带蒂鼻底黏膜瓣联合自体筛骨垂直板修补鼻中隔穿孔的临床观察

目的 回顾性分析带蒂鼻底黏膜瓣联合自体筛骨垂直板修补鼻中隔穿孔的疗效。方法 19例鼻中隔穿孔患者均采用鼻内镜下带蒂鼻底黏膜瓣联合筛骨垂直板修补鼻中隔穿孔,并采用纳吸棉对术后创面行填塞止血。结果19例行鼻中隔穿孔修补的患者术后随访1~3个月,17例(89.47%)患者鼻中隔黏膜均愈合良好,穿孔均修补成功,且形态恢复良好,2例(10.52%)患者因术后未能按时随访,未能观察疗效。结论 采用带蒂鼻底黏膜瓣联合自体筛骨垂直板修补鼻中隔穿孔,自体组织取材方便,经济实惠,无排异反应,带蒂鼻底黏膜瓣血供好,修补成活率高,疗效可靠。

Quantitative Histological Study on Changes of the Cortical Bones after Internal Fixation with Plates of Different Rigidity

In an effect to explore the potemtial role of bone microcirculation causing plate-induced reginal osteoporosis

EFFECT OF INTERNAL FIXATION PLATES ON MICROCIRCULATION IN UNDER-PLATE CORTICAL BONES MICROANGIOGRAPHY AND SCANNING ELECTRONMICROSCOPY

To elucidate the effect of the internal fixation plates on the local bone blood sapply, we used microangiography and scanning electron microscopy to observe the morphological changes of microcirculation in the cortical bones obtained from intact rabbit tibiae on which plates of two different stiffness had been fixed for comparison. The results indicated that both rigid stainless steel plate and less rigid methyl methacrylate plate could induce the bone microcirculation under the plate to undergo a process from early depression to late reactive recruitment. The features of the microcircuiation recruitment such as vascular number, arrangement and dilatation varied with plates of different stiffness and were more obvious in the cortex fixed by rigid stainless steel plate.

Stress-relaxation plates and the remodeling of callus and cortex under the plate in rabbits

To study the influence of a stress-relaxation plate on the remodeling of callus and cortex under the plate Methods The bilateral tibia diaphysis of New Zealand rabbit were osteotomized and fixed with stress-relaxation plate (SRP) and rigid plate (RP), respectively Polarized light microscopy and transmission electron microscopy (TEM) were used to study the remodeling of callus and the cortex under the plate from 4 to 24 weeks postoperatively Results Polarized light microscopy: the structural changes of callus and cortex beneath the plate are similar in the SRP and RP groups at the early postoperative stage, manifesting an alignment disorder of collagen fibers with a weak birefringence in the callus and absorption cavities in the cortex under the plate After the twelveth postoperative week, the SRP group showed callus starting to transform to lamellar bone and absorption cavities in the cortex under the plate becaming smaller By contrast in the RP group the absorption cavities in the callus and cortex under the plate became larger and the whole layer of cortex was cancellated TEM: the active osteoclasts appeared in both SRP and RP groups in the period from 4 to 8 weeks postoperatively In the SRP group, many functionally active osteoblasts could be seen on the surface of the bone, while in the RP group, the osteoblasts were not very active By 24 weeks postoperatively, the shape of osteocytes were normal but the number of the osteoclasts were small in the SRP group In the RP group, the osteoclasts became more active and osteocytic osteolysis was manifested Conclusions Fixation with SRP not only enhanced callus remodeling, but also abated the degree of osteoporosis in the cortex under the plate This approach may lead to an improved osteosynthetic apparatus

Experimental study of a 3D printed permanent implantable porous Ta-coated bone plate for fracture fixation

Metal plates have always been the gold standard in the clinic for internal fracture fixation due to their high strength advantages.However,high elastic modulus can cause stress shielding and lead to bone embrittlement.This study used an electron beam melting method to prepare personalized porous Ti6Al4V(pTi)bone plates.Then,chemical vapor deposition(CVD)technology coats tantalum(Ta)metal on the pTi bone plates.The prepared porous Ta-coated bone plate has an elastic modulus similar to cortical bone,and no stress shielding occurred.In vitro experiments showed that compared with pTi plates,Ta coating significantly enhances the attachment and proliferation of cells on the surface of the scaffold.To better evaluate the function of the Ta-coated bone plate,animal experiments were conducted using a coat tibia fracture model.Our results showed that the Ta-coated bone plate could effectively fix the fracture.Both imaging and histological analysis showed that the Ta-coated bone plate had prominent indirect binding of callus formation.Histological results showed that new bone grew at the interface and formed good osseointegration with the host bone.Therefore,this study provides an alternative to bio-functional Ta-coated bone plates with improved osseointegration and osteogenic functions for orthopaedic applications.

