Review of closed reduction techniques for femoral neck fracture / 中国骨伤

For patients with femoral neck fractures who plan to undergo internal fixation, satisfied alignment of fracture ends is an important prerequisite for internal fixation stability and fracture healing. There are many reports on the reduction methods of displaced femoral neck fractures, which can be summarized into three categories:First, the solely longitudinal traction of lower limbs, supplemented by other manipulations such as rotation and compression; Second, the resultant force formed by the longitudinal traction of lower limbs and the lateral traction;the third is accomplished by vertical traction in the axis of femur with hip joint flexed. Each reduction method has its own advantages, but no single method can be applied to all fracture displacement. In this paper, some classical reduction techniques in the literatures are briefly reviewed. It is hoped that clinicians will not be limited to a certain reduction method, they should analyze the injury mechanism and fracture displacement process according to the morphology features and flexibly select targeted reduction methods to improve the success rate of closed reduction of femoral neck fracture.

Disastrous triad of femoral head:femoral neck fracture meeting fracture-dislocation of femoral head / 中国骨伤

Femoral head and ipsilateral femoral neck fractures are serious and complicated injuries, which usually yield unsatisfactory results using conventional hip-preserving surgery. The key point of the management and prognosis mainly lies in femoral neck fractures. An apparent and consecutive relationship exists between femoral neck fractures and femoral head fracture-hip dislocation in such injuries. It is believed that disastrous triad of femoral head (DTFH) could summarize these specific injuries, and reflect the injury mechanism and prognostic characteristics. Based on our clinical observation and literature review, DTFH could be divided into three subgroups:TypeⅠ, common DTFH, in which femoral neck fractures occur following femoral head fractures-hip dislocation due to the same trauma; TypeⅡ, iatrogenic DTFH, in which femoral neck fractures come out in the caring process of femoral head fractures-hip dislocation; Type Ⅲ, stressed DTFH, in which femoral neck fractures occur after the management of femoral head fractures-hip dislocation. In the scenario, the line of femoral neck fractures locates distally to the femoral head fractures. Herein, we will discuss clinical characteristics of these types of DTFH.

Bone Grafting Can Promote the Prognosis of Displaced Femoral Neck Fractures: A Follow-up of the Clinical Significance of Bone Defects

Background@#Femoral neck fractures (FNFs) comprise a large proportion of osteoporotic fractures in Asia. However, the full range of prognostic variables that affect prognosis remains unclear. Here, we aimed to determine whether the severity of bone defects at the fracture site and other variables impact the prognosis of displaced FNFs. @*Methods@#We evaluated the incidence of FNF internal fixation failures at regular intervals after surgery in data collected retrospectively. Digital Imaging and Communications in Medicine (DICOM) magnetic resonance imaging data of the displaced FNFs of 204 patients (> 20 years old; mean age, 52.3 years; men, 55.4%) who underwent internal fixation were used to construct threedimensional (3D) virtual models of the femoral neck region. We calculated the position and volume of bone defect (VBD) using our independently developed algorithm and Mimics software. Each participant was followed up for at least 24 months; complications were noted and correlated with VBD and demographic and clinical variables. @*Results@#On the basis of VBD values calculated from virtual reduction models, 57 patients were categorized as having a mild defect, 100 as having a moderate defect, and 47 as having a severe defect. Age (p = 0.046) and VBD (p < 0.001) were significantly correlated with internal fixation failure. Multivariate analysis revealed that severe bone defects were associated with internal fixation failure (adjusted odds ratio [aOR], 23.073; 95% confidence interval [CI], 2.791–190.732) and complications (aOR, 8.945; 95% CI, 1.829–43.749). In patients with a severe defect, bone grafting was inversely associated with internal fixation failure (aOR, 0.022; 95% CI, 0.002–0.268) and complications (aOR, 0.023; 95% CI, 0.002–0.299). @*Conclusions@#Bone defect severity was associated with internal fixation failure and other complications. For young adults with large VBDs, bone grafting of the defect can reduce the risk of internal fixation failure. These results provide useful new quantitative information for precisely classifying displaced FNFs and guiding subsequent optimal treatments.

