Robotic guidance for percutaneous placement of triangular osteosynthesis in vertically unstable sacrum fractures: a single-center retrospective study.

BACKGROUND: To evaluate the effectiveness and safety of robot-aided percutaneous triangular osteosynthesis combined with close reduction for vertically unstable sacrum fractures (VUSFs). METHODS: The data on 21 patients of the VUSF were retrospectively analyzed from November 2016 to January 2021. According to Denis classification, there were 3 cases in zone I, 11 cases in zone II, and 7 case in zone III. The main perioperative indicators were recorded. The maximal angulation and displacement deviations of the screws were analyzed by comparing the planned trajectory with the actual position. Postoperative X-ray radiographs and CT scans were obtained for evaluating the reduction quality. Functional outcome was scored with Majeed criterion. RESULTS: Fourteen patients of the unilateral VUSF and 7 patients of the bilateral VUSF underwent unilateral and bilateral triangular osteosynthesis with robotic assistance, respectively. No intraoperative neurovascular injuries and postoperative infection occurred. All patients were followed up for at least 12 months. The average operation time of posterior pelvic ring was 111.4 min, with the mean intraoperative bleeding of 110.5 ml. A total of 58 pedicle and iliosacral screws were implanted with robotic assistance. Of those, 52 screws were in the cancellous bone except 4 pedicle and 2 iliosacral screws cutting the cortical bone. The angulation and displacement deviations of the screws were 4.2° ± 2.5° and 1.7 ± 0.9 mm, respectively. The average displacement of the sacral fracture was reduced from 19.7 mm preoperatively to 3.1 mm postoperatively. According to Matta's criterion, the reduction quality was graded as "excellent" in 13 patients and "good" in 8. All sacral fractures healed within 6 months except one fracture with nonunion. The mean Majeed score at the last follow-up was 89.6. CONCLUSIONS: Robot-aided triangular osteosynthesis combined with close reduction provide a safe and reliable option for percutaneous treatment of the fresh VUSF, with a high accuracy of iliosacral and pedicle screw implantation except insertion of iliac screws. Meanwhile, the technique may help to reduce incision-related complications.

Comparative retrospective study of triangular osteosynthesis with and without robotic assistance for unilateral unstable sacral fractures combined with lumbosacral junction injuries.

BACKGROUND: To compare the clinical efficacy of unilateral unstable sacral fractures (USFs) involving the lumbosacral region treated with and without robot-aided triangular osteosynthesis (TOS). METHODS: Patients of the unilateral USF combined with the ipsilateral lumbosacral junction injury (LSJI) treated with TOS were retrospectively analyzed and divided into two groups: the robot group (TOS with robotic assistance) and the conventional group (TOS with open procedure). Screw placement was assessed using the modified Gras criterion. Patients were followed up with routine visits for clinical and radiographic examinations. At the final follow-up, clinical outcomes were recorded and scored using the Majeed scoring system. RESULTS: Eleven patients in the robot group and seventeen patients in the conventional group were recruited into this study. Significant differences in surgical bleeding (P < 0.001) and fluoroscopy time (P = 0.002) were noted between the two groups. Operation time (P = 0.027) and fracture healing time (P = 0.041) was shorter in the robot group. There was no difference in postoperative residual displacement between the two groups (P = 0.971). According to the modified Gras criterion, the percentages of grade I for sacroiliac screws in the two groups were 90.9% (10/11) and 70.6% (12/17), and for pedicle screws were 100% (11/11) and 100% (17/17), respectively. The rate of incision-related complications was 0% (0/11) in the robot group and 11.8% (2/17) in the conventional group. Statistical differences were shown on the Majeed criterion (P = 0.039), with higher scores in the robot group. CONCLUSION: TOS with robotic assistance for the treatment of unilateral USFs combined with ipsilateral LSJIs is safe and feasible, with the advantages of less radiation exposure and fewer incision-related complications.

The Kocher-Langenbeck approach combined with robot-aided percutaneous anterior column screw fixation for transverse-oriented acetabular fractures: a retrospective study.

