Analysis Of The Effect Of 3D Printing Technology In The Fixation Of High Complex Rib Fracture And Total Thoracoscopic Memory Alloy Rib Coaptation Plate Fixation Of Posterior Rib Fracture

With the rapid development of all aspects of society,the number of trauma patients is increasing,and chest wall trauma is very common all over the world.According to data from many countries,chest trauma accounts for 9%to 25%of all trauma cases,of which rib fracture is the most common trauma,accounting for 50%to 80%of chest trauma.China has a large population and conservative estimates put the number of rib fractures at 1.5 to 2 million per year.Multiple rib fractures,especially flail chest,can lead to a variety of complications,affecting prognosis and life treatment,and even life-threatening.With the development of internal fixation equipment and the continuous in-depth research and exploration of experts at home and abroad,the advantages of surgical fixation of rib fracture have been widely recognized.And the surgical fixation of rib fractures is becoming more minimally invasive.The rib fractures meet the following requirements are classified as high complex rib fractures:1)has one to three fractures in the 2nd to 4th ribs;2)each fracture site has 3 fracture segment;3)the length of the middle fracture segment ≤5 cm;4)the presence of costal cartilage fracture.Surgery of high complex rib fractures often requires extensive dissection of chest wall muscle layer,long incision and large injury.At present,there is no optimal minimally invasive surgical fixation treatment.We attempted to premode the locking plate and plan the operation based on 3D printed rib models,as well as the application of framework internal fixation techniques in minimally invasive surgery of high complex rib fractures.Postoperative observation and follow-up were carried out to further evaluate the feasibility and clinical efficacy of the surgical scheme.With the maturity and popularization of thoracoscopic technology,many scholars have tried to fix rib fracture through pleural cavity.The posterior ribs in the covered area of scapula and interscapular area are covered by multiple muscles.Besides,they are affected by the anatomical structure,and the operation space is narrow,so it is difficult to operate through the conventional chest wall incision.Total pleural endoscopic fixation has the advantages of minimally invasive and aesthetic.However,there are adverse factors,such as difficult reduction of fracture end,limited selection and molding of internal fixation devices,and imprecise placement of fixation devices in total thoracoscopic surgical fixation of rib fracture.A memory alloy rib coaptation device has been developed and designed by our country.This kind of device eliminates the drilling of the rib,temporary fixation of the fractured ends,and screw fixation required by the locking plate.Nevertheless,there are some problems in this method,such as poor fitting between the fixator and the rib and poor reduction of the broken rib and falling off of the internal fixator.In view of the above problems,we tried to select the most suitable devices and carefully plan the operation and fixation plan according to the preoperative 3D rib model.To investigate the clinical effect of 3D printing technology in the fixation of posterior rib fracture with thoracoscopic memory alloy clasping device.Current studies on the timing of surgical stabilization of rib fractures are based on the data of conventional transthoracic surgery.However,there are significant differences in the structure and histological characteristics of the broken ribs separated by chest wall and pleural cavity.Therefore,this study investigated the relationship between the operative timing and the difficulty of dissociation of the fractured end of the rib under complete video-assisted thoracoscopic surgery.Part One Application of 3D printing and framework internal fixation technology for high complex rib fracturesObjective:To explore the clinical effect of 3D printing combined with framework internal fixation technology on the minimally invasive internal fixation of high complex rib fractures.Methods:Total 16 patients with high complex rib fractures were included in the study.Before the procedure,the 3D rib model was reconstructed based on the thin-layer chest CT scan.According to the 3D model,the rib locking plate was pre-shaped,and the preoperative planning were made including the direction of the locking plate,the location of each nail hole and the length of the screw.During the operation,the locking plate was inserted from the sternum to the outermost fracture lines of ribs with screws at both ends.In addition,the locking plate was used as the frame to sequentially reduce the middle fracture segment and fix with screws or steel wires.Chest x-rays or chest CT scans after surgery were used to assess the ribs recovery.All patients were routinely given non-steroidal anti-inflammatory drugs(NSAIDS)for analgesia,and the pain level was evaluated using numerical rating scale(NRS).Results:The preoperative planning according to the 3D printed rib model was accurate.The reduction and fixation of each fracture segment were successfully completed through the framework internal fixation technology.No cases of surgical death,and postoperative chest pain was significantly alleviated.Five to 10 onths follow up demonstrated neither loosening