Vibration Characteristics of Hollow Screws and Locking Plates for Treating Femoral Neck Fractures / 医用生物力学

Objective To investigate the influence from natural and constrained modal of the hip joint on internal fixation after implantation of hollow screws and locking plates for treating femoral neck fractures. Methods CT image data of a patient with femoral neck fracture were analyzed, boundary of the hip joint was extracted to generate a three-dimensional (3D) model of the hip joint, and the assembly of common internal fixation models and hip joint models was established. Finite element simulation was then conducted, with focus on vibration characteristics. Results Vibration had a certain effect on internal fixation stability of hollow screws and locking plates. The occurrence of torsion would destroy the fixation environment of hollow screws and locking plates, resulting in a small displacement at the fracture end. In a constrained state, the modal frequency range was lower. Deformation of the vibration shape mostly occurred at proximal end of the femoral head, leading to the loosening phenomenon of internal fixation and prosthesis. A method for judging the stability of internal fixation was proposed from the perspective of vibration characteristics, and it was found that the stability of internal fixation with hollow screws was better than that of proximal locking plates. Conclusions For choosing internal fixation, influences from natural frequency of the screw and plate should be considered, so as to avoid natural frequency of the femur, which may cause resonance. The results can be used as a guidance for the selection of internal fixation materials and the design of structure and configuration.

Cyclic Stretch Promotes Migration of MC3T3-E1 Cells via Increasing Runx2 Expression / 医用生物力学

Objective To investigate the effects of cyclic stretch on migration of MC3T3-E1 cells and its related mechanism. Methods The strain loading system was used to stretch MC3T3-E1 cells cultured in vitro with 15% amplitude, to simulate the mechanical condition in vivo. The wound healing assay was used to detect the migration of MC3T3-E1 cells. Western blotting was used to test Runx2 expression. RNA interfering was used to decrease Runx2 expression. Results Cyclic mechanical stretch with 15% amplitude, 1.25 Hz frequency and lasting for 24 hours could promote the migration of MC3T3-E1 cells and increase the expression level of Runx2. Runx2 interference inhibited the migration of MC3T3-E1 cells in static culture condition. Interference with Runx2 expression in MC3T3-E1 cells could partially reduce the positive effect of cyclic mechanical stretch on cell migration. Conclusions Cyclic stretch can promote the migration of MC3T3-E1 cells, and Runx2 may play an important role in this process. This study provides experimental basis for finding innovative clinical treatment method to promote fracture healing.

Expert Concensus on Triune Personalized Treatment of Pelvic Tumor Based on Three-Dimensional Printing / 医用生物力学

The adjacent anatomy of the pelvis is complicated, with digestive, urinary, reproductive and other organs as well as important blood vessels and nerves. Therefore, accurate resection of pelvic tumors and precise reconstruction of defects after resection are extremely difficult. The development of medical 3D printing technology provides new ideas for precise resection and personalized reconstruction of pelvic tumors. The “triune” application of 3D printing personalized lesion model, osteotomy guide plate and reconstruction prosthesis in pelvic tumor limb salvage reconstruction treatment has achieved good clinical results. However, the current lack of normative guidance standards such as preparation and application of 3D printing personalized lesion model, osteotomy guide plate and reconstruction prosthesis restricts its promotion and application. The formulation of this consensus provides normative guidance for 3D printing personalized pelvic tumor limb salvage reconstruction treatment.