A mechanical study of personalised Ti6Al4V tibial fracture fixation plates with grooved surface by finite element analysis

Low shape matching and high stress shielding rates between bone plate and human bone are not conducive to the primary healing of fracture.In this study,taking the fracture site of the lower one‐third of human tibia as an application case,six types of personalised Ti6Al4V tibial plates with grooved surface were designed and evaluated by reverse en-gineering and finite element analysis.The results showed that the grooved design can reduce the stress shielding rate of bone plate and promote the facture healing.Among the six types of bone plates,the‘OUT-MI’bone plate has the lowest stress shielding rate and the most uniform stress distribution.Meanwhile,with the increasing tibial load during the convalescence,the average stress and maximum axial displacement of the tibial fracture surface increased,which can effectively improve the bone regeneration in the tibial fracture area.Moreover,there was no significant difference in four-point bending performance between the‘OUT-MI’bone plate and the‘STR-BE’bone plate,indicating that the mechanical properties of this bone plate were reliable.The results provide a theoretical basis for the design of fracture fixation plates on clinical treatment.

Piezoelectric-Based Smart Bone Plate for Fracture Healing Progress Monitoring

Fracture healing progress monitoring techniques attract global research attention due to the importance of selecting the timing of removing the fixation device.To this end,in this research,we present a piezoelectric-based smart internal fixation device,in which a piezoelectric sandwich structure is laminated to the surface of a bone plate.In the content,we explain the reasons for utilizing piezoelectric films,elaborate the mechanism of fracture monitoring,and introduce the mechanical parameters of the sensor.The simulation and experimental results show that the electrical output of the device is associated with the elastic modulus of the filler between the tested broken bones when the working load is maintained,indicating that the bone recovery progress could be successfully detected by the developed technique.

Influence of Medial Support Screws on the Maintenance of Fracture Reduction after Locked Plating of Proximal Humerus Fractures

