Rebuilding the pelvis: advances in robotic-assisted management of complex pelvic fractures

BackgroundSacral fractures are typically caused by high-energy trauma. They often disrupt the pelvic ring and pose complex anatomical challenges, as the sacrum is surrounded by critical structures—including blood vessels, nerves, and internal organs. Traditional open reduction and internal fixation (ORIF) can restore anatomical alignment but requires extensive tissue exposure. This exposure leads to greater tissue trauma, prolonged recovery, and higher risks of infection, hemorrhage, or nerve damage. For these reasons, minimally invasive surgery (MIS) is preferred. However, MIS demands high technical precision. Robot-assisted fracture reduction (RAFR) systems enhance precision in minimally invasive procedures, while finite element analysis (FEA) optimizes preoperative planning by simulating biomechanics. However, clinical evidence for combining these techniques in complex, multi-injury cases is limited.Case presentationA 19-year-old female was admitted to the hospital following high-energy trauma (a fall from height), diagnosed with unstable pelvic fracture (AO C1.3 type), longitudinal sacral fracture (Denis II type with vertical displacement), and multiple concurrent injuries (thoracolumbar fractures, rib fracture, pulmonary contusion, splenic and renal contusions, lumbosacral plexus injury). Preoperative management included supracondylar femoral traction and vital sign stabilization. Preoperative FEA based on the patient’s CT data simulated three internal fixation schemes, showing comparable vertical stability; S1 standard + S2 extended sacroiliac screws were selected to preserve lumbar mobility. The RAFR system was used for surgery: 3D preoperative planning, automatic path design, and intraoperative real-time tracking. Fixation was performed with the selected screws (posterior ring) and an anterior external fixator.ConclusionThis case illustrates the value of combining FEA and RAFR in treating complex sacral fractures with multiple traumas. It highlights that FEA provides a scientific basis for personalized fixation strategy selection, while RAFR achieves precise, minimally invasive reduction, offering a feasible pathway for personalized, minimally invasive management.

Intelligent robot-assisted minimally invasive reduction system for reduction of unstable pelvic fractures

Fractures of the pelvis and acetabulum

Objective To evaluate the modified Stoppa approach in treatment of patients with pelvic and acetabular fractures. Methods We analyzed the outcomes of 26 consecutive patients with fractures of the pelvic ring and 9 patients with acetabular fractures who had been treated between March 2008 and December 2009 by open reduction and internal fixation through the modified Stoppa approach. The modified Stoppa approach was made through a low midline incision to fix the pelvis and acetabular fractures. By Tile classification, the 26 pelvic fractures included 2 cases of B1, 4 of B2, 7 of B3, 4 of C1-1, 2 of C1-2, 4 of C1-3, and 3 of C2. By Letournel classification, the 9 acetabular fractures included one case of anterior column, 3 transverse cases, 2 T type cases, one anterior column plus posterior transverse case, and 2 cases of both columns. For pelvic fractures, the modified Stoppa approach was used exclusively in 10 cases, in combination with the iliac fossa approach in 15 cases, and in combination with the posterior approach in one case. For acetabular fractures, the modified Stoppa approach was used exclusively in 3 cases, in combination with the Kocher-Langenbeck approach in 4 cases, and in combination with the Kocher-Langenbeck and iliac fossa approaches in 2 cases of both columns. Results The average operation time was 90 min (65 to 135 min)and the blood loss averaged 320 mL(150 to 1200 mL) in all but one patient with obsolete fracture of both columns. The reductions of the pelvic and acetabular fractures were all excellent and good. Twenty-two patients with pelvic fracture were accessible for an average follow-up of 4 months. Among them, one case of plate breakage and one case of screw loosening were found. Seven patients with acetabular fracture were accessible for an average follow-up of 4 months. One case of mild hip flexion and one case of ectopic ossification were found in them but there was no femoral head necrosis. Satisfactory functional results were achieved in the 29 cases that had been followed up. Conclusion The modified Stoppa approach may be used exclusively or in combination with other approaches to treat pelvic and acetabular fractures effectively, providing advantages of easy manipulation and a low complication rate. Key words: Pelvis; Acetabulum; Fracture; Surgical approach

A retrospective analysis of percutaneous SI joint fixation in unstable pelvic fractures: Our experience in armed forces