Application and controversy concerning dynamization of interlocking intramedullary nails to facilitate healing of long bone fracture / 中华创伤骨科杂志

Controversy exists concerning clinical application of dynamization of interlocking intramedullary nails. Some scholars believe that dynamization of interlocking intramedullary nails is an effective therapy for delayed union and nonunion of long bones, the tibia and the femur in particular, because it may promote healing of long bones. However, some hold that the dynamization may detriment fracture healing because it deteriorates the instability of the fracture ends. It helps foster the rate of fracture healing and reduce complications to understand the impact of dynamization on fracture healing, proper timing of the dynamization, and rational application of the dynamization methods. This review expounds the research progress in dynamization mechanisms, optimal timing of the dynamization and controversy over the treatment strategies.

Factors affecting the outcome of surgical treatment for intertrochanteric fractures / 中华创伤杂志

Objective:To investigate the factors affecting the outcome of surgical treatment for femoral intertrochanteric fractures.Methods:A retrospective case series study was conducted for 424 patients with intertrochanteric fractures admitted to four hospitals in Shanghai from January 2014 to December 2016. There were 200 males and 224 females, aged 45-98 years [(77.8±10.5)years]. Normal union was observed in 326 patients (normal union group), and abnormal union was founded in 98 patients including nonunion in 2 patients (abnormal union group). Data were recorded including the age, gender, injury side, AO classification, Evans-Jesen classification, thickness of femoral lateral wall, medial support, tip-apex distance, and screw position within the femoral head. Fracture healing was assessed. Univariate analysis was conducted to examine differences of the above factors between two groups, and Logistic regression was used to screen the main factors affecting fracture union. At the latest follow-up, the hip joint function was estimated according to the Oxford score system.Results:All patients were followed up for 1-3 years [(2.2±0.3)years]. Univariate analysis showed significant differences between two groups regarding the AO classification, Evans-Jesen classification, medial support, tip-apex distance, and screw position within the femoral head ( P<0.05). Multivariate regression analysis revealed that the simple fracture ( OR=1.030), medial support ( OR=0.395), tip-apex distance ≤25 mm ( OR=0.266) and inferior screw position ( OR=0.986) were significantly related to fracture union. The hip function in normal union group was (42.6±4.5)points, better than (35.4±3.2)points in abnormal union group ( P<0.05). Conclusion:The stability of intertrochanteric fracture is the most important factor for fracture union. The medial support, tip-apex distance ≤25 mm and inferior screw position are helpful to promote fracture healing and recovery of hip joint function.

Finite element analysis on Sander III calcaneal fractures fixed by crossing screws or steel plate / 医用生物力学

Objective To make comparative study on the immediate stability of intra-articular calcaneal fractures fixed by crossing screws and by plate. Methods A set of foot CT images from a normal male were collected to construct 3D finite element models of Scander-III calcaneau fracture fixed by crossing screws and by steel plate, respectively. The regular pattern of stress and displacement distributions on these two fracture models under vertical load of 700 N was analyzed. Results For the screw-fixed model, the stress was concentrated at the connecting area between screws and fracture ends, and the maximum stresses were different for screws at different places. While for the plate-fixed model, the stress was concentrated at the connecting area between plate and screw. The highest stress was concentrated in anterior segment of the plate. The maximum stresses of plate, screw and calcaneus were all lower than their shear strength. The displacements of intact calcaneus and fractures were concentrated on the posterior subtalar joints, and a larger displacement appeared on the internal part of joint facet. Conclusions Both crossing screws and steel plate can be used to fix calcaneal fractures with a preferable initial stability. Functional exercise and rehabilitation are recommended at early time after operation.

