Objective To study the value of three-dimensional (3D) visualization and virtual surgery system in piggyback liver transplantation. Methods Two patients who suffered from choledocholithiasis were scanned by 64-slice spiral CT and the data were collected. The segmentation of the hepatic CT images was carried out. The 3D model of the liver and the intrahepatic vessels was reconstructed, and was imported to the FreeForm Modeling System in STL format for smoothing and modifying. Piggyback liver transplantation was simulated with the force-feedback equipment (PHANToM). Results The reconstructed 3D model of the liver was vivid, and the process of the virtual piggyback liver transplantation was verisimilar. Conclusions The 3D model of the liver enables the simulation of piggyback liver transplantation. It can reduce the risk and complications of the surgery, and enhance the communication between doctor and patient through designing surgical plan and demonstrating visualized operation before surgery. Virtual liver transplantation is also helpful during the training of medical workers.

Objective:To explore the efficacyof direct anterior approach (DAA) combined with direct posterior approach (DPA) for the treatment of Pipkin IV fracture.Methods:Data of 18 patients with Pipkin IV fracture treated through DAA combined with DPA from January 2016 to April 2019 was retrospectively analyzed. There were 13 males and 5 females, with an average age of 43.2 years (range,19-56 years). Fractures were caused by traffic accident in 15 and by falling in 3. The fracture lines of 13 cases were located below the fovea of the femoral head and 5 cases were located above the fovea. According to Letournel-Judet classification for acetabular fractures, there were 14 cases of posterior acetabular wall fractures, 2 cases of posterior wall fractures involving posterior column, and 2 transverse plus posterior wall fractures. The operation was performed through DAA approach to treat the femoral head fractures, and DPA approach was used to treat acetabular fractures. Radiographs and CT scans of the pelvis were reexamined after surgery, and fracture reduction, healing, and complications such as femoral head necrosis, sciatic nerve injury, superior gluteal neurovascular injury and heterotopic ossification were evaluated. Quality of acetabular reduction was evaluated according to the criteria proposed by Matta. Thompson-Epstein scoring system was used to evaluate hip function.Results:The average operation time was 133 min (range, 75-205 min). And the average blood loss was 371 ml (range, 240-600 ml). All 18 patients were followed up for 6 to 36 months, with an average period of 15.7 months. All fractures healed 10 to14 weeks after surgery. Three patients had symptoms of sciatic nerve injury after the injury, who recovered 6 to 12 weeks after the operation. All femoral head fractures were reduced. According to Matta criteria of reduction quality, anatomic reduction was gained in 13 cases, and satisfactory reduction was obtained in 3 cases, while unsatisfactory reduction was found in 2 cases, and the overall satisfactory rate was 88.9%(16/18). Two patients had Brooker I level heterotopic ossification. There was no iatrogenic vascular injury, avascular necrosis of femoral head, infection, internal fixation failure or other complications. According to the Thompson-Epstein scoring system at the latest follow-up, the functional results of the affected hip were excellent in 7 cases, good in 8, fair in 2 and poor in 1.Conclusion:Treatment of Pipkin IV fractures through DAA combined with DPA approach reduces surgical invasion. And it can directly reduce and fix the femoral head and posterior acetabular fracture, and protect the important structures such as the arteriae circumflexa femoris medialis, sciatic nerve and lateral femoral cutaneous nerve, and reduce the occurrence of complications such as femoral head necrosis and heterotopic ossification. Therefore, DAA combined with DPA is aneffective method for the treatment of Pipkin IV fractures.

