OBJECTIVE To form an expert consensus addressing clinical issues regarding the use of parenteral direct thrombin inhibitors （DTIs） in special populations. METHODS Led by the Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital（the Affiliated Hospital of UESTC）， a multidisciplinary working group was formed comprising experts from multiple fields， including clinical pharmacy， cardiac surgery， obstetrics， pediatrics and evidence-based medicine. Through literature review and the Delphi method， clinical questions regarding the efficacy and safety of parenteral DTIs used in special populations were identified. A structured design was adopted using the “Population-Intervention-Comparison-Outcome” （PICO） framework；systematic searches were conducted in CJFD， PubMed， Embase and other databases. Relevant evidence from randomized controlled trials，cohort studies and systematic reviews were included and synthesized. Evidence quality was assessed using the Grading of Recommendations Assessment，Development and Evaluation （GRADE） approach， and recommendations were formulated through three rounds of Delphi surveys and expert consensus meetings. RESULTS &CONCLUSIONS Seven clinical questions were ultimately selected （with a consensus rate exceeding 90%）， resulting in the formulation of seven recommendations on the use of parenteral DTIs in special populations， including children， pregnant women， patients with hepatic or renal impairment， patients with mesenteric venous thrombosis， and individuals with thrombophilia. These recommendations clarify the preferred agents， dosing ranges， monitoring parameters， and safety management strategies for parenteral DTIs in these special populations. This expert consensus， which is formulated based on the best available evidence， provides evidence-based guidance for standardized and individualized use of parenteral DTIs in special populations.

Objective:To evaluate the efficacy of 3D printing technology combined with computer navigation-assisted screw implantation in the treatment of atlantoaxial instability (AAI) complicated by vertebral artery anomalies.Methods:A retrospective case series study was conducted to analyze the clinical data of 23 patients with AAI complicated by vertebral artery anomalies who were admitted to Honghui Hospital of Xi′an Jiaotong University between January 2019 and January 2023, including 10 males and 13 females, aged 19-70 years [(51.0±13.3)years]. Vertebral artery anomalies were categorized into unilateral high-riding vertebral artery with unilateral dominance ( n=14), bilateral high-riding vertebral arteries with unilateral dominance ( n=6), and ponticulus posticus ( n=3). All the patients underwent preoperative planning using a 3D-printed model of the atlantoaxial complex with the vertebral artery, followed by posterior atlantoaxial pedicle screw fixation with computer-assisted navigation. Operative duration and intraoperative blood loss were recorded. The accuracy of pedicle screw placement was assessed at 3 days postoperatively using the Gertzbein-Robbins classification. Visual analogue scale (VAS) scores and Japanese Orthopedic Association (JOA) scores were evaluated preoperatively, at 3 days, 3 months postoperatively, and at the last follow-up. Bony fusion was assessed using cervical CT with 3D reconstruction at the last follow-up. Complications were also observed. Results:All the patients were followed up for 12-19 months [(15.1±1.9)months]. The operative duration was 125-167 minutes [(140.6±10.9)minutes] and intraoperative blood loss was 200-600 ml [(295.7±77.8)ml]. At 3 days postoperatively, all the 66 pedicle screws were safely placed, with 60 screws (91%) rated as Gertzbein-Robbins Grade 0 and 6 screws (9%) as Grade 1. At 3 days and 3 months postoperatively, and at the last follow-up, the VAS scores were (4.0±1.0)points, (2.0±0.6)points, and (1.3±0.5)points, and the JOA scores were (14.2±1.2)points, (16.0±0.8)points, and (16.6±0.5)points, both of which were not only significantly improved compared with preoperative (5.6±1.3)points and (12.8±1.5)points, but also further improved over time ( P<0.05). At the last follow-up, 22 patients (96%) achieved satisfactory atlantoaxial bony fusion. No vertebral artery injury, spinal cord or nerve injury, cerebrospinal fluid leakage, or screw loosening were observed in any patients. Conclusion:For patients with AAI complicated by vertebral artery anomalies, 3D printing combined with computer navigation-assisted navigation for atlantoaxial pedicle screw implantation offers multiple advantages, including minimal surgical trauma, high screw placement accuracy, pain relief, neurological function improvement, high fusion rate, and lowered incidence of complications.

Objective:To compare the efficacy of robot system-assisted versus freehand screw revision for ankylosing spondylitis (AS) with lower cervical fractures.Methods:A multicenter retrospective cohort study was conducted to analyze the clinical data of 57 patients with AS combined with lower cervical fractures admitted to Honghui Hospital Affiliated to Xi'an Jiaotong University School of Medicine, Henan Provincial People's Hospital, Zhengzhou Orthopedic Hospital, and Qilu Hospital of Shandong University, including 46 males and 11 females, aged 38-77 years [(65.4±9.5)years]. Injury segments involved C 3 in 7 patients, C 4 in 13, C 5 in 25, C 6 in 10, and C 7 in 2. All the patients underwent revision surgery, among whom, 22 patients were treated with robot system-assisted cervical pedicle screw placement (robot nailing group, with 190 screws), and 35 with freehand cervical pedicle screw placement (freehand nailing group, with 300 screws). The operative duration, intraoperative bleeding volume, frequency of intraoperative fluoroscopy, incision length, and length of hospital stay of the two groups were compared; the time of single nscrew insertion, the number of single nail revisions, the distance between screws and the anterior cortex, the accuracy of screw placement of grade 0 and grade 0+1 were recorded in the two groups. The visual analogue scale (VAS), Japanese Orthopedic Society (JOA) score, neck dysfunction index (NDI), American Spine Injury Association (ASIA) classification before operation, at 3 days, 3 months after operation and at the last follow-up were compared between the two groups. The complication rate was also noted. Results:All the patients were followed up for 12-16 months [(14.3±2.1)months]. The operative duration, intraoperative bleeding volume, and frequency of intraoperative fluoroscopy were (186.4±12.9)minutes, (486.1±68.6)ml, and (3.4±1.3)times in the robot nailing group, which were shorter or less than (206.7±14.4)minutes, (660.3±45.2)ml, and (13.5±3.6)times in the freehand nailing group ( P<0.01). The incision length was (9.4±2.4)cm in the robot nailing group, longer than (5.6±1.2)cm in the freehand nailing group ( P<0.01), and the length of hospital stay was (3.7±0.4)days, shorter than (4.4±1.4)days in the freehand nailing group ( P<0.01). The length of single nail insertion, the number of single nail revision, and the distance between the screws and the front cortex were (6.5±0.4)minutes, (1.1±0.1)times, and (3.5±1.3)mm in the robot nailing group, which were shorter or less than (11.6±0.2)minutes, (1.5±0.2)times, and (12.4±4.7)mm in the freehand nailing group ( P<0.01). The accuracy of the screw placement in the robot nailing group was 90.0% (171/190) and 95.8% (182/190) with level 0 and 0+1 screws, better than 80.0% (240/300) and 89.0% (267/300) in the freehand nailing group ( P<0.05). There was no significant difference in VAS, JOA score, NDI, or ASIA grading between the two groups before operation ( P>0.05). The VAS, JOA, and NDI scores at 3 days after operation were (3.1±0.6)points, (12.1±1.2)points, and (15.6±2.9)points, respectively in the robot nailing group, which were better than (5.0±1.4)points, (11.3±1.1)points and (22.5±3.7)points, respectively in the freehand nailing group ( P<0.05). No statistically significant difference was observed in the ASIA grade between the two groups at 3 days after operation ( P>0.05). There were no significant differences in VAS, JOA, NDI scores, or ASIA grading between the two groups at 3 months after operation and at the last follow-up ( P>0.05). Compared with those before operation, the VAS, JOA, NDI scores, and ASIA grading were significantly improved at 3 days, 3 months after operation and at the last follow-up in the two groups, which were further improved with the passage of time. Two patients in the robot nailing group had pneumonia, with a complication rate of 9% (2/22), while 2 patients in the freehand nailing group had dural sac rupture and cerebrospinal fluid leakage and 3 had lung infection after operation, with a complication rate of 14% (5/35) ( P<0.05). Conclusion:Compared with freehand nailing, the robot system-assisted nailing revision for AS with lower cervical fracture has more advantages in terms of the operative duration, length of hospital stay, intraoperative bleeding volume, frequency of intraoperative fluoroscopy nailing speed and accuracy, screw holding force, early pain relief, function restoration, and complication rate, despite longer surgical incision.