OBJECTIVE: Transverse-oriented acetabular fractures (TOAFs), including transverse, transverse with posterior wall and T-shaped fractures, are always challenging for double-column reduction and fixation with minimally invasive method. The purpose of this study is to compare the therapeutic effects of robot-aided percutaneous anterior column screw fixation versus minimally invasive anterior plate fixation for TOAFs based on the Kocher-Langenbeck (K-L) approach. METHODS: Patients suffering TOAFs that were fixed by robot-aided percutaneous anterior column screw fixation or minimally invasive anterior plate fixation associated with posterior fixation via the K-L approach were divided into two groups: group A (screw fixation) and group B (plate fixation). Surgical time, blood loss, incision length for anterior fixation and complications were recorded. Fracture reduction quality was evaluated using criteria described by Matta. Fracture healing was assessed on the series of pelvic radiographs at each follow-up. Functional outcomes were investigated using the modified Postel Merle D'Aubigne score at the final follow-up. RESULTS: Twenty-nine patients with TOAFs, including 12 patients in group A and 17 patients in group B, were evaluated for study eligibility. The mean surgical time of anterior fracture fixation was 18.7 ± 4.6 min in group A and 33.4 ± 5.0 min in group B (P < 0.001). The amount of intraoperative blood loss was 615.6 ± 178.7 ml in group A and 719.3 ± 199.0 ml in group B (P < 0.001). Incision length for anterior fixation was 9.0 ± 1.8 mm in group A and 81.2 ± 7.3 mm in group B (P < 0.001). The complications related to the surgery of anterior column only occurred in group B (lateral femoral cutaneous nerve palsy in 1 patient and groin discomfort in 1 patient). No significant differences in reduction quality, hospital stay, fracture healing time and functional results were noted between the two groups. CONCLUSION: The K-L approach combined with robot-aided anterior column screw fixation is a safe and effective option for TOAFs. Compared with minimally invasive anterior plate fixation, robot-aided screw fixation has obvious advantages on surgical time, blood loss, and invasiveness. The K-L approach combined with minimally invasive anterior plate fixation can also be a reliable alternative for TOAFs, with the similar reduction quality and functional results.

Robot-Aided Minimally Invasive Lumbopelvic Fixation in Treatment of Traumatic Spinopelvic Dissociation.

OBJECTIVE: To investigate the surgical strategy, safety, and efficacy of close reduction and robot-aided minimally invasive lumbopelvic fixation in treatment of traumatic spinopelvic dissociation. METHODS: Data of 32 patients (21 males and 11 females) with traumatic spinopelvic dissociation treated by lumbopelvic fixation with robot-aided minimally invasive technique or conventional open procedure in our institution from March 2010 to April 2019 were retrospectively analyzed, and divided into robot group and control group. Intraoperative blood loss, surgical time, fluoroscopy frequency, total drilling times, infection rate, hospitalization time, and sacral fracture healing time were reviewed. Radiographs and computed tomography (CT) scans were totally acquired to evaluate the reduction quality, residual fracture displacement, and Gras classification on screws insertion after surgery. According to the Majeed scoring system, functional outcome was assessed for each patient at the final follow-up. RESULTS: There were 12 patients in the robot group and 20 patients in the control group with no significant difference about the demographic data. The average surgical time was 148.3 ± 40.5 min with intraoperative blood loss of 142.5±36.7 mL in the robot group and 185.0 ± 47.8 min with 612.5 ± 182.7 mL in the control group (P = 0.034, P = 0.000). The robot group had a shorter mean hospitalization time at 19.9 ± 7.0 days compared to the control group with 28.6 ± 5.4 days (P = 0.010). The fluoroscopy frequency was 35.4 ± 3.0 in the robot group and 45.5 ± 3.6 in the control group (P = 0.000) and total drilling times were 7.1 ± 1.1 and 9.6 ± 1.3 (P = 0.000), respectively. The infection rate was 0% (0/12) in the robot group and 15% (3/20) in the control group (P = 0.159). According to the Gras classification on screw positioning, there were 11 cases in Grade I and 1 case in Grade II in the robot group, and 14 cases in Grade I and 6 cases in Grade II in the control group. All the patients were followed up consecutively for at least 12 months, with an average follow-up period of 17.1 ± 3.6 months. All sacral fractures healed with an average time of 3.8 ± 0.6 months in the robot group and 4.7 ± 0.7 months in the control group (P = 0.000). According to Majeed functional assessment investigation, the mean score of the patients was 87.2 ± 4.0 in the robot group and 83.1 ± 4.5 in the control group (P = 0.015). CONCLUSIONS: Robot-aided minimally invasive lumbopelvic fixation for traumatic spinopelvic dissociation is a safe and feasible option with advantages of less intraoperative blood loss, less radiation damage, less hospitalization time, and better functional outcome.

Internal Fixation of Complicated Acetabular Fractures Directed by Preoperative Surgery with 3D Printing Models.

The purpose of this article is to evaluate the efficacy and feasibility of preoperative surgery with 3D printing-assisted internal fixation of complicated acetabular fractures. A retrospective case review was performed for the above surgical procedure. A 23-year-old man was confirmed by radiological examination to have fractures of multiple ribs, with hemopneumothorax and communicated fractures of the left acetabulum. According to the Letounel and Judet classification, T-shaped fracture involving posterior wall was diagnosed. A 3D printing pelvic model was established using CT digital imaging and communications in medicine (DICOM) data preoperatively, with which surgical procedures were simulated in preoperative surgery to confirm the sequence of the reduction and fixation as well as the position and length of the implants. Open reduction with internal fixation (ORIF) of the acetabular fracture using modified ilioinguinal and Kocher-Langenbeck approaches was performed 25 days after injury. Plates that had been pre-bent in the preoperative surgery were positioned and screws were tightened in the directions determined in the preoperative planning following satisfactory reduction. The duration of the operation was 170 min and blood loss was 900 mL. Postoperative X-rays showed that anatomical reduction of the acetabulum was achieved and the hip joint was congruous. The position and length of the implants were not different when compared with those in preoperative surgery on 3D printing models. We believe that preoperative surgery using 3D printing models is beneficial for confirming the reduction and fixation sequence, determining the reduction quality, shortening the operative time, minimizing preoperative difficulties, and predicting the prognosis for complicated fractures of acetabulam.

