Minimally invasive surgery under fluoro-navigation for anterior pelvic ring fractures

A systematic review and meta-analysis comparing robotic-assisted percutaneous screw fixation and conventional surgical techniques for acetabular fractures

The objective of this comprehensive review and meta-analysis was to evaluate the effectiveness of robot-aided percutaneous screw fixation versus traditional surgical techniques in managing acetabular fractures. We plan to carry out an exhaustive exploration of certain databases (PubMed, CNKI, Embase, and Cochrane Library) to find studies that have been published since the beginning of these databases until August 2024, focusing on patients with acetabular fractures. These studies will compare the efficacy of robot-assisted percutaneous screw fixation with conventional surgical methods. Both English and Chinese literature will be included. We will adhere strictly to the predefined inclusion and exclusion criteria, with a focus on randomized controlled trials and cohort studies. Review Manager 5.4.1 will be utilized for the execution of data analysis. The ROBINS-I instrument will be used to evaluate the bias risk in Not-RCTs. The final analysis included 6 retrospective cohort studies, encompassing a total of 168 patients, with 83 undergoing robot-assisted percutaneous screw fixation and 85 receiving conventional surgery. The results indicated that patients treated with robot-assisted percutaneous screw fixation had shorter OT, fewer intraoperative fluoroscopy instances, and fewer adjustments of guide pins compared to those receiving conventional surgery. However, no significant differences were observed between the two treatment methods in terms of Modified Postel Merle D'Aubigne scores and EBL. The use of robots in percutaneous screw fixation has been demonstrated to be a secure and efficient method for managing acetabular fractures. Compared to conventional ORIF or free-hand screw fixation, this robotic-assisted technique offers significant advantages, including reduced operation time, lower IFF, and fewer guide wire adjustments.

TiRobot-Assisted Percutaneous Cannulated Screw Fixation for Elderly Patients with Fragility Fractures of the Pelvis: A Retrospective Study

OBJECTIVE

The incidence of fragility fractures of the pelvis (FFPs) is increasing in the elderly population, and FFPs that require fixation are a challenge for orthopedic surgeons. The insertion of implants is not risk free due to the complex anatomical and osteoporotic bones and requires a steep learning curve. This study aimed to investigate the clinical efficacy of TiRobot-assisted percutaneous cannulated screw fixation in the treatment of elderly FFP patients.

METHOD

The clinical data of 46 elderly FFP patients who had been treated with percutaneous cannulated screw fixation from May 2020 to September 2022 were retrospectively analyzed. Twenty-four patients were treated with percutaneous cannulated screw fixation assisted by the TiRobot (TiRobot-assisted group) and 22 patients were treated with conventional freehand surgery (freehand group). Postoperative outcomes, including Matta value, excellent and good rate (EGR) of fracture reduction, and accuracy of screw placement (ASP), were compared. Changes in the Visual analog scale (VAS) pain score and the Majeed score were recorded and compared between groups before and after surgery and during the 24-week follow-up. Repeated-measures analysis of variance (ANOVA) and effect sizes were used as analysis methods.

RESULTS

A total of 90 screws were implanted, 51 screws in the TiRobot-assisted group and 39 screws in the freehand group. The operation time of the two groups was 34.1 ± 2.67 min versus 64.5 ± 4.19 min (p < 0.001). There were no screw-related complications or revision surgeries in any group. The Matta value of the TiRobot-assisted group was 5.13 ± 3.52, which was significantly lower than that of the freehand group (9.00 ± 3.68, p < 0.001), while the EGR was 91.67% versus 72.73%, with statistical significance (p < 0.001). The ASP was 100% in the TiRobot-assisted group, better than that in the freehand group, where it was 85.7% (p = 0.043). At each timepoint in the early postoperative period, the VAS score of the TiRobot-assisted group was significantly lower than that of the freehand group and was close to consistent by the last follow-up; the Majeed score of the former was significantly higher than that of the latter at each timepoint of follow-up, with statistical significance (p < 0.001).

CONCLUSION

TiRobot-assisted percutaneous cannulated screw fixation of elderly FFP patients is advantageous over conventional freehand surgery, with less invasion, more accurate screw placement, better fracture reduction, early pain relief, and rapid recovery, suggesting that Freehand method to stabilize FFP in the elderly population.

Laparoscopic Acetabular Surgery (LASY) - vision or illusion?

