Computational analysis on the feasibility of transverse iliosacral screw fixation for different sacral segments

The efficacy of "TiRobot"orthopaedic robot-assisted VS conventional fluoroscopic percutaneous screw fixation of the sacroiliac joint

PURPOSE

This study is to compare the precision and safety of the orthopaedic robot with conventional fluoroscopy for assisted percutaneous sacroiliac joint screw implantation.

METHODS

Retrospective analysis was performed on the clinical data of 57 patients with unstable posterior pelvic ring injuries who were admitted and met the criteria between January 2017 and January 2022. All of these patients underwent percutaneous sacroiliac joint screw implantation, and their clinical data were split into two groups based on the surgical technique: a RA group (robot-assisted implantation, 30 patients, 54 screws) and a CF group (conventional fluoroscopic freehand implantation, 27 patients, 42 screws). There were 96 screws placed in total. The durations of the two groups' operations, fluoroscopy examinations, fluoroscopy doses, total number of fluoroscopies, and intra-operative guide pin applications were noted and compared. On post-operative CT scans, the placement of each screw was assessed using the Gertzbein-Robbins classification. Finally, imaging Matta criteria were used to assess the sacroiliac joint fracture reduction. The Majeed functional score was used to assess clinical function.

RESULTS

Both groups successfully completed 57 procedures in total. In both groups, there were no consequences from vascular injury, wound infection, or urinary tract infection. Additionally, there were no complications from robotic-induced nerve injury, operating time, fluoroscopic dose, and the frequency of fluoroscopic; the number of percutaneous punctures in the RA group was lower than that of the CF group.There were statistically significant differences between the aforementioned data (P < 0.05). The modified Matta evaluated the effectiveness of fracture reduction. In the RA group, there was no statistically significant difference between the CF group (P > 0.05). According to the modified Gertzbein-Robbins classification criteria, the 54 screws implanted in the RA group were classified as follows: class A (45), class B (5), class C (4), and class D (0); the accuracy rate of the implants was 92.59%. Forty-two screws implanted in the CF group, 30 screws were defined class A, class B (3), class C (7), and class D (2). The accuracy rate of the implants was 78.57%(χ2 = 3.967, P < 0.05). There was a statistically significant difference between the two groups. The Majeed score 30 patients in RA group, one month post-operation, 16 considered exceptional, eight decent, six moderate, and zero bad. Post-operation more than six months,25 recorded exceptional, five decent. By the time,27 patients in CF group,12 exceptional grade, eight decent, six moderate, and one bad,one month post-operation. Post-operation more than six months,22 recorded exceptional, five decent.Both group (P > 0.05).

CONCLUSION

"TiRobot" robot-assisted screw implant treatment for unstable posterior pelvic ring injury has a greater success rate than traditional surgery as compared to conventional percutaneous screw implant. It is a precise, secure, and minimally invasive surgical technique that can also be applied to severe pelvic injuries even congenital sacral deformities.

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.

Percutaneous Robot-Assisted versus Freehand S2 Iliosacral Screw Fixation in Unstable Posterior Pelvic Ring Fracture

OBJECTIVES

To assess the efficiency, safety, and accuracy of S₂ (IS) screw fixation using a robot-assisted method compared with a freehand method.

METHODS

This is a retrospective clinical study. We analyzed the patients treated with S₂ IS screw fixation for unstable pelvic fractures from January 2016 to January 2019 in our institution. Sixty-three patients (17 men and 46 women) aged between 21 and 55 years (with an average age of 39.22 ± 9.28) were included in this study. According to the Tile classification, there were 26 (41.3%) type B fractures and 37 (58.7%) type C fractures. All patients were divided into robot-assisted (RA) group (38 patients) or the traditional freehand (FH) group (25 patients). In RA group, the S₂ IS screws were implanted with a robot-assisted technique. And S₂ IS screws were implanted with a traditional freehand technique in FH group. The screw-related complications were recorded during and after the surgery. The position of all screws and fracture reduction was assessed by postoperative CT scans according to the Gras classification. The number of guide wire attempts and the radiation exposure for S₂ screw implantation during operation were also recorded. Finally, the Matta standard was used to evaluate the fracture reduction of the IS joint.

RESULTS

A total of 89 IS screws were implanted into S2 iliosacral joint. Fifty-four screws were placed by RA (38 patients) and 35 screws were by FH (25 patients). There was no difference between the two groups with respect to demographic data. There was no screw-related complications or revision surgery in any group. In terms of screw placement, the excellent and good rate was 100% in the RA group, better than that in the FH group where it was only 85.7% (P < 0.001). The fluoroscopy time was 8.06 ± 3.54 s in RA group, which was much less than that in the FH group (27.37 ± 8.82 s, P < 0.001). The guide wire attempts in the RA group (0.685 ± 0.820) were much less than those in the FH group (5.77 ± 3.34) (P < 0.001). Both the fluoroscopy time per screw and the number of guide wire attempts in the RA group were much less than those in the FH group (P < 0.001). The overall postoperative excellent and good rate of Matta standard in RA and FH groups were 86.8% (34/4) and 90.0% (23/25), respectively (P = 0.750), and there was no statistical difference.