Objective:To compare the efficacy of laminoplasty via the intermuscular approach or posterior midline approach for treating spinal cord injury without radiographic abnormality (SCIWORA).Methods:A multi-center retrospective cohort study was conducted to analyze the clinical data of 135 patients with SCIWORA admitted to Honghui Hospital Affiliated to Xi'an Jiaotong University School of Medicine, Xi'an No.5 Hospital, Henan Provincial People's Hospital, Zhengzhou Orthopedic Hospital, Xuanwu Hospital of Capital Medical University from February 2021 to June 2023, including 75 males and 60 females, aged 35-78 years [(55.3±8.1)years]. The injury segments involved C 3-C 6. All the patients underwent posterior cervical open-door laminoplasty, among whom 70 patients were treated via the intermuscular approach (intermuscular group) and 65 via the posterior midline approach (posterior midline group). The operation duration, intraoperative blood loss, postoperative drainage volume, and length of hospital stay were recorded. The visual analogue scale (VAS) score, Japanese Orthopedic Association (JOA) score, neck disability index (NDI), Barthel index, cervical Cobb angle, and cervical range of motion (ROM) were measured preoperatively, at 3, 6, 12 months postoperatively and at the final follow-up. The American Spinal Injury Association (ASIA) scale was evaluated preoperatively, at 3, 12 months postoperatively and at the final follow-up. The postoperative complication rate was recorded as well. Results:All the patients were followed up for 15-19 months [(16.3±1.6)months]. The operation duration, intraoperative blood loss, postoperative drainage and length of hospital stay were (125.0±23.0)minutes, (210.4±34.8)ml, and (165.3±23.7)ml, and (5.3±0.1)days in the intermuscular group, which were significantly shorter or less than (168.0±27.6)minutes, (260.2±45.3)ml, (196.4±31.6)ml, and (6.4±0.2)days in the posterior midline group ( P<0.01). The preoperative VAS score, JOA score, NDI and Barthel index showed no significant differences between the two groups ( P>0.05). The VAS score and JOA score also showed no significant differences between the two groups at 3, 6, 12 months postoperatively or at the final follow-up ( P>0.05). The NDI and Barthel index also showed no significant differences between the two groups at 3 months postoperatively ( P>0.05). At 6, 12 months postoperatively and at the final follow-up, the NDI were (15.4±2.5)points, (11.8±2.1)points and (8.6±1.5)points in the intermuscular group, significantly lower than (19.1±3.4)points, (14.3±2.4)points and (11.9±1.4)points in the posterior midline group ( P<0.01). At 6, 12 months postoperatively and at the final follow-up, the Barthel index were (71.4±6.2)points, (83.4±5.8)points and (89.2±7.1)points in the intermuscular group, significantly higher than (59.6±4.7)points, (74.2±3.9)points and (78.8±6.2)points in the posterior midline group ( P<0.01). Both groups showed significant improvements in VAS score, JOA score, NDI and Barthel index at 3, 6, 12 months postoperatively and at the final follow-up when compared to those preoperatively ( P<0.05). Among them, the VAS score, NDI and Barthel index were further improved over time ( P<0.05). Simultaneously, the JOA score was significantly improved at 6, 12 months postoperatively and at the last follow-up when compared to that at 3 months postoperatively ( P<0.05), with no significant difference at later time points between the two groups ( P>0.05). The preoperative cervical Cobb angle and ROM showed no significant differences between the two groups ( P>0.05). There was no significant difference in the Cobb angle between the two groups at 3, 6 or 12 months postoperatively ( P>0.05), while it was (13.6±2.4)° in the intermuscular group at the final follow-up, significantly larger than (10.4±2.8)° in the posterior midline group ( P<0.01). At 3, 6, 12 months postoperatively and at the final follow-up, the cervical ROM were (34.1±6.4)°, (32.6±7.3)°, (31.8±9.1)° and (29.6±8.7)° in the intermuscular group, significantly larger than (23.7±8.3)°, (22.3±7.8)°, (22.5±8.1)° and (20.6±9.3)° in