Objective:To investigate the efficacy of intelligent visualization system (HoloSight Intelligent Visualization System) assisted reduction and screw fixation in the treatment of elderly pelvic fragility fracture.Methods:From January 2016 to December 2022, clinical data of 18 elderly patients aged over 75 years with pelvic fragility fractures surgically treated by our team were retrospectively analyzed. Among them, 11 cases were treated with closed reduction and hand-inserted percutaneous screw fixation to fix the posterior pelvic ring (control group), and 7 cases were treated with the assistance of the HoloSight intelligent visualization system for reduction and minimally invasive fixation (experimental group). In the control group, there were 3 males and 8 females with an age range of 75-94 years (mean age, 82±12 years). The pelvic fractures were classified as FFP type IIIa in 5 cases, IIIb in 2 cases, IIIc in 3 cases, and IV in 1 case. In the experimental group, there were 1 male and 6 females with an age range of 76-100 years (mean age. 83±14 years). The pelvic fractures were classified as FFP type IIIa in 4 cases, IIIc in 2 cases, and IV in 1 case. The surgical time, blood loss, effective intraoperative fluoroscopy times, fracture reduction quality (according to Matta standards), visual analogue scale (VAS), limb function rehabilitation (Majeed score) and postoperative complications were recorded and evaluated in both groups.Results:All patients underwent surgery successfully and were followed up for 6 months to 3 years(12 months on average), all pelvic fractures healed. Among the 7 cases of experimental group, a total of 13 screws were placed, and the adjustment times of guide pin for each screw were 3±1 times (range, 1-5 times), while 18 screws of the control group with the adjustment times of 7±2 times (range, 4-10 times), statistical difference was present ( t=6.99, P<0.001). The surgical time in experimental group (63±12 min) was shorter than that in control group 88±23 min, while effective intraoperative fluoroscopy times in experimental group (9±3 times) was less than that in control group (35±7 times), the difference were both statistically significant ( t=2.69, P=0.016; t=9.22, P<0.001). The intraoperative blood loss was 38±12 ml in the experimental group and 55±26 ml in control group, with no significant difference ( t=1.61, P=0.127). According to Matta's reduction criteria after surgery, the results of experimental group were excellent in 4 cases, good in 2, and fair in 1, while the result of control group were excellent in 5 cases, good in 3, fair in 2, and poor in 1. At the last follow-up, among the patients in experimental group, the Majeed score was 84±11, excellent in 3 cases, good in 2, and fair in 2. In control group, the score was 79±17, with excellent in 5 cases, good in 3, fair in 3. No statistical difference was observed in two groups ( t=0.69, P=0.501). The VAS was 6.4±2.6 preoperatively and 2.4±0.8 postoperatively in the experimental group, while in the control group was 6.9±3.1 preoperatively and 2.7±1.3 postoperatively, the data suggested an improvement in both groups ( t=3.89, P=0.002; t=4.14, P<0.001), while no statistical significant was observed in two groups at last follow-up ( t=0.55, P=0.593). Two cases of experimental group had loosening or withdrawal of the fixation screws in 9 and 12 months, but the fractures healed. Four cases of control group loose fixation screws in 4, 6, 9, and 12 months, two cases underwent revision surgery and other two cases healed. Conclusion:Intelligent visualization system assisted reduction and screw fixation in the treatment of elderly pelvic fragility fractures have the advantages of good reduction, accurate nail placement, less bleeding, less effective fluoroscopy, which improves the safety of surgery.

