Incidence and Risk Factors for the Development of Axial Symptoms Following Posterior Single-Door Laminoplasty: A Retrospective Analysis.

OBJECTIVE: Posterior single-door laminoplasty is a widely practiced clinical procedure, but the occurrence of postoperative axial syndrome (AS) remains a significant concern. The aim of this study was to identify risk factors associated with AS and develop a risk prediction model. METHODS: Clinical data from 226 patients who underwent posterior single-door laminoplasty between June 2017 and June 2022 were collected. Through Logistic model analysis, the risk factors of AS are clarified and the intensity of each risk factor is explained in the form of forest plot. Subsequently, we constructed a predictive model and plotted receiver operating characteristic curves to assess the model's predictive value. RESULTS: In the end, 87 cases were diagnosed with AS, resulting in an incidence rate of 38.5%. Logistic regression analysis revealed that preoperative encroachment rate of anterior spinal canal (pre-op ERASC), intraoperative facet joints destruction, intraoperative open-door angle, postoperative loss of cervical curvature, and postoperative loss of cervical range of motion were independent risk factors for AS. Conversely, preoperative cervical curvature (pre-op CC) and postoperation early function training were protective factors against AS. The Youden index indicated that the cutoff values for pre-op ERASC and pre-op CC were 26.6°and 16.5, respectively. The risk prediction model for AS was constructed and a nomogram was plotted. The model has high clinical value. CONCLUSIONS: Pre-op ERASC, pre-op CC, intraoperative facet joints destruction, intraoperative open-door angle, postoperative loss of cervical curvature, postoperative loss of cervical range of motion, and postoperation early function training are independent influencing factors for AS occurrence. The risk model has good practicability.

Analysis of risk factors for axial symptoms after posterior cervical open-door laminoplasty.

BACKGROUND: Laminoplasty (LP), a procedure commonly used to treat cervical spondylotic myelopathy (CSM), often results in the development of axial symptoms (AS) postoperatively. This study aims to analyze the risk factors associated with the occurrence of AS after LP. METHODS: We collected and evaluated clinical data from 264 patients with CSM who underwent LP treatment at our institution from January 2018 to January 2022 through a single-center retrospective study. Of the patients, 153 were male and 111 were female, with an average age of 58.1 ± 6.7 years. All patients underwent C3-7 posterior laminoplasty. Based on the occurrence of postoperative axial symptoms, the patients were divided into an AS group and a non-AS group. General information, including age, gender, disease duration, Japanese Orthopaedic Association (JOA) score, postoperation early function training, and collar-wearing time, was recorded and compared between the two groups. Surgical-related data, such as operative segments, surgical time, intraoperative blood loss, intraoperative facet joint destruction, and destruction of the C7 spinous process muscle insertion, were also compared. Imaging data, including preoperative cervical curvature, cervical range of motion, preoperative encroachment rate of the anterior spinal canal, and angle of laminar opening, were collected. Univariate and multivariate logistic regression analyses were used to identify risk factors for the development of AS after LP, and receiver operator characteristic (ROC) curves were utilized to explore the optimal preoperative parameters. RESULTS: All 264 patients successfully underwent surgery and were followed up for an average of 19.5 ± 6.8 months. At the 6-month follow-up, 117 patients were diagnosed with AS, resulting in an incidence rate of 40.2%. The multivariate logistic regression analysis identified that preoperative encroachment rate of anterior spinal canal (Pre-op ERASC), intraoperative facet joints destruction (Intra-op FJD), intraoperative open-door angle (Intra-op OA), destroy the C7 spinous process muscle insertion (Destroy C7 SPMI), postoperative loss of cervical curvature (Post-op LCC), and postoperative loss of cervical range of motion (Post-op LCROM) were independent risk factors for AS. Conversely, preoperative cervical curvature (Pre-op CC) and postoperation early function training (Post-op EFT) were protective factors against AS. According to the ROC curve, the cutoff values for preoperative anterior spinal canal occupation rate and preoperative cervical curvature were 28.5% and 16.5°, respectively. When the preoperative anterior spinal canal occupation rate was greater than 28.5% or the preoperative cervical curvature was less than 16.5°, AS was more likely to occur after surgery. CONCLUSION: High preoperative anterior spinal canal occupation rate, facet joint damage during surgery, C7 spinous process muscle stop point damage, larger angle of laminar opening, and greater postoperative cervical curvature loss and cervical range of motion loss are associated with an increased risk of developing AS after cervical laminoplasty. Conversely, a larger preoperative cervical curvature and early postoperative functional exercises can help reduce the occurrence of AS.