the posterior midline group ( P<0.01). In the intermuscular group, the cervical Cobb angle showed no significant changes at 3, 6, 12 months postoperatively and at the final follow-up when compared to those preoperatively ( P>0.05). In the posterior midline group, the Cobb angles were significantly reduced at 3, 6, 12 months postoperatively and at the final follow-up when compared to those preoperatively ( P<0.05), showing significant decrease at 12 months postoperatively and at the final follow-up from those at 3, 6 months postoperatively ( P<0.05), no significant difference at 6 months postoperatively from that at 3 months postoperatively ( P>0.05), and significant decrease at the final follow-up from that at 12 months postoperatively ( P>0.05). In the intermuscular group, the cervical ROM were significantly improved at 3, 6, 12 months postoperatively and at the final follow-up when compared to those preoperatively and showed further improvement over time ( P<0.05). In the posterior midline group, the cervical ROM were significantly improved at 3, 6, 12 months postoperatively and at the final follow-up when compared to those preoperatively ( P<0.05), showing significant decreases at 6, 12 months postoperatively and at the final follow-up from that at 3 months postoperatively ( P<0.05), significant decreases at the final follow-up from those at 6, 12 months postoperatively ( P<0.05), and no significant difference at 12 months postoperatively from that at 6 months postoperatively ( P>0.05). The ASIA grades showed no significant difference between the two groups preoperatively, at 3, 12 months postoperatively and at the final follow-up ( P>0.05) , but were gradually improved over time in both groups ( P<0.05). The postoperative complication rate was 9%(6/70) in the intermuscular group, significantly lower than 48%(31/65) in the posterior midline group ( P<0.01). Conclusion:Compared to the posterior midline approach, the intermuscular approach for laminoplasty in patients with SCIWORA possesses advantages, including shorter operative time and length of hospital stay, reduced intraoperative blood loss and postoperative drainage, less postoperative neck disability, higher daily life quality, better long-term preservation of cervical lordosis and motion, and a lower complication rate.

Paraplegia caused by spinal cord injury is a serious neurological complication, for which surgery is currently the main treatment method. Due to different surgical approaches, patients are usually expected to maintain a passive prone position for a long time or switch between the supine and prone positions. Affected by multiple factors such as neurogenic sensory disorders, pathological changes in muscle tone and operative duration, the risk of intraoperative acquired pressure injury (IAPI) is significantly increased. Current clinical prevention strategies for IAPI in these patients predominantly focus on localized pressure relief during positioning, lacking systematic, standardized comprehensive prevention protocols or evidence-based guidelines. To address it, Department of Nursing, Orthopedics Branch, China International Exchange and Promotive Association for Medical and Health Care, Spinal Trauma Professional Committee, Orthopedics Branch, Chinese Medical Doctor Association, Nursing Group of Spine and Spinal Cord Professional Committee of Chinese Association of Rehabilitation Medicine organized experts in relevant fields to formulate Guideline for the prevention of intraoperative acquired pressure injury in paraplegic patients with spinal cord injury ( version 2025), based on evidence-based medical evidence and latest research results and clinical practice at home and abroad. Eleven recommendations were put forward from the aspects of preoperative risk assessment, intraoperative prevention strategies, postoperative handover and monitoring, and supportive mechanisms for IAPI prevention, aiming to standardize the prevention measures and management strategies of IAPI in paraplegic patients with spinal cord injury and accelerate the recovery of patients and improve the therapeutic effect.