[Detection of protein secretion and expression and osteogenic activity of adipose tissue-derived stem cells after in vitro transfection of vascular endothelial growth factor].

OBJECTIVE: To examine vascular endothelial growth factor (VEGF) protein secretion and expression and explore the osteogenic activity of adipose tissue-derived stem cells (ADSCs) after transfection of human VEGF. METHODS: The ADSCs were isolated from human adipose tissue after the digestion of collagenase.After identification by flow cytometry, the cells were cultured and passaged in nutritive medium. Gene sequence encoding human VEGF mature peptide was obtained by Trizol reagent method from human vascular tissue. Target gene VEGF was connected with bicistronic expression vector containing green fluorescent protein to form pSELECT-GFP zeo-VEGF for transfecting 2nd, 3rd, 4th, 5th generation ADSCs mediated by liposome. The transfection results were verified under fluorescence microscope. VEGF protein secretion by transfected cells was detected by enzyme-linked immunosorbent assay (ELISA). Second-generation transfected ADSCs were cultured under osteogenic conditions.The supernatant levels of alkaline phosphatase (ALP) and osteocalcin (OC) were detected. RESULTS: Liposome-mediated VEGF target gene fragment could transfect ADSCs successfully. ELISA quantitative detection showed that VEGF mRNA expression levels in supernatant of the transfected group was significantly higher than the control group. And there were significant differences. After osteogenic culturing, the detections of ELISA, real-time PCR and Western blot showed that the secretion of ALP and OC of VEGF transfected group was significantly higher than that of empty vector transfected and blank cell groups.And there were significant differences (P < 0.01). CONCLUSION: After transfected by liposome-mediated VEGF target gene fragment, human ADSCs can express biologically active VEGF mRNA in vitro continuously and effectively. Directional differentiation capacity of transfected ADSCs is significantly enhanced.

5-Anilino-3-benzyl-sulfanyl-6-(3-chloro-anilino)-1-phenyl-1H-pyrazolo-[3,4-d]pyrimidin-4(5H)-one.

In the title compound, C(30)H(23)ClN(6)OS, the benzyl, the 3-chloro-anilino, the phenyl and the anilino groups form dihedral angles of 85.95 (6), 29.63 (7), 28.55 (1) and 87.48 (6)°, respectively, with the pyrazolo-[3,4-d]pyrimidine unit [maximum deviation = 0.052 (2) Å]. An intra-molecular N-H⋯N hydrogen bond occurs. The crystal structure features N-H⋯O hydrogen bonds.

Synthesis and herbicidal activity of novel pyrazolo[3,4-d]pyrimidin-4-one derivatives containing aryloxyphenoxypropionate moieties.

The 6-(4-alkoxycarbonylalkoxy)phenoxy-3-alkylthio(alkylsulfonyl)-1-phenyl-5-(substituted phenyl)pyrazolo[3,4-d]pyrimidin-4-ones 6 and 7 have been synthesized via the tandem aza-Wittig and annulation reactions of the corresponding iminophosphoranes 4, aromatic isocyanates, and substituted phenols 2 in 52-98% yields. Their structures were clearly verified by spectroscopic data (IR, (1)H NMR, (13)C NMR, MS, and elemental analysis or X-ray diffraction crystallography). And the results of preliminary bioassay indicated that these title compounds possess potential herbicidal activity against the root of rape and barnyard grass.

Stereoselective synthesis and antifungal activities of (E)-alpha-(methoxyimino)benzeneacetate derivatives containing 1,3,5-substituted pyrazole ring.

Thirteen novel (E)-alpha-(methoxyimino)benzeneacetate derivatives, the analogues of strobilurins, which contain two pharmacophoric substructures of the methyl (E)-methoxyiminoacetate moiety and 1,3,5-substituted pyrazole ring, were stereoselectively synthesized. It was found that the coupling reaction could give stereoselectively (E:Z ca. 14:1) the key intermediate material (E)-methyl 2-(hydroxyimino)-2-o-tolyl acetate (2). An X-ray crystallographic structure determination was carried out in a representative product. The preliminary bioassays indicated that all of the compounds 1 showed potent fungicidal activity against Rhizoctonia solani, Botrytis cinereapers, Gibberella zeae, Physalospora piricola, and Bipolaris mayclis.