Risk factors analysis and risk prediction model construction of non-specific low back pain: an ambidirectional cohort study.

PURPOSE: Non-specific low back pain (NLBP) is a common clinical condition that affects approximately 60-80% of adults worldwide. However, there is currently a lack of scientific prediction and evaluation systems in clinical practice. The purpose of this study was to analyze the risk factors of NLBP and construct a risk prediction model. METHODS: We collected baseline data from 707 patients who met the inclusion criteria and were treated at the Sixth Hospital of Ningbo from December 2020 to December 2022. Logistic regression and LASSO regression were used to screen independent risk factors that influence the onset of NLBP and to construct a risk prediction model. The sensitivity and specificity of the model were evaluated by tenfold cross-validation, and internal validation was performed in the validation set. RESULTS: Age, gender, BMI, education level, marital status, exercise frequency, history of low back pain, labor intensity, working posture, exposure to vibration sources, and psychological status were found to be significantly associated with the onset of NLBP. Using these 11 predictive factors, a nomogram was constructed, and the area under the ROC curve of the training set was 0.835 (95% CI 0.756-0.914), with a sensitivity of 0.771 and a specificity of 0.800. The area under the ROC curve of the validation set was 0.762 (95% CI 0.665-0.858), with a sensitivity of 0.800 and a specificity of 0.600, indicating that the predictive value of the model for the diagnosis of NLBP was high. In addition, the calibration curve showed a high degree of consistency between the predicted and actual survival probabilities. CONCLUSION: We have developed a preliminary predictive model for NLBP and constructed a nomogram to predict the onset of NLBP. The model demonstrated good performance and may be useful for the prevention and treatment of NLBP in clinical practice.

Analysis of risk factors for contralateral symptomatic foraminal stenosis after unilateral transforaminal lumbar interbody fusion.

PURPOSE: To analyze the risk factors of contralateral symptomatic foraminal stenosis (FS) after unilateral transforaminal lumbar interbody fusion (TLIF) and to guide and standardize the operation process of unilateral TLIF to reduce the occurrence of contralateral symptomatic FS. METHODS: A retrospective study was undertaken on 487 patients with lumbar degeneration who underwent unilateral TLIF in the Department of Spinal Surgery of Ningbo Sixth Hospital between January 2017 and January 2021, comprising 269 males and 218 females, with a mean age of 57.1 years (range, 48-77 years). Cases of intraoperative improper operations, such as screw deviation, postoperative hematoma, and contralateral disc herniation, were excluded, and cases of nerve root symptoms caused by contralateral FS were analyzed. Post-surgery, 23 patients with nerve root symptoms caused by contralateral FS were categorized as group A, and 60 patients without nerve root symptoms were randomly selected as group B during the same period. The general data (gender, age, body mass index (BMI), bone mineral density (BMD), and diagnosis) and imaging parameters before and after operation (including contralateral foramen area (CFA), lumbar lordosis angle (LL), segmental lordosis angle (SL), disc height (DH), foramen height (FH), foramen width (FW), fusion cage position, and the difference between postoperative and preoperative) were compared between the two groups. Univariate analysis was performed, and multivariate analysis was undertaken through logistics analysis to determine the independent risk factors. Additionally, the clinical outcomes of the two groups were compared immediately before surgery and one year after surgery, using the visual analogue scale (VAS) score and the Japanese Orthopaedic Association (JOA) score for evaluation. RESULTS: The patients in this study were followed up for a period of 19-25 (22.8atien months. Among them, 23 cases (4.72% incidence) were diagnosed with contralaterally symptomatic FS after the surgery. Univariate analysis indicated significant differences between the two groups in CFA, SL, FW, and cage coronal position. Logistic regression analysis identified preoperative contralateral foramen area (OR = 1.176, 95% CI (1.012, 1.367)), small segmental lordosis angle (OR = 2.225, 95% CI (1.124, 4.406)), small intervertebral foramen width (OR = 2.706, 95% CI (1.028, 7.118)), and cage coronal position not crossing the midline (OR = 1.567, 95% CI (1.142, 2.149)) as independent risk factors for contralateral symptomatic FS after unilateral TLIF. However, there was no statistically significant difference in the pain VAS score between the two groups one year after the operation. In contrast, there was a significant difference in the JOA score between the two groups. CONCLUSION: The identified risk factors for contralateral symptomatic FS after TLIF include preoperative contralateral intervertebral foramen stenosis, a small segmental lordosis angle, a small intervertebral foramen width, and the coronal position of the cage not crossing the midline. For patients with these risk factors, it is recommended to carefully lock the screw rod during the recovery of lumbar lordosis and ensure that the coronal position of the fusion cage is implanted beyond the midline. If necessary, preventive decompression should also be considered. However, this study did not quantify the imaging data for each risk factor, and further research is needed to improve our understanding of the topic.

