Biomechanical study of anterior transpedicular screw fixation for subaxial cervical three-column injury / 中华创伤骨科杂志

Objective To compare the initial stability between anterior transpedicular screw (ATPS) fixation,anterior plate (AP) fixation and combining anterior and posterior (CAP) fixation for subaxial cervical three-column injury.Methods Six specimens of cervical spine were prepared.After measurement of the range of motion (ROM) of the intact cervical spine,the specimens were made into models of three-column injury.After the models were simulatively reconstructed using an anterior cervical cage,they were stabilized by ATPS,AP and CAP.After the ROMs of the models in the 3 fixation states were measured,the data were normalized by standardizing them to the intact state ROM which was set at 100％.The normalized ROMs of the models in the 3 fixation states were compared.Results The normalized ROMs of AP fixation state in flexion,extension,lefi lateral bending,right lateral bending,left axial rotation and right axial rotation were 119.68±8.34％,119.63±6.74％,115.20±7.91％,117.47±7.81％,120.67±5.99％ and 112.35 ± 8.42％,respectively,significantly larger than those of the intact state (P ＜ 0.05).The normalized ROMs of the other 2 states in all directions were significantly smaller than those of the intact state (P ＜0.05).The normalized ROM of ATPS state in flexion was 87.48 ± 5.31％,significantly larger than that of CAP state (69.60 ± 2.06％) (P ＜ 0.05).There were no significant differences between the normalized ROMs of ATPS state and those of CAP state in extension (65.53 ± 4.36％ versus 67.17 ± 3.10％),in left lateral bending (82.13 ± 2.85％ versus 82.30 ±4.69％),in right lateral bending (81.78 ± 3.42％ versus 81.27 ± 2.79％),in left axial rotation (83.20 ± 2.30％ versus 82.95 ± 2.40％),or in right axial rotation (83.03 ± 1.30％ versus 83.60 ± 6.56％) (P ＞ 0.05).Conclusions In subaxial cervical three-column injury,the initial stability of ATPS fixation may be superior to that of AP fixation and similar to that of CAP fixation.We believe that ATPS can provide enough initial stability for subaxial cervical three-column injury.

Advances on preventing femoral neck shortening after internal fixation of femoral neck fracture / 中华骨科杂志

Femoral head necrosis and nonunion is a common complication after surgery of femoral neck fracture.Recently,femoral neck shortening have caused attentions which can impact the function of hip.Incidence,mearsurement,influence factor,prevention and treatment of femoral neck shortening have been retrospective reviewed.Amount of femoral neck shortening with sliding compression system is significantly more than length of stability system,which is result from its own mechanism.However,effcacy of length of stability system still need a large scale of sample.It uses radiography to diagnose shortening.The present measurement methods include displacement of femoral head,xyz-axis measurement,the length of exposed screw,the collapse of femoral head.However,position,the angle of screen and the defect of the method would increase deviation.A measurement with simple,wide application and accuracy need to continue to explore.Apart from patients' condition,shortening also affected by the pattern and quality of surgery.Overall,older women,displacement fracture,unsatisfactory reduction will increase the risk and shrinkage of shortening.In addition,the pattern of the internal fixation becomes the research focus in the field of orthopedic clinical research.Including the transformation of sliding compression system device and design of novel device.How to combine them together organically could be a future development direction.Meanwhile,there are still in exploratory stage to decide whether biological combined with internal fixation can prevent shortening.Intertrochanteric osteotomy can achieve union and correct the limblength discrepancy,However,it did not restore the length of femoral neck.So,it is unknown that whether the method can solve the slight shortening which have impacted the hip function.