of screws,nor displacement of fixtures among patients.The lungs of each patients were clear and in good shape.Conclusion:The application of 3D printing combined with framework internal fixation technology to the high complex rib fractures is beneficial for restoring the inherent shape of the thoracic cage,which can realize the accurate and individualized treatment as well as reduces the operation difficulty.Part Two Effect of preoperative 3D printing technique on the fixation of posterior rib fractures with memory alloy rib coaptation plate via video-assisted thoracoscopic surgeryObjective:Complete video-assisted thoracoscopic surgery for rib fractures has attracted the attention of experts at home and abroad.Especially for complex posterior rib fractures,this method has more advantages.However,there are still some factors such as difficult reduction of fracture,limited selection and molding of fixator,and poor placement of fixator in pleural cavity.3D printing technology,which can accurately simulate a patient’s specific anatomy,has made great strides in many medical fields.However,the effect of 3D printing technology in complete video-assisted thoracoscopic surgery for rib fractures has never been mentioned in the literature.The purpose of this study was to investigate the effect of preoperative 3D printing on posterior rib fractures with memory alloy rib coaptation plate via complete video-assisted thoracoscopic surgery.Methods:This study retrospectively analyzed the records of patients with posterior rib fracture at our hospital from September 2019 to November 2021.And these patients underwent complete thoracoscopic surgical fixation of their posterior rib fractures with memory alloy rib coaptation plate.A total of 21 patients were included.Patients were divided into two groups,3D printing and non-3D printing,according to whether the ribs had been 3D printed before surgery.The average fixation time of each fracture,the fall off of the fixation device and the unsatisfactory reduction of the fracture end were compared between the two groups.Results:Among the 21 patients included,7 were in the 3D printing group and 14 were in the non-3D printing group.In the 3D printing group and the non-3D printing group,the average fixation time per location was 24.9 ±6.3min and 28.4 ± 8.5 min,respectively.Although the 3D printing group had a shorter average fixation time at each location than the non-3D printing group,there was no statistically significant difference between the two groups(P>0.05).In the non-3D printing group,13 of the 35 fracture sites were poorly fixed;and in the 3D printing group,only 2 of 23 fractures were poorly fixed.The defect rate of fracture fixation in 3D printing group was significantly lower than that in non-3D printing group(8.7%vs 37.1%,P<0.05).The difference between the two groups was statistically significant.But,no memory alloy rib coaptation plate was completely detached into the pleural cavity in both groups.Conclusion:In this study,3D printing technology was used to make the rib model before surgery for the fixation of the posterior rib fracture with memory alloy rib coaptation plate under thoracoscopy.In addition,according to the 3D printed rib model,precise preoperative planning of surgery and selection of memory alloy rib coaptation plates can help reduce the incidence of poor fracture fixation and achieve accurate and individualized treatment.Part Three Effect of the timing of complete video-assisted thoracoscopic surgery for rib fracture on the separation of the tissue around the rib fracture end.Objective:At present,there is a complete thoracoscopic fixation of rib fracture using memory alloy rib coaptation plate through pleural cavity developed in China,which has achieved certain positive results.This procedure requires dissection of the tissue around the rib fracture ends to expose the broken ribs.The purpose of this study was to investigate the relationship between the timing of the operation and the difficulty of dissecting the fractured rib.To provide reference for the choice of operation time.Methods:This study retrospectively analyzed the records of patients with posterior rib fracture at our hospital from September 2019 to November 2021.And these patients underwent complete thoracoscopic surgical fixation of their posterior rib fractures with memory alloy rib coaptation plate.A total of 21 patients were included.According to the time from injury to operation,patients were divided into two groups:<7d group and>7d group,and the average dissection time of fracture end in operation was compared between the two groups.Results:In the 21 patients included,the time from injury to rib fracture fixation was 2-15d,with a mean time of 7.0±4.6 d.The ≤7d group and>7d group included 13 and 8 patients,respectively.The median number of fixed sites per patient in the two groups was 3.0(IQR,1-3)and 2.5(IQR,2-4),respectively.The the average dissection time of each rib fracture in ≤7d groupwas shorter than that in>7d group,the difference was statistically significant(P<0.05).Conclusion:The results of this study suggest that when the rib fracture is fixed with memory alloy rib coaptation plate via video-assisted thoracoscopic surgery,the fractured end of the rib fracture is more easily dissociated and exposed ≤7d after injury,and the operation is relatively simple,which is beneficial to shorten the operation time.