Computer-Assisted Surgical Navigation for Primary and Metastatic Bone Malignancy of the Pelvis: Current Evidence and Future Directions

Long-term outcomes of computer navigation-assisted resection for primary pelvic sarcomas

Aims

The aim of this study was to evaluate the long-term outcomes of computer navigation-assisted resection for primary pelvic bone tumours.

Methods

Using our prospectively collected oncology database, a retrospective case control study was conducted on 63 patients who underwent computer navigation-assisted resection and 145 patients who underwent non-navigated resection for primary pelvic sarcomas between January 2000 and December 2018. The rates of local recurrence and mortality were calculated using the Kaplan-Meier method. The function and complications were recorded in the follow-up.

Results

The local recurrence rates were 9.5% (6/63) in the navigation group and 19.3% (31/145) in the non-navigation group, respectively (p = 0.040). The two-, five-, and ten-year local recurrence-free survival (LRFS) rates were significantly higher in the navigation compared with non-navigation group (two-year 95% (95% CI 85 to 98) vs 86% (95% CI 79 to 91); p = 0.041; five-year and ten-year 89% (95% CI 77 to 95) vs 75% (95% CI 66 to 82); p = 0.025). Meanwhile, the two-, five-, and ten-year disease-specific survival (DSS) rates were statistically higher in the navigation compared with the non-navigation group (two-year 89% (95% CI 78 to 95) vs 76% (95% CI 68 to 82); p = 0.032; five-year 85% (95% CI 74 to 92) vs 63% (95% CI 54 to 71); p < 0.001; ten-year 85% (95% CI 74 to 92) vs 59% (95% CI 50 to 67); p < 0.001). The multivariate Cox regression showed that the use of navigation was associated with better LRFS and DSS. The mean Musculoskeletal Tumor Society (MSTS) scores were not found to be superior in the navigation group (85% (SD 10) in the navigation group vs 84% (SD 13) in the non-navigation group; p = 0.742).

Conclusion

This study shows that computer navigation-assisted surgery improves the ability to achieve negative bone margins for primary pelvic sarcomas and has better DSS at long-term follow-up. Obtaining adequate soft-tissue margins remains a challenge, and our results show navigation assistance did not result in significant soft-tissue margin improvement. No function improvement was found, and further research is warranted to focus on precise resection and the important preservation of normal structures.

The role of computer-assisted navigation in pelvic tumor surgery: A systematic review and meta-analysis

BACKGROUND

Pelvic bone tumors frequently pose significant challenges due to their proximity to noble structures, including blood vessels, nerves, and organs. Computer-assisted navigation (CAN) for pelvic bone oncology surgery was introduced in the early 2000s to improve accuracy and precision of pelvic tumor resections. The objective of this systematic review and meta-analysis was to evaluate the differences in surgical accuracy, clinical outcomes, recurrence rates, and complications in pelvic bone tumor resections performed with or without CAN.

METHODS

The literature search was independently conducted by two reviewers on September 30, 2024 on PubMed, Scopus, and Cochrane Library databases. Observational studies investigating oncologic outcomes associated with the use of navigation systems in the treatment of primary pelvic bone tumors were included. Meta-analysis was performed using Review Manager software to compare margin status, local recurrence (LR) rates, metastasis rates, and major complications between navigated and non-navigated pelvic tumor surgeries.

RESULTS

Eleven studies comprising 402 patients (mean age 49.3 years) were included. CAN significantly reduced LR rate (p = 0.008) and increased the rate of negative margins (p = 0.0007) compared to non-navigated group. No significant differences were observed in metastasis rate (p = 0.18) or major complications (p = 0.16) between the two groups. The five-year overall survival averaged 78.5 % in navigated surgeries.

CONCLUSION

CAN offers significant benefits in the treatment of pelvic tumors as enhances surgical precision, reduces LR, and increases wide-margin resections compared to non-navigated surgery.

Tripod Fixation of Periacetabular Metastatic Lesions Using the IlluminOss Device

Background

Percutaneous tripod fixation of periacetabular lesions is performed at our institution for patients with metastatic bone disease and a need for quick return to systemic therapy. We have begun to use the IlluminOss Photodynamic Bone Stabilization System instead of the metal implants previously described in the literature because of the success of the IlluminOss implant in fixing fragility fractures about the pelvis.

Description

At our institution, the procedure is performed in the interventional radiology suite in order to allow for the use of 3D radiographic imaging and vector guidance systems. The patient is positioned prone for the transcolumnar PSIS-to-AIIS implant and posterior column/ischial tuberosity implant or supine for the anterior column/superior pubic ramus implant. Following a small incision, a Jamshidi needle with a trocar is utilized to enter the bone at the chosen start point. A hand drill is utilized to advance the Jamshidi needle according to the planned vector; alternatively, a curved or straight awl can be utilized. The 1.2-mm guidewire is placed and reamed. We place both the transcolumnar and posterior column wires at the same time to ensure that there is no interference. The balloon catheter for the IlluminOss is assembled on the back table and inserted according to the implant technique guide. The balloon is inflated and observed on radiographs in order to ensure that the cavity is filled. Monomer is then cured, and the patient is flipped for the subsequent implant. Following placement of the 3 IlluminOss devices, adjunct treatments such as cement acetabuloplasty or cryoablation can be performed.

Alternatives

Alternative treatments include traditional open fixation of impending or nondisplaced acetabular fractures in the operating room, or percutaneous implant placement in the operating room. Implant placement may be performed with the patient in the supine, lateral, or prone position, depending on surgeon preference. Alternative implants include standard metal implants such as plates and screws, or cement augmentation either alone or with percutaneous screws. Finally, ablation alone may be an alternative option, depending on tumor histology.