CONCLUSION

The robot-assisted surgery is an accurate and minimally invasive technique. S₂ IS screw implantation assisted by TiRobot to treat the posterior pelvic ring fractures, have a high success rate than the freehand technique. Percutaneous RA S₂ IS screw fixation for unstable posterior pelvic ring injuries is safe and clinically feasible and has great clinical application value.

Role of the Lumbosacral Transition Vertebra and Vertebral Lamina in the Pathogenesis of Lumbar Disc Herniation

OBJECTIVE

To investigate the prevalence of lumbosacral transition vertebrae (LSTVs) in both the normal population and the lumbar disc herniation (LDH) population and to determine the risk factors for LDH.

METHODS

Between January 2019 and September 2020, all patients aged 18-39 years and underwent an anteroposterior (AP) X-ray of the lumbar vertebrae were retrospective reviewed in our institution. Those patients who were diagnosed with LDH were eligible for inclusion in the LDH group. During the same period, those patients admitted to our hospital who underwent an anteroposterior X-ray of the lumbar spine and had not been diagnosed with LDH were included in the control group. Those patients with disease that might affect the lumbar anatomy were excluded from both groups. The type of LSTV was classified according to the Castellvi classification. The height of the lumbar vertebral lamina was evaluated through the h/H index. The inter- and intra-observer reliability was evaluated by one senior radiologist and one senior orthopedist using intraclass correlation coefficient (ICC). The association between the LSTV and the herniation level was also investigated. Binary logistic regression was used to explore the association of different factors between the LDH group and the control group.

RESULTS

Two hundred LDH patients (115 male and 85 female) and 200 individuals (108 male and 92 female) were investigated retrospectively. The prevalence of LSTVs was 71.5% (n = 143) in the LDH group and 34.0% (n = 68) in the control group. The most frequent LSTV types were type Ib and type IIa. The inter- and intra-observer ICCs of the measurement of "h/H" index and the classification of LSTV were all "excellent" (ICC > 0.90). The median h/H index in the control group was significantly higher than that in the LDH group (0.28 (0.26, 0.31) vs 0.34 (0.31, 0.37), P = 0.000). The distribution of the Castellvi classification in the L4/5 and L5/S1 herniation patients was significantly different (P = 0.048). LSTVs, BMI and the h/H index were closely associated with LDH, with odds ratios of 3.06 (95% CI: 2.12-4.43), 1.23 (95% CI: 1.13-1.33) and 0.09 (95% CI: 0.05-0.15), respectively. The incidence of L4/5 disc herniation in patients with an LSTV was significantly more common than that in patients with L5/S1 disc herniation (P = 0.048).

CONCLUSION

The prevalence of LSTVs was 34.0% in the control group and 71.5% in the LDH group; LSTVs and BMI were positively correlated with LDH, and h/H was negatively correlated with LDH.

Dynamic Change of Lumbar Structure and Associated Factors: A Retrospective Study

Objective

To determine whether lumbar anatomy parameters are in dynamic change and related factors.

Methods

This is a retrospective study. Participants who did lumbar computed tomography (CT) scanning in Shandong University Qilu Hospital from October 2017 to March 2019 were selected. The 476 participants were randomly selected as male or female, with the age ranging from 17 to 87 years (mean, 55.19; standard deviation, 14.28 years). All the measurements were taken based on the CT scanning image and the measurement of lumbar morphology was conducted using picture archiving and communication systems (PACS). The angle between the horizontal alignment and pedicle center on median sagittal view, the angle between upper endplate and lower endplate on median sagittal view as well as transverse section angle (TSA) using Magerl point in the axial view was determined by reconstructive CT analysis.

Results

In the overall participants, the angle between the horizontal alignment and pedicle center on median sagittal view of lumbar one to three was significantly decreased with aging, from 3.90° ± 2.81° to −4.18° ± 6.86° (P = 0.002), 5.60° ± 2.89° to −4.14° ± 5.90° (P = 0.030), and 4.75° ± 2.95° to −2.87° ± 4.68° (P < 0.001), respectively. Additionally, the angle between the horizontal alignment and pedicle center on median sagittal view in male participants of lumbar two was dramatically decreased, from 4.83° ± 2.79° to −4.45° ± 5.97° (P = 0.30). And that of lumbar three in female participants was significantly decreased, from 4.56° ± 2.52° to −2.88° ± 5.03° (P = 0.029). Furthermore, of the overall participants, the angle between upper endplate and lower endplate on median sagittal view of lumbar one to four was associated with aging (P < 0.001, P < 0.001, P = 0.015, P < 0.001, respectively). The angle of lumbar one, two and four in male participants and lumbar one to four in female participants were all significantly related to aging (all P < 0.05). Moreover, in the participants overall, the TSA of lumbar one to three was significantly associated with aging (P = 0.015, P = 0.006 and P = 0.007, respectively). In addition, this angle in lumbar one to lumbar four in male participants were all negatively associated with aging (P = 0.017, P = 0.001, P = 0.005 and P = 0.036, respectively).

Conclusion

Lumbar anatomy parameters are in dynamic change in an age and gender dependent manner. During spine surgery in elderly patients, more attention should be paid to these anatomic changes.