Humans ; Osteoblastoma/surgery* ; Neck/surgery* ; Spinal Neoplasms ; Cervical Vertebrae

To investigate the effects of postoperative fusion implantation on the mesoscopic biomechanical properties of vertebrae and bone tissue osteogenesis in idiopathic scoliosis, a macroscopic finite element model of the postoperative fusion device was developed, and a mesoscopic model of the bone unit was developed using the Saint Venant sub-model approach. To simulate human physiological conditions, the differences in biomechanical properties between macroscopic cortical bone and mesoscopic bone units under the same boundary conditions were studied, and the effects of fusion implantation on bone tissue growth at the mesoscopic scale were analyzed. The results showed that the stresses in the mesoscopic structure of the lumbar spine increased compared to the macroscopic structure, and the mesoscopic stress in this case is 2.606 to 5.958 times of the macroscopic stress; the stresses in the upper bone unit of the fusion device were greater than those in the lower part; the average stresses in the upper vertebral body end surfaces were ranked in the order of right, left, posterior and anterior; the stresses in the lower vertebral body were ranked in the order of left, posterior, right and anterior; and rotation was the condition with the greatest stress value in the bone unit. It is hypothesized that bone tissue osteogenesis is better on the upper face of the fusion than on the lower face, and that bone tissue growth rate on the upper face is in the order of right, left, posterior, and anterior; while on the lower face, it is in the order of left, posterior, right, and anterior; and that patients' constant rotational movements after surgery is conducive to bone growth. The results of the study may provide a theoretical basis for the design of surgical protocols and optimization of fusion devices for idiopathic scoliosis.
Humans ; Scoliosis/surgery* ; Spinal Fusion/methods* ; Lumbar Vertebrae/surgery* ; Osteogenesis ; Biomechanical Phenomena/physiology* ; Finite Element Analysis

OBJECTIVE: To introduce a scout view scanning technique of back-forward bending CT (BFB-CT) in simulated surgical position for evaluating the remaining real angle and flexibility of thoracolumbar kyphosis secondary to old osteoporotic vertebral compression fracture. METHODS: A total of 28 patients with thoracolumbar kyphosis secondary to old osteoporotic vertebral compression fracture who met the selection criteria between June 2018 and December 2021 were included in the study. There were 6 males and 22 females with an average age of 69.5 years (range, 56-92 years). The injured vertebra were located at T ₁₀-L ₂, including 11 cases of single thoracic fracture, 11 cases of single lumbar fracture, and 6 cases of multiple thoracolumbar fractures. The disease duration ranged from 3 weeks to 36 months, with a median of 5 months. All patients received examinations of BFB-CT and standing lateral full-spine X-ray (SLFSX). The thoracic kyphosis (TK), thoracolumbar kyphosis (TLK), local kyphosis of injured vertebra (LKIV), lumbar lordosis (LL), and the sagittal vertical axis (SVA) were measured. Referring to the calculation method of scoliosis flexibility, the kyphosis flexibility of thoracic, thoracolumbar, and injured vertebra were calculated respectively. The sagittal parameters measured by the two methods were compared, and the correlation of the parameters measured by the two methods was analyzed by Pearson correlation. RESULTS: Except LL ( P>0.05), TK, TLK, LKIV, and SVA measured by BFB-CT were significantly lower than those measured by SLFSX ( P<0.05). The flexibilities of thoracic, thoracolumbar, and injured vertebra were 34.1%±18.8%, 36.2%±13.8%, and 39.3%±18.6%, respectively. Correlation analysis showed that the sagittal parameters measured by the two methods were positively correlated ( P<0.001), and the correlation coefficients of TK, TLK, LKIV, and SVA were 0.900, 0.730, 0.700, and 0.680, respectively. CONCLUSION Thoracolumbar kyphosis secondary to old osteoporotic vertebral compression fracture shows an excellent flexibility and BFB-CT in simulated surgical position can obtain the remaining real angle which need to be corrected surgically.
Male ; Female ; Humans ; Aged ; Fractures, Compression/surgery* ; Spinal Fractures/diagnostic imaging* ; Lumbar Vertebrae/surgery* ; Thoracic Vertebrae/surgery* ; Kyphosis/surgery* ; Osteoporotic Fractures/surgery* ; Lordosis ; Tomography, X-Ray Computed ; Retrospective Studies