Displaced acetabular fractures usually require open surgical approaches. Aim of this cadaver study was to evaluate a laparoscopic approach to prepare the anterior acetabular column and the quadrilateral plate in analogy to the laparoscopic pelvic lymphadenectomy. The laparoscopic preparation and anatomy is presented and illustrated step by step in a human cadaver followed by a modular plate osteosynthesis of the anterior column involving the quadrilateral plate is performed via a minimally invasive approach using standard laparoscopic instruments. In conclusion we could demonstrate that the laparoscopic preperitoneal preparation of the acetabulum according to the laparoscopic pelvic lymphadenectomy provides more free range for the surgical instruments compared to a previously described total extraperitoneal approach. The development of specific reduction tools and implants is under investigation. Until then, at least the laparoscopic preparation could be introduced in the clinical setting in the near future. TYPE OF STUDY: Technical note - Cadaver study.

Development of a fluoroscopically guided robotic assistant for instrument placement in pelvic trauma surgery

Purpose: A method for fluoroscopic guidance of a robotic assistant is presented for instrument placement in pelvic trauma surgery. The solution uses fluoroscopic images acquired in standard clinical workflow and helps avoid repeat fluoroscopy commonly performed during implant guidance. Approach: Images acquired from a mobile C-arm are used to perform 3D-2D registration of both the patient (via patient CT) and the robot (via CAD model of a surgical instrument attached to its end effector, e.g; a drill guide), guiding the robot to target trajectories defined in the patient CT. The proposed approach avoids C-arm gantry motion, instead manipulating the robot to acquire disparate views of the instrument. Phantom and cadaver studies were performed to determine operating parameters and assess the accuracy of the proposed approach in aligning a standard drill guide instrument. Results: The proposed approach achieved average drill guide tip placement accuracy of 1.57 ± 0.47    mm and angular alignment of 0.35 ± 0.32    deg in phantom studies. The errors remained within 2 mm and 1 deg in cadaver experiments, comparable to the margins of errors provided by surgical trackers (but operating without the need for external tracking). Conclusions: By operating at a fixed fluoroscopic perspective and eliminating the need for encoded C-arm gantry movement, the proposed approach simplifies and expedites the registration of image-guided robotic assistants and can be used with simple, non-calibrated, non-encoded, and non-isocentric C-arm systems to accurately guide a robotic device in a manner that is compatible with the surgical workflow.

Factors Associated With Failure of Superior Pubic Ramus Screws

OBJECTIVE

Examine factors associated with fixation failure in patients treated with superior intramedullary ramus screws.

DESIGN

Retrospective.

SETTING

Single, Level 1 trauma center.

PATIENTS

Unstable pelvic ring fractures amenable fixation that included superior intramedullary ramus screws.

INTERVENTION

Percutaneously inserted intramedullary superior ramus screw fixation of superior pubic ramus (SPR) fractures.

MAIN OUTCOME MEASUREMENTS

Loss of reduction (LOR) of the SPR fracture defined as >2 mm displacement on pelvic radiographs at any time point in follow-up.

RESULTS

Two hundred eighty-five fractures in 211 patients (age 44, 95% confidence interval 40.8%-46.4%, 59.3% women, 55.1% retrograde screws) were included in the analysis. 14 (4.9%) of fractures had LOR. Patients were significantly more likely to have LOR as age increased (P = 0.01), body mass index (BMI) increased (P = 0.01), and if they were women (P < 0.01). There was a significantly decreased LOR (P < 0.01) as fractures moved further from the pubis symphysis. Retrograde screws were significantly (P < 0.01) more likely to have LOR. In SPR fractures treated with retrograde screws, failure was significantly associated with increasing BMI (P = 0.02), the presence of an inferior ramus fracture (P = 0.02), and trended toward significance with increasing age (P = 0.06), and decreased distance from the symphysis (P = 0.07).

CONCLUSIONS

Superior ramus screws are associated with a low failure rate (4.9%), which is lower than previously reported. Retrograde screw insertion, distance from the symphysis, increasing age, increasing BMI, decreased distance from the symphysis, and ipsilateral inferior ramus fractures were predictors of failure. In these patients, alternative modalities should be considered, although low rates of failure can still be expected.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

A novel Patient-Specific Three-Dimensional Printing Template Based on External Fixation for Pelvic Screw Insertion

PURPOSE

To investigate the clinical effect of novel patient-specific 3D printing templates based on external fixation for pelvic screw insertion compared with the fluoro-navigation technique.

MATERIALS AND METHODS

We retrospectively studied 18 pelvic fracture patients from July 2017 to July 2018. For analysis, patients were divided into two groups: the template group (15 screws in 8 patients) and the fluoro-navigation group (22 screws in 10 patients). The screw insertion time, radiation exposure time, and accuracy of the screw insertion as evaluated by postoperative CT scans were analyzed.