Objective:To compare the clinical efficacy of navigation system and orthopedic robot-assisted nail placement in the treatment of lower cervical fracture and dislocation.Methods:A retrospective cohort study was conducted to analyze the clinical data of 49 patients with fracture and dislocation of the lower cervical spine who were admitted to Honghui Hospital, Xi′an Jiaotong University School of Medicine from May 2021 to October 2022, including 38 males and 11 females, aged 29-61 years [(39.3±7.3)years]. Injury segments involved C 3 in 12 patients, C 4 in 11, C 5 in 8, C 6 in 9 and C 7 in 9. Twenty-one patients were treated with S8 navigation system (navigation group, 84 screws), and 28 with TINAVI orthopedic robot (robot group, 112 screws). The two groups were compared in terms of the total surgical duration, single screw placement time, total screw placement time, distance between the screw and the anterior cortex, incision length, intraoperative radiation dose, intraoperative blood loss and length of hospital stay. The height of intervertebral space, Cobb angle, sliding distance between vertebral bodies and American Spinal Injury Association (ASIA) grade were assessed before surgery and at 3 days after surgery. Visual analogue scale (VAS), Japanese Orthopedic Association (JOA) score and neck dysfunction index (NDI) before surgery, at 3 days, 3 months after surgery and at the last follow-up were compared. The accuracy of screw placement, intraoperative invasion rate of adjacent facet joints and rate of postoperative complications (infection, screw loosening, etc.) were evaluated. Results:All the patients were followed up for 12-16 months [(13.6±1.9)months]. In the navigation group, the total surgical duration, distance from the screw to the anterior cortex and the intraoperative radiation dose were (236.2±30.6)minutes, (2.0±0.2)mm and (374.3±90.3)mGy respectively, which were significantly shorter or less than those in the robot group [(278.4±20.7)minutes, (10.6±2.9)mm and (448.4±77.9)mGy] ( P<0.01). The single screw placement time, total screw placement time, incision length and intraoperative blood loss were (3.5±0.4)minutes, (23.9±0.5)minutes, (9.1±2.4)cm and (422.2±30.4)ml respectively, which were significantly longer or more than those in the robot group [(2.6±0.2)minutes, (17.9±0.7)minutes, (6.6±2.6)cm and (360.3±56.3)ml] ( P<0.01). There was no significant difference in the length of hospital stay between the two groups ( P>0.05). No significant differences were observed in the height of the intervertebral space, Cobb angle, sliding distance between the vertebral bodies and ASIA grade between the two groups ( P>0.05). At 3 days after surgery, the height of intervertebral space, Cobb angle, sliding distance between vertebral bodies and ASIA grade in both groups were significantly improved when compared with those before surgery ( P<0.05 or 0.01). There were no significant differences in VAS, JOA scores or NDI between the two groups before surgery, at 3 days, 3 months after surgery and at the last follow-up ( P>0.05). The VAS, JOA scores and NDI in both groups were gradually improved at 3 days, 3 months and at the last follow-up after surgery when compared with those before surgery ( P<0.05). There was no significant difference in the accuracy of screw placement of levels 0 and 0+1 between the two groups ( P>0.05). No significant difference in the intraoperative invasion rate of adjacent facet joints between the two groups was found ( P>0.05). There were no serious complications such as infection or screw loosening after surgery in both groups. Conclusions:For lower cervical fracture and dislocation, although there are more advantages in total surgical duration, screw holding force and radiation control regarding the navigation system, and more outstanding performance in screw placement efficiency, incision length and intraoperative blood loss regarding the orthopedic robot, both of them can effectively rebuild the cervical structure, improve neurological function, relieve postoperative pain, improve screw placement accuracy and reduce facet joint injury and serious complications. Selection of the best auxiliary screw placement system should comprehensively consider patients′ conditions and the experience of the surgical team.