Cannulated screws plus separate vertical wirings for fixation of acute patella inferior pole fracture / 中华创伤杂志

Objective To investigate the feasibility and clinical effect of cannulated screws plus separate vertical wirings technique for acute fracture of the inferior pole of the patella.Methods From May 2012 to September 2013,14 patients with fresh closed unilateral fracture of the inferior pole of the patella were treated with the cannulated screws plus separate vertical wirings.Eight patients were injured in traffic collisions and 6 in fall accidents.Fracture AO classification was type 34A1 in 8 patients and type 34A2 in 6 patients.Time from injury to operation was 1-7 days (mean,2.5 days).Number of tie wires was determined according to the degree of fracture comminution.Fracture healing,fixed position and patellar length were evaluated by radiographic examination postoperatively.Knee mobility and Bostman evaluation system were investigated to analyze the clinical effect.Results All the patients obtained average 15-month follow-up (range,12 to 29 months).At postoperative 2 months,the fracture healed with good alignment of the broken bone and proper place of the internal fixation device noted on the X-ray films.At postoperative 6 and 12 months,X-ray films revealed fracture bony healing,good location of the wire internal fixation,and no apparent shortening of the patella.At the 12 months,range of knee motion was (126.0 ± 4.5) ° for flexion and (2.0 ± 1.7) ° for extension.Bostman functional score for patella fracture was (28.1 ± 1.9) points.And 12 patients were rated as excellent and 2 good,with excellence rate of 100％.Conclusion Cannulated screw fixation plus separate vertical wiring is effective to stabilize patella inferior pole fracture and has good results,indicating a recommended surgical method.

Effect of fixing distal radius fracture with volar locking palmar plates while preserving pronator quadratus / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>L-shaped incision of pronator quadratus (PQ) muscle along its radial and distal borders was always taken for distal radius fractures reduction and internal fixation. Repair of the PQ muscle was always recommended at the end of operation for some instructive reasons. But repair of PQ is not satisfied because of poor quality of muscle and fascial tissues which may cause pain or impede forearm pronation and supination for post-operative scarring around PQ. Inserting the locking palmar plate to pass under the pronator quadratus muscle and the locking screws are inserted through mini-incisions in pronator quadratus in some patients with distal radius fractures is a reasonable technique which can preserve the pronator quadratus. The purpose of this study was to evaluate and compare the clinical effects after volar plating of the distal radius fractures while preserving the pronator quadratus and pronator quadratus repair.</p><p><b>METHODS</b>Between September 2010 and April 2012, 65 patients (42 males and 23 females; aged 20-68 years and a mean age of 42.5 years) with distal radius fracture underwent open reduction and internal fixation using the volar locking palmar plates (Depuy or Smith companies). The patients were classified as 23A-2 through 23C-3 according to the Orthopaedic Trauma Association (OTA) classifications. All surgeries were completed by the same trained team. The volar locking palmar plates of distal radius performed with preserving pronator quadratus group involved 30 patients including 19 males and 11 females and performed with pronator quadratus repair group involved 35 patients including 23 males and 12 females. We compared the two groups for wrist pain, forearm range of motion, grip strength, perioperative complications and wrist functional recovery score.</p><p><b>RESULTS</b>The minimum follow-up for the whole cohort was one year. The differences between the two groups were significant with regard to wrist pain, forearm range of motion, grip strength and wrist function at 1, 2, and 6 weeks postoperatively, but insignificant at 6 and 12 months postoperatively. No significant differences were found in the perioperative complications and radiographs postoperatively.</p><p><b>CONCLUSIONS</b>Preservation of the pronator quadratus muscle is a satisfactory method for the treatment of majority of the fractures of the distal radius with volar locking palmar plates, as this technique can yield better early wrist function and shorten the rehabilitation.</p>

Radiographic and functional results of the intertrochanteric fractures with or without lateral femoral wall fractures using proximal femoral nail antirotation (PFNA) / 中华骨科杂志

