Objective To investigate the effects of mefformin on the differentiation of osteoclastas well as relative mechanism.Methods Raw264.7 cells from the murine macrophage cell line was used.Receptor activator of NF-κB ligand (RANKL) was used to stimulate osteoclast differentiation from Raw264.7 cells.Osteoclast differentiation was assessed by tartrate-resistant acid phosphatase (TRAP) and actin fluorescence staining and counting the TRAP-positive cells after exposure to different concentrations of mefformin (0 μmol/L,400 μmol/L,800 μmol/L and 1000 μmol/L) or rapamicin (100 nmol/L) in the presence of 50 ng/ml RANKL for 5 days.Bone-resorbing activity was evaluated by BD BioCoatTM OsteologicTM Bone Cell Culture System.The expression of osteoclast-specific genes like TRAP,capthesin K,calcitonin receptor (CTR) and matrix metalloproteinase (MMP-9) was evaluated by RT-PCR.The expression of tumor necrosis factor-α(TNF-ct) S6K1Thr389,S6 Ser235/236,4E-BP1Thr37/46 and c-Fos protein was evaluated by ELISA kit and Western blot analysis,respectively.Results Mefformin dose-dependently inhibited RANKL-stimulated osteoclasts differentiation in Raw264.7 cell culture,as manifested by decrease of TRAP-positive multinucleated cells and pit erosion area,down-regulation of TRAP,cathepsin K,CTR and MMP-9 mRNA and reduction of TNF-α and c-Fos protein expression.Further study revealed that RANKL activated mTOR complex 1(mTORC1) signaling,while mefformin impaired RANKL-stimulated mTORC1 signaling.Rapamycin,an mTORCl-specific inhibitor and immunosuppressive macrolides could also prevent RANKL-induced osteoclast differentiation and bone resorption in vitro.Conclusion Mefformin inhibits osteoclastogenesis in vitro,which may due to reduction of TNF-α and c-Fos protein expression,and mTORC1 signaling is involved in this process.

Objective:To evaluate the anterior expansion of sacral foramen and decompression of sacral plexus via the lateral-rectus approach (LRA) in the surgical treatment of sacral fractures complicated with sacral plexus injury.Methods:From January 2013 to June 2018, 11 patients were treated at Department of Orthopaedics, The Third Hospital Affiliated to Southern Medical University for obsolete sacral fractures complicated with sacral plexus injury. They were 8 males and 3 females, aged from 17 to 54 years (average, 38 years). According to the Denis classification, all the sacral fractures belonged to Denis Zone Ⅱ. According to British Medical Research Council (BMRC) grading system, the nerve injury was complete damage in 2 cases and partial damage in 9. The mean time from injury to surgery was 6 months (range, from 0.7 to 12.0 months). After the sacroiliac joint was exposed via the LRA, the lumbosacral trunk was exposed and released between iliac vessels and the iliopsoas. Next, the S1 foramen was expanded and the S1 nerve root was released after separation of the median sacral artery and the internal iliac artery. Reduction and fixation of the sacroiliac joint was carried out for patients with unstable sacral fracture. X-ray and CT examinations of the pelvis were performed to evaluate fracture healing and neurological function recovery postoperatively.Results:Of this cohort of 11 cases, operation succeeded in 10 but failed in one whose sacral fracture was found to have completely healed with the S1 foramina totally occluded. The surgical time averaged 110 min (range, from 70 to 220 min) and the blood loss 1, 100 mL (range, from 450 to 2, 800 mL). Postoperative X-ray and CT examinations showed that the sacral foramens were expanded significantly without any complications. The follow-up time averaged 18 months (range, from 12 months to 4 years). By the BMRC grading system at the last follow-up, the neural function was completely recovered in 5 cases, partially recovered in 4 cases and not recovered in one.Conclusion:Significant anterior expansion of sacral foramen and decompression of sacral plexus via the LRA is a viable and effective alternative for treatment of sacral fractures complicated with sacral plexus injury.

