BACKGROUND:Klinefelter nails and external fixation were commonly used treatment methods for Bennett fracture, but study about biomechanics of two methods was little. OBJECTIVE:To establish three-dimensional finite element models of Bennett fracture by Klinefelter nails and external fixation, and analyze its biomechanics. METHODS:Three-dimensional models of Bennett fracture were established by smal external fixation and Kirschner nail treatment. The Bennett fracture models established by smal external fixation treatment were considered as model A. Bennett fracture models established by Kirschner nail treatment were considered as model B. 120 N load was applied to the first metacarpal X-axis direction. The X-direction displacement and total displacement of model A and model B, and the fracture fragments stress of model A and model B were observed. RESULTS AND CONCLUSION:(1) In the X direction, the absolute values of maximum displacement and minimum displacement of model A at proximal fragment and distal fragment were less than model B;the maximum relative displacement, minimum relative displacement and average relative displacement of model A were less than model B. The differences of the average displacement of the proximal fracture fragment and the distal fragment, and the relative mean displacement in two models were statistical y significant (P<0.05). (2) In total displacement, absolute values of the maximum displacement and minimum displacement of model A at proximal fragment were less than model B;absolute values of the maximum displacement and minimum displacement of model A at distal fragment were less than model B;the maximum relative displacement, minimum relative displacement and average relative displacement of model A were less than model B. The differences of the average displacement of the proximal fracture fragment and the distal fragment, and the relative mean displacement in two models were statistical y significant (P<0.05). (3) The maximum stress value, a minimum stress value and the average stress values of fracture fragments of model A were significantly smal er than model B. The difference of the mean stress value in two models was statistical y significant (P<0.05). (4) These findings showed that the X-direction displacement and the total displacement were smal er, and the fracture fragments stress was uniform in smal external fixation and Kirschner nail treatment for Bennett fracture, indicating that smal external fixation for Bennett fracture has more advantages compared with Klinefelter nail.

Objective To analyze the reasons of the common complications happened after the operation of congenital syndactyly and to find the method of prophylaxis and treatment,and to improve the effects of treatment.Methods To classify the reasons of the complications happened after the operation of congenital syndactyly in 34 cases.Results The reasons of the complications included that the patients were not operated by special course of study doctors in 9; operation at an inappropriate opportunity in 8;the method of web taken shape was improper in 7;the method of nail taken shape was improper in 4; the fixation and training was unsuitable in 6. Conclusions The complications happened after the operation of congenital syndactyly will be reduced much , provided that grasping the right opportunity and selecting the proper method of web or finger tip taken shape before operation , taking care of the transformations of blood vessel and nerve in operation , fixing firmly and training appropriately after operation.

Objective To investigate the clinical effect of reconstruction of soft tissue defect in non-weight-bearing area of the foot with trimmed free anterolateral thigh muscle flap combined with skin grafting. Methods From January, 2009 to January, 2017, 25 patients with soft tissue defect in foot and ankle were treated with transplan-tation of the trimmed free anterolateral thigh muscle flap combined with skin grafting. Of the 25 cases, there were 5 cases located in medial foot, 10 cases in dorsum of foot, 7 cases in external of foot and 3 cases in the toe. The areas of wounds were 8.0 cm ×6.0 cm to 18.0 cm ×10.0 cm. The anterolateral thigh muscle flap was from 4.0 cm ×3.0 cm ×0.3 cm to 10.0 cm×8.0 cm×1.5 cm. All the cases were operated in fracture fixation and wound without obvious infection. Early rehabilitative exercise under the protection of orthosis were done after 4 weeks of the operation and to assess. The injuried limb function were assessed in 1 year postoperatively according to Marylands scale. Results All cases were followed-up for 12 to 24 months (average, 16.2 months). All the muscle flaps and skin survived. The healing time were 12 to 24 days, averaged of 17.1 days. Patients could wear shoes normally and resume normal life and work. The appearance and walking function were satisfying and no further debulking procedures were needed . The surgery function were assessed according to Marylands scale, and the results was 22 cases for excellent, and 3 cases for good. Conclusion Ttrimmed free anterolateral thigh muscle flap combined with skin grafting is a good option for the repair of foot and ankle defect at non-weight-bearing area, and it has the advantages such as the doner site is small inva-sive, the muscle flap is easy to be harvested, and can avoid debulking surgery to wear shoes normally.