Effect of preoperative contralateral foramen stenosis on contralateral root symptoms after unilateral transforaminal lumbar interbody fusion: a ambispective cohort study.

PURPOSE: To evaluate the correlation between the degree of preoperative contralateral foraminal stenosis(CFS) and the incidence of contralateral root symptoms after unilateral transforaminal lumbar interbody fusion(TLIF) and to evaluate the appropriate candidate of preventive decompression according to the degree of preoperative contralateral foraminal stenosis. METHODS: An ambispective cohort study was conducted to investigate the incidence of contralateral root symptoms after unilateral transforaminal lumbar interbody fusion (TLIF) and the effectiveness of preventive decompression. A total of 411 patients were included in the study, all of whom met the inclusion and exclusion criteria and underwent surgery at the Department of Spinal Surgery, Ningbo Sixth Hospital, between January 2017 and February 2021. The study was divided into two groups: retrospective cohort study A and prospective cohort study B. The 187 patients included in study A from January 2017 to January 2019 did not receive preventive decompression. They were divided into four groups based on the degree of preoperative contralateral intervertebral foramen stenosis: no stenosis group A1, mild stenosis group A2, moderate stenosis group A3, and severe stenosis group A4. A Spearman rank correlation analysis was used to evaluate the correlation between the preoperative contralateral foramen stenosis degree and the incidence of contralateral root symptoms after unilateral TLIF. From February 2019 to February 2021, 224 patients were included in the prospective cohort group B. The decision to perform preventive decompression during the operation was based on the degree of preoperative contralateral foramen stenosis. Severe intervertebral foramen stenosis was treated with preventive decompression as group B1, while the rest were not treated with preventive decompression as group B2. The baseline data, surgical-related indicators, the incidence of contralateral root symptoms, clinical efficacy, imaging results, and other complications were compared between group A4 and group B1. RESULTS: All 411 patients completed the operation and were followed up for an average of 13.5 ± 2.8 months. In the retrospective study, there was no significant difference in baseline data among the four groups (P > 0.05). The incidence of postoperative contralateral root symptoms increased gradually, and a weak positive correlation was found between the degree of preoperative intervertebral foramen stenosis and the incidence of postoperative root symptoms (rs = 0.304, P < 0.001). In the prospective study, there was no significant difference in baseline data between the two groups. The operation time and blood loss in group A4 were less than those in group B1 (P < 0.05). The incidence of contralateral root symptoms in group A4 was higher than that in group B1 (P = 0.003). However, there was no significant difference in leg VAS score and ODI index between the two groups at 3 months after the operation (P > 0.05). There was no significant difference in cage position, intervertebral fusion rate, and lumbar stability between the two groups (P > 0.05). No incisional infection occurred after the operation. No pedicle screw loosening, displacement, fracture, or interbody fusion cage displacement occurred during follow-up. CONCLUSION: This study found a weak positive correlation between the degree of preoperative contralateral foramen stenosis and the incidence of contralateral root symptoms after unilateral TLIF. Intraoperative preventive decompression of the contralateral side may prolong the operation time and increase intraoperative blood loss to some extent. However, when the contralateral intervertebral foramen stenosis reaches the severe level, it is recommended to perform preventive decompression during the operation. This approach can reduce the incidence of postoperative contralateral root symptoms while ensuring clinical efficacy.

[Treatment strategy and curative effect analysis of os odontoideum complicated with atlantoaxial joint dislocation].