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 evaluate the clinical outcome of bleeding control by preoperative embolization of internal iliac artery with DSA and intra?operative presetting abdominal aorta balloon, combine with the operation techniques of exposure, reduc?tion and internal fixation of pelvic fracture through lateral?rectus approach. Methods From March 2012 to May 2015, 7 patients with type C3 pelvic fractures admitted to our department from March 2012 to May 2015, treated with preoperative embolization of internal iliac artery under digital subtraction angiography 2 h before surgery and presetting abdominal aorta balloon were retrospec?tively reviewed. There were 3 males and 4 females, with an average age of 34 years (range, 16 to 61 years). According to AO classi?fication, all 7 cases belonged to type C3 (3.2:5 cases;C3.3:2 cases), including 5 cases with limb fracture, 2 cases with craniocere?bral trauma, 4 cases with pulmonary contusion, 2 cases with injury of abdominsal organs. Time from injury to operation was 19 days on average (10 to 33 days). Patients received damage control surgery treatment including bleeding control and temporary ex?ternal fixation, and ipsilateral tractions with heavy weight, intensive care and corrections of general situation before operation. The fracture model was manufactured by 3D printing and fracture reduction was simulated on computer preoperatively. Embolization of internal iliac artery was performed in the side of severe displaced sacroiliac joint with DSA 2 hours preoperatively. Reduction was performed to stabilize anterior-posterior pelvic ring and acetabular fractures via the intraoperative lateral?rectus approach. And 2 cases were performed by temporary balloon occlusion of abdominal aorta (≤60 min) for bleeding control in reduction of in the side of sacroiliac joint fractures. Results All the 7 cases had undergone the operations successfully, and the operating time was from 135-320 min with blood loss from 440-3 350 ml. According to Matta radiological evaluation postoperatively, reduction of pelvic fracture was rated as anatomic in 5 cases, satisfactory in 2, without complications. All 7 cases were complicated with lumbosacral plexus injury or lumbosacral trunk injury at different degrees (M0 2 cases, M1 2 cases, M2 2 cases, M3 1 case). According to the BMRC scoring system, 5 cases had well recovered and the other 2 cases had no improvement after three months (M4 2 cases, M5 3 cases). Conclusion Surgical management of pelvic fracture through preoperative internal iliac artery embolization and intra?oper?ative occlusion of abdominal aorta could effective control bleeding and achieve favorable conditions for reduction. Lateral?rectus approach can provide adequate exposure of the anterior and posterior ring, and this approach could also provide excellent visual control of reduction and fixation.

This study showed a case of a patient with central dislocation of the femoral head without involvement of anterior or posterior column of the acetabulum. The patient was associated with endocrine disorders caused by pituitectomy, severe osteoporosis caused by a long-term gulucocorticoids intake history, and poor bone quality of the quadrilateral plate. The direct impact of the femoral head on the quadrilateral plate after trauma resulted in purely central dislocation of the femoral head. 3D printing technique was used to print the fracture model for observation of the fracture morphology and the simulated operation before surgery. The variable-angle locking acetabular plate with a propeller-like shape was designed on the basis of the mirror of the ipsilesional semi-pelvis. This fracture was reduced via the lateral-rectus approach under direct vision. The quadrilateral surface fractures were fixed by the variable-angle locking acetabular plate which was used as a template for reduction. The follow up after surgery showed good reduction and fixation, equal length of double lower limbs, good positive and passive motion of the injured hip joint and without perioperative complications. This report describes an isolated quadrilateral plate fracture that has not yet been classified. It was effectively treated by using a customized variable-angle locking acetabular plate with a propeller-like shape via the lateral rectus approach.

OBJECTIVETo study the clinical effect and surgical operating points of pararectus approach for the internal fixation of acetabular both-column fractures with concurrent displaced quadrilateral plate fractures.