Objective:To evaluate the efficacy of 3D printing technology combined with computer navigation-assisted screw implantation in the treatment of atlantoaxial instability (AAI) complicated by vertebral artery anomalies.Methods:A retrospective case series study was conducted to analyze the clinical data of 23 patients with AAI complicated by vertebral artery anomalies who were admitted to Honghui Hospital of Xi′an Jiaotong University between January 2019 and January 2023, including 10 males and 13 females, aged 19-70 years [(51.0±13.3)years]. Vertebral artery anomalies were categorized into unilateral high-riding vertebral artery with unilateral dominance ( n=14), bilateral high-riding vertebral arteries with unilateral dominance ( n=6), and ponticulus posticus ( n=3). All the patients underwent preoperative planning using a 3D-printed model of the atlantoaxial complex with the vertebral artery, followed by posterior atlantoaxial pedicle screw fixation with computer-assisted navigation. Operative duration and intraoperative blood loss were recorded. The accuracy of pedicle screw placement was assessed at 3 days postoperatively using the Gertzbein-Robbins classification. Visual analogue scale (VAS) scores and Japanese Orthopedic Association (JOA) scores were evaluated preoperatively, at 3 days, 3 months postoperatively, and at the last follow-up. Bony fusion was assessed using cervical CT with 3D reconstruction at the last follow-up. Complications were also observed. Results:All the patients were followed up for 12-19 months [(15.1±1.9)months]. The operative duration was 125-167 minutes [(140.6±10.9)minutes] and intraoperative blood loss was 200-600 ml [(295.7±77.8)ml]. At 3 days postoperatively, all the 66 pedicle screws were safely placed, with 60 screws (91%) rated as Gertzbein-Robbins Grade 0 and 6 screws (9%) as Grade 1. At 3 days and 3 months postoperatively, and at the last follow-up, the VAS scores were (4.0±1.0)points, (2.0±0.6)points, and (1.3±0.5)points, and the JOA scores were (14.2±1.2)points, (16.0±0.8)points, and (16.6±0.5)points, both of which were not only significantly improved compared with preoperative (5.6±1.3)points and (12.8±1.5)points, but also further improved over time ( P<0.05). At the last follow-up, 22 patients (96%) achieved satisfactory atlantoaxial bony fusion. No vertebral artery injury, spinal cord or nerve injury, cerebrospinal fluid leakage, or screw loosening were observed in any patients. Conclusion:For patients with AAI complicated by vertebral artery anomalies, 3D printing combined with computer navigation-assisted navigation for atlantoaxial pedicle screw implantation offers multiple advantages, including minimal surgical trauma, high screw placement accuracy, pain relief, neurological function improvement, high fusion rate, and lowered incidence of complications.

Objective:To compare the efficacy of robot system-assisted versus freehand screw revision for ankylosing spondylitis (AS) with lower cervical fractures.Methods:A multicenter retrospective cohort study was conducted to analyze the clinical data of 57 patients with AS combined with lower cervical fractures admitted to Honghui Hospital Affiliated to Xi'an Jiaotong University School of Medicine, Henan Provincial People's Hospital, Zhengzhou Orthopedic Hospital, and Qilu Hospital of Shandong University, including 46 males and 11 females, aged 38-77 years [(65.4±9.5)years]. Injury segments involved C 3 in 7 patients, C 4 in 13, C 5 in 25, C 6 in 10, and C 7 in 2. All the patients underwent revision surgery, among whom, 22 patients were treated with robot system-assisted cervical pedicle screw placement (robot nailing group, with 190 screws), and 35 with freehand cervical pedicle screw placement (freehand nailing group, with 300 screws). The operative duration, intraoperative bleeding volume, frequency of intraoperative fluoroscopy, incision length, and length of hospital stay of the two groups were compared; the time of single nscrew insertion, the number of single nail revisions, the distance between screws and the anterior cortex, the accuracy of screw placement of grade 0 and grade 0+1 were recorded in the two groups. The visual analogue scale (VAS), Japanese Orthopedic Society (JOA) score, neck dysfunction index (NDI), American Spine Injury Association (ASIA) classification before operation, at 3 days, 3 months after operation and at the last follow-up were compared between the two groups. The complication rate was also noted. Results:All the patients were followed up for 12-16 months [(14.3±2.1)months]. The operative duration, intraoperative