RESULTS

In the template group, the average screw insertion time (11.5 ± 2.3 min/screw) was significantly 50.6% less than that in the fluoro-navigation group (23.3 ± 3.1 min/screw; P < 0.05). The average time of X-ray exposure in the template group (11.5 ± 3.9 s/screw) was also significantly 39.8% less than in the fluoro-navigation group (19.1 ± 2.5 s/screw; P < 0.05). In the template group, the mean deviation distance and angle between the actual and planned screw position was 2.6 ± 0.2 mm and 2 ± 0.3°.

CONCLUSIONS

The patient-specific template based on external fixation can guide the insertion of the pelvic screw accurately and safely while significantly reducing operation and radiation exposure time.

Computer navigation-assisted minimally invasive percutaneous screw placement for pelvic fractures

Pelvic fractures are often caused by high-energy injuries and accompanied by hemodynamic instability. Traditional open surgery has a large amount of bleeding, which is not suitable for patients with acute pelvic fracture. Navigation-guided, percutaneous puncture-screw implantation has gradually become a preferred procedure due to its advantages, which include less trauma, faster recovery times, and less bleeding. However, due to the complexity of pelvic anatomy, doctors often encounter some problems when using navigation to treat pelvic fractures. This article reviews the indications, contraindications, surgical procedures, and related complications of this procedure for the treatment of sacral fractures, sacroiliac joint injuries, pelvic ring injuries, and acetabular fractures. We also analyze the causes of inaccurate screw placement. Percutaneous screw placement under navigational guidance has the advantages of high accuracy, low incidence of complications and small soft-tissue damage, minimal blood loss, short hospital stays, and quick recovery. There is no difference in the incidence of complications between surgeries performed by new doctors and experienced ones. However, computer navigation technology requires extensive training, and attention should be given to avoid complications such as screw misplacement, intestinal injury, and serious blood vessel and nerve injuries caused by navigational drift.

Robot-assisted Minimally-invasive Internal Fixation of Pelvic Ring Injuries: A Single-center Experience

Objective

To investigate the indications, surgical strategy and techniques, safety, and efficacy of robot‐assisted minimally‐invasive internal fixation of pelvic ring injuries.

Methods

The clinical data of 86 patients with anterior and posterior pelvic ring injuries who underwent robot‐assisted minimally‐invasive internal fixation were retrospectively analyzed. The patients included 57 men and 29 women aged between 22 and 75 years, with an average age of (40.2 ± 13.6) years. According to the Tile classification, there were 5 (5.8%) type A2, 48 (55.8%) type B, and 33 (38.4%) type C fractures. The surgical plans were formulated based on the injury type of the pelvic ring, the effectiveness of the reduction, and the integrity of the osseous channel. Posterior pelvic ring injuries were treated with robot‐assisted percutaneous cannulated screw fixation of the sacroiliac joint. Anterior pelvic ring injuries were treated with robot‐assisted percutaneous cannulated screw fixation of the pubic ramus, INFIX fixation, or a “hybrid” fixation. The surgical complications and the efficacy of the surgical treatments were analyzed.

Results

A total of 274 screws were inserted with robotic assistance, of which 262 screws were successfully inserted to a satisfactory position on the first attempt. The number of screws placed per person was 3.2 on average, and the average operation time was 175 min (35–280 min). Fluoroscopies were performed an average of 29.1 times (range, 9–63 times), and it took 6.1 s to place each screw. There were 13 unsatisfactory guiding needle placements during the surgeries, among 7 of which cutting or penetration of the cortex was re‐planned until satisfactory insertions; 1 penetrated the pubic cortex, causing hemorrhage of the “crown of death,” and was changed to “hybrid surgery”. The robot‐assisted surgical wounds all healed by primary intention with satisfactory position and precision of screw insertions. All patients were followed up for 3–6 months, with an average of 4.2 months. There were two postoperative fixation failures, in which both patients had separated symphysis pubes after hybrid surgery. The average Majeed score at the last follow‐up was 92.4 points.

Conclusions

Robot‐assisted surgery is accurate and minimally invasive, with a high success rate for one‐time screw placement and satisfactory clinical results. The indications and surgical strategy should be rigorously selected, the level of surgical techniques mastered, and the operating procedures standardized, all of which may help to prevent surgical complications. Robot‐assisted surgery provides a novel modality for the minimally‐invasive treatment of pelvic ring injuries.

Biomechanical study of three kinds of internal fixation for the treatment of sacroiliac joint disruption using biomechanical test and finite element analysis

BACKGROUND

To compare the stability of sacroiliac joint disruption fixed with three kinds of internal fixation using both biomechanical test and finite element analysis.