Objective: To explore surgical technique and clinical results of the direct posterior approach (DPA) for acetabular fractures involving posterior column, posterior wall, or posterior column and wall. Methods: From January 2016 to June 2017, data of 10 cases (7 males, 3 females, an average age of 37 years, ranging from 17 to 54 years) with posterior acetabular fractures treated by the DPA were retrospectively analyzed. Fractures were caused by traffic accident in 6 cases and by falling in 4 cases. According to Letournel-Judet classification of acetabular fractures, there were 6 cases of posterior acetabular wall fractures, 4 cases of posterior wall fractures involving posterior column. A straight skin incision was made from the middle of the line between the posterior margin of the tip of the femoral greater trochanter and the posterior superior iliac spine, to the posterior margin of the femoral greater trochanter. The gluteus maximus muscle was cleaved longitudinally. A view of the area from hip capsule to the superior margin of the greater sciatic foramen was obtained by entering along the interspace of the gluteus medius and pyriformis muscle, and the superior gluteal neurovascular bundle was protected. Acetabular posterior column and posterior wall fractures were reduced and fixed under direct vision. The fracture reduction, fracture healing, femoral head necrosis, sciatic nerve injury, superior gluteal neurovascular injury and heterotopic ossification were evaluated by the postoperative X-ray and CT examination. The function of hip joint was assessed by the Merle d’Aubigné-Posteal score modified by Matta. Results: The average operative incision length was 9.6 cm (range, 8-11 cm). The average operation time was 50 min (range, 35-80 min). The average blood loss was 310 ml (range, 200-440 ml). The time of follow-up was 12-30 months. All the patients were healed within 8-12 weeks without any complications such as superior gluteal nerve injury, superior gluteal vessel injury, or sciatic nerve injury. One case of acetabular posterior wall and posterior column fracture with posterior dislocation of hip joint, suffered from femoral head necrosis at the 9th months after surgery, which was treated by total hip arthroplasty and was recovered one year after surgery. In one case of actebular posterior wall and posterior column fracture, heterotopic ossification occurred 3 month after operation, without any special treatment and the hip joint activity was not affected at the follow-up of 15 months after surgery. During the 12-month follow-up after surgery, the Merle d’Aubigné-Postel score modified by Matta was 13-18, among which there were excellent in 6 cases, good in 2, acceptable in 2, with an overall excellent and good rate of 80% (8/10). Conclusion The direct posterior approach for posterior acetabular fractures can obtain satisfactory clinical results. The advantages of the DPA include decreasing trauma, shortening operation time, reduing blood loss and decreasing risks of iatrogenic injury to the gluteus medius muscle, the external rotators, the arteriae circumflexa femoris medialis and sciatic nerves as well as reducing and fixing the fractures under direct vision. Thus, the DPA is a relatively safe surgical approach for acetabular posterior wall/column fracture.

Objective:To investigate the effectiveness of the modified Bikini approach in the fixation of acetabular fracture with an integrated wing-shaped anatomical locking plate.Methods:A retrospective study was conducted to analyze the data of 54 patients with acetabular fracture who had been treated at Department of Trauma Orthopedics, Orthopedic Medical Center, The Third Hospital Affiliated to Southern Medical University from May 2017 to June 2021. The patients were divided into 2 groups based on different surgical approaches: an observation group [26 cases, 6 males, 20 females; aged 40.0 (29.8, 46.8) years] treated with fixation with an integrated wing-shaped anatomical locking plate through the modified Bikini approach, and a control group [28 cases, 10 males, 18 females; aged 34.5 (24.0, 43.5) years] treated with fixation with an integrated wing-shaped anatomical locking plate through the lateral-rectus approach. The incision length, operation time, intraoperative bleeding, length of hospital stay, quality of postoperative fracture reduction, visual analog scale (VAS) for pain, hip function, Vancouver Scar Scale (VSS) and Patient and Observer Scar Assessment Scale (POSAS) were compared between the 2 groups.Results:The differences in the preoperative general data between the 2 groups were not statistically significant, indicating comparability ( P>0.05). There were no statistically significant differences between the 2 groups either in terms of incision length, operation time, intraoperative bleeding, or hospital stay ( P>0.05). The 2 groups were not significantly different in the excellent/good rate of fracture reduction [100.0% (26/26) versus 92.9% (26/28)], VAS at 1 month postoperation [2.0(1.0, 3.0) versus 2.0(1.0, 3.0)], or the modified Merle d'Aubigné and Postel hip score at 12 months postoperation [13.5(12.3, 14.8) versus. 14.0(13.0, 15.0)] ( P>0.05). However, the VSS [4.50(4.00, 6.00)] and POSAS (29.85±10.05) at 12 months postoperation in the observation group were significantly lower than those in the control group [6.50(5.00, 8.25) and 37.11±11.75] ( P<0.05). Conclusion:In the fixation of acetabular fracture with an integrated wing-shaped anatomical locking plate, the modified Bikini approach can not only achieve as fine early clinical efficacy as the lateral-rectus approach, but also demonstrate the aesthetic advantages of smaller incision scar and more hidden incision.

