with the age of 29-63 years old[averaging (42.3±3.6) years old]. The clinical data of the patients were retrospectively analyzed. ResultsIn the 18 cases of bile duct injury, 5 cases occur in emergency operation, 13 cases in selective operation. The operators were attending physician in 13 cases, and senior position in the other 5 cases. The reasons of the injury included misjudgment of the cystic duct in 9, duct aberrance in 3, excessive stretch of cystic duct in 2, 2 Mirizzi syndrome withⅠ-type surgical injury in 2, and right liver duct injury because of inappropriate stripping of gallbladder in 1. ConclusionThe operator's experience, severe conglutination and the bile duct aberrance are the chief causes. Preventive methods include strict system of operation accession, careful selection of candidates, timely laparotomy, and paying attention to the accumulation of operation experience and skills.
ObjectiveTo investigate the effectiveness of different free flaps in the repair of large defects after resection of scalp malignant tumors. MethodBetween March 2012 and January 2015, 18 patients with large defect after resection of scalp malignant tumors were treated with different free flaps. There were 13 males and 5 females with an average age of 49 years (range, 18-72 years). There were 17 cases of squamous carcinoma and 1 case of dermato-fibril sarcoma protuberans. The defect size ranged from 15 cm×12 cm to 22 cm×17 cm after resection of tumors. Defects were repaired with anterolateral thigh flap in 5 cases, latissimus dorsi myocutaneous flap in 6 cases, thoracodorsal artery perforator flap in 3 cases, and latissimusdorsi muscle flap plus intermediate split thickness skin graft in 4 cases. The flap size was 17 cm×14 cm to 24 cm×19 cm. The donor sites of the skin flap were covered with skin graft, while the donor sites of the muscle flap were directly sutured. ResultsOf 14 skin flaps, the other 13 flaps survived except 1 flap necrosis; all muscle flaps survived. The patients were followed up 5-33 months (mean, 20 months). Three patients died because of intracranial metastasis at 5, 7, and 13 months after operation, respectively. Two patients had local recurrence and underwent secondary operation. The results of both appearance and function were satisfactory; secondary operation of thinning the flaps was performed in 4 cases of bulky flaps. The flaps had good wear resistance, without ulceration during follow-up. No obvious impairment was observed after harvesting latissimus dorsi myocutaneous flap. ConclusionsLarge scalp defects after malignant tumor resection can be effectively repaired by proper application of different free flaps.
ObjectiveTo explore the mechanical stability of the three-dimensional (3-D) external fixator for osteoporotic fracture so as to provide the biomechanical basis for clinical application. MethodsForty-five fresh frozen adult tibial specimens were selected to rapidly prepare the extracorporal tibia osteoporotic fracture models, and were randomly divided into 3 groups (n=15). Fractures were fixed with 3-D external fixators (3-D external fixators group), intramedullary nails (intramedullary nail group), and plate (plate group) respectively. Five specimens randomly from each group were used to do axial compression test, three-point bending test, and torsion test with microcomputer control electronic universal testing machine, then the mechanical parameters were calculated. ResultsIn the axial compression test, the displacement of 3-D external fixator group and intramedullary nail group were shorter than plate group, showing significant differences (P<0.05); but no significant difference was found between 3-D external fixator group and intramedullary nail group (P>0.05). In the three-point bending test and torsion test, the deflection and the torsional angle of 3-D external fixator group and intramedullary nail group were smaller than plate group, showing significant differences (P<0.05); but no significant difference was found between 3-D external fixator group and intramedullary nail group (P>0.05). ConclusionThe 3-D external fixator can fix fracture three-dimensionally from multiple plane and it can offer strong fixing. It is biomechanically demonstrated to be suitable for osteoporotic fracture.
ObjectiveTo investigate the surgical methods and effectiveness to use the iliac flap combined with anterolateral thigh flap for repair of the first metatarsal bone and large skin defect. MethodsBetween January 2013 and January 2016, iliac flap combined with anterolateral thigh flap was used to repair the first metatarsal bone and large skin defect in 9 patients. There were 5 males and 4 females, with a median age of 15 years (range, 10 to 60 years). The causes included traffic accident injury in 6 cases and crush injury of machine in 3 cases. The average time from injury to operation was 3 hours to 14 days (mean, 7 days). The size of skin soft tissue defect ranged from 10 cm×6 cm to 20 cm×10 cm. The size of first metatarsal bone defect ranged from 2 cm×1 cm to 5 cm×1 cm. The size of iliac flap was 3.0 cm×1.5 cm to 6.0 cm×1.5 cm, and the size of anterolateral thigh flap was 10 cm×6 cm to 20 cm×10 cm. The donor site was directly sutured or repaired by free skin graft. ResultsAfter operation, the composite flaps survived with primary healing of wound; the skin grafts at donor site survived and the incision healed by first intention. All patients were followed up 6 months to 2 years (mean, 1.6 years). X-ray examination showed that the bone healing time was 3.5-5.0 months (mean, 4 months). The flap had soft texture, good color and appearance. All patients could normally walk. According to the American Orthopaedic Foot and Ankle Society (AOFAS) standard, the foot function was excellent in 6 cases and good in 3 cases, and the excellent and good rate was 100% at last follow-up. ConclusionThe iliac flap combined with anterolateral thigh flap for repair of the first metatarsal bone and large skin defect is a practical way with good shape at one stage.