IntroductionPelvic fracture is a severe high-energy injury with the highest disability and mortality of all fractures. Traditional open surgery is associated with extensive soft tissue damages and many complications. Minimally invasive surgery potentially mitigates the risks of open surgical procedures and is becoming a new standard for pelvic fracture treatment. The accurate reduction has been recognized as the cornerstone of minimally invasive surgery for pelvic fracture. At present, the closed reduction in pelvic fractures is limited by the current sub-optimal 2D intra-operative imaging (fluoroscopy) and by the high forces of soft tissue involved in the fragment manipulation, which might result in fracture malreduction. To overcome these shortcomings and facilitate pelvic fracture reduction, we developed an intelligent robot-assisted fracture reduction (RAFR) system for pelvic fracture.MethodsThe presented method is divided into three parts. The first part is the preparation of 20 pelvic fracture models. In the second part, we offer an automatic reduction algorithm of our robotic reduction system, including Intraoperative real-time 3D navigation, reduction path planning, control and fixation, and robotic-assisted fracture reduction. In the third part, image registration accuracy and fracture reduction accuracy were calculated and analyzed.ResultsAll 20 pelvic fracture bone models were reduced by the RAFR system; the mean registration error E1 of the 20 models was 1.29 ± 0.57 mm. The mean reduction error E2 of the 20 models was 2.72 ± 0.82 mm. The global error analysis of registration and reduction results showed that higher errors are mainly located at the edge of the pelvis, such as the iliac wing.ConclusionThe accuracy of image registration error and fracture reduction error in our study was excellent, which could reach the requirements of the clinical environment. Our study demonstrated the precision and effectiveness of our RAFR system and its applicability and usability in clinical practice, thus paving the way toward robot minimally invasive pelvic fracture surgeries.

Objective To discuss the safety and the application of the self-designed multifunctional inflatable pelvis and hip-joint fixator (MIPHF) in damage control in pelvic fracture patients. Methods The MIPHF was subjected to pressure test and quality inspection. From September 2016 to June 2017, 61 pelvic-fracture patients were treated with our self-designed MIPHF as pre-hospital first-aid care according to the concept of damage control orthopedics (DCO) (MIPHF group). The control group consisted of 69 pelvic-fracture patients who had not received pre-hospital first-aid care with the self-designed MIPHF from December 2015 to August 2016. There were no statistically significant differences between the two groups in gender, age, types of pelvic fracture, and preoperative injure severity score (ISS). The study compared the two groups for the case fatality rate, volume of blood transfused during surgeries, early complication rates, fracture reduction (Matta standards), and long-term efficacy (Cole scores). Results The pressure test showed that the MIPHF had a good fixation effect on the pelvis. And the quality inspection showed that the material used for the MIPHF was in line with national standards and the safety was guaranteed. The MIPHF group had 1 death (1.6%) and the control group had 8 deaths (11.6%), which was a significant difference (χ2=4.979, P=0.026). All survival patients in both groups were followed up. The MIPHF group (61 cases) received 3.0 to 18.0 months follow-up, with an average of 9.0 months. And the control group (69 cases) had 18.0 to 30.0 months follow-up, with an average of 21.9 months. In the MIPHF group, 23 cases were treated conservatively, and 37 cases were treated with surgery. Among them, 3 cases were fixed with external fixator, 20 cases with anterior open reduction and internal fixation, 9 cases with posterior open reduction and internal fixation, and 5 cases with combined anterior and posterior fixation. The timing of surgery was 1 to 20 days after injury, with an average of 4.1 days. The volume of blood transfused in the MIPHF group during surgery was 200 to 1500 ml, with an average of 628.6 ml. In the control group, 27 patients were treated conservatively, and 42 patients were treated with surgery. Among them, 2 cases were fixed with external fixator, 24 cases with anterior open reduction and internal fixation, 10 cases with posterior open reduction and internal fixation, and 6 cases with combined anterior and posterior fixation. The timing of surgery was 1 to 15 days after injury, with an average of 3.1 days. The volume of blood transfused in the control group during surgery was 200 to 4000 ml, with an average of 1 707.1 ml. There was a significant difference between the two groups in intraoperative blood transfusion(Z=-2.330, P=0.020). The MIPHF group had 10 (16.4%) cases of early serious complications and the control group had 22 (31.9%) cases, which had a significant difference (χ2=4.187, P=0.041). According to the criteria proposed by Matta et al., the good rate of results for treating fractures was 82.0% in the MIPHF group and 60.9% in the control group, which got a significant difference (χ2=6.967, P=0.008). The MIPHF group and the control group also differed significantly in their mean long-term Cole scores (27.2±4.0 versus 25.1±5.6, t=2.457, P=0.015). Conclusion MIPHF, which reflects the DCO concept, may be recommended as pre-hospital first-aid care for patients with pelvic fracture because it can lessen bleeding and prevent secondary pelvic injury, thus reduce case fatality rate and the incidence of complications. It can also improve the success rate of treating pelvic fracture, which will positively affect long-term outcomes. Key words: Pelvis; Fractures, bone; External fixators; First aid