Mitochondrial function and its correlation with age in articular chondrocytes of Kashin-Beck disease / 西安交通大学学报(医学版)

Objective To evaluate the mitochondrial function of chondrocytes in Kashin-Beck disease (KBD) patients and its correlation with age.Methods Mitochondrial function was evaluated by analyzing the activities of respiratory chain enzyme complexes and citrate synthase (CS),intracellular adenosine triphosphate (ATP)contents, changes in mitochondrial membrane potential (ΔΨm),as well as the intracellular reactive oxygen species (ROS) contents.Correlation of mitodhondrial function and age was analyzed with linear regression.Results Activities of complexes Ⅱ (P = 0.001 ),Ⅲ (P = 0.005 )and Ⅳ (P = 0.005 )were reduced in KBD articular chondrocytes compared with cells from normal controls.However,the mitochondrial mass was increased in KBD samples. Cultured KBD chondrocytes had reduced cellular ATP level (P = 0.001 )and mitochondrial membrane potential (P =0.001),but increased citrate synthase activity (P =0.04)and intracellular ROS level (P <0.001).We found no correlation between mitochondrial function and donor age either in normal or in KBD chondrocytes. Conclusion Mitochondrial function is altered in articular chondrocytes of KBD,and no correlation was found between mitochondrial function and donor age.

Meta-analysis of therapeutic effects of computer-assisted navigation versus conventional total knee arthroplasty / 中国组织工程研究

BACKGROUND:It is stil controversial whether computer-assisted navigation elevated the accuracy and clinical outcomes of total knee arthroplasty. OBJECTIVE:To analyze the literatures in English and Chinese on computer-assisted navigation total knee arthroplasty, and to evaluate the clinical outcomes between computer-assisted navigation and conventional total knee arthroplasty. METHODWe retrieved PubMed, Ovid, Elsevier, China National Knowledge Infrastructure and Digital Library for literatures concerning randomized control ed trial of clinical outcomes of computer-assisted navigation and total knee arthroplasty published from January 1st 2005 to December 31st 2013. Meta analysis was performed with RevMan 5.0 software from the Cochrane col aboration. Clinical outcomes of computer-assisted navigation total knee arthroplasty and conventional technique were compared. The heterogeneity of data was checked. RESULTS AND CONCLUSION:A total of 16 randomized control ed papers were included in this analysis. Computer-assisted navigation group consisted of 1 322 knees, and the conventional group consisted of 1 299 knees. Compared with the conventional group, patients in the computer-assisted navigation group had a significantly lower risk of implant malalignment at more than 3° as wel as more than 2°, malalignment for both coronal femoral component and coronal tibial component of>3°, and both sagittal femoral component alignment and tibial slope at>3° malalignment. The meta-analysis did not find a significant difference in the sagittal tibial component alignment, the rates of complications, axial (rotational) alignment of the femoral component and the tibial component between both groups. These data indicated that computer-assisted navigation group had significant improvement in alignment of the limb and the component position, but long-term clinical outcomes using computer-assisted surgery in total knee arthroplasty require further investigation.

Efficacy and safety of tranexamic acid application in total hip arthroplasty:a meta-analysis / 中国组织工程研究

BACKGROUND:Whether tranexamic acid can effectively and safely reduce blood loss and al ogeneic transfusion rate in total hip arthroplasty remains controversial at present. OBJECTIVE:To assess the efficacy and safety of tranexamic acid administration in total hip arthroplasty using meta-analysis. METHODS:Clinical randomized control ed trials concerning tranexamic acid application in total hip arthroplasty published from January 1969 to December 2013 were retrieved from the PubMed, Ovid, Elsevier, Cochrane library, China National Knowledge Infrastructure and Wanfang database. Intraoperative blood loss, postoperative blood loss, total blood loss, al ogeneic transfusion rate and incidence of venous thromboembolism were compared using meta-analysis between the tranexamic acid and control groups. Detection and literature references were used as supplementary data. RevMan 5.0 software provided by Cochrane col aboration was used for meta-analyses. Conclusion was obtained according to analysis. The analysis checked the heterogeneity of data. RESULTS AND CONCLUSION:After comprehensive and rigorous screening, 19 high-quality (Jadad score not less than 3) randomized control ed studies were included. Meta-analysis results demonstrated that compared with the control group, tranexamic acid decreased the total blood loss [weighted mean difference (WMD)=-341.04, 95%confidence interval (CI) (-508.10,-173.97), P<0.001], intraoperative blood loss [WMD=-63.26, 95%CI (-111.33,-15.18), P=0.01] and postoperative blood loss [WMD=-229.53, 95%CI (-338.11,-120.94), P<0.000 1], and diminished al ogeneic transfusion rate [relative risk=0.45, 95%CI (0.35, 0.57), P<0.000 1] in patients undergoing total hip arthroplasty. No significant difference in incidence of venous thromboembolism was detectable. These data suggested that tranexamic acid could reduce blood loss and transfusion rate in patients undergoing total hip arthroplasty without increasing the risk of incidence of venous thromboembolism.