Rationale

Open treatment of acetabular fractures is a more morbid procedure, given the larger incision, increased blood loss, longer time under anesthesia, and increased length of recovery. Percutaneous fixation may be performed in either the operating room or interventional radiology suite, depending on the specific equipment setup at an individual institution. At our institution, we prefer utilizing the interventional radiology suite as it allows for more precise implant placement through the use of an image-based vector guidance system and 3D fluoroscopy to accurately identify safe corridors. The use of percutaneous fixation allows for faster recovery and earlier return to systemic therapy. Because the IlluminOss implant is radiolucent, it allows for better evaluation of disease progression and can better accommodate nonlinear corridors or fill a lytic lesion to provide stability.

Expected Outcomes

Postoperatively, we expect the patient to be weight-bearing as tolerated with use of an assistive device. We expect the small incisions to fully heal within 2 weeks. Patients should be able to return to systemic therapy as indicated earlier than with an open procedure.

Important Tips

The use of a hand drill with the Jamshidi needle and trocar can help adjust a drilled pathway and allow for close adherence to a planned vector.Vector guidance systems can be useful to fully capture the area at risk for fracture and to provide maximal stability with the expandable implant, but they are not necessary to perform the procedure.Placing both posterior implants at the same time can be helpful to avoid interference. This is accomplished by drilling and placing the guidewire for both implants prior to reaming and placing the balloon implant.

Acronyms and Abbreviations

CT = Computed tomographyPSIS = posterior superior iliac spineAIIS = anterior inferior iliac spine.

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

OBJECTIVE

Currently, minimally invasive internal fixation is recommended for the surgical treatment of unstable pelvic fractures. The premise and difficulty of minimally invasive internal fixation are minimally invasive reduction of fractures. This review aimed to investigate the indications, surgical strategy and techniques, safety, and efficacy of intelligent robot-assisted fracture reduction (RAFR) system of pelvic ring injuries.

METHODS

This retrospective study reviewed a case series from March 2021 to November 2021. A total of 22 patients with unstable pelvic fracture injuries underwent minimally invasive internal fixations. All pelvic ring fractures were reduced with our intelligent RAFR system. The robot system intelligently designs the optimal position and reduction path based on the patient's preoperative 3D CT. During the operation, the three-dimensional visualization of the fracture is realized through image registration, and the Robot completes the automatic reduction of the fracture. The global 3D point cloud error between the preoperative planning results and the actual postoperative reduction results was calculated. The postoperative reduction results of residual displacement were graded by the Matta Criteria.

RESULTS

Minimally invasive closed reduction procedures were completed in all 22 cases with our RAFR system. The average global 3D point cloud reduction error between the preoperative planning results and the actual postoperative reduction results was 3.41mm±1.83mm. The mean residual displacement was 4.61mm±3.29mm. Given the Matta criteria, 16 cases were excellent, five were good, and one was fair, with an excellent and good rate of 95.5%.

CONCLUSION

Our new pelvic fracture reduction robot system can complete intelligent and minimally invasive fracture reduction for most patients with unstable pelvic fractures. The system has intelligent reduction position and path planning and realizes stable pelvis control through a unique holding arm and a robotic arm. The operation process will not cause additional damage to the patient, which fully meets the clinical requirements. Our study demonstrated the safety and effectiveness of our robotic reduction system and its applicability and usability in clinical practice, thus paving the way towards Robot minimally invasive pelvic fracture surgeries.

TiRobot‑assisted versus conventional fluoroscopy-assisted percutaneous sacroiliac screw fixation for pelvic ring injuries: a meta‑analysis

BACKGROUND

The TiRobot is the only robot that has been reported in the literature for posterior pelvic injuries. We aim to compare TiRobot-assisted pelvic screw fixation with the conventional fluoroscopy-assisted percutaneous sacroiliac screw fixation.

METHODS

We conducted a meta-analysis to identify studies involving TiRobot‑assisted versus conventional percutaneous sacroiliac screw fixation for pelvic ring injuries in electronic databases, including Web of Science, Embase, PubMed, Cochrane Controlled Trials Register, Cochrane Library, Highwire, CBM, CNKI, VIP, and WanFang database, up to April 2022. The following keywords were used: "TiRobot," "robot," "robotic," "pelvic fracture," "screw fixation," "percutaneous," and "pelvic ring injury." Pooled effects of this meta-analysis were calculated using STATA SE version 15.0.

RESULTS

Compared with conventional fluoroscopy-assisted percutaneous sacroiliac screw fixation, TiRobot will result in less radiation exposure time of screw implantation (P = 0.000), less frequency of intraoperative fluoroscopy (P = 0.000), fewer guide wire attempts (P = 0.000), less intraoperative blood loss (P = 0.005), better screw accuracy (P = 0.011), better Majeed score (P = 0.031), and higher overall excellent and good rates of Majeed score (P = 0.018). However, there were no significant differences in terms of operative time (P = 0.055), fracture healing time (P = 0.365), and overall excellent and good rate of reduction accuracy (P = 0.426) between the two groups.

CONCLUSION

TiRobot-assisted fixation has less intraoperative fluoroscopy and intraoperative blood loss, superior screw accuracy, and Majeed score compared with conventional percutaneous sacroiliac screw fixation. TiRobot has no significant effect on operative time, fracture healing time, and reduction accuracy. Given the relevant possible biases in our meta-analysis, we required more adequately powered and better-designed RCT studies with long-term follow-up to reach a firmer conclusion.

Design and evaluation of an intelligent reduction robot system for the minimally invasive reduction in pelvic fractures

Introduction

Pelvic 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.

Methods

The 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.

Results

All 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.

Conclusion

The 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.