Objective To evaluate the clinical effect of the intertrochanteric fractures with or without lateral femoral wall fractures using proximal femoral nail antirotation (PFNA).Methods From May 2008 to June 2011,102 patients with intertrochanteric fractures were treated with PFNA.In accordance with the preoperative three dimensional CT reconstruction(3D CT) images,the group A included 41 cases with lateral femoral wall fractures,and the other 61 cases with an intact lateral wall were in group B.According to the AO/OTA classification,there were 5 cases in 31-A2,36 in 31-A3 in group A,and 61 in 31-A2 in group B.The operative time,operative blood loss,average length of stay,postoperative X-ray images,and 3D CT images were collected for each patient.Time of partial weight-bearing,full weight-bearing and fracture healing were also recorded.Clinical evaluation was made using the functional recovery scale (FRS) of hip fractures.Results The mean operation time was 56±8 min in group A vs 45±6 min in group B; the mean blood loss was 238±21 ml vs 175±11 ml; the average length of stay was 17±3 days vs 15±3 days.On the postoperative radiography,the blowout of lateral trochanteric wall only occurred in 8 (19.5％,8/41) cases in group A and 3 (4.9％,3/61) in group B.According to the postoperative 3D CT,the similar findings were seen in 36 (87.8％.36/41) cases in group A and 45 (73.8％,45/61) in group B.Eighty-two cases were followed up for 6 to 35 months (mean.19.5 months).The mean FRS score was 64.2±4.8 points in group A and 76.5±7.9 points in group B.Conclusion When treating unstable intertrochanteric fractures,iatrogenic fractures in lateral trochanteric wall could be easily caused with using PFNA.3D CT could effectively evaluate iatrogenic trauma in the intertrochanteric fractures.

Effect of improved posterolateral minimally invasive approach combined with modular femoral head prosthesis in treatment of femoral neck fractures in elderly patients / 中华创伤杂志

Objective To compare the clinical effects of improved posterolateral minimally invasive approach and traditional posterolateral approach combined with modular femoral head prosthesis in the treatment of femoral neck fractures in the elderly. Methods The study involved 70 patients with femoral neck fractures (26 males and 44 females; at age range of 67-95 years,mean 78.3 years) treated from October 2008 to June 2010.There were 62 patients with fresh femoral neck fractures and eight with old femoral neck fractures (2-4 months post-injury),all of whom were type Ⅲ or Ⅳ fractures according to the Garden' s classification.All surgeries were completed by the same operation group.The improved posterolateral minimally invasive approach group involved 32 patients including 12 males and 20 females and the traditional posterolateral approach group involved 38 patients including 14 males and 24 females.The two groups were compared in aspects of incision size,operative time,perioperative complications,prosthesis stability and hip functional recovery. Results All patients were followed up for an average of 16 weeks (range,12-18 weeks).The differences between the two groups were significant regarding the incision length,perioperative blood loss,and blood product transfusio amount (P ＜0.01 ),but insignificant in operative time ( P ＞ 0.05 ).All patients were able to take weight-bearing walk six weeks postoperatively.The two groups showed significant difference in the hip joint function by Chamley's criteria six weeks postoperatively ( P ＜ 0.05 ),but insignificant difference in the hip joint function by Harris' s criteria at the last follow-up ( P ＜ 0.05). Conclusion The modified posterolateral minimally invasive approach combined with modular femoral head prosthesis is a satisfactory method in treatment of femoral neck fractures in senile patients,for it can result in less intra-operative soft tissue damage and blood loss,as well as shorter rehabilitation time.