Objective: To evaluate clinical efficacy and surgical techniques of customized variable-angle locking acetabular wing plates in treatment of complex acetabular fractures in the elderly through the lateral-rectus approach. Methods: Data of 11 elder patients of complex acetabular fractures (mean age 75 y, range: 60-93 y; 8 males, 3 females) admitted to our department from March 2016 to March 2017 were retrospectively analyzed. According to Judet-Letournel classification of acetabular fractures, there were 2 cases of anterior column and posterior hemitransverse fractures, 9 cases of both-column fractures. The customized variable-angle locking acetabular wing plates were designed by mimics software and then produced before surgery. During the operation, the customized variable-angle locking acetabular wing plate was applied to reduction and fixation via the anterior lataral-rectus approach. The effect of fracture reduction was assessed by Matta's criteria. The clinical effect was assessed by Harris Hip score and the modified Merle d' Aubigné-Postal score at the 6th month of postoperative follow-up. Results: The average time of designing and producing customized variable-angle locking acetabular wing plates was 4 d (3-5 d), the average operation time was 95 min (45-150 min), and the average intraoperative bleeding was 600 ml (250-1 400 ml). All patients were followed up, with an average follow-up of 18 m (6-24 m). All fractures were healed, with an average healing time of 8 weeks (6-12 weeks). Reduction quality: excellent in 8 cases, good in 2 cases, poor in 1 case, with an overall excellent and good rate of 90.9%. The result of Harris Hip scoring: excellent in 7 cases, good in 3 cases, and acceptable in 1 case, with a total excellent and good rate of 90.9%; Modified Merle d' Aubigné-Postal soring: excellent in 6 cases, good in 3 cases, and acceptable in 2 cases, with an overall excellent and good rate of 81.8%. There were 2 cases of obturator nerve injury, 1 case of fat liquefaction of incision, 3 cases of traumatic hip arthritis. During the follow-up, no complications such as ectopic ossification, plate fracture and screw loosening were found. Conclusion The customized variable-angle locking acetabular wing plates in treatment of complex acetabular fractures in the elderly via the lateral-rectus approach can achieve satisfactory reduction and firm fixtation.

Objective To explore the efficacy of the anterior lateral-rectus approach combined with preoperative simulation assisted by 3D printing for treatment of acetabular fractures in the elderly.Methods A total of 52 elderly patients with acetabular fracture were admitted to Department of Orthopaedics and Trauma,The Third Affiliated Hospital to Southern Medical University from January 2014 to December 2017.They were 36 males and 16 females,with an average age of 71.6 years (from 65 to 88 years).According to the Judet-Letournel classification,there were 5 anterior column fractures,6 transverse fractures,18 anterior and posterior hemi-transverse fractures,and 23 both-column fractures.For all cases a preoperative surgical simulation was implemented based on their 3D-printed acetabular models.A pre-bent reconstruction plate or a custom acetabular aliform plate was placed to fixate the fracture after reduction via the anterior lateral-rectus approach.The reduction quality,healing time,function of affected hip and complications were recorded.Results The operation time for this cohort ranged from 85 to 138 min (average,102 min);the intraoperative bleeding ranged from 280 to 750 mL(average,520 mL).Perioperatively,implant failure,wound infection or symptomatic lower extremity phlebothrombosis was observed in none of the patients.According to the Matta radiological evaluation,the postoperative reduction was rated as excellent in 40 cases,as good in 7 and as poor in 5 (an excellent and good rate of 90.4％).All cases were followed up for 6 to 18 (mean,10.6 months).All the acetabular fractures united after 8 to 20 weeks (average,12 weeks).According to the modified Merle d'Aubigne-Postal scoring at the final follow-up,the function of affected hip was categorized as excellent in 29 cases,as good in 12 and as fair in 11 (an excellent and good rate of 78.8％).Walking pain was experienced by 5 patients 6 months after operation,diagnosed by imaging examination as traumatic arthritis of the hip joint.Follow-ups observed no such complications as screw loosening or heterotopic ossification.Conclusion In the treatment of acetabular fractures in the elderly,the anterior lateral-rectus approach combined with preoperative simulation assisted by 3D printing can achieve effective reduction and fixation,decrease intraoperative hemorrhage,shorten operation time and reduce such complications as screw loosening caused by osteoporosis.