OBJECTIVE: To establish the mode of anterior cervical surgery in outpatient setting, and evaluate its preliminary effectiveness. METHODS: A clinical data of patients who underwent anterior cervical surgery between January 2022 and September 2022 and met the selection criteria was retrospectively analyzed. The surgeries were performed in outpatient setting ( n=35, outpatient setting group) or in inpatient setting ( n=35, inpatient setting group). There was no significant difference between the two groups ( P>0.05) in age, gender, body mass index, smoking, history of alcohol drinking, disease type, the number of surgical levels, operation mode, as well as preoperative Japanese Orthopaedic Association (JOA) score, visual analogue scale score of neck pain (VAS-neck), and visual analogue scale score of upper limb pain (VAS-arm). The operation time, intraoperative blood loss, total hospital stay, postoperative hospital stay, and hospital expenses of the two groups were recorded; JOA score, VAS-neck score, and VAS-arm score were recorded before and immediately after operation, and the differences of the above indexes between pre- and post-operation were calculated. Before discharge, the patient was asked to score satisfaction with a score of 1-10. RESULTS: The total hospital stay, postoperative hospital stay, and hospital expenses were significantly lower in the outpatient setting group than in the inpatient setting group ( P<0.05). The satisfaction of patients was significantly higher in the outpatient setting group than in the inpatient setting group ( P<0.05). There was no significant difference between the two groups in operation time and intraoperative blood loss ( P>0.05). The JOA score, VAS-neck score, and VAS-arm score of the two groups significantly improved at immediate after operation when compared with those before operation ( P<0.05). There was no significant difference in the improvement of the above scores between the two groups ( P>0.05). The patients were followed up (6.67±1.04) months in the outpatient setting group and (5.95±1.90) months in the inpatient setting group, with no significant difference ( t=0.089, P=0.929). No surgical complications, such as delayed hematoma, delayed infection, delayed neurological damage, and esophageal fistula, occurred in the two groups. CONCLUSION The safety and efficiency of anterior cervical surgery performed in outpatient setting were comparable to that performed in inpatient setting. Outpatient surgery mode can significantly shorten the postoperative hospital stay, reduce hospital expenses, and improve the patients' medical experience. The key points of the outpatient mode of anterior cervical surgery are minimizing damage, complete hemostasis, no drainage placement, and fine perioperative management.
Humans ; Treatment Outcome ; Cervical Vertebrae/surgery* ; Outpatients ; Retrospective Studies ; Blood Loss, Surgical ; Spinal Fusion ; Neck Pain

OBJECTIVE: To investigate the feasibility of predicting proximal junctional kyphosis (PJK) in adults after spinal deformity surgery based on back-forward Bending CT localization images and related predictive indicators. METHODS: A retrospective analysis was performed for 31 adult patients with spinal deformity who underwent posterior osteotomy and long-segment fusion fixation between March 2017 and March 2020. There were 5 males and 26 females with an average age of 62.5 years (range, 30-77 years). The upper instrumented vertebrae (UIV) located at T ₅ in 1 case, T ₆ in 1 case, T ₉ in 13 cases, T ₁₀ in 12 cases, and T ₁₁ in 4 cases. The lowest instrumented vertebrae (LIV) located at L ₁ in 3 cases, L ₂ in 3 cases, L ₃ in 10 cases, L ₄ in 7 cases, L ₅ in 5 cases, and S ₁ in 3 cases. Based on the full-length lateral X-ray film of the spine in the standing position before and after operation and back-forward Bending CT localization images before operation, the sagittal sequence of the spine was obtained, and the relevant indexes were measured, including thoracic kyphosis (TK), lumbar lordosis (LL), local kyphosis Cobb angle (LKCA) [the difference between the different positions before operation (recovery value) was calculated], kyphosis flexibility, hyperextension sagittal vertical axis (hSVA), T ₂-L ₅ hyperextension C ₇-vertebral sagittal offset (hC ₇-VSO), and pre- and post-operative proximal junctional angle (PJA). At last follow-up, the patients were divided into PJK and non-PJK groups based on PJA to determine whether they had PJK. The gender, age, body mass index (BMI), number of fusion segments, number of cases with coronal plane deformity, bone mineral density (T value), UIV position, LIV position, operation time, intraoperative blood loss, osteotomy grading, and related imaging indicators were compared between the two groups. The hC ₇-VSO of the vertebral body with significant differences between groups was taken, and the receiver operating characteristic curve (ROC) was used to evaluate its accuracy in predicting the occurrence of PJK. RESULTS: All 31 patients were followed up 13-52 months, with an average of 30.0 months. The patient's PJA was 1.4°-29.0° at last follow-up, with an average of 10.4°; PJK occurred in 8 cases (25.8%). There was no significant difference in gender, age, BMI, number of fusion segments, number of cases with coronal plane deformity, bone mineral density (T value), UIV position, LIV position, operation time, intraoperative blood loss, and osteotomy grading between the two groups ( P>0.05). Imaging measurements showed that the LL recovery value and T ₈-L ₃ vertebral hC ₇-VSO in the PJK group were significantly higher than those in the non-PJK group ( P>0.05). There was no significant difference in hyperextension TK, hyperextension LL, hyperextension LKCA, TK recovery value, LL recovery value, kyphosis flexibility, hSVA, and T ₂-T ₇, L ₄, L ₅ vertebral hC ₇-VSO ( P>0.05). T ₈-L ₃ vertebral hC ₇-VSO was analyzed for ROC curve, and combined with the area under curve and the comprehensive evaluation of sensitivity and specificity, the best predictive index was hC ₇-L ₂, the cut-off value was 2.54 cm, the sensitivity was 100%, and the specificity was 60.9%. CONCLUSION Preoperative back-forward Bending CT localization image can be used to predict the occurrence of PJK after posterior osteotomy and long-segment fusion fixation in adult spinal deformity. If the patient's T ₈-L ₂ vertebral hC ₇-VSO is too large, it indicates a higher risk of postoperative PJK. The best predictive index is hC ₇-L ₂, and the cut-off value is 2.54 cm.
Male ; Female ; Humans ; Adult ; Middle Aged ; Retrospective Studies ; Blood Loss, Surgical ; Thoracic Vertebrae/surgery* ; Kyphosis/surgery* ; Lordosis/surgery* ; Spinal Fusion/methods* ; Tomography, X-Ray Computed ; Postoperative Complications/diagnostic imaging* ; Lumbar Vertebrae/surgery*

OBJECTIVE: To investigate the changes in spinal-pelvic sagittal parameters from preoperative standing to prone position in old traumatic spinal fractures with kyphosis. METHODS: The clinical data of 36 patients admitted between December 2016 and June 2021 for surgical treatment of old traumatic spinal fractures with kyphosis, including 7 males and 29 females, aged from 50 to 79 years (mean, 63.9 years), were retrospectively analyzed. Lesion segments included 2 cases of T ₁₁, 12 cases of T ₁₂, 2 cases of T _{11, 12}, 4 cases of T ₁₂ and L ₁, 12 cases of L ₁, 2 cases of L ₂, 1 case of L _{2, 3}, and 1 case of L ₃. The disease duration ranged from 4 to 120 months, with an average of 19.6 months. Surgical procedures included Smith-Petersen osteotomy in 4 cases, Ponte osteotomy in 6 cases, pedicle subtraction osteotomy in 2 cases, and improved fourth level osteotomy in 18 cases; the remaining 6 cases were not osteotomized. The bone mineral density ranged from -3.0 to 0.5 T, with a mean of -1.62 T. The spinal-pelvic sagittal parameters from preoperative standing to prone positions were measured, including local kyphosis Cobb angle (LKCA), thoracic kyphosis (TK), lumbar lordosis (LL), sacral slope (SS), pelvic tilt (PT), and PI and LL mismatch (PI-LL). The kyphotic flexibility=(preoperative standing LKCA-preoperative prone LKCA)/preoperative standing LKCA×100%. Spinal-pelvic sagittal parameters were compared between standing position and prone position before operation, and Pearson correlation was used to judge the correlation between the parameters of standing position and prone position before operation. RESULTS: When the position changed from standing to prone, LKCA and TK decreased significantly ( P<0.05), while SS, LL, PT, and PI-LL had no significant difference ( P>0.05). Pearson correlation analysis showed that LL was significantly correlated with SS and PI-LL in both standing and prone positions ( P<0.05), and the correlation strength between LL and SS in prone position was higher than that in standing position. In the standing position, LKCA was significantly correlated with SS and PT ( P<0.05). However, when the position changed from standing to prone, the correlation between LKCA and SS and PT disappeared, while PT and PI-LL was positive correlation ( P<0.05). The kyphotic flexibility was 25.13%-78.79%, with an average of 33.85%. CONCLUSION For the patients of old traumatic spinal fractures with kyphosis, the preoperative LKCA and TK decrease significantly from standing position to prone position, and the correlation between spinal and pelvic parameters also changed, which should be taken into account in the formulation of preoperative surgical plan.
Male ; Female ; Humans ; Spinal Fractures/surgery* ; Standing Position ; Retrospective Studies ; Lumbar Vertebrae/surgery* ; Kyphosis/surgery* ; Lordosis/surgery*