Three-dimensional morphological characteristics measurement of ankle joint based on computed tomography image post-processing / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>As precise positioning of ankle radiography is not possible, quantitative measurement of all syndesmotic parameters on repeated ankle X-ray films may be of little value. The purpose of this study was to provide a set of scientific and objective evaluation criteria for assessing the quality of ankle fracture reduction accurately and reliably by an intelligent combining three-dimensional (3-D) computed tomography (CT) measurement model.</p><p><b>METHODS</b>From June 2008 to March 2011, all the thin-slice CT images of 100 cases (50 males and 50 females) with normal ankle joint scanned by 16-slice spiral CT were collected. Two-dimensional (2-D) and 3-D images of ankle joints were generated by using multiple planar reconstruction (MPR) and surface shaded display (SSD) respectively. The relevant parameters about bone structures and their relationship were measured and analyzed based on 3-D topological narrow division technique and 3-D measurement techniques combining essential elements of point, line and surface.</p><p><b>RESULTS</b>In this study, the mean distance from lateral malleolus tip to talocrural articular surface, the tip of medial malleolus anterior colliculus to talocrural articular surface and lateral malleolus tip to the tip of medial malleolus anterior colliculus were (22.83 ± 1.12) mm, (12.84 ± 1.09) mm, and (61.18 ± 2.03) mm respectively in male group, and (20.16 ± 1.00) mm, (10.30 ± 1.05) mm and (53.00 ± 1.40) mm respectively in female group. The above three parameters were correlated with gender, height and weight (P < 0.05). However, the mean perpendicular distance from lateral malleolus tip to the plane through the tip of medial malleolus anterior colliculus, the talocrural angle, later clear space, medial clear space, and the superior clear space were (9.93 ± 0.29) mm, (10.01 ± 0.38)°, (1.94 ± 0.16) mm, (2.78 ± 0.19) mm, and (3.14 ± 0.15) mm respectively in 100 cases, were not significance correlated with gender, height and weight (P > 0.05).</p><p><b>CONCLUSIONS</b>This study could provide a certain amount of relevant data for the standard of injured ankle anatomical reduction and the second surgery planning after malunion. The methods of measurement are reliable, reproducible, and easy to apply in practice.</p>

Digital measurement of bone tumor volume by CT three-dimensional reconstruction technology / 中华骨科杂志

Objective To discuss the measurement of bone tumor volume on the basis of three dimensional images segmentation technology. Methods Twenty patients with lacunar bone tumor from Tianjin hospital and Tongji hospital were included in the study from January 2010 to August 2010. There were 11 males and 9 females. Each patient was exposed to spiral CT preoperatively. Then these primitive CT dates were imported into digital orthopedics clinical research platform (SuperImage orthopedics edition 1.1, Cybermed Ltd). The volume and maximum diameter of bone tumor were measured before operation by three-dimensional reconstruction technology. The actual tumor volume was measured during the operation. The tumor volume was also calculated from plain X-rays and CT scans as ellipsoidal or cylindrical depending on the tumor configuration and presence or absence of a soft tissue component. Results The tumor volume was measured to be (14.92±7.34) mm3, (16.65±6.95) mm3 and (34.29±15.70) mm3 using three-dimensional reconstruction technology, intraoperative elevation, and traditional radiograph measurement separately. It was found that there was no difference regarding the outcomes of measurement between three-dimensional reconstruction technology and gross intraoperative measurement. But obvious difference was detected between gross intraoperative measurement and traditional radiograph measurement. Coefficient of correlation between diameter and volume of bone tumor was 0.325 (P=0.162). Conclusion Digital measurement is a precise, efficient,convenient and repeatable method for bone tumor measurement.

Application of new proximal femoral nail antirotation in treatment of subtrochanteric fractures / 中华创伤杂志

ObjectiveTo evaluate the clinical outcome of new proximal femoral nail antirotation (PFNA) in treatment of subtrochanteric fractures. MethodsThere were 31 patients with traumatic subtrochanteric fractures intramedullarily fixed with PFNA. The patients included 14 males and 17 fe-males at a mean age of 54.6 years (range 34-90 years). According to Seinsheimer classification of sub-trochanteric fractures, 14 patients were with type Ⅱ fractures (including four patients with type ⅡA,seven with type ⅡB and three with type ⅡC), 12 with type Ⅲ fractures (including eight with type ⅢA and four with type ⅢB), two with type Ⅳ fractures and three with type Ⅴ fractures. Close reduction was performed under traction and C-arm fluoroscopy in 26 patients and open reduction through a mini-incision before inserting the nail in five patients due to difficult close reduction. ResultsThe operation lasted for a mean time of 72.5 minutes (range 45-120 minutes), with mean blood loss of 127.5 ml (range 100-350 ml). Of all, 27 patients (87.1%, 27/31) were followed up for a mean duration of 14.3 months (range 8-24 months), which showed fracture union in all patients, with a mean union period of 17.4 weeks (range 10-21 weeks). According to Harris Hip Rate Scale, the results were. excellent in 21 pa-tients, good in two and fair in four, with excellence rate of 85.2% (23/27). ConclusionsPFNA is an effective device for treatment of subtrochanteric fracture, with a high union rate and a low complication rate, for it has advantages of easy use and minor trauma, low bleeding and stable fixation in operation.