bleeding volume, and frequency of intraoperative fluoroscopy were (186.4±12.9)minutes, (486.1±68.6)ml, and (3.4±1.3)times in the robot nailing group, which were shorter or less than (206.7±14.4)minutes, (660.3±45.2)ml, and (13.5±3.6)times in the freehand nailing group ( P<0.01). The incision length was (9.4±2.4)cm in the robot nailing group, longer than (5.6±1.2)cm in the freehand nailing group ( P<0.01), and the length of hospital stay was (3.7±0.4)days, shorter than (4.4±1.4)days in the freehand nailing group ( P<0.01). The length of single nail insertion, the number of single nail revision, and the distance between the screws and the front cortex were (6.5±0.4)minutes, (1.1±0.1)times, and (3.5±1.3)mm in the robot nailing group, which were shorter or less than (11.6±0.2)minutes, (1.5±0.2)times, and (12.4±4.7)mm in the freehand nailing group ( P<0.01). The accuracy of the screw placement in the robot nailing group was 90.0% (171/190) and 95.8% (182/190) with level 0 and 0+1 screws, better than 80.0% (240/300) and 89.0% (267/300) in the freehand nailing group ( P<0.05). There was no significant difference in VAS, JOA score, NDI, or ASIA grading between the two groups before operation ( P>0.05). The VAS, JOA, and NDI scores at 3 days after operation were (3.1±0.6)points, (12.1±1.2)points, and (15.6±2.9)points, respectively in the robot nailing group, which were better than (5.0±1.4)points, (11.3±1.1)points and (22.5±3.7)points, respectively in the freehand nailing group ( P<0.05). No statistically significant difference was observed in the ASIA grade between the two groups at 3 days after operation ( P>0.05). There were no significant differences in VAS, JOA, NDI scores, or ASIA grading between the two groups at 3 months after operation and at the last follow-up ( P>0.05). Compared with those before operation, the VAS, JOA, NDI scores, and ASIA grading were significantly improved at 3 days, 3 months after operation and at the last follow-up in the two groups, which were further improved with the passage of time. Two patients in the robot nailing group had pneumonia, with a complication rate of 9% (2/22), while 2 patients in the freehand nailing group had dural sac rupture and cerebrospinal fluid leakage and 3 had lung infection after operation, with a complication rate of 14% (5/35) ( P<0.05). Conclusion:Compared with freehand nailing, the robot system-assisted nailing revision for AS with lower cervical fracture has more advantages in terms of the operative duration, length of hospital stay, intraoperative bleeding volume, frequency of intraoperative fluoroscopy nailing speed and accuracy, screw holding force, early pain relief, function restoration, and complication rate, despite longer surgical incision.

Objective:To compare the efficacy of laminoplasty via the intermuscular approach or posterior midline approach for treating spinal cord injury without radiographic abnormality (SCIWORA).Methods:A multi-center retrospective cohort study was conducted to analyze the clinical data of 135 patients with SCIWORA admitted to Honghui Hospital Affiliated to Xi'an Jiaotong University School of Medicine, Xi'an No.5 Hospital, Henan Provincial People's Hospital, Zhengzhou Orthopedic Hospital, Xuanwu Hospital of Capital Medical University from February 2021 to June 2023, including 75 males and 60 females, aged 35-78 years [(55.3±8.1)years]. The injury segments involved C 3-C 6. All the patients underwent posterior cervical open-door laminoplasty, among whom 70 patients were treated via the intermuscular approach (intermuscular group) and 65 via the posterior midline approach (posterior midline group). The operation duration, intraoperative blood loss, postoperative drainage volume, and length of hospital stay were recorded. The visual analogue scale (VAS) score, Japanese Orthopedic Association (JOA) score, neck disability index (NDI), Barthel index, cervical Cobb angle, and cervical range of motion (ROM) were measured preoperatively, at 3, 6, 12 months postoperatively and at the final follow-up. The American Spinal Injury Association (ASIA) scale was evaluated preoperatively, at 3, 12 months postoperatively and at the final follow-up. The postoperative complication rate was recorded as well. Results:All the patients were followed up for 15-19 months [(16.3±1.6)months]. The operation duration, intraoperative blood loss, postoperative drainage and length of hospital stay were (125.0±23.0)minutes, (210.4±34.8)ml, and (165.3±23.7)ml, and (5.3±0.1)days in the intermuscular group, which were significantly shorter or less than (168.0±27.6)minutes, (260.2±45.3)ml, (196.4±31.6)ml, and (6.4±0.2)days in the posterior midline group ( P<0.01). The preoperative VAS score, JOA score, NDI and Barthel index showed no significant differences between the two groups ( P>0.05). The VAS score and JOA score also showed no significant differences between the two groups at 3, 6, 12 months postoperatively or at the final follow-up ( P>0.05). The NDI and Barthel index also showed no significant differences between the two groups at 3 months postoperatively ( P>0.05). At 6, 12 months postoperatively and at the final follow-up, the NDI were (15.4±2.5)points, (11.8±2.1)points and (8.6±1.5)points in the intermuscular group, significantly lower than (19.1±3.4)points, (14.3±2.4)points and (11.9±1.4)points in the posterior midline group ( P<0.01). At 6, 12 months postoperatively and at the final follow-up, the Barthel index were (71.4±6.2)points, (83.4±5.8)points and (89.2±7.1)points in the intermuscular group, significantly higher than (59.6±4.7)points, (74.2±3.9)points and (78.8±6.2)points in the posterior midline group ( P<0.01). Both groups showed significant improvements in VAS score, JOA score, NDI and Barthel index at 3, 6, 12 months postoperatively and at the final follow-up when compared to those preoperatively ( P<0.05). Among them, the VAS score, NDI and Barthel index were further improved over time ( P<0.05). Simultaneously, the JOA score was significantly improved at 6, 12 months postoperatively and at the last follow-up when compared to that at 3 months postoperatively ( P<0.05), with no significant difference at later time points between the two groups ( P>0.05). The preoperative cervical Cobb angle and ROM showed no significant differences between the two groups ( P>0.05). There was no significant difference in the Cobb angle between the two groups at 3, 6 or 12 months postoperatively ( P>0.05), while it was (13.6±2.4)° in the intermuscular group at the final follow-up, significantly larger than (10.4±2.8)° in the posterior midline group ( P<0.01). At 3, 6, 12 months postoperatively and at the final follow-up, the cervical ROM were (34.1±6.4)°, (32.6±7.3)°, (31.8±9.1)° and (29.6±8.7)° in the intermuscular group, significantly larger than (23.7±8.3)°, (22.3±7.8)°, (22.5±8.1)° and (20.6±9.3)° in the posterior midline group ( P<0.01). In the intermuscular group, the cervical Cobb angle showed no significant changes at 3, 6, 12 months postoperatively and at the final follow-up when compared to those preoperatively ( P>0.05). In the posterior midline group, the Cobb angles were significantly reduced at 3, 6, 12 months postoperatively and at the final follow-up when compared to those preoperatively ( P<0.05), showing significant decrease at 12 months postoperatively and at the final follow-up from those at 3, 6 months postoperatively ( P<0.05), no significant difference at 6 months postoperatively from that at 3 months postoperatively ( P>0.05), and significant decrease at the final follow-up from that at 12 months postoperatively ( P>0.05). In the intermuscular group, the cervical ROM were significantly improved at 3, 6, 12 months postoperatively and at the final follow-up when compared to those preoperatively and showed further improvement over time ( P<0.05). In the posterior midline group, the cervical ROM were significantly improved at 3, 6, 12 months postoperatively and at the final follow-up when compared to those preoperatively ( P<0.05), showing significant decreases at 6, 12 months postoperatively and at the final follow-up from that at 3 months postoperatively ( P<0.05), significant decreases at the final follow-up from those at 6, 12 months postoperatively ( P<0.05), and no significant difference at 12 months postoperatively from that at 6 months postoperatively ( P>0.05). The ASIA grades showed no significant difference between the two groups preoperatively, at 3, 12 months postoperatively and at the final follow-up ( P>0.05) , but were gradually improved over time in both groups ( P<0.05). The postoperative complication rate was 9%(6/70) in the intermuscular group, significantly lower than 48%(31/65) in the posterior midline group ( P<0.01). Conclusion:Compared to the posterior midline approach, the intermuscular approach for laminoplasty in patients with SCIWORA possesses advantages, including shorter operative time and length of hospital stay, reduced intraoperative blood loss and postoperative drainage, less postoperative neck disability, higher daily life quality, better long-term preservation of cervical lordosis and motion, and a lower complication rate.