OBJECTIVE: To explore the effectiveness of a new point contact pedicle navigation template (referred to as "new navigation template" for simplicity) in assisting screw implantation in scoliosis correction surgery. METHODS: Twenty-five patients with scoliosis, who met the selection criteria between February 2020 and February 2023, were selected as the trial group. During the scoliosis correction surgery, the three-dimensional printed new navigation template was used to assist in screw implantation. Fifty patients who had undergone screw implantation with traditional free-hand implantation technique between February 2019 and February 2023 were matched according to the inclusion and exclusion criteria as the control group. There was no significant difference between the two groups ( P>0.05) in terms of gender, age, disease duration, Cobb angle on the coronal plane of the main curve, Cobb angle at the Bending position of the main curve, the position of the apical vertebrae of the main curve, and the number of vertebrae with the pedicle diameter lower than 50%/75% of the national average, and the number of patients whose apical vertebrae rotation exceeded 40°. The number of fused vertebrae, the number of pedicle screws, the time of pedicle screw implantation, implant bleeding, fluoroscopy frequency, and manual diversion frequency were compared between the two groups. The occurrence of implant complications was observed. Based on the X-ray films at 2 weeks after operation, the pedicle screw grading was recorded, the accuracy of the implant and the main curvature correction rate were calculated. RESULTS: Both groups successfully completed the surgeries. Among them, the trial group implanted 267 screws and fused 177 vertebrae; the control group implanted 523 screws and fused 358 vertebrae. There was no significant difference between the two groups ( P>0.05) in terms of the number of fused vertebrae, the number of pedicle screws, the pedicle screw grading and accuracy, and the main curvature correction rate. However, the time of pedicle screw implantation, implant bleeding, fluoroscopy frequency, and manual diversion frequency were significantly lower in trial group than in control group ( P<0.05). There was no complications related to screws implantation during or after operation in the two groups. CONCLUSION The new navigation template is suitable for all kinds of deformed vertebral lamina and articular process, which not only improves the accuracy of screw implantation, but also reduces the difficulty of operation, shortens the operation time, and reduces intraoperative bleeding.
Humans ; Orthopedic Procedures ; Pedicle Screws ; Retrospective Studies ; Scoliosis/surgery* ; Spinal Fusion/methods* ; Spine ; Surgery, Computer-Assisted/methods*

OBJECTIVE: To analyze the early effectiveness of unilateral biportal endoscopy (UBE) laminectomy in the treatment of two-level lumbar spinal stenosis (LSS). METHODS: The clinical data of 98 patients with two-level LSS treated with UBE between September 2020 and December 2021 were retrospectively analyzed. There were 53 males and 45 females with an average age of 59.9 years (range, 32-79 years). Among them, there were 56 cases of mixed spinal stenosis, 23 cases of central spinal canal stenosis, and 19 cases of nerve root canal stenosis. The duration of symptoms was 1.5- 10 years, with an average of 5.4 years. The operative segments were L _{2, 3} and L _{3, 4} in 2 cases, L _{3, 4} and L _{4, 5} in 29 cases, L _{4, 5} and L _5, S ₁ in 67 cases. All patients had different degrees of low back pain, among of which 76 cases were with unilateral lower extremity symptoms and 22 cases were with bilateral lower extremity symptoms. There were 29 cases of bilateral decompression in both segments, 63 cases of unilateral decompression in both segments, and 6 cases of unilateral decompression and bilateral decompression of each segment. The operation time, intraoperative blood loss, total incision length, hospitalization stay, ambulation time, and related complications were recorded. Visual analogue scale (VAS) score was used to assess the low back and leg pain before operation and at 3 days, 3 months after operation, and at last follow-up. The Oswestry disability index (ODI) was used to evaluate the functional recovery of lumbar spine before operation and at 3 months and last follow-up after operation. Modified MacNab criteria was used to evaluate clinical outcomes at last follow-up. Imaging examinations were performed before and after operation to measure the preservation rate of articular process, modified Pfirrmann scale, disc height (DH), lumbar lordosis angle (LLA), and cross-sectional area of the canal (CAC), and the CAC improvement rate was calculated. RESULTS: All patients underwent surgery successfully. The operation time was (106.7±25.1) minutes, the intraoperative blood loss was (67.7±14.2) mL, and the total incision length was (3.2±0.4) cm. The hospitalization stay was 8 (7, 9) days, and the ambulation time was 3 (3, 4) days. All the wounds healed by first intention. Dural tear occurred in 1 case during operation, and mild headache occurred in 1 case after operation. All patients were followed up 13-28 months with an average of 19.3 months, and there was no recurrence or reoperation during the follow-up. At last follow-up, the preservation rate of articular process was 84.7%±7.3%. The modified Pfirrmann scale and DH were significantly different from those before operation ( P<0.05), while the LLA was not significantly different from that before operation ( P=0.050). The CAC significantly improved ( P<0.05), and the CAC improvement rate was 108.1%±17.8%. The VAS scores of low back pain and leg pain and ODI at each time point after operation significantly improved when compared with those before operation, and the differences between each time points were significant ( P<0.05). According to the modified MacNab criteria, 63 cases were excellent, 25 cases were good, and 10 cases were fair, with an excellent and good rate of 89.8%. CONCLUSION UBE laminectomy is a safe and effective technique with little trauma and fast recovery for two-level LSS and the early effectiveness is satisfactory.
Male ; Female ; Humans ; Middle Aged ; Laminectomy ; Spinal Stenosis/surgery* ; Constriction, Pathologic/surgery* ; Low Back Pain ; Retrospective Studies ; Blood Loss, Surgical ; Endoscopy ; Lumbar Vertebrae/surgery* ; Spinal Fusion/methods* ; Decompression, Surgical ; Surgical Wound/surgery* ; Treatment Outcome