Study of the morphology of heel spur and clinical significance: base on three-dimensional computed tomography / 中华外科杂志

<p><b>OBJECTIVES</b>To evaluate the characteristic morphology of heel spur, and to investigate the relationship of heel spur and plantar heel pain.</p><p><b>METHODS</b>From June 2005 to April 2009, 210 cases (254 feet) with heel spur (according to Denis Pain Scale) were divided into cases group 1 (P2, n = 46), 2 (P3, n = 44), 3 (P4, n = 42), 4 (P5, n = 36) and controls group (P1, n = 42). Three-dimensional reconstruction of heel spur was performed in all groups using volume rendering based on multi-slice CT data by Super Image orthopedics edition 1.0. The characteristic morphology of heel spur was observed and the data were measured and analyzed, involving the width of basilar part, the length, the angle between heel spur and planta pedis, and the angle between the longitudinal axis of calcaneus and heel spur.</p><p><b>RESULTS</b>Parts of cases groups displayed coarse arcuate edge and undersurface with one or more little heel spurs adhere to heel spur, of which the numbers were greater than controls group, especially in cases group 4. No significant difference of the width of basilar part of heel spur was found among 5 groups (F = 2.32, P > 0.05). However, obvious difference was found in the length, the angle between heel spur and planta pedis, and the angle between the longitudinal axis of calcaneus and heel spur (F = 8.23, 6.82, 5.87, P < 0.05). Compared with the controls group, the angle between heel spur and planta pedis of cases groups had higher degrees, but the difference of the other data presented irregular.</p><p><b>CONCLUSIONS</b>The characteristic morphology of heel spur varies in patients associated with plantar heel pain. No correlation is found between the severity and the morphological data, including the width of basilar part, the length, the angle between heel spur and planta pedis, and the angle between the longitudinal axis of calcaneus and heel spur.</p>

Effects of primary tumor excision on angiogenesis and pulmonary metastasis in osteosarcoma-bearing nude mice / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the effects of primary tumor excision on osteosarcoma angiogenesis and pulmonary metastasis, and explore its possible mechanism and clinical significance.</p><p><b>METHODS</b>The tumor-bearing nude mice were constructed by injection of human osteosarcoma cell suspension, and divided into primary tumor resection, amputation and normal groups. The level of VEGF and endostatin was examined by ELISA assay. The hemoglobin content in Matrigel pellets was measured with HiCN method. Pulmonary metastasis was detected with dilated-squash technique and immunohistochemical staining.</p><p><b>RESULTS</b>The serum VEGF and endostatin level was significantly decreased in the primary tumor excision group compared with that in the normal and control groups after operation, but endostatin decreased more prominently [VEGF: (71.43 +/- 9.15) pg/ml vs. (115.81 +/- 4.38) pg/ml, (111.68 +/- 12.26) pg/ml, P < 0.01; ES: (40.77 +/- 5.41) ng/ml vs. (123.18 +/- 5.94) ng/ml, (128.06 +/- 4.52) ng/ml, P < 0.01]. The HB contents in Matrigel pellets increased in the primary tumor excision group compared with that in normal and control groups [(36.55 +/- 2.35) g/L vs. (16.84 +/- 1.15) g/L, (16.29 +/- 1.10) g/L, P < 0.01]. The rate of pulmonary metastasis in tumor excision group was much higher than that in the un-excised groups (80.0% vs. 40.0% and 35.0%, P < 0.05).</p><p><b>CONCLUSION</b>The excision of primary tumor can promote osteosarcoma angiogenesis and pulmonary metastasis, so anti-angiogenic treatment after operation has instructive clinical significance in preventing tumor metastasis.</p>