METHODSFrom January 2012 to December 2013, in the Third Affiliated Hospital of Southern Medical University, 15 patients with acetabular both-column fractures and displaced quadrilateral plate fractures were surgically managed through the pararectus approach. There were 11 male and 4 female patients, with an average age of 40 years (from 19 to 61 years). According to Judet-Letournel classification, there were 9 anterior column plus posterior hemitransverse fractures, 6 both-column fractures, 8 cases involving the pelvic fracture. All these fractures were treated through the pararectus approach, in the horizontal position with general anesthesia. The pre-bended plate was placed in interior pelvic ring to fix the anterior wall, anterior column and quadrilateral plate in direct sight. Then, the posterior column was exposed and fixed with antegrade lag screw. Patients were followed up in 4 weeks, 12 weeks, 6 months, 1 year after the operation, and the anteroposterior radiograph of pelvis and the X-ray examination of the fractured hip was performed.

RESULTSAll the 15 cases underwent the operation successfully. Postoperative X-ray and CT exams showed excellent and good reduction of anterior column, posterior column and quadrilateral plate, with none surgical complication occurred. According to the Matta radiological evaluation postoperatively, reduction of acetabular fracture was rated as excellent in 9 cases, good in 3 cases and poor in 3 cases. The rate of excellent and good was 12/15. After 8 to 18 months' follow-up (median follow-up time was 14 months), all the patients gained bone union. According to the modified Merle D'Aubigne and Postel scoring system, 9 cases were excellent, 4 were good, and 2 were fair. The rate of excellent and good was 13/15.

CONCLUSIONSSurgical management of acetabular fractures through the pararectus approach can provide adequate exposure of reducing and fixing both-column acetabular fractures with concurrent displaced quadrilateral plate fractures, which has a good effect in clinical application.

Acetabulum ; pathology ; surgery ; Adult ; Anesthesia, General ; Bone Plates ; Bone Screws ; Female ; Fracture Fixation, Internal ; methods ; Hip Fractures ; pathology ; surgery ; Humans ; Male ; Middle Aged ; Pelvic Bones ; pathology ; surgery ; Postoperative Period ; Spinal Fractures ; Treatment Outcome ; Young Adult

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 investigate reduction and fixation of complex acetabular fractures using three-dimensional (3D) printing technique and personalized acetabular wing-plate via lateral-rectus approach. Methods: From March to July 2016, 8 patients with complex acetabular fractures were surgically managed through 3D printing personalized acetabular wing-plate via lateral-rectus approach at Department of Orthopedics, the Third Affiliated Hospital of Southern Medical University. There were 4 male patients and 4 female patients, with an average age of 57 years (ranging from 31 to 76 years). According to Letournel-Judet classification, there were 2 anterior+ posterior hemitransverse fractures and 6 both-column fractures, without posterior wall fracture or contralateral pelvic fracture. The CT data files of acetabular fracture were imported into the computer and 3D printing technique was used to print the fractures models after reduction by digital orthopedic technique. The acetabular wing-plate was designed and printed with titanium. All fractures were treated via the lateral-rectus approach in a horizontal position after general anesthesia. The anterior column and the quadrilateral surface fractures were fixed by 3D printing personalized acetabular wing-plate, and the posterior column fractures were reduction and fixed by antegrade lag screws under direct vision. Results: All the 8 cases underwent the operation successfully. Postoperative X-ray and CT examination showed excellent or good reduction of anterior and posterior column, without any operation complications. Only 1 case with 75 years old was found screw loosening in the pubic bone with osteoporosis after 1 month′s follow-up, who didn′t accept any treatment because the patient didn′t feel discomfort. According to the Matta radiological evaluation, the reduction of the acetabular fracture was rated as excellent in 3 cases, good in 4 cases and fair in 1 case. All patients were followed up for 3 to 6 months and all patients had achieved bone union. According to the modified Merle D′Aubigné and Postel scoring system, 5 cases were excellent, 2 cases were good, 1 case was fair. Conclusions Surgical management of complex acetabular fracture via lateral-rectus approach combine with 3D printing personalized acetabular wing-plate can effectively improve reduction quality and fixation effect. It will be truly accurate, personalized and minimally invasive.