OBJECTIVE: To explore the treatment strategy and clinical efficacy for os odontoideum complicated with atlantoaxial dislocation. METHODS: The clinical data of 17 patients with os odontoideum complicated with atlantoaxial dislocation surgically treated from January 2006 to January 2015 were retrospectively analyzed, including 7 males and 10 females, aged 17 to 53 (43.1±11.3) years old;course of disease was 3 to 27(10.2±6.9) months. All patients received cranial traction before operation, 12 of 14 patients with reducible dislocation were treated by posterior atlantoaxial fixation and fusion, and 2 patients with atlantooccipital deformity were treated by posterior occipitocervical fixation and fusion;3 patients with irreducible alantoaxial dislocation were treated by transoral approach decompression combined with posterior atlantoaxial fixation and fusion. The operation time, intraoperative blood loss and perioperative complications were recorded. Visual analogue scale (VAS) and Japanese Orthopaedic Association (JOA) score were used to evaluate the change of neck pain and neurological function. Atlantoaxial joint fusion rate was evaluated by CT scan. RESULTS: The operation time of posterior fixation and fusion ranged from 86 to 170 (92.2±27.5) min, and the intraoperative blood loss was 200-350 (250.7±65.2) ml. No vertebral artery injury and spinal cord injury were recorded. Among the patients underwent atlantoaxial fixation and fusion, 1 patient with reducible dislocation fixed by C2 laminar screw lost reduction after primary operation, and received anterior release again and finally occipitocervical fusion. All patients were followed up for 15 to 58 (32.0±12.2) months. VAS score was decreased from preoperative 4.2±0.9 to 1.3±0.7 at final follow up and the JOA score was improved from preoperative 11.2±1.2 to 16.9±0.8 at final follow-up. CT scan confirmed that the atlantoaxial or occipitocervical fusion wasgood, and the fusion time was 5 to 9 (6.7±0.6) months. CONCLUSION: Surgical treatment of os odontoideum complicated with atlantoaxial dislocation can achieve satisfactory results, improve the patient's neurological function and improve the quality of life, however the surgical options needs to be individualized.

[Comparison of the effects of injured vertebra pedicle fixation combined with vertebroplasty and vertebra pedicle screw fixation combined with vertebroplasty in the treatment of osteoporotic thoracolumbar burst fractures].

OBJECTIVE: To assess the curative effects of injured vertebra pedicle fixation combined with vertebroplasty and short-segment pedicle screw fixation combined with vertebroplasty in treatment of osteoporotic thoracolumbar burst fractures. METHODS: Seventy patients with osteoporotic thoracolumbar burst fractures who met the inclusion criteria were collected in the study from January 2015 to December 2017. Among them, 35 patients were treated with injured vertebra pedicle fixation combined with vertebroplasty (group A), including 20 males and 15 females, aged from 55 to 74 years with an average of (64.03± 7.82) years. Twenty-six cases were type A3 and 9 cases were type A4 according to the AO typing;another 35 patients were treated with short segment pedicle screw fixation combined with vertebroplasty (group B), including 18 males and 17 females, aged from 54 to 72 years with an average of (62.78±6.40) years. Twenty-eight cases were type A3 and 7 cases were type A4 according to AO typing. Operation length, intraoperative bleeding volume, complication, imaging parameters and clinical effects were compared between the two groups. RESULTS: All the patients were followed up for at least 12 months. There were no significant differences in gender, age, injury site, preoperative VAS, Cobb angle, and injured vertebral height before surgery. There were no significant differences in operation length, intraoperative bleeding volume between two groups. In terms of VAS scores before surgery, 1 week after surgery, and at the final follow up, group A was 5.5 ±2.5, 1.8 ±0.8, 0.9 ±0.4, group B was 5.4 ± 2.3, 1.7±0.6, 1.2±1.8, respectively;injured vertebral height was (40.4±8.8)%, (92.0±4.9)%, (87.1±3.8)% in group A, and (41.2±6.6)%, (93.2±4.6)%, (80.0±4.3)% in group B;Cobb angle was (18.4±6.9) °, (2.8±2.2) °, (4.2±2.6) ° in group A, and (16.8±7.2) °, (2.7±2.5) °, (6.0±2.4) ° in group B. There were significant differences in the 3 parameters above before the operation and at the final follow up in all groups (P<0.05). There were significant differences in the Cobb angle and injured vertebral height between 1 week after operation and at the final follow up (P<0.05). At the final follow up, injured vertebral height in group A was obviously better than that in group B (P<0.05). Internal fixation failure occurred in 2 cases from the group A, and occurred in 4 cases from the group B. There were no neurological complications in both groups. CONCLUSION: For osteoporotic thoracolumbar vertebral burst fractures, injured vertebra pedicle fixation combined with vertebroplasty and vertebra pedicle screw fixation combined with vertebroplasty can achieve good clinical effects. However, injured vertebra pedicle fixation combined with vertebroplasty is better at maintaining postoperative vertebral height and sagittal arrangement, and reducing internal fixation related complications. The treatment strategy is worthy of application and promotion.

Safe trajectory for an occipital condyle screw: A computer simulation study.

OBJECTIVE: The purpose of this study was to evaluate the feasibility of posterior occipital condyle screw (OCS) placement analysis of the safe trajectory area for screw insertion. METHODS: Computed tomographic angiography scans of patients (46 males and 27 females) with normal occipitocervical structures were obtained consecutively. Vertebral artery (VA)-occiput distance <4.0 mm was defined as "unfeasible" for OCS fixation, and occipital-atlas angulation was measured to assess the feasibility of screw placement. Next, the placement of 3.5 mm diameter OCS was simulated, the probability of breach of structures surrounding occipital condyles was calculated, and placement parameters were analyzed. RESULTS: OCS placement was feasible in 91.1% (133/146) of occipital condyles, and the feasible probability also presented a significant sex-related difference: The probability was higher for males than for females (95.7% vs. 83.3%, p < 0.05). The incidence of anatomical structures injured under screw placement limitation was 18.8% (VA), 81.2% (hypoglossal canal), 59.4% (occipital-atlas joint), and 40.6% (occiput bone surface). There were no significant differences between the left and right condyles in relation to the measured parameters (p > 0.05). The screw range of motion was significantly smaller in females than in males (p < 0.05). The feasibility of OCS placement and OCS range of motion were significantly greater in the kyphosis group (>5°) than in the other two groups (p < 0.05). CONCLUSION: OCS placement is a feasible technique for occipital-cervical fusion. The male group and occipitocervical region kyphosis group had a wider available space for OCS placement. Tangent angulation may be useful for the accurate and safe placement of an OCS.

Modified Broström Repair With and Without Augmentation Using Suture Tape for Chronic Lateral Ankle Instability.

OBJECTIVE: To compare the clinical and radiological outcome between the modified Broström repair with augmentation using suture tape (MBA) and the modified Broström repair (MB) for patients with chronic lateral ankle instability. METHODS: A retrospective study was performed in Ningbo No. 6 Hospital. The study included 53 patients who underwent surgical treatment from March 2014 to July 2016 and were followed for 2 years. A total of 25 patients underwent modified Broström repair with augmentation using suture tape, and 28 patients were treated with modified Broström repair. Patients were evaluated using the American Orthopedic Foot and Ankle Scale (AOFAS) hindfoot scale, the Foot and Ankle Ability Measure (FAAM) score, range of motion (ROM), and the visual analogue scale (VAS). The talar tilt angle (TTA) and anterior talar translation (ATT) were used to evaluate the mechanical stability. All radiological outcomes were measured by two orthopaedic surgeons, with the measurements repeated 3 days later. RESULTS: The mean age of the patients was 26.6 ± 17.8 years in the MBA group and 28.1 ± 19.4 years in the MB group, and no statistical difference in preoperative data was found between two groups. There were significant differences before and after the operation within the groups. Both groups achieved satisfactory outcomes, and significant improvements (VAS, FAAM, AOFAS, TTA, and ATT) were observed between the 1-year follow-up and final follow-up (P < 0.05). The MBA group showed significant improvement in the FAAM Sport (87.1 ± 5.4 vs 78.2 ± 12.0, P = 0.001) and total scores (93.1 ± 2.3 vs 90.5 ± 5.1, P = 0.027) at the final follow-up compared with the MB group, and for the other outcomes, there were no significant differences between the two groups. CONCLUSION: The modified Broström repair with augmentation using suture tap for chronic lateral ankle instability achieves a better outcome; however, further research is necessary.

Missed manubriosternal dislocation in patient with thoracolumbar fracture, a case report.

BACKGROUND: Spine fractures combined with sternal injury are most commonly occur in the thoracic region. Lower cervical and thoracolumbar injuries have also been reported, especially for the patients with manubriosternal dislocation. The type of spine injury is easily recognized in initial presentation, but we may miss the sternal fracture and manubriosternal dislocation. CASE PRESENTATION: A 23-year-old male patient complained with chest, right ankle, and lumbar pain after a fall at ground level, with diagnosis of right distal tibial fracture, sternal fracture, calcaneus fracture, and L2 vertebral fracture. However, neurologically he was completely normal. He underwent the operation for his lower extremity and spine, but we missed his manubriosternal dislocation after discharged. After one month, he came to the clinic with complained of chest pain, the imaging exams showed anterior dislocation of manubriosternal joint. We chose conservative treatment for manubriosternal dislocation. He was followed up at monthly intervals and radiographs along with computerized tomography showed satisfactory in fracture healing of lumber and the sternal fracture. However, the manubriosternal dislocation was malunioned. The patient had appearance deformity of the manubriosternal joint. CONCLUSION: This case supports the concept of the existence and clinical relevance of the thoracic cage theory, the thoracolumbar vertebrae should also be included in the thoracic cage theory.