Assessment of subtalar joint neutral position: a cadaveric study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Subtalar joint (STJ) neutral position is the position typically used by clinicians to obtain a cast representation of a patient's foot before fabrication of biomechanical functional orthosis. But no method for measuring STJ neutral position has been proven accurate and reproducible by different testers. This study was conducted to investigate the STJ neutral position in normal feet in cadavers.</p><p><b>METHODS</b>Twelve fresh-frozen specimens of amputated lower legs were used. Pressure-sensitive films were inserted into the anterior and posterior articulation of STJ. The contact areas for various foot positions and under axial loads of 600 N were determined based on the gray level of the digitized film. The STJ neutral positions were determined as the ankle-foot position where the maximum contact area was achieved, because the neutral position of a joint was defined as the position where the concave and convex surfaces were completely congruous.</p><p><b>RESULTS</b>In ankle-foot neutral position, the contact area of STJ was (2.79 +/- 0.24) cm(2). In the range of motion of adduction-abduction (ADD-ABD), the maximum contact area was (3.00 +/- 0.26) cm(2) when the foot was positioned 10 degrees of ABD (F = 221.361, P < 0.05). In the range of motion of dorsiflexion-plantarflexion (DF-PF), the maximum contact area was (3.61 +/- 0.25) cm(2) when the foot was positioned 20 degrees of DF (F = 121.067, P < 0.05). In the range of motion of inversion-eversion (INV-EV), the maximum contact area was (3.14 +/- 0.26) cm(2) when the foot was positioned 10 degrees of EV (F = 256.252, P < 0.05).</p><p><b>CONCLUSIONS</b>Joints, such as STJ, therefore, are not necessarily in neutral position when the ankle-foot is placed in the traditional concept of neutral position. The results demonstrate that the most approximate STJ neutral position was in the foot position of 10 degrees of abduction, 20 degrees of dorsiflexion and 10 degrees of eversion.</p>

Characteristics and surgical treatment of calcaneal fractures in aged patients / 中华创伤杂志

Objective To evaluate the effect of open reduction and internal fixation in treatment of calcaneal fractures in aged patients. Methods Between January 1997 and June 2007,37 patients (41 fractures)at a mean age of68.3 years(60-78 years)with calcaneal fractures underwent surgical operations.According to Sanders classification based on CT scanning.14 fractures were rated as typeⅡ,18 as type Ⅲ and 9 as type Ⅳ.Of all,5 fractures were treated with reconstruction plate,18 with shapeable titanic plate,4 with Y-shaped plate,12 Depuy titanic plate and 2 with AO locking titanic plate plus open reduction and internal fixation.The foot function was evaluated by X-ray,American Orthopedic Foot and Ankle Society(AOFAS)Score and Maryland Foot Score. Results A total of 27 patients (60.9%)with 31 fractures were followed up for 12-48 months(average 27.6 months),which showed that all fractures were healed,with morphous improvement of the calcanus determined by 8 parameters measured in X-ray films.The average active range of motion was 36°of plantar flexion,12°of dorsiflexion,15°of inversion,and 10°of eversion.According to Maryland Foot Score,functional foot score was excellent(90-100 points)in 16 fractures,good(75-89 points)in 13 and fair(50-74 points)in 2,with excellence rate of 94%(29/31). Conclusion Open reduction and intemal fixation can gain good clinical result in severe calcaneal fractures in aged patients with obvious dislocation of posterior articular facet.