Background： Technical aspects of the correct placement of medial support locking screws in the locking plate for proximal humerus fractures remain incompletely understood. This study was to evaluate the clinical relationship between the number of medial support screws and the maintenance of fracture reduction after locked plating of proximal humerus fractures. Methods： We retrospectively evaluated 181 patients who had been surgically treated for proximal humeral fractures （PHFs） with a locking plate between September 2007 and June 2013. All cases were then subdivided into one of four groups as follows： 75 patients in the medial cortical support （MCS） group, 26 patients in the medial multiscrew support （MMSS） group, 29 patients in the medial single screw support （MSSS） group, and 51 patients in the 11o medial support （NMS） group. Clinical and radiographic evaluations included the Constant-Murley score （CM）, visual analogue scale （VAS）, complications, and revision surgeries. The neck-shaft angle （NSA） was measured in a true anteroposterior radiograph immediately postoperation and at final follow-up. One-way analysis of variance or KruskaI-Wallis test was used for statistical analysis of measurement data, and Chi-square test or Fisher＇s exact test was used for categorical data. Results： The mean postoperative NSAs were 133.46°± 6.01°, 132.39° ± 7.77°. 135.17° ± 10.15°, and 132.41° ± 7.16° in the MCS, MMSS, MSSS, and NMS groups, respectively, and no significant differences were found （F = 1.02, P= 0.387）. In the final follow-up, the NSAs were 132.79° ±6.02°, 130.19° ± 9.25°, 131.28° ± 12.85°, and 127.35° ± 8.50° in the MCS, MMSS, MSSS, and NMS groups, respectively （F = 4.40, P = 0.008）. There were marked differences in the NSA at the final follow-up between the MCS and NMS groups （P = 0.004）. The median （interquartile range [IQR]） NSA losses were 0.0° （0.0-1.0）°, 1.3° （0.0-3.1）°, 1.5° （ 1.0-5.2）°, and 4.0° （ 1.2 -7.1 ）° in the MCS, MMSS, MSSS, and NMS groups, respectively （H = 60.66, P 〈 0.001 ）. There were marked differences in NSA loss between the MCS and the other three groups （MCS vs. MMSS, Z = 3.16, P = 0.002; MCS vs. MSSS, Z = 4.78, P 〈 0.001; and MCS vs. NMS, Z = 7.34, P 〈 0.001）. There was also significantly less NSA loss observed in the MMSS group compared to the NMS group （Z = -3.16, P = 0.002）. However, there were no significant differences between the MMSS and MSSS groups （Z = -1.65, P = 0.225） or the MSSS and NMS groups （Z =- 1.21, P = 0.099）. The average CM scores were 81.35 ± 9.79, 78.04± 8.97, 72.76 ± 10.98, and 67.33 ± 12.31 points in the MCS, MMSS, MSSS, and NMS groups, respectively （F = 18.68, P 〈 0.001）. The rates of excellent and good CM scores were 86.67%, 80.77%, 65.52%, and 43.14% in the MCS, MMSS, MSSS, and NMS groups, respectively （ X^2 = 29.25, P 〈 0.001 ）. The median （IQR） VAS scores were 1 （0-2）, l （0 2）,2 （ 1-3）, and 3 （1-5） points in the MCS, MMSS, MSSS, and NMS groups, respectively （H = 27.80, P 〈 0.001）. Functional recovery was markedly better and VAS values were lower in the MCS and MMSS groups （for CM scores： MCS vs. MSSS, P 〈 0.001 ; MCS vs. N MS. P 〈 0.001; MMSS vs. MSSS, P= 0.031 and MMSS vs. NMS, P 〈 0.001 and for VAS values： MCS vs. MSSS, Z=3.31, P = 0.001： MCS vs. NMS, Z = 4.64, P 〈 0.001; MMSS vs. MSSS, Z = -2.09, P = 0.037： and MMSS vs. NMS, Z=-3.16, P = 0.003）.Conclusions： Medial support screws might help enhance mechanical stability and maintain fracture reduction when used to treat PHFs with medial metaphyseal comminution or malreduction.

Comparative study of perpendicular versus parallel double plating methods for type C distal humeral fractures

Background Double plate osteosynthesis is the standard treatment for intra-articular fractures of the distal humerus.However,there is still controversy concerning dual plate positions in terms of providing optimal stability.The purpose of this retrospective study was to compare the clinical outcomes in patients with type C intra-articular distal humeral fractures using perpendicular and parallel plating methods.Methods Between March 2008 and June 2011,a total of 45 patients with type C distal humerus fractures were treated using two different dual plating methods.Of them,24 patients were treated by perpendicular plating （group Ⅰ） and 21 patients were treated by parallel plating （group Ⅱ）.The surgical time,blood loss,and union time were compared between the two groups.The fiexion-extension arc,the total range of flexion and extension at the end of follow-up were compared between the two groups.The Mayo Elbow Performance Score （MEPS） was used to determine the elbow functional results.Results All patients were followed up.The mean duration of follow-up was 16 months （range 12-25 months） in group Ⅰ and 15.5 months in group Ⅱ （range 12-25 months）.There were no significant differences in the surgical time,blood loss,and the bone union time between the two groups.In group Ⅰ,the mean elbow flexion-extension arc was 101° and the mean MEPS was 85 points.The rate of excellent and good results was 87.5%.In group Ⅱ,the mean flexion-extension arc was 100° and the mean MEPS was 86.1 points.The rate of excellent and good results was 90.5%.There were no significant differences in the MEPS,flexion-extension arc,and the total range of flexion and extension between the two groups.Conclusions Perpendicular and parallel plate configurations with the appropriate surgical techniques can provide anatomical reconstruction and stable fixation of type C intra-articular distal humeral fractures and allow early mobilization of the elbow after an operation.The occurrence of post-operative elbow stiffness can be reduced and good outcomes can be obtained.