Objective:To investigate the clinical efficacy of integrated acetabular wing-plate in the management of both column fractures with posterior wall involvement via the lateral-rectus approach.Methods:A retrospective case series analysis was performed on 43 patients with both column fractures involved with posterior wall admitted to Third Affiliated Hospital of Southern Medical University from March 2016 to June 2020. There were 35 males and 8 females, aged 19-78 years [(47.3±13.3)years]. The single lateral-rectus approach was used to expose, reduce and fix the fracture using the integrated acetabular wing-plate. Operation time, incision length, intraoperative blood loss and bone healing time were recorded. Quality of fracture reduction was assessed according to the Matta reduction criteria at postoperative 2 days, and hip function by the modified Merle d′Aubigné-Postel score at postoperative 3 months and 12 months. Postoperative complications were observed.Results:All patients were followed up for 12-48 months [(28.1±13.1)months]. Operation duration was 35-150 minutes [(84.6±26.3)minutes], with incision length of 8-12 cm [(9.4±1.0)cm] and intraoperative blood loss of 100-1 200 ml [(200(300, 500) ml]. Bone healing time was 3-6 months [(3.9±0.9)months]. According to Matta reduction criteria,the results were excellent in 32 patients, good in 7 and poor in 4 at postoperative 2 days, with the excellent and good rate of 91%. The modified Merle d′Aubigné-Postel score was 12-18 points [(16.1±1.5)points] at postoperative 3 months, and 13-18 points [(17.3±1.2)points] at postoperative 12 months ( P<0.01). According to modified Merle d′Aubigné-Postel score, the results were excellent in 3 patients, good in 34 and fair in 6 at postoperative 3 months, with the excellent and good rate of 86%; and the results were excellent in 32 patients, good in 9 and fair in 2 at postoperative 12 months, with the excellent and good rate of 95% ( P<0.01). Postoperative complications were incision fat liquefaction and infection in 1 patient, weakness of hip adduction in 5 and screw loosening with traumatic arthritis in 1. There was no sciatic nerve injury or heterotopic ossification. Conclusion:For both column fractures with posterior wall involvement, single lateral-rectus approach combined with integrated acetabular wing-plate has advantages of short operation time, minor trauma, low rate of bleeding and complications, and good hip function recovery, indicating satisfactory clinical effect.

Objective:To explore the surgical techniques and clinical effects of minimally invasive adjustable plate (MIAP) together with distraction reduction by minimally invasive anterior pelvic ring internal fixator (INFIX) in the treatment of fresh Denis type ⅡB sacral fracture with sacral nerve injury.Methods:From June 2017 to June 2020, 12 fresh Denis type ⅡB sacral fractures were treated by anterior-posterior distraction reduction and fixation with MIAP and INFIX. There were 8 males and 4 females, with an average age of 30 years (from 16 to 44 years). Preoperatively, imaging found Denis ⅡB fracture of the sacrum and magnetic resonance neurography of the lumbosacral plexus showed injury to the sacral nerve root at the sacral foramen. All patients had symptoms of S 1 nerve root injury on the affected side after injury, with 9 cases of grade M0 and 3 cases of grade M1. The time from injury to operation averaged 11 days (from 5 to 19 days). INFIX combined with MIAP was used to distract and fixate the compressed sacral fracture. The quality of fracture reduction and recovery of sacral nerve function were evaluated postoperatively. Results:According to the criteria proposed by Lindahl et al., the quality of fracture reduction was excellent in 8 cases, good in 2 and fair in 2. The 12 cases were followed up for an average of 20 months (from 12 to 36 months). All sacral fractures got united after an average of 6 weeks (from 5 to 8 months). At one-year follow-up, according to the criteria proposed by the Nerve Injuries Committee of the British Medical Research Council, the postoperative muscle strength recovery was evaluated as complete recovery in 10 cases and as partial recovery in 2 cases.Conclusion:In the treatment of fresh Denis type ⅡB sacral fracture, MIAP combined with INFIX can obtain satisfactory clinical effects because the compressed sacrum can be effectively distracted, the sacral foramen be expanded and the sacral nerve be decompressed indirectly.