[Case-control study of pedicle screw fixation combined with vertebroplasty and injured vertebra pedicle fixation in treatment of osteoporotic thoracolumbar burst fractures].

OBJECTIVE: To compare the curative effect of short-segment pedicle screw fixation combined with vertebroplasty and injured vertebra pedicle fixation in treating osteoporotic thoracolumbar burst fractures. METHODS: A retrospective study was performed for 52 patients with thoracolumbar burst fractures from August 2010 to August 2015. Among them, 27 patients(group A) were treated with short-segment pedicle screw fixation combined with vertebroplasty, including 17 males and 10 females, aged from 54 to 68 years old with an average of(61.01±5.41) years, 16 cases were type A3 and 11 cases were type A4 according the new AO typing. Other 25 patients (group B) were treated with short-segment pedicle screw fixation combined with injured vertebra pedicle fixation, including 12 males and 13 females, aged from 55 to 66 years old with an average of (59.28±6.12) years, 18 cases were type A3 and 7 cases were type A4 according the new AO typing. Operation time, intraoperative bleeding volume, complication, image data and clinical effect were compared between two groups. RESULTS: All the patients were followed up for 12 to 15 months with an average of (12.4±2.1)months. There was no significant difference in general data(including gender, age, injured site, preoperative VAS score, Cobb angle, injured vertebral anterior border height) between two groups. There was no significant differences in operation time, intraoperative bleeding volume between two groups. Preoperative, one week after operation and final follow-up, VAS scores were 5.2±0.5, 1.2±0.2, 0.8±0.1 respectively in group A and 5.0±0.6, 2.5±0.4, 1.3±0.2 in group B; injured vertebral anterior border height were (49.4±6.8)%, ( 94.5±1.2)%, ( 94.1±3.7)% respectively in group A and (48.2±7.0)%, ( 94.3±4.1)%, ( 90.0±2.3)% in group B;Cobb angles were (20.4±5.2) °, (2.5±1.8) °, (4.4±1.7)° respectively in group A and (19.8±6.8)°, (2.4±1.7)°, (7.0±1.2)° in group B. At final follow-up, VAS, Cobb angle, injured vertebral anterior border height in two groups were obviously improved(P<0.05). Postoperative at 1 week and final follow-up, VAS score of group A was lower than that of group B(P<0.05);and there was no significant difference in Cobb angle between two groups(P>0.05); there was significant difference in injured vertebral anterior border height between two groups(P<0.05). The complication of internal fixation failure had 1 case in group A and 4 cases in group B. CONCLUSIONS: For the treatment of single osteoporotic thoracolumbar burst fractures, short-segment pedicle screw fixation combined with vertebroplasty is better than combined with injured vertebra pedicle fixation in clinical effect, it can relieve pain, maintain injured vertebral height and sagittal alinement, reduce the complications associated with internal fixation, and be worth spread in clinic.

[Percutaneous pedicle screw fixation combined with limited-open decompression technique for thoracolumbar fractures with neurologic deficit].