Objective:To explore the surgical indications, techniques and methods of closed reduction and minimally invasive fixation for the treatment of pelvic fractures of Tile C2 and C3, and evaluate the clinical efficacy.Methods:A retrospective analysis of the data of 20 cases with Tile C2 and C3 pelvic fractures treated with closed reduction and minimally invasive fixation from January 2016 to July 2019. There were 7 males and 13 female, with an average age of 35.6±14.6 years (range 12-60 years). The time from injury to operation was 5-30 d, with an average of 19.3±7.1 d. Tile classification of pelvic fracture: 13 cases of C2 type and 7 cases of C3 Type. 2 cases were complicated with ipsilateral or bilateral lumbosacral nerve injury. Classification of nerve injury: 2 cases were partial injury, British Medical Research Council (BMRC) Grade M3. The operation is treated with closed reduction and minimally invasive fixation. First, the side with obvious displacement is fixed on the operating table with a pelvic reduction frame, and the side with less displacement is traction. After reduction, insert S 1 and S 2 sacroiliac screw guide-pin on this side to the contralateral sacral fracture. And then change the traction, fix the reset side on the operating table, change the side with obvious traction displacement, after the reset is ideal, pass the inserted guide-pin through the contralateral sacroiliac joint to the outer iliactable. Then insert the sacroiliac screw. The patients complicated with acetabular fracture were reduced and fixed by the corresponding approach, and the anterior ring was fixed by INFIX. The operation time, intraoperative bleeding volume and postoperative complications were recorded. The quality of fracture reduction was evaluated by Matta's criteria, and the clinical effect was evaluated by Majeed score. Results:All the 20 patients successfully completed the operation. The operation time was 105-210 min, with an average of 167.00±31.21 min. The intraoperative bleeding volume was 30-100 ml, with an average of 82.00±5.36 ml. Postoperative X-ray and CT showed that the fracture was reduced and fixed. According to the Matta's criteria, the reduction quality was rated as excellent in 14 cases, good in 4 case, fair in 2 case, with an excellent and good rate of 90%. Two patients showed symptoms of lateral femoral cutaneous nerve injury without other complications related to surgery. Follow-up for 1 to 4 years, the fractures healed, and the healing time was 6 to 12 weeks. According to the Majeed score, the result was rated as excellent in 18 cases, good in 2 case, with an excellent and good rate of 100%.Conclusion:Closed reduction and minimally invasive fixation for the treatment of pelvic fractures of type C2 and C3, with the characteristics of less damage and good results, will become a trend in the treatment of pelvic fractures.

