Objective:To compare the efficacy of O-arm navigation-assisted and freehand posterior pedicle screw fixation in the treatment of ankylosing spondylitis (AS) associated with lower cervical fractures in adults.Methods:A retrospective cohort study was conducted to analyze the clinical data of 29 adult AS patients with lower cervical fractures admitted to Zhengzhou Orthopedic Hospital from June 2020 to September 2024, including 22 males and 7 females, aged 35-72 years [(52.3±11.1)years]. Injured segments involved C 5~6 in 6 patients, C 6 in 8, C 6~7 in 8, and C 7 in 7. Accirdubg to AO classification, the fracture was classified as type B3 in 22 patients and type C in 7. All the patients underwent posterior cervical pedicle screw fixation, among whom 15 patients were treated with navigation-assisted screw placement (navigation screw placement group, with 120 screws) and 14 with freehand technique (freehand screw placement group, with 112 screws). The two groups were compared in terms of the operative time, intraoperative blood loss, and postoperative drainage volume. The accuracy of screw placement, penetration rate of the pedicle cortex and fracture healing time were evaluated in the two groups. The Cobb angle before surgery and at 3 days after surgery and American Spinal Injury Association (ASIA) classification before surgery and at the last follow-up were recorded in the two groups. The visual analogue scale (VAS) score, Japanese Orthopedic Association (JOA) score and neck dysfunction index (NDI) before surgery, at 1 week, 3 months after surgery and at the last follow-up were compared between the two groups. The incidence of postoperative complications was also investigated. Results:All the patients were followed up for 6-57 months [(29.3±14.1)months]. The operation duration, intraoperative blood loss, and postoperative drainage volume were (166.0±31.4)minutes, (256.7±70.7)ml, and (91.0±14.4)ml in the navigation screw placement group, which were shorter or less than (219.29±31.7)minutes, (342.1±60.7)ml, and (123.2±20.7)ml in the freehand screw placement group ( P<0.01). The accuracy of screw placement in the navigation screw placement group was 98.3% (118/120) and penetration rate of the pedicle cortex was 5.8% (7/120), which were both superior to 89.3% (100/112) and 18.8% (21/112) in the freehand screw placement group ( P<0.01). No significant difference was detected in fracture healing time between the two groups ( P>0.05). There were no significant differences in the Cobb angle before surgery and at 3 days after surgery, as well as in the ASIA grading before surgery and at the last follow-up between the two groups ( P>0.05). The Cobb angle and ASIA classification at 3 days after surgery and at the last follow-up were improved compared with those before surgery ( P<0.05). Before surgery, at 1 week, 3 months after surgery, and at the last follow-up, the VAS scores were 8.0(7.0, 9.0)points, 4.0(3.0, 4.0)points, 2.0(1.0, 2.0)points, and 0.0(0.0, 1.0)points in the navigation screw placement group, which were not significantly different from 8.0(7.0, 9.0)points, 4.0(3.0, 4.0)points, 1.5(1.0, 2.0)points, and 0.0(0.0, 1.0)points in the freehand screw placement group ( P>0.05); the JOA scores were (7.5±1.4)points, (10.9±1.2)points, (13.2±1.5)points, and (15.7±1.0)points in the navigation screw placement group, which were not significantly different from (7.2±2.8)points, (10.1±3.2)points, (11.8±3.8)points, and (14.1±4.3)points in the freehand screw placement group ( P>0.05); the NDI were 48.0(44.0, 56.0)%, 30.0(30.0, 34.0)%, 18.0(16.0, 22.0)%, 8.0(6.0, 10.0)% in the navigation screw placement group, which were not significantly different from 44.0(40.0, 52.0)%, 30.0(29.0, 34.5)%, 17.0(16.0, 20.0)%, and 8.0(5.5, 10.0)% in the freehand screw placement group ( P>0.05). The VAS scores, JOA scores, and NDI were improved at 1 week, 3 months after surgery, and at the last follow-up in both groups, compared to those before surgery and they were gradually improved with the passage of the follow-up time ( P<0.05). One patient in the navigation screw placement group developed postoperative pulmonary infection and recovered after symptomatic treatment, with an incidence of complications 7% (1/15). Two patients in the freehand screw placement group had postoperative cerebrospinal fluid leakage and dural rupture and recovered after symptomatic treatment, with an incidence of complications 14% (2/14). Throughout the follow-up period, no complications such as screw breakage, implant loosening, or loss of correction were found in either group. Conclusion:Compared with freehand screw placement, the O-arm navigation system-assisted posterior pedicle screw fixation in the treatment of AS associated with lower cervical fractures in adults demonstrates significant advantages, including reduced operative time, decreased intraoperative blood loss and postoperative drainage volume, improved accuracy of screw placement, and reduced penetration rate of the pedicle cortex.