OBJECTIVE: To evaluate the clinical effects of percutaneous pedicle screw fixation combined with limited open decompression technique for the treatment of thoracolumbar fractures with neurologic deficit. METHODS: The clinical data of 76 patients with thoracolumbar fractures with neurologic deficit underwent percutaneous pedicle screw fixation combined with limited open decompression technique from June 2010 to June 2014 were retrospectively analyzed. There were 45 males and 31 femals, aged from 17 to 56 years with an average of 32.5 years old. According to the classification of Denis, 33 cases were type A, 26 cases were type B, 17 cases were type C. According to the criterion of American Spinal Injury Association(ASIA), 13 cases were grade A, 9 cases were grade B, 21 cases were grade C, 33 cases were grade D. The operative time, intraoperative blood loss, postoperative internal fixation lossening and breakage were recorded. The informations of the Cobb angle, the anterior height of injured vertebra, canal stenosis were observed before operation, 3 days after operation, and the final follow-up. The improvement of neurologic function were analyzed at final follow-up. RESULTS: All the patients were followed up from 13 to 47 months with an average of 32.1 months. The mean operative time was 159 min (136 to 218 min) and the intraoperative blood loss was 225 ml(150 to 360 ml). The anterior height of injured vertebra was increased from (52.0±5.9)% before operation to (87.2±1.8)% at 3 days after operation, and (86.1±1.5)% at final follow-up (F=45.27, P=0.000); the Cobb angle was decreased from (29.7±8.2)° before operation to (5.7±2.9)° at 3 days after operation, and (5.9±3.6)° at final follow-up (F=34.62, P=0.000); the canal stenosis was decreased from (37.5±7.2)% before operation to (12.3±3.3)% at 3 days after operation, and (11.9±3.1)% at final follow-up(F=37.02, P=0.000); there was no significant differences between postoperative 3 days and the final follow-up about the above parametres(P>0.05). According to ASIA criterion, the spinal cord function was classified as grade A in 13 cases, grade B in 0 cases, grade C in 10 cases, grade D in 21 cases and grade E in 32 cases at final follow-up. Internal fixation lossening and breakage occurred in 2 cases. CONCLUSIONS: Percutaneous pedicle screw fixation combined with limited open decompression technique can obtain satisfactory clinical effect for patients with thoracolumbar fractures with neurologic deficit, and have a good recovery of nerve function can be observed.

[French door segmented laminectomy decompression for severe cervical ossification of posterior longitudinal ligament complicated with spinal cord injury].

OBJECTIVE: To evaluate the clinical effects of French door segmented laminectomy decompression for severe cervical OPLL complicated with spinal cord injury. METHODS: The clinical data of 38 patients with serious cervical OPLL complicated with spinal cord injury were retrospectively analyzed and these patients were treated with French door segmented laminectomy decompression and internal fixation from June 2012 to June 2014. There were 25 males and 13 females, aged from 42 to 78 years with an average of 58.2 years. Of them, 35 cases suffered from aggravating neurological symptoms with a definite precipitating factor. Spinal cord injury was related to minor injury of the neck, such as hyperextension of the neck in 3 cases. Preoperative Japanese Orthopaedic Score (JOA) was 8.1±1.7 and Neck Disability Index (NDI) was 19.8±4.4. Preoperative CT scans showed the range of OPLL was more than three segments. The spinal canal was occupied 50% to 85% with an average of 70.7%. RESULTS: All the patients were followed up for 10 to 24 months with an average of 15.6 months. The operative time was 90 to 150 min with an average of 120 min and blood loss was 300 to 800 ml with an average of (480±80) ml. At final follow-up, NDI and JOA were 7.5±2.5 and 13.5±2.0, respectively, and they were obviously improved compared with preoperation. Preoperative cervical Cobb angle was (8.10±2.70)° and at final follow-up was (15.60±1.80)°, and there was significant difference between preoperative and postoperative (P<0.05). Deep infection occurred in 1 case, epidural hematoma in 1 case, C5 nerve root palsy in 3 cases, and axial symptom in 8 cases after operation. No serious complications, such as vertebral artery injury, cerebrospinal fluid leakage, deterioration of neurological dysfunction, or internal fixation failure was found. CONCLUSIONS: French door segmented laminectomy decompression is safe and feasible for severe cervical OPLL complicated with spinal cord injury, and it is worth to be popularized in future.

[The shor-term clinical outcomes and safety of extreme lateral interbody fusion combined with percutaneous pedicle screw fixation for the treatment of degenerative lumbar disease].