Objective:To investigate the clinical efficacy of lateral-rectus approach(LRA) for vertical shear fracture of pelvis combined with lumbosacral plexus nerve injury.Methods:A retrospective study was conducted of the 37 patients who had been treated at Department of Orthopaedics, The Third Affiliated Hospital to Southern Medical University for vertical shear pelvic fracture combined with lumbosacral plexus nerve injury from August 2010 to August 2018. They were 25 males and 12 females, aged from 18 to 61 years (mean, 36.2 years). By the Tile classification, there were 31 cases of type C1.3, 5 cases of type C2 and one of type C3. LRA was used in all the patients to explore and release the lumbosacral plexus nerve and to reduce the sacral fracture. The posterior ring was fixated with an anterior iliac plate or sacral screws before fixation of the anterior ring and treatment of the acetabular fracture. The operation time, intraoperative bleeding volume, quality of fracture reduction, fracture union time and recovery of nerve and muscle strength were recorded.Results:For this cohort, the operation time ranged from 105 to 228 minutes (mean, 155.0 minutes) and the intraoperative bleeding volume from 680 to 2, 440 mL (mean, 1, 070 mL). Thefollow-up time ranged from 1 to 8 years (average, 2 years). According to the Matta criteria, the quality of fracture reduction was evaluated as excellent in 21 cases, as good in 12 cases and as fair in 4 cases, giving an excellent and good rate of 89.2%. Follow-ups revealed reduction loss in 4 patients, nonunion and reduction loss in one patient and bony union in the other 32 patients after 8 to 12 weeks (mean, 10.1 weeks). According to the criteria by the Nerve Injuries Committee of the British Medical Research Council (BMRC), the recovery of nerve and muscle strength achieved M5 (full recovery of neurological symptoms) in 22 cases, M4 (fine recovery of neurological symptoms) in 7 cases, M1, M2 and M3 (partial recovery of neurological symptoms) in 5 cases, and M0 (no recovery of neurological symptoms) in 3 cases.Conclusion:LRA is an ideal surgical approach for treatment of pelvic vertical shear fractures complicated with lumbosacral plexus nerve injury, because it can well expose the medial pelvic joint from the sacroiliac joint to the symphysis pubis, allow direct release of the lumbosacral plexus nerve compressed and stretched, and, together with traction of the lower limbs, lead to satisfactory fracture reduction.

Objective:To investigate the application of three-dimensional (3D) image fusion technique of pelvic enhanced CT and magnetic resonance neurography (MRN) on the patients of pelvic fractures with lumbosacral plexus injury.Methods:From January 2019 to December 2020, 15 patients (11 males, 4 females, mean age 26.67±11.34 of pelvic fracture (AO classification C1.3 of 11 cases, C2 of 2 cases, C3 of 2 cases) with lumbosacral plexus injury underwent 3D image fusion of pelvic enhanced CT and MRN. All patients exhibited lower limb nerve dysfunction after injury. The preoperative muscle strength were evaluated by British Medical Research Council (BMRC) criteria: grade 0 in 2 cases, grade 1 in 5, grade 2 in 7 and grade 3 in 1. Physical examination and enhanced CT combined with MRN 3D image fusion technology were used to accurately determine the injury site of lumbosacral plexus nerve, fracture displacement, and the direction of blood vessels and ureters, and develop corresponding surgical plans. The neurological functions were measured in post-operation follow-up.Results:All 15 operations were successfully completed and the site of lumbosacral plexus injury during operation was consistent with preoperative fusion image, and inconsistency of injury characteristic in 4 patients (4/15, 27%). Among the 6 cases of laparoscopic surgery, 2 cases were changed to open surgery because of the difficulty of nerve decompression. The average time of 4 cases of laparoscopic surgery was 116.27±26.46 min and intraoperative blood loss was 102.50±79.32 ml. The average time of 11 cases of open operation was 123.64±38.28 min, and intraoperative blood loss was 713.64±393.12 ml. For the opening operations, 9 cases were successfully decompressed, and nerve disruption was observed in 2 patients. All 15 patients were followed up. The average follow-up time was 9.33±2.19 months. The radial bony healing was observed in each case at the end of follow-up, mean healing time was 5.03±1.04 months (range, 3-6 months). In addition, patients' muscle strength recovered, 8 cases of grade 5, 3 cases of grade 4, 1 case of grade 3, 1 case of grade 2, and 2 cases of grade 0 after surgery. The difference was statistically significant ( Z=3.27, P<0.001). On the other hand, in sensory function assessment, there were 8 cases of grade S5, 1 case of grade S4, 3 cases of grade S3, 1 case of grade S2 and 2 cases of grade S0 after surgery. Conclusion:3D image fusion of enhanced CT and MRN can accurately locate and characterize pelvic fractures combined with lumbosacral plexus injury before surgery, accurately guide the formulation of surgical plan, and reduce surgical trauma and related complications.