Objective:To compare the efficacy of whole-process visualization system-assisted pedicle screw internal fixation and free-hand pedicle screw internal fixation in the treatment of thoracolumbar burst fracture (TLBF) without neurologic symptoms.Methods:A retrospective cohort study was conducted to analyze the clinical data of 64 patients with TLBF without neurologic symptoms admitted to Zhengzhou Orthopedic Hospital from December 2020 to October 2022, including 41 males and 23 females, aged 23-52 years [(42.1±6.6)years]. The injured vertebrae involved T 11 in 26 patients, T 12 in 17, L 1 in 12, and L 2 in 9. The Wiltse approach was used in all the patients, 31 of whom were treated with pedicle screw internal fixation assisted by the whole-process visualization system (visualization system-assisted screw placement group) and 33 of whom were treated with free-hand pedicle screw internal fixation (free-hand screw placement group). The two groups were compared in terms of operation time, single screw placement time, intraoperative blood loss, intraoperative total radiation dose and total length of hospital stay. The accuracy of pedicle screw placement and penetration rate of the pedicle cortex were evaluated in the two groups. The Cobb angle and lumbar visual analogue scale (VAS) before surgery, at 1 week, 3 months after surgery and at the last follow-up were compared between the two groups. The incidence of postoperative complications was also investigated. Results:All the patients were followed up for 10-33 months [(17.5±4.8)months]. The operation time was (106.9±11.8)minutes in the visualization system-assisted screw placement group, shorter than (121.3±11.4)minutes in the free-hand screw placement group ( P<0.01). The single screw placement time was (9.1±1.0)minutes in the visualization system-assisted screw placement group, shorter than (11.7±1.5)minutes in the free-hand screw placement group ( P<0.01). The total radiation dose was (10.4±2.4)mGy in the visualization system-assisted screw placement group, lower than (51.8±7.2)mGy in the screw placement group ( P<0.01). There was no significant difference in intraoperative blood loss or total length of hospital stay between the two groups ( P>0.05). The accuracy of pedicle screw placement was 96.6% (197/204) in the visualization system-assisted screw placement group, significantly higher than 89.3% (191/214) in the free-hand screw placement group ( P<0.01). Both groups showed significant improvements in Cobb angle and VAS scores at 1 week, 3 months after surgery, and at the last follow-up ( P<0.05). There were no significant differences in Cobb angle or VAS scores between the two groups at each time point ( P>0.05). In the visualization system-assisted screw placement group, one patient had incision infection at 4 days after operation, which was cured with antibiotics. One patient in the free-hand screw placement group developed the symptoms of nerve root irritation at 2 days after surgery, which disappeared at 7 days after revision. There was no significant difference in the incidence of complications between the two groups ( P>0.05). During the follow-up, no patients had broken screws, loosening of internal fixation, or loss of correction in either group. Conclusions:Compared with free-hand pedicle screw internal fixation, the whole-process visualization system-assisted pedicle screw internal fixation in the treatment of TLBF without neurologic symptoms can shorten the time of operation and screw placement, reduce the radiation dose, and improve the accuracy of pedicle screw placement, suggesting that it is a safer and more effective auxiliary method for pedicle screw placement.

Background:To compare the efficacy and safety of monthly administrations of gonadotropin releasing hormone (GnRH) agonists LY01005 and Zoladex ? in Chinese patients with premenopausal breast cancer. Methods:From October 2020 to November 2021, 188 premenopausal breast cancer patients were enrolled in 34 hospitals and randomized 1:1 to receive either LY01005 or Zoladex ? every 28 days for a total of three injections. All patients concomitantly received oral tamoxifen (TAM). The primary efficacy endpoint was cumulative probability of maintaining menopausal level [oestradiol (E2) ≤30 pg/ml] from day 29 to day 85. The second efficacy endpoint included changes in E2, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) compared with the baseline. Pharmacokinetics (PK), pharmacodynamics (PD), and safety were analyzed. The study also evaluated the pharmacokinetic and pharmacodynamic characteristics of LY01005. Results:A total of 188 patients were randomised and 187 patients received either LY01005 or Zoladex ?. Cumulative probabilities of maintaining menopausal level (E2≤30 pg/ml) from day 29 to day 85 were 93.1% for LY01005 and 86.3% for Zoladex ?. The between-group difference was 6.8% (95% CI: -2.3%, 15.9%) and primary efficacy in the LY01005 group was not inferior to that in the Zoladex ? group. Changes in E2, LH, and FSH levels compared with the baseline were equivalent between the two groups (E2: 89.34% to 90.23% vs. 82.11% to 85.02%; LH: 88.89% to 95.52% vs. 89.70% to 97.02%; FSH: 75.36% to 80.85% vs.73.07% to 80.24%, respectively). After three consecutive doses of LY01005, the LH and FSH levels of the subjects showed a transient increase after the first dose, reached a peak on the second day and then started to decrease. The LH and FSH reached a lower level and remained at or below that level until the 85th day. Both treatments were well-tolerated. Conclusion:LY01005 is as effective as Zoladex ? in suppressing E2 to menopausal levels in Chinese patients with premenopausal breast cancer, with a similar safety profile.

BACKGROUND:In the repair of large bone defects,a variety of factors such as seed cell passaging can cause senescence of osteoblasts,leading to a reduction in osteogenic differentiation activity after implantation of tissue-engineered bone.In recent years,a novel mechanism involving primary cilia in cell senescence has been widely studied,but the primary cilia-related mechanism of"passage senescence-reduced osteogenic activity"is not fully understood.OBJECTIVE:To explore the possible mechanisms by which primary cilia regulate the senescence of MC3T3-E1 cells.METHODS:The osteoblast precursor cell lines MC3T3-E1 were passaged to 10th generation cells(early passage)and 40th generation cells(late passage).siRNA was used to silence IFT88 to inhibit primary cilia formation.The cells were than grouped into passage 10 group,passage 40 group,passage 10+siRNA IFT88 group,and passage 40+siRNA IFT88 group.RT-PCR and western blot assays were used to detect the expression of the aging marker P16(CDKN2A),the osteogenic activity markers bone morphogenetic protein 2 and alkaline phosphatase,and the Hedgehog pathway IHH expression.Alizarin red staining and primary cilia immunofluorescence staining were performed.Spearman correlation analysis was conducted to analyze primary cilia positive rate and IHH and bone morphogenetic protein 2 expression.RESULTS AND CONCLUSION:(1)The expression of CDKN2A(P16)in the passage 10 group was significantly higher than in the passage 40 group,but the difference disappeared after siRNA IFT88 intervention.(2)Meanwhile,the positive rate of primary cilia cells in the passage 10 group were higher than in the passage 40 group,while siRNA IFT88-significantly inhibited the expression of primary cilia in both passage 10 and passage 40 cells.(3)The transcriptional activity and protein expression of bone morphogenetic protein 2 and alkaline phosphatase in the passage 10 group were higher than those in the passage 40 group.After inhibiting the expression of primary cilia with siRNA,the above differences were reduced or disappeared.(4)The positive rate of primary cilia cells was correlated with IHH and bone morphogenetic protein 2 protein expression.To conclude,primary cilia mediate the replicative senescence of osteogenic MC3T3-E1 cells and regulate osteogenic differentiation ability.

BACKGROUND:In the repair of large bone defects,a variety of factors such as seed cell passaging can cause senescence of osteoblasts,leading to a reduction in osteogenic differentiation activity after implantation of tissue-engineered bone.In recent years,a novel mechanism involving primary cilia in cell senescence has been widely studied,but the primary cilia-related mechanism of"passage senescence-reduced osteogenic activity"is not fully understood.OBJECTIVE:To explore the possible mechanisms by which primary cilia regulate the senescence of MC3T3-E1 cells.METHODS:The osteoblast precursor cell lines MC3T3-E1 were passaged to 10th generation cells(early passage)and 40th generation cells(late passage).siRNA was used to silence IFT88 to inhibit primary cilia formation.The cells were than grouped into passage 10 group,passage 40 group,passage 10+siRNA IFT88 group,and passage 40+siRNA IFT88 group.RT-PCR and western blot assays were used to detect the expression of the aging marker P16(CDKN2A),the osteogenic activity markers bone morphogenetic protein 2 and alkaline phosphatase,and the Hedgehog pathway IHH expression.Alizarin red staining and primary cilia immunofluorescence staining were performed.Spearman correlation analysis was conducted to analyze primary cilia positive rate and IHH and bone morphogenetic protein 2 expression.RESULTS AND CONCLUSION:(1)The expression of CDKN2A(P16)in the passage 10 group was significantly higher than in the passage 40 group,but the difference disappeared after siRNA IFT88 intervention.(2)Meanwhile,the positive rate of primary cilia cells in the passage 10 group were higher than in the passage 40 group,while siRNA IFT88-significantly inhibited the expression of primary cilia in both passage 10 and passage 40 cells.(3)The transcriptional activity and protein expression of bone morphogenetic protein 2 and alkaline phosphatase in the passage 10 group were higher than those in the passage 40 group.After inhibiting the expression of primary cilia with siRNA,the above differences were reduced or disappeared.(4)The positive rate of primary cilia cells was correlated with IHH and bone morphogenetic protein 2 protein expression.To conclude,primary cilia mediate the replicative senescence of osteogenic MC3T3-E1 cells and regulate osteogenic differentiation ability.

Objective:To compare the efficacy of O-arm navigation-assisted and freehand posterior pedicle screw fixation in the treatment of ankylosing spondylitis (AS) associated with lower cervical fractures in adults.Methods:A retrospective cohort study was conducted to analyze the clinical data of 29 adult AS patients with lower cervical fractures admitted to Zhengzhou Orthopedic Hospital from June 2020 to September 2024, including 22 males and 7 females, aged 35-72 years [(52.3±11.1)years]. Injured segments involved C 5~6 in 6 patients, C 6 in 8, C 6~7 in 8, and C 7 in 7. Accirdubg to AO classification, the fracture was classified as type B3 in 22 patients and type C in 7. All the patients underwent posterior cervical pedicle screw fixation, among whom 15 patients were treated with navigation-assisted screw placement (navigation screw placement group, with 120 screws) and 14 with freehand technique (freehand screw placement group, with 112 screws). The two groups were compared in terms of the operative time, intraoperative blood loss, and postoperative drainage volume. The accuracy of screw placement, penetration rate of the pedicle cortex and fracture healing time were evaluated in the two groups. The Cobb angle before surgery and at 3 days after surgery and American Spinal Injury Association (ASIA) classification before surgery and at the last follow-up were recorded in the two groups. The visual analogue scale (VAS) score, Japanese Orthopedic Association (JOA) score and neck dysfunction index (NDI) before surgery, at 1 week, 3 months after surgery and at the last follow-up were compared between the two groups. The incidence of postoperative complications was also investigated. Results:All the patients were followed up for 6-57 months [(29.3±14.1)months]. The operation duration, intraoperative blood loss, and postoperative drainage volume were (166.0±31.4)minutes, (256.7±70.7)ml, and (91.0±14.4)ml in the navigation screw placement group, which were shorter or less than (219.29±31.7)minutes, (342.1±60.7)ml, and (123.2±20.7)ml in the freehand screw placement group ( P<0.01). The accuracy of screw placement in the navigation screw placement group was 98.3% (118/120) and penetration rate of the pedicle cortex was 5.8% (7/120), which were both superior to 89.3% (100/112) and 18.8% (21/112) in the freehand screw placement group ( P<0.01). No significant difference was detected in fracture healing time between the two groups ( P>0.05). There were no significant differences in the Cobb angle before surgery and at 3 days after surgery, as well as in the ASIA grading before surgery and at the last follow-up between the two groups ( P>0.05). The Cobb angle and ASIA classification at 3 days after surgery and at the last follow-up were improved compared with those before surgery ( P<0.05). Before surgery, at 1 week, 3 months after surgery, and at the last follow-up, the VAS scores were 8.0(7.0, 9.0)points, 4.0(3.0, 4.0)points, 2.0(1.0, 2.0)points, and 0.0(0.0, 1.0)points in the navigation screw placement group, which were not significantly different from 8.0(7.0, 9.0)points, 4.0(3.0, 4.0)points, 1.5(1.0, 2.0)points, and 0.0(0.0, 1.0)points in the freehand