Biomechanical study of the sustentaculum tali screw placement for the treatment of Sanders type Ⅱ calcaneal fracture / 中华骨科杂志

Objective To explore the necessity and function of the sustentaculum tali screw placement for the treatment of Sanders type Ⅱ calcaneal fracture.Methods The data of Dicom that CT scan with bone was input into Mimics 12.0 software and Ansys 13.0 software for construction of calcaneus three-dimensional finite element model.Then,this model was imported into Solidworks 2010 software.Type Ⅱ calcaneal fracture model was established according to Sanders type cutting of calcaneus.Geometric parameters of AO calcaneal plate and screws were imported to the Solidworks 2010 software.Two internal fixation simulations were established based on the calcaneal model.In one model,the steel was placed on the outside with bone and the cancellous' bone screws were infiltrated respectively into the vertical bone since two screw holes which under the articular surface behind the steel plate,two screw holes which rear of the steel plate,a screw hole of the below calcaneus,two screw holes which in front of steel plate.In another model,a cortical bone screw was infiltrated into the sustentaculum tali through the bottom screw hole of articular surface of the steel plate.The two internal fixation models were loaded under the same condition,and non linear finite element analysis was carried out.The stress distribution in the two internal fixation models was calculated respectively.Results The maximum principal stress focused on the cortical bone of sustentaculum tali in both of the models under the same condition of loading.Bone joint displacement,maximum principal stress of calcaneal and internal fixation system in the model with sustentaculum screw fixation were smaller than that in the model without sustentaculum screw fixation.The stress in the model with sustentaculum screw fixation was more dispersed.Conclusion The placement of sustentaculum tali screw is essential for fixation of type Ⅱ calcaneal fracture to achieve the biomechanical stability and can be used in clinical.

Surgical management for avulsion fracture of calcaneal tuberosity / 中华骨科杂志

Objective To discuss the operative methods and cnrative effect of calcaneal tuberosity fracture.Methods The data of 15 patients with calcaneal tuberosity fracture was retrospectively analyzed who received treatment between January 2008 and June 2011.There were 9 males and 6 female,with the age ranging from 31 to 68 years (average,51.4 years).All the patients had unilateral acute injury,with the left foot in 7 cases and the right foot in 8 cases.According to the Beavis classification,there were 3 cases in type Ⅰ and 12 cases in type Ⅱ.All the cases in type Ⅰ and 10 cases in type Ⅱ were treated with open reduction and screw fixation.The other 2 cases in type Ⅱ with larger fragment involving a portion of the subtalar joint were treated with plate and screw fixation.The effect of the treatment was assessed according to the ankle and hindfoot score system of American Orthopaedic Foot and Ankle Society (AOFAS) after the operation.Results Ten patients were followed up for 12 to 36 months (average,20 months).The healing time in these patients ranged from 8 to 25 weeks (average,12 weeks).The postoperative score ranged from 47 to 100 points (average,91.1 points).There were 7 cases which received excellent effect,2 cases,good,and 1 case,poor.The rate of excellent and good was 90％.Necrosis of skin and soft tissue and exposure of the plate happened to one patient,who eventually healed after 3 weeks by debridement with plate preserved and peroneal artery perforator flap transplantation.Loss of reduction happened to another patient,who was treated with the revision surgery by open reduction and screw fixation again.Conclusion To patients with obvious Fracture displacement whose soft tissues are irritated severely.Emergency open reduction and internal fixation operation should be offered to prevent the necrosis of the flaps as far as possible.To patients with small fractures,it is advisable to choose open reduction and large diameter screw fixation,while plate and screw fixation may be better for patients with larger tuberosity fragment,especially when the fracture line extends to the facet of the subtalar joint.

Interphalangeal joint replacement arthroplasty for the treatment of traumatic arthritis / 中华老年医学杂志

Objective To investigate the clinical effects and operation key-points of interphalangeal joint replacement arthroplasty for the treatment of traumatic arthritis.Methods From March 2005 to December 2010,5 patients with post-traumatic arthritis undergoing interphalangeal joint replacement arthroplasty in our hospital were selected.The operation indications,treatment of intraoperative flexor and extensor tendon lesion and postoperative rehabilitation were evaluated.Results Operative incisions of 5 cases were primary healing in class I grade A.Stitches were taken out 2 weeks after the operation.Patients were followed up for 1.5 years.The range of interphalangeal joint motion was 0 to 90 (extension/flexion) with no pain at end of follow-up.The hand function was excellent in 3 cases and good in 2 cases according to total active motion (TAM)hand function evaluation.Conclusions Interphalangeal joint replacement arthroplasty is an effective treatment for traumatic arthritis.Preoperative indications evaluation and postoperative rehabilitation should be focused on the treatment.

Modified Stoppa approach for treatment of anterior pelvic ring fractures / 中华创伤杂志

Objective To investigate the feasibility and effects of modified Stoppa approach in treatment of anterior pelvic ring fractures.Methods The therapeutic effects of 21 patients with anterior pelvic ring fractures treated through the modified Stoppa approach from June 2008 to August 2011 were summarized and analyzed.According to Tile classification,there were seven patients with type A2 fractures,six with type B2 fractures,five type B3 fractures and three type C2 fractures.Surgical treatment through the modified Stoppa approach included anterior pelvic ring plates for 14 patients,anterior pelvic ring plates and external fixators for four and anterior pelvic ring plates and sacroiliac joint compressed cannulated screws for three.The fracture reduction and post-operative function were assessed by Matta criteria and Majeed system respectively.Results The incision length of the modified Stoppa approach ranged from 10 to 12 cm ( average,11 cm).The operation time ranged from 70 to 120 minutes ( average,95 minutes).The intra-operative blood loss ranged from 400 to 1 000 ml (average,700 ml ).According to the Matta criteria,all 21 patients obtained sound reduction,of whom 15 patients had bony union after 8-20 months follow-up post-operatively.The Majeed score in all patients showed a gradual increase postoperatively.Conclusions The modified Stoppa approach is characterized by convenience and directness in making incisions,clear operation field,easy reduction,few complications and fast recovery and hence is an ideal choice in surgical treatment of anterior pelvic ring fractures.

Biomechanical study on three-dimensional internal fixation for unstable posterior pelvic ring fracture / 中华创伤杂志

Objective To compare the biomechanical difference of two internal fixation approaches for the posterior pelvic ring fracture dislocation.Methods Six fresh adult cadaver pelvic specimens were tested biomechanically.Then,the specimens were subjected to Denis-I sacral pelvic fracture.The specimen was first fixed with improved Galveston fixation and then with improved Galveston fixation plus sacral rod.Biomechanical tests were performed from vertical and reversed directions on the fixed pelvis.Results Under vertical compression,the biomeehanical value of the improved Galveston fixation plus sacral rod was lower than that of the improved Galveston fixation,with no statistical difference between two methods(P ＞ 0.05).Under the reversed compression,the biomeehanieal value of the improved Galveston fixation plus sacral rod was lower than that of the improved Galveston fixation,with statistical difference between two groups(P ＜ 0.05).Conclusion The improved Galveston fixation combined with sacral rod can increase the anti-reverse stability of the posterior pelvic ring.