OBJECTIVE: To evaluate the early efficacy and safety of extreme lateral interbody fusion (XLIF) combined with percutaneous pedicle screw fixation for lumbar degenerative disease. METHODS: From January 2013 to June 2014, 13 patients with degenerative lumbar disease were treated with XLIF combined with percutaneous pedicle screw fixation, including 8 cases of lumbar instability, 5 cases of mild to moderate lumbar spondylolisthesis;there were 5 males and 8 females, aged from 56 to 73 years with an average of 62.1 years. All patients were single segment fusion. Operation time, perioperative bleeding and perioperative complications were recorded. Visual analogue scale (VAS) and Oswestry Disability Index (ODI) were used to evaluate the clinical efficacy. Interbody fusion rate was observed and the intervertebral foramen area changes were compared preoperation and postoperation by X-rays and CT scanning. RESULTS: The mean operation time and perioperative bleeding in the patients respectively was(62.8±5.2) min and(82.5±22.6) ml. One case occurred in the numbness of femoribus internus and 1 case occurred in the muscle weakness of hip flexion after operation, both of them recovered within 2 weeks. All the patients were followed up from 12 to 19 months with an average of 15.6 months. VAS was decreased from preoperative 7.31±0.75 to 2.31±0.75 at final follow-up(P<0.05); ODI was decreased from preoperative (42.58±1.55)% to (12.55±0.84)% at final follow-up(P<0.05). At final follow-up, CT scanning confirmed 8 cases completely fused and 5 cases partly fused;the intervertebral foramen area was increased from preoperative (94.86±2.44)mm2 to (150.70±7.02)mm2(P<0.05). CONCLUSIONS: Extreme lateral interbody fusion combined with percutaneous pedicle screw fixation is an ideal method and can obtain early good clinical effects in treating lumbar degenerative disease.

[Mini-open trans-spatium intermuscular versus percutaneous short-segment pedicle fixation for the treatment of thoracolumbar mono-segmental vertebral fractures].

OBJECTIVE: To compare the clinical effects and radiographic outcomes of mini-open trans-spatium intermuscular and percutaneous short-segment pedicle fixation in treating thoracolumbar mono-segmental vertebral fractures without neurological deficits. METHODS: From August 2009 and August 2012, 95 patients with thoracolumbar mono-segmental vertebral fractures without neurological deficits were treated with short-segment pedicle fixation through mini-open trans-spatium intermuscular or percutaneous approach. There were 65 males and 30 females, aged from 16 to 60 years old with an average of 42 years. The mini-open trans-spatium intermuscular approach was used in 58 cases (group A) and the percutaneous approach was used in 37 cases (group B). Total incision length, operative time, intraoperative bleeding, fluoroscopy, hospitalization cost were compared between two groups. Visual analog scale (VAS) and radiographic outcomes were compared between two groups. RESULTS: All patients were followed up from 12 to 36 months with an average of 19.6 months. No complications such as incision infection, internal fixation loosening and breakage were found. In group A, fluoroscopy time was short and hospitalization cost was lower than that of group B (P<0.05). But the total incision length in group B was smaller than that of group A (P<0.05). There was no significant differences in operative time, intraoperative bleeding, postoperative VAS and radiographic outcomes between two groups (P>0.05). Postoperative VAS and radiographic outcomes were improved than that of preoperative (P<0.05). CONCLUSION: The mini-open trans-spatium intermuscular and percutaneous short-segment pedicle fixation have similar clinical effects and radiographic outcomes in treating thoracolumbar mono-segmental vertebral fractures without neurological deficits. However, in this study, the mini-open trans-spatium intermuscular approach has a short learning curve and more advantages in hospitalization cost and intraoperative radiation exposure times, and is recommendable.

Radiological studies on the best entry point and trajectory of anterior cervical pedicle screw in the lower cervical spine.

OBJECTIVE: To explore the best entry point and trajectory of anterior cervical transpedicular screws in the lower cervical spine by radiological studies, and provide reference for clinical application. METHODS: Fifty patients were scanned by computed tomography and confirmed no obvious defect of the cervical spine. On horizontal axis, camber angle (α) and axial length (AL) were measured from C3 to C7. On sagittal view, the cranial or caudal angle (ß) and sagittal length (SL) were also measured from C3 to C7. On the sagittal and horizontal planes vertebrae were respectively divided into four areas, ordered 1-4, on the anterior side of the pedicle. The areas and angles of pedicle intersect into the vertebral body were recorded. We inserted six anterior pedicle screws into the lower cervical spine of three patients by this technique. RESULTS: On transverse plane, camber angle (α) of C3-C5 increased gradually, while it decreased from C5 to C7. On sagittal view, C3 and C4 pedicles showed cranial tilting, while C5 to C7 were caudally tilted. AL and SL values increased gradually from C3 to C7. The number of the intersections of C3-C7 in each area was also different. Six pedicle screws of three cases were inserted into the lower cervical spine with proper placement and no complications. CONCLUSION: Anterior transpedicular screw (ATPS) is a theoretically feasible option for internal fixation. The technique described in this paper was subsequently used in three patients without complication. Future improvement of ATPS insertion remains necessary for this technically demanding procedure.