screw placement group ( P>0.05); the JOA scores were (7.5±1.4)points, (10.9±1.2)points, (13.2±1.5)points, and (15.7±1.0)points in the navigation screw placement group, which were not significantly different from (7.2±2.8)points, (10.1±3.2)points, (11.8±3.8)points, and (14.1±4.3)points in the freehand screw placement group ( P>0.05); the NDI were 48.0(44.0, 56.0)%, 30.0(30.0, 34.0)%, 18.0(16.0, 22.0)%, 8.0(6.0, 10.0)% in the navigation screw placement group, which were not significantly different from 44.0(40.0, 52.0)%, 30.0(29.0, 34.5)%, 17.0(16.0, 20.0)%, and 8.0(5.5, 10.0)% in the freehand screw placement group ( P>0.05). The VAS scores, JOA scores, and NDI were improved at 1 week, 3 months after surgery, and at the last follow-up in both groups, compared to those before surgery and they were gradually improved with the passage of the follow-up time ( P<0.05). One patient in the navigation screw placement group developed postoperative pulmonary infection and recovered after symptomatic treatment, with an incidence of complications 7% (1/15). Two patients in the freehand screw placement group had postoperative cerebrospinal fluid leakage and dural rupture and recovered after symptomatic treatment, with an incidence of complications 14% (2/14). Throughout the follow-up period, no complications such as screw breakage, implant loosening, or loss of correction were found in either group. Conclusion:Compared with freehand screw placement, the O-arm navigation system-assisted posterior pedicle screw fixation in the treatment of AS associated with lower cervical fractures in adults demonstrates significant advantages, including reduced operative time, decreased intraoperative blood loss and postoperative drainage volume, improved accuracy of screw placement, and reduced penetration rate of the pedicle cortex.

Objective:To compare the efficacy of whole-process visualization system-assisted pedicle screw internal fixation and free-hand pedicle screw internal fixation in the treatment of thoracolumbar burst fracture (TLBF) without neurologic symptoms.Methods:A retrospective cohort study was conducted to analyze the clinical data of 64 patients with TLBF without neurologic symptoms admitted to Zhengzhou Orthopedic Hospital from December 2020 to October 2022, including 41 males and 23 females, aged 23-52 years [(42.1±6.6)years]. The injured vertebrae involved T 11 in 26 patients, T 12 in 17, L 1 in 12, and L 2 in 9. The Wiltse approach was used in all the patients, 31 of whom were treated with pedicle screw internal fixation assisted by the whole-process visualization system (visualization system-assisted screw placement group) and 33 of whom were treated with free-hand pedicle screw internal fixation (free-hand screw placement group). The two groups were compared in terms of operation time, single screw placement time, intraoperative blood loss, intraoperative total radiation dose and total length of hospital stay. The accuracy of pedicle screw placement and penetration rate of the pedicle cortex were evaluated in the two groups. The Cobb angle and lumbar visual analogue scale (VAS) before surgery, at 1 week, 3 months after surgery and at the last follow-up were compared between the two groups. The incidence of postoperative complications was also investigated. Results:All the patients were followed up for 10-33 months [(17.5±4.8)months]. The operation time was (106.9±11.8)minutes in the visualization system-assisted screw placement group, shorter than (121.3±11.4)minutes in the free-hand screw placement group ( P<0.01). The single screw placement time was (9.1±1.0)minutes in the visualization system-assisted screw placement group, shorter than (11.7±1.5)minutes in the free-hand screw placement group ( P<0.01). The total radiation dose was (10.4±2.4)mGy in the visualization system-assisted screw placement group, lower than (51.8±7.2)mGy in the screw placement group ( P<0.01). There was no significant difference in intraoperative blood loss or total length of hospital stay between the two groups ( P>0.05). The accuracy of pedicle screw placement was 96.6% (197/204) in the visualization system-assisted screw placement group, significantly higher than 89.3% (191/214) in the free-hand screw placement group ( P<0.01). Both groups showed significant improvements in Cobb angle and VAS scores at 1 week, 3 months after surgery, and at the last follow-up ( P<0.05). There were no significant differences in Cobb angle or VAS scores between the two groups at each time point ( P>0.05). In the visualization system-assisted screw placement group, one patient had incision infection at 4 days after operation, which was cured with antibiotics. One patient in the free-hand screw placement group developed the symptoms of nerve root irritation at 2 days after surgery, which disappeared at 7 days after revision. There was no significant difference in the incidence of complications between the two groups ( P>0.05). During the follow-up, no patients had broken screws, loosening of internal fixation, or loss of correction in either group. Conclusions:Compared with free-hand pedicle screw internal fixation, the whole-process visualization system-assisted pedicle screw internal fixation in the treatment of TLBF without neurologic symptoms can shorten the time of operation and screw placement, reduce the radiation dose, and improve the accuracy of pedicle screw placement, suggesting that it is a safer and more effective auxiliary method for pedicle screw placement.