METHODS

Five embalmed specimens of an adult were used. The symphysis pubis rupture and left sacroiliac joint disruption were created. The symphysis pubis was stabilized with a five-hole plate. The sacroiliac joint disruption was fixed with three kinds of internal fixation in a randomized design. Displacements of the whole specimen and shifts in the gap were recorded. Three-dimensional finite element models of the pelvis, the pelvis with symphysis pubis rupture and left sacroiliac joint disruption, and three kinds of internal fixation techniques were created and analyzed.

RESULTS

Under the vertical load, the displacements and shifts in the gap of the pelvis fixed with minimally invasive adjustable plate (MIAP) combined with one iliosacral (IS) screw were the smallest, and the average displacements of the pelvis fixed with an anterior plate were the largest one. The differences among them were significant. In finite element analysis and MIAP combined with one IS screw fixation showed relatively best fixation stability and lowest risks of implant failure than two IS screws fixation and anterior plate fixation.

CONCLUSION

The stability of sacroiliac joint disruption fixed with MIAP combined with one IS screw is better than that fixed with two IS screws and anterior plate under vertical load.

Robot-assisted percutaneous screw placement combined with pelvic internal fixator for minimally invasive treatment of unstable pelvic ring fractures

Purpose

The purpose of this study was to investigate the safety and efficacy of the combination of robot‐assisted percutaneous screw placement and pelvic internal fixator (INFIX) for minimally invasive treatment of unstable anterior and posterior pelvic ring injuries.

Methods

From September 2016 to June 2017, twenty‐four patients with unstable anterior and posterior pelvic ring injuries were treated with TiRobot‐assisted percutaneous sacroiliac cannulated screw fixation on the posterior pelvic ring combined with robot‐assisted pedicle screw placement in the anterior inferior iliac spine along with INFIX on the anterior pelvic ring. The results of the treatment, including surgery duration, fluoroscopy frequency, total drilling, amount of blood loss, fracture healing time, and postoperative functional outcomes were recorded and compared with another 21 similar patients who underwent conventional manual positioning surgery.

Results

The TiRobot group incurred significantly shorter duration of surgery; less fluoroscopy frequency, intraoperative bleeding, and total drilling than in the conventional group (P < 0.05). Postoperative radiological follow‐up showed that all screws were in the safe area and no screw penetrated the cortex. All wounds healed by primary intention and no iatrogenic damage to the blood vessels, nerves, and organs occurred. Patients showed good tolerance to INFIX and reported no discomfort. The mean follow‐up duration was 5.4 months; the fractures were all healed, no loss of reduction occurred, and the mean Majeed score at the last follow‐up did not show any difference.

Conclusion

TiRobot‐assisted percutaneous screw placement combined with INFIX for the anterior and posterior pelvic ring injuries is accurate, safe, less invasive, and shows satisfactory efficacy, suggesting it is a better method for minimally invasive treatment of unstable pelvic ring fractures.

Comparisons of front plate, percutaneous sacroiliac screws, and sacroiliac anterior papilionaceous plate in fixation of unstable pelvic fractures

BACKGROUND

This observational study was aimed at comparing the clinical efficacy of sacroiliac anterior plate fixation (SAPF), sacroiliac anterior papilionaceous plate (SAPP), and percutaneous sacroiliac screw internal fixation (PSCIF) introduced for patients with unstable pelvic fracture.

METHODS

Seventy-eight patients with unstable pelvic fracture (Tile type B or C) were recruited. Twenty-six patients underwent SAPF, 26 underwent SAPP, and 26 underwent PSCIF. Matta scores were calculated to evaluate the reduction of pelvic fractures, and Majeed scores were applied for the assessment of functional recoveries after surgery. Other perioperative clinical indicators were also recorded, including operation time, bleeding status, length of incision, ambulation time, fracture healing time, and incision infection.

RESULTS

Total operation time of PSCIF was remarkably shorter than that of SAPF and SAPP (P < .05), and the bleeding volume of SAPF and SAPP group was almost 26∼29 times as high as that of PSCIF group (P < .05). Besides, SAPP resulted in significant blood loss compared with SAPF (P < .05), while SAPF resulted in significantly larger operative incision length than SAPP and PSCIF (P < .05). Moreover, patients' stay time was prolonged in both SAPF and SAPP groups than in the PSCIF group (P < .05). Patients who received PSCIF exhibited significantly higher Matta and Majeed scores than those who received SAPF (all P < .05). Finally, SAPP was associated with fewer complications than SAPF, and complications were barely observed in the PSCIF group.

CONCLUSION

PSCIF may be more appropriate for patients with unstable pelvic fractures in comparison with SAPP and SAPF. Besides, SAPP is likely to be more efficacious than SAPF especially for Tile C patients.