To introduce the experience of intelligent monitoring system assisted pelvic fracture closed reduction to treat complex pelvic fracture in a minimally invasive method. A 30-year-old male patient with complex pelvic fracture caused by a falling injury was treated in December 2019. The pelvic fracture was diagnosed by X-ray film and CT three-dimensional reconstruction. The AO/Orthopaedic Trauma Association (AO/OTA) classification was 61-C3.3 type (H-shaped sacrum fracture with pubic symphysis separation). At 48 hours after injury, the vital signs were stable, and the operation was performed. The pelvic fracture was reduced with the help of pelvic reduction frame and skeletal traction, the intelligent monitoring system, and fixed with the channel screws. The intraoperative blood loss was 50 mL, the operation time was 180 minutes, and the fluoroscopy time was 45 seconds. The incision healed well after operation. The X-ray film of pelvis was taken on the next day after operation, and the fracture reduction was evaluated as anatomical reduction according to Matta standard; CT three-dimensional reconstruction showed that the fixation screws were all located in the cortex of bone, without penetrating the cortex of bone. The intelligent monitoring system assisted pelvic fracture closed reduction is reliable in the minimally invasive treatment of complex pelvic fractures, which can achieve good results and reduce intraoperative fluoroscopy.

Objective: The X-ray and CT features of minimally invasive percutaneous pedicle screw for open reduction and internal fixation and traditional open reduction and internal fixation for thoracolumbar fractures were compared. Methods: Sixty-two patients with thoracolumbar fractures were analyzed with single vertebral body injury without obvious osteoporosis. Patients were randomly divided into two groups. In group A, minimally invasive percutaneous pedicle screws were used for open reduction and fixation. Group B was treated with thoracolumbar vertebral fracture with traditional incision and reduction and internal fixation with posterolateral fusion. Both groups followed standard surgical methods and methods, the same postoperative treatment and functional exercise plan. Results: During a 9-month follow-up, X-ray and computed tomography were used to analyze fracture joint motion injuries. The recovery rate of vertebral height in group A was significantly better than that in group B. At 9 months after operation, the recovery rate of vertebral height in group A increased. The neural function was similar, but the improvement rate in group A was significantly better than that in group B. Conclusions: Minimally invasive percutaneous pedicle screws for open reduction and internal fixation are compared with traditional open reduction and internal fixation for thoracolumbar fractures. Vertebral body height, symptom improvement, and neurological recovery after a lumbar fracture. However, minimally invasive percutaneous pedicle screws for open reduction and internal fixation can immediately increase the compression stability of the anterior spine and reduce complications such as nail and rod rupture due to excessive fixation pressure.

Objective To investigate the method and effect of minimally invasive surgery assisted by 3D printing technique on complex pelvic fractures. Methods From July 2013 to June 2015, a total of 54 cases of complicated pelvic fracture patients were randomly divided into 3D group and control group, 3D group were treated with minimally invasive surgery assisted 3D printing technology, and the control group were given conventional methods of open reduction and internal fixation. The operation time, blood loss and postoperative functional recovery of the two groups were evaluated. Results The 54 patients were followed for posterior fixation, the operation time was (64.2±4.7) min and (98.6±3.7) min in 3D group and control group. The amount of bleeding was (82.4±8.1) ml and (142.6±9.3) ml. The incidences of postoperative incision infection or necrosis and other complications were 3.7% and 11.1%, the differences were significant (P 0.05). Conclusions 3D printing technology assisted minimally invasive surgical treatment of complicated pelvic fracture surgery design to form a three-dimensional concept directly before operation, to avoid injury death crown arteries and iliac vessels, reliable fixation, can greatly shorten the operation time, has little surgical trauma, little bleeding, less complications, is simple to remove the internal fixation by secondary operation, fully embodies the concept of minimal invasion. Key words: Pelvic fractures; Minimally invasive; 3D printing technology

Comprehensive emergency management and early stabilization are pivotal in treating complex pelvic and acetabular fractures. Surgical treatment of displaced Pelvi-acetabular fractures has evolved from conservative to operative treatment. In the current study, we presented a series of thirty cases involving complex pelvic fractures as well as acetabular injuries, emphasizing the significance of comprehensive emergency management and appropriate intervention. As a result of the present case series, we highlight, the crucial role of a comprehensive operative plan that differentiates among patients based on their general condition, the available resources and the surgeon's preference. Central to our approach was the utilization of the Stoppa and Kocher-Langenbach techniques for internal fixation, demonstrating their efficacy in addressing these challenging fractures. The findings of the current series, reveal that, the functional outcome correlated well with the quality of reduction. Also, we recommended that the Stoppa and Kocher-Langenbach techniques be used as an effective treatment approach to address these complex fracture’s.

<p><strong>Background:</strong> Complex pelvic fractures have high mortality and morbidity hence required urgent resuscitation, haemodynamic stabilization and fracture fixation. Keeping in mind the various schools of thought regarding definitive management, there is need to study the outcomes of complex pelvic fractures after internal fixation surgery.</p><p><strong>Methods:</strong> Twenty patients with complex pelvic fractures treated with internal fixation surgery in between 1<sup>st</sup> June 2018-31<sup>st</sup> December 2019 with at least 12 months follow-up were included. Clinical and functional outcome of these patients was studied and evaluated using Majeed and Hannover scoring systems.</p><p><strong>Results:</strong> Of 20 patients, 19 had closed while 1 had open pelvic fracture while 11 had tile type B and 9 had tile type C fracture. After 12 months of follow up, 72% patients of tile B fractures and 55.6% in tile C had excellent Majeed score with rest having good score. Hannover score was very good in 36.4% tile B cases and 22.2% tile C cases and good in 63.6% tile B cases and 77.8% tile C cases. Type of fracture (type B or type C) had a statistically significant co-relation with chronic pain (p=0.016). It was also found that urogenital injury and sexual dysfunction (p=0.007) had a significant co-relation.</p><p><strong>Conclusions:</strong> Early definitive internal fixation in patients with complex pelvic fracture had very good clinical and functional outcome. Most common associated injuries in complex pelvic fractures are urogenital injuries due to close proximity. In the outcomes chronic pain and sexual dysfunction are major issues. The sexual dysfunction patients usually associated fracture of pubic rami or pubic diastasis.</p>

Computer-aided automatic planning and biomechanical analysis of a novel arc screw for pelvic fracture internal fixation

Percutaneous Fixation in Pelvic and Acetabular Fractures: Understanding Evolving Indications and Contraindications

Combined ipsilateral acetabular and femoral neck fractures are the result of high-energy trauma. Satisfactory treatment for this injury pattern remains a challenge, since traditional open reduction and internal fixation (ORIF) is always accompanied by a high prevalence of posttraumatic arthritis and avascular necrosis of the femoral head. Eight of 502 acetabular fractures from 1990 to 2008 were diagnosed with combined ipsilateral femoral neck fracture, in which 5 patients' fractures were associated with hip dislocation. These patients were injured from falls, traffic accidents, or crushing accidents. Radiographs and computed tomography scans were taken to check acetabular and femoral neck fractures. All of the patients underwent surgery using appropriate approaches and techniques. Postoperative radiographs demonstrated anatomic or satisfactory reduction for acetabular fractures as well as excellent or good reduction for femoral neck fractures in all of the patients. Follow-up radiographs showed femoral head necrosis in the 5 patients with femoral head dislocations, but not in the other 3 patients. We have seen few patients with this injury pattern, which makes us unable to detect significant differences between the patients associated with femoral head dislocation and those without femoral head dislocation. But by considering the results of our study and those reported in the literature, we believe that for patients with ipsilateral acetabular and femoral neck fractures without hip dislocation, satisfactory results could be expected after ORIF. But for those cases associated with hip dislocation, alternative methods such as acute THR as primary treatment are worthy of consideration.