Background:To compare the efficacy and safety of monthly administrations of gonadotropin releasing hormone (GnRH) agonists LY01005 and Zoladex ? in Chinese patients with premenopausal breast cancer. Methods:From October 2020 to November 2021, 188 premenopausal breast cancer patients were enrolled in 34 hospitals and randomized 1:1 to receive either LY01005 or Zoladex ? every 28 days for a total of three injections. All patients concomitantly received oral tamoxifen (TAM). The primary efficacy endpoint was cumulative probability of maintaining menopausal level [oestradiol (E2) ≤30 pg/ml] from day 29 to day 85. The second efficacy endpoint included changes in E2, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) compared with the baseline. Pharmacokinetics (PK), pharmacodynamics (PD), and safety were analyzed. The study also evaluated the pharmacokinetic and pharmacodynamic characteristics of LY01005. Results:A total of 188 patients were randomised and 187 patients received either LY01005 or Zoladex ?. Cumulative probabilities of maintaining menopausal level (E2≤30 pg/ml) from day 29 to day 85 were 93.1% for LY01005 and 86.3% for Zoladex ?. The between-group difference was 6.8% (95% CI: -2.3%, 15.9%) and primary efficacy in the LY01005 group was not inferior to that in the Zoladex ? group. Changes in E2, LH, and FSH levels compared with the baseline were equivalent between the two groups (E2: 89.34% to 90.23% vs. 82.11% to 85.02%; LH: 88.89% to 95.52% vs. 89.70% to 97.02%; FSH: 75.36% to 80.85% vs.73.07% to 80.24%, respectively). After three consecutive doses of LY01005, the LH and FSH levels of the subjects showed a transient increase after the first dose, reached a peak on the second day and then started to decrease. The LH and FSH reached a lower level and remained at or below that level until the 85th day. Both treatments were well-tolerated. Conclusion:LY01005 is as effective as Zoladex ? in suppressing E2 to menopausal levels in Chinese patients with premenopausal breast cancer, with a similar safety profile.

Objective:To explore the efficacy of stage I modified posterior vertebral column resection (mPVCR) in the treatment of postoperative infection after percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fracture (OVCF).Methods:A retrospective case series study was conducted to analyze the clinical data of 11 OVCF patients with post-PVP infection who were admitted to Zhengzhou Orthopedics Hospital from January 2016 to June 2022, including 4 males and 7 females, aged 61-81 years [(70.2±6.4)years]. Injured segments included T 9 in 1 patient, T 11 in 2, T 12 in 3, L 1 in 1, L 2 in 2, T 11-T 12 in 1, and T 12-L 1 in 1. American Spinal Injury Association (ASIA) grading was grade D in 5 patients and grade E in 6. All the patients were treated with stage I mPVCR. The operation time and intraoperative bleeding volume were recorded. The values of Visual Analogue Scale (VAS), Oswestry Dysfunction Index (ODI), and Cobb angle of the lesion segments before, at 2 weeks, 3 months after surgery, and at the last follow-up were compared. The loss of Cobb angle of the lesion segments at 2 weeks after surgery and at the last follow-up were compared, and the ASIA grading at the last follow-up was recorded. The infection control, bone healing, and the incidence of complications were observed at the last follow-up. Results:All the patients were followed up for 12-44 months [(26.0±9.4)months]. The operation time and intraoperative bleeding volume were 230-330 minutes [(279.2±28.6)minutes] and 500-1 100 ml [(840.9±184.1)ml] respectively. At 2 weeks, 3 months after surgery and at the last follow-up, the VAS scores were (4.0±0.8)points, (2.7±0.9)points, and (2.4±0.7)points respectively, which were all lower than that before surgery [(8.1±1.2)points] ( P<0.01); the ODI was (45.5±5.1)%, (30.0±6.5)%, and (18.5±3.6)% respectively, which were all lower than that before surgery [(78.7±6.2)%] ( P<0.01); the Cobb angle of the lesion segments were (7.9±1.4)°, (8.5±1.4)°, and (9.2±1.5)° respectively, which were lower than that before surgery [(25.5±9.2)°] ( P<0.01). The VAS and ODI were both improved at 3 months after surgery compared with those at 2 weeks after surgery ( P<0.05), while there was no significant difference in Cobb angle of the lesion segments ( P>0.05). The ODI was further improved at the last follow-up compared with that at 3 months after surgery ( P<0.05), while there were no significant differences in VAS or Cobb angle of the lesion segments ( P>0.05). The loss of Cobb angle correction of the lesion segment at the last follow-up was 0.96 (0.69, 1.45)° compared with that at 2 weeks after surgery and the rate of loss of Cobb angle correction of the lesion segment was 4.4(2.2, 7.4)%. At the last follow-up, the ASIA grading was grade E for all the patients, who were able to walk normally independently. The infection was all cured and good bony fusion was observed in the operated area at the last follow-up. Two patients had pleural effusion and pulmonary atelectasis, 1 incision fat liquefaction, and 1 pneumonia after the surgery. None of the patients had internal fixation failure and serious complications such as worsening neurological symptoms or death. Conclusion:Stage I mPVCR for the treatment of post-PVP infection in patients with OVCF is proved to attain significant pain relief and functional improvement, good correction results, effective reconstruction of spinal stability, complete removal of infected lesions, and few serious complications.

Objective:To investigate the efficacy of one-stage posterior-anterior combined operation for the treatment of abnormal fusion after facet joint dislocation in the subaxial cervical spine.Methods:A retrospective study of case series was conducted to analyze the clinical data of 10 patients with abnormal fusion after facet joint dislocation in the subaxial cervical spine who had been admitted to Department of Spine Surgery, Zhengzhou Orthopedic Hospital from January 2015 to May 2023. There were 7 males and 3 females with an age of (41.2±3.1) years. Preoperative American Spinal Injury Association (ASIA) grading: 5 cases of grade A, 4 cases of grade B, and 1 cases of grade C. All the patients were treated with one-stage posterior-anterior combined operation. The surgical time and intraoperative bleeding volume were recorded. The ASIA grading was used to evaluate the improvements in nerve function of the spinal cord 3 months after surgery. The VAS scores, cervical intervertebral heights, and Cobb angles were compared between pre-surgery, 3 months after surgery, and the last follow-up. The fusion of intervertebral bone graft was evaluated 3 months after surgery using the Bridgell intervertebral fusion criteria. Complications were observed.Results:All patients were followed up for 15.5 (13.8, 20.5) months. The surgical time was (119.5±3.6) minutes, and the intraoperative bleeding volume (141.6±25.6) mL. Significant improvements in VAS score, cervical intervertebral height, and Cobb angle were observed at 3 months after surgery and the last follow-up compared with the pre-surgery values ( P<0.05), but there was no statistically significant difference between 3 months after surgery and the last follow-up ( P>0.05). ASIA grading 3 months after surgery: 4 cases of grade A, 4 cases of grade B, and 2 cases of grade C. By the Bridgell intervertebral fusion criteria at 3 months after surgery: 9 cases of grade Ⅰ and 1 cases of grade Ⅱ, showing good intervertebral fusion. Surgery went on well for all patients, showing no postoperative complications such as aggravation of nerve lesion or vascular injury. Conclusion:In the treatment of abnormal fusion after facet joint dislocation in the subaxial cervical spine, the efficacy of one-stage posterior-anterior combined operation is definite because it can effectively reduce pain, restore the height and physiological curvature of the cervical intervertebral space, and achieve good intervertebral fusion.