OBJECTIVE: To evaluate the application of surgical strategies for the treatment of cervical ossification of the posterior longitudinal ligament (OPLL) involving the C ₂ segment. METHODS: The literature about the surgery for cervical OPLL involving C ₂ segment was reviewed, and the indications, advantages, and disadvantages of surgery were summarized. RESULTS: For cervical OPLL involving the C ₂ segments, laminectomy is suitable for patients with OPLL involving multiple segments, often combined with screw fixation, and has the advantages of adequate decompression and restoration of cervical curvature, with the disadvantages of loss of cervical fixed segmental mobility. Canal-expansive laminoplasty is suitable for patients with positive K-line and has the advantages of simple operation and preservation of cervical segmental mobility, and the disadvantages include progression of ossification, axial symptoms, and fracture of the portal axis. Dome-like laminoplasty is suitable for patients without kyphosis/cervical instability and with negative R-line, and can reduce the occurrence of axial symptoms, with the disadvantage of limited decompression. The Shelter technique is suitable for patients with single/double segments and canal encroachment >50% and allows for direct decompression, but is technically demanding and involves risk of dural tear and nerve injury. Double-dome laminoplasty is suitable for patients without kyphosis/cervical instability. Its advantages are the reduction of damage to the cervical semispinal muscles and attachment points and maintenance of cervical curvature, but there is progress in postoperative ossification. CONCLUSION OPLL involving the C ₂ segment is a complex subtype of cervical OPLL, which is mainly treated through posterior surgery. However, the degree of spinal cord floatation is limited, and with the progress of ossification, the long-term effectiveness is poor. More research is needed to address the etiology of OPLL and to establish a systematic treatment strategy for cervical OPLL involving the C ₂ segment.
Humans ; Longitudinal Ligaments/surgery* ; Ossification of Posterior Longitudinal Ligament/surgery* ; Treatment Outcome ; Osteogenesis ; Decompression, Surgical/methods* ; Cervical Vertebrae/surgery* ; Laminoplasty/methods* ; Kyphosis/surgery* ; Retrospective Studies

OBJECTIVE: To review the application and progress of different minimally invasive spinal decompression in the treatment of lumbar spinal stenosis (LSS). METHODS: The domestic and foreign literature on the application of different minimally invasive spinal decompression in the treatment of LSS was extensively reviewed, and the advantages, disadvantages, and complications of different surgical methods were summarized. RESULTS: At present, minimally invasive spinal decompression mainly includes microscopic bilateral decompression, microendoscopic decompression, percutaneous endoscopic lumbar decompression, unilateral biportal endoscopy, and so on. Compared with traditional open surgery, different minimally invasive spinal decompression techniques can reduce the operation time, intraoperative blood loss, and postoperative pain of patients, thereby reducing hospital stay and saving treatment costs. CONCLUSION The indications of different minimally invasive spinal decompression are different, but there are certain advantages and disadvantages. When patients have clear surgical indications, individualized treatment plans should be formulated according to the symptoms and signs of patients, combined with imaging manifestations.
Humans ; Decompression, Surgical/methods* ; Endoscopy/methods* ; Laminectomy/methods* ; Lumbar Vertebrae/surgery* ; Minimally Invasive Surgical Procedures ; Retrospective Studies ; Spinal Stenosis/surgery* ; Treatment Outcome