ObjectiveTo compare the clinical efficacy of carotid endarterectomy (CEA) and carotid artery stenting (CAS) in the treatment of patients with carotid artery stenosis, and to provide a more abundant evidence-based medicine for the treatment of CEA and CAS in patients with carotid artery stenosis. MethodsForty patients with carotid artery stenosis were randomly divided into CEA group and CAS group based on the operative indication. Patients in CEA group were given carotid endarterectomy treatment and those in CAS group were given carotid artery stenting treatment. Then clinical efficacy of the two groups were observed and compared. ResultsIn terms of the occurring rate of perioperative complications, cardiovascular events in 3 months after operation, and some major end events such as stroke, death and so on, the comparative difference between the two groups was of no statistical significance (P > 0.05). Through the followed-up visits of 12 months, the comparative difference between the two groups was also of no statistical significance (P > 0.05) in terms of the occurring rate of carotid artery restenosis and disabling or fatal stroke. ConclusionsFor patients with severe extracranial carotid stenosis under indication of operation treatment, carotid endarterectomy and carotid artery stenting are of equivalent clinical efficacy, and both of them are of high security, although further study with large-amount and evidence-based medical data in long term from multiple centers is still in need.
ObjectiveTo explore the effectiveness of UC ultra-congruent rotating platform prosthesis in the treatment of knee osteoarthritis by comparing with fixed-bearing implant. MethodsThe clinical data were retrospectively analyzed, from 98 patients (98 knees) with knee osteoarthritis undergoing primary total knee arthroplasty between January 2011 and December 2012. The UC ultra-congruent rotating platform prosthesis was used in 56 cases (mobile-bearing group) and fixed-bearing implant was used in 42 cases (fixed-bearing group). There was no significant difference in gender, age, side, weight, disease duration, grading of arthritis, the number of varus and valgus malformation, preoperative range of motion of the knee, the Knee Society Score (KSS) score, the visual analogue scale (VAS) score, femorotibial angle, tibial angle, and articular surface angle between 2 groups (P>0.05). The operation time (including anesthetic time), intraoperative blood loss, hospitalization time, total hospitalization expenses, postoperative range of motion of the knee, the KSS score, and the VAS score were compared. The femorotibial angle, tibial angle, and articular surface angle were measured on the basis of anteroposterior and lateral X-ray films, and prosthesis loosening was observed. ResultsThere was no significant difference in the operation time, intraoperative blood loss, and hospitalization time between 2 groups (P>0.05), while the total hospitalization expenses of fixed-bearing group were significantly lower than those of the mobile-bearing group (t=8.506, P=0.000). The patients were followed up 16-30 months in the mobile-bearing group, and for 16-38 months in the fixed-bearing group. Postoperative complications occurred in 3 cases (7.14%) of the fixed-bearing group (1 case of fat liquefaction of incision, 1 case of joint stiff, and 1 case of anterior knee pain), and in 3 cases (5.36%) of the mobile-bearing group (1 case of delayed wound healing, and 2 cases of anterior knee pain); there was no significant difference in the complication rate between 2 groups (χ2=0.133, P=0.516). At last follow-up, the KSS score, VAS score, range of motion of the knee, femorotibial angle, tibial angle, and articular surface angle were superior significantly to those before operation in both groups (P<0.05), but no significant difference was found between 2 groups (P>0.05). No radiographic signs of radiolucent line, prosthetic dislocation, patellar dislocation, prosthetic loosening, and fracture was found. ConclusionUC ultra-congruent rotating platform prosthesis in the treatment of knee osteoarthritis can effectively improve the knee joint function and relief pain, which has the same short-term effectiveness to fixed-bearing implant.
ObjectiveTo investigate the effectiveness of rotating-platform prosthesis for valgus knee deformity in total knee arthroplasty (TKA). MethodsA retrospective analysis was made on the clinical date of 25 cases (28 knees) of valgus deformity undergoing primary TKA by using Gemini MK II rotating-platform prosthesis. There were 6 males (7 knees) and 19 females (21 knees), aged from 47 to 82 years, with an average age of 64.8 years. The unilateral knee was involved in 22 cases and the bilateral knees in 3 cases. The causes included osteoarthritis in 20 cases (22 knees), rheumatoid arthritis in 4 cases (5 knees), and traumatic arthritis in 1 case (1 knee). The disease duration was 2-22 years (mean, 10.4 years). The main clinical symptoms were arthralgia combined with limited movement. According to the Keblish grade, there were 13 knees of mild deformity, 11 knees of moderate deformity, and 4 knees of severe deformity. ResultsAll incisions healed by first intension. No complications of infection, cutaneous necrosis, deep venous thrombosis, and pulmonary embolism occurred. The postoperative follow-up duration was 12-60 months (mean, 25.4 months). Medial instability and palsies of nervus peroneus communis occurred in 1 and 2 cases respectively, and all were cured after symptomatic treatment. No patellar and polysthylene insert dislocation, prosthetic loosening or infection was observed. The Hospital for Special Surgery (HSS) score, femoral tibial angle, maximun flexion and extension angles, knee range of motion, and patellar score were significantly improved at last follow-up when compared with preoperative ones (P<0.01). ConclusionThe rotating-platform prosthesis for valgus deformity can obtain satisfactory effectiveness, but it requires precise soft tissue balancing technology, and the long-term effectiveness remains further observation.