Treatment of thoracolumbar vertebral fractures with monosegment pedicle instrumentation through posterior approach / 中国医师进修杂志

Objective To investigate the method and effect of monosegment pedicle instrumentafinn on thoraeolumbar vertebral fracture.Methods Sixteen patients with thoracolumbar vertebral fractures treated by open reduction and monosegment pedicle instrumentation through posterior approach.Posterolateral bone grafting was done in all cases,9 cases were quite decompressed using laminectomy.The follow-up time Was 8-24 months.The spine radiographs and CT scan were taken pre-and post-operation.The parameters used for clinical evaluation were the Denis pain scale,neurological evaluation by the Frankel scale and bone graft healing evaluation by the Suk scale.Results All of the fractures were reduced satisfactorily during the follow-up.The height of the injured vertebral improved rate was 30.8%,kyphosis of the injured vertebral segment rectified obviously.There was no implant break,and no signs of losing were observed in any patient.Nine patients which had neurological deficiency had average improvement more than one degree by the Frankel scale.After operation the pain score was P1 in 14 patients and P2 in 2 patients.Condnsion For the appropriate patients with thoracolumbar vertebral fractures,open reduction and internal fixation of monosegment pedicle instrumentation through posterior approach is a safe and effective method.

Treatment of open tibia shaft fractures using unreamed intramedullary nail / 中华创伤骨科杂志

Objective To introduce the method,characteristics and indication of unreamed in-tramedullery nailing in treatment of open tibia fractures.Methods 28 cases were classified according to the Gustilo method:18 belonged to type I,8 type II and 2 type III a.26 nails with 8mm in diameter and 2 nails with 7mm in diameter were used.Results All cases were fixed successfully with unreamed nailing without any X-ray aids.All of fractures had no infection,and healed in an average time of 5.6 months.There were no broken nails and screws in this series.Conclusion The unreamed intramedullary nailing is an advantageous therapeutic method with simple management,little trauma and wide indication in management of open tibia fractures.

Replacement of humeral head prosthesis for older fractures of proximal humerus / 中华骨科杂志

Objective To evaluate the results and relating factors in the treatment of proximal humeral fractures by replacement of humeral head prosthesis. Methods From March 2000 to March 2003, 21 cases with proximal humeral fractures, which were 10 males and 11 females aging from 62 to 82 years with an average of 72.3 years, were admitted to our hospital. All the patients were underwent one-stage operation of humeral head hemiarthroplasty through the anteromedial approach of shoulder joint. The average operative time was 60 minutes (range, 40 to 80 minutes) with a blood loss ranging form 200 ml to 300 ml. According to Neer classification, 6 cases were three-part fractures, 13 four-part fractures, and 2 head-splitting fractures. There were 18 fresh fractures and 3 old fractures. All the fractures were treated with replacement of humeral head prosthesis. After operation, the upper extremity was immobilized for 6 weeks, however, physical therapy, including pendulum, isometric elbow, and wrist and hand exercises, was begun on the first day after surgery. Results The follow-up ranged from 6 to 36 months with a mean period of 14.6 months. No lessening prosthesis, prosthesis dislocation, postoperative infection, nerve damage or periprosthesis fractures occurred. According to the scoring system modification for hemiarthroplasty (SSMH) of UCLA (Los. Angeles, California, USA) based on shoulder pain, functional status, muscle strength and range of motion, the average score was 24.5. Furthermore, the score was above 27 (excellent) in 3 cases, and 24 to 27 (good) in 14, and the excellent rate was 86%. The average score of pain was 9.3, function 8.6, muscle strength 8.2 in 21 cases. Conclusion Replacement of humeral head prosthesis is a preferable method for the treatment of proximal humeral fractures in the elderly patients, with significant effects in keeping the function and relieving the pain of the shoulder joint postoperatively.