Fusion Fixation Research Articles

Clinical study of movable external fixation for elbow tuberculosis

To compare clinical effect of movable external fixation and fusion fixation for the treatment of elbow tuberculosis. From October 2013 to June 2019, 52 patients with elbow tuberculosis treated with standard antituberculosis therapy were divided into movable external fixation group and fusion fixation group according to treatment methods. In group A, there were 25 patients, including 11 males and 14 females, aged from 24 to 75 years old with an average of (42.81± 9.01) years old; the courses of diseases ranged from 2 to 9 months with an average of (3.96±1.45) months. In group B, there were 27 patients, including 15 males and 12 females, aged from 23 to 77 years old with an averageof (44.08±7.44) years old; the courses of diseases ranged from 2 to 7 months with an average of (3.88±1.67) months. All patients were performed focus debridement. Intraoperative blood loss, operative time were compared between two groups. VAS score before operation, 2 weeks and 12 months after operation were applied to evaluate pain relieve;Mayo elbow performance score (MEPS) before operation, 1 and 12 months after operation were used to evaluate clinical effect;changes of erythrocyte sedimentation rate (ESR) and Creactive protein, CRP) before operation, 3 weeks after antituberculosis therapy, 1 week and 6 months after operation were compared between two groups. All patients were followed up from 12 to 20 months with an average of (13.50±4.85) months. No mixed infection and recurrence of tuberculosis occurred. There were no statistical differences in intraoperative blood loss and operative time(P>0.05). There was difference in postoperative VAS score at 2 weeks between movable external fixation group (5.15±0.95) and fusion fixation group (4.04±0.84)(P<0.01);while no difference in postoperative VAS score at 12 months between two groups (P>0.05). No difference in ESR and CRP level between two groups before and after operation (P>0.05). Postoperative Mayo score at 1 and 12 months in movable external fixation group were (78.15±7.83) and (90.19±7.13);in fusion fixation group were (70.40±7.61) and (82.60±8.38);there were differences in Mayo score at different time points between two groups(P<0.01). For elbow tuberculosis, movable external fixation and fusion fixation have equal effect in operative time, amount of bleeding and control of tuberculosis infection indicator. Movable external fixation need earlier functional exercise, not conducive to pain relief at early stage, which may be better than fusion fixation, it is worth clinical promoting.

Augmentation of Internal Fixation With Multiplanar External Fixator in High Risk Hind Foot Fusion Patients

Category:Hindfoot; Ankle; DiabetesIntroduction/Purpose:Achieving adequate fixation is a critical component for successful fusion. Internal fixation can be compromised in the setting of poor bone quality due to open trauma, infection, osteoporosis, neuropathic arthropathy resulting in published ankle non-union rates of 38% in high risk patients. These failures may be magnified by weightbearing non-compliance.While the use of multiplanar external fixation (MEF) alone can be utilized - it can often require an extended period of time within the frame (mean 18 weeks, range 9-28 weeks) and complications such as pin site infections. We hypothesized that hybrid fixation, MEF in conjunction with internal fixation, will provide adequate stability elevating the fusion rates in complex fusion cases while allowing early weight bearing and reduces the MEF time and infection rate.Methods:Eleven patients were identified that demonstrate significant risk factors for a successful fusion (infection, charcot, neuropathy, smoking, history of non-union) that were treated with internal fixation augmented with MEF. Patients with an active infection underwent surgical irrigation and debridement, placement of an antibiotic spacer and a course of intravenous antibiotics six weeks prior to placement of internal fixation. In these cases, MEF was placed at the time of surgical irrigation and debridement to allow for stability. In those patient’s without an active fixation, both the internal fixation and MEF were placed at the same time. Internal fixation construct was based on surgeon preference. Patients were allowed to transfer weight bear at the time of surgery and could advance as tolerated after 2 weeks. CT was utilized to assess fusion. Outcomes measured were fusion rate and occurrence of internal fixation infection.Results:The mean age of patients was 55 (range 26-75), eight patients had diabetes, three were current smokers, two were former smokers, two patients had open trauma, one patient had peripheral neuropathy and one patient had a history of a non- union with known non-compliance. Six patients had an active infection and underwent irrigation and debridement, placement of antibiotic spacer and MEF during antibiotic treatment. Seven patients underwent intramedullary nail fixation, three patients underwent plate and screw constructs and one patient underwent screw only fixation. CT demonstrated fusion in all patients (100%). The mean time for external fixation was 72 days (range 41-111). There were no cases of infected internal fixation.Conclusion:The findings of the current study suggest high rates of hind foot fusion with the use of internal fixation augmented with MEF in a complex patient group with identified high non-union risk factors. Using internal fixation, patients time in the frame is much reduced than published studies evaluating MEF alone for fusion fixation. MEF did not result in any cases of infected internal fixation. Patients with hybrid fixation also benefit from early weight bearing. We emphasize the importance of good surgical technique and infection management using this technique.

Salmonella enteritis spondylitis of thoracic spine: a case report and review of the literature

BackgroundSpondylitis is a very common back problem in orthopedics, but is rarely caused by Salmonella enteritidis. We herein reported an uncommon case of thoracic spondylitis caused by Salmonella enteritidis.Case presentationA 68-year-old man with high fever was diagnosed as salmonella septicemia initially. His condition was improved after antibacterial treatment. But the symptom of pyrexia was recurred after some days. He was then diagnosed with thoracic spondylitis caused by salmonella enteritidis. After that, he was put on strict antibiotic treatment, and underwent intervertebral lesion debridement, partial rib resection, intervertebral bone fusion and pedicle screw internal fixation. Subsequently, the patient had a significant relief in pain, temperature remained normal, and had no severe complications.ConclusionsSpecial attention should be paid to systemic pain and remain cautious to the occurrence of osteomyelitis in patients with Salmonella septicemia. Moreover, the treatment time for using sensitive antibiotics should be sufficient. Surgical treatment should be considered if strict conservative treatment is failed.

Comparison of anterior and posterior approaches for treatment of traumatic cervical dislocation combined with spinal cord injury: Minimum 10-year follow-up

Anterior reduction and interbody fusion fixation has not been compared directly with posterior reduction and short-segmental pedicle screw fixation for lower cervical dislocation, and so consensus is lacking as to which is the optimal method. The purpose of this paper is to compare long-term outcomes of the anterior versus posterior approach for traumatic cervical dislocation with spinal cord injury. One hundred and fifty-nine patients could be followed for more than 10 years (follow-up rate 84.1%). Ninety-two patients underwent anterior reduction and interbody fusion and fixation, and 67 patients underwent posterior reduction and short-segmental pedicle screw fixation. Japanese Orthopaedic Association (JOA) scores, the Neck Disability Index (NDI), the American Spinal Injury Association grading (ASIA), Odom’s criteria, cervical kyphosis, operative parameters, and surgical or post-operative complications were evaluated. Patients were followed for 10 to 17 years. There was no significant difference in main JOA scores, NDI scores or ASIA scores between the two groups at follow-up. The posterior approach was associated with greater loss of alignment by two years (P = 0.012) and at final follow-up (P < 0.001). The posterior approach group had more blood loss (P < 0.001), longer operation times (P < 0.001), longer hospital stays (P < 0.001) and fewer complications than the anterior approach group. The anterior approach is better than the posterior approach for preserving cervical lordosis, which is associated with a better long-term effect.

Effect of K-line on posterior cervical surgery in patients with posterior longitudinal ligament ossification.

To evaluate the effect of K-line on posterior single-door decompression with fusion fixation (PFF) and posterior single-door decompression with non-fusion fixation (PNF) for patients with ossification of posterior longitudinal ligament (OPLL). A total of 65 patients with OPLL were analyzed retrospectively. They consisted of 44 patients with positive K-line, designated as the K ( +) group, and 21 patients with negative K-line, designated as K (-). The patients were also divided into a PFF group (38 patients) and a PNF group (27 patients). The Japanese Orthopaedic Association (JOA) score, C2-C7 Cobb angle, improvement rate of JOA score, and complications were calculated and statistically analyzed between the groups. In the K ( +) group, there were no significant differences in the incidence of C5 nerve root palsy and C2-C7 Cobb angle between the two groups of surgical patients, but there were significant differences in the improvement rate of JOA score and the incidence of axial pain. In the K (-) group, there were no significant differences in the incidence of axial pain, the incidence of C5 nerve root palsy, and preoperative C2-C7 Cobb angle between the two groups, but significant differences were observed in the improvement rate of JOA score and C2-C7 Cobb angle at the last follow-up. In the K ( +) group, the improvement rate of JOA score was higher and the incidence of axial pain was lesser in the PNF group than in the PFF group. In the K (-) group, the improvement rate of JOA score was higher in the PFF group than in the PNF group, and there was significant loss of C2-C7 Cobb angle in the PNF group.

Rigid transpedicular fixation in the treatment of patients with degenerative lumbar stenosis

A review of modern literature on the issues of rigid transpedicular fixation in patients with degenerative lumbar stenosis is presented. Technical aspects and various options for transpedicular fixation are studied, information on comparing their effectiveness is given. The results of studies evaluating the effectiveness of transpedicular fixation for spinal fusion, pain in the lumbar region, and a violation of the sagittal balance are presented. The complications of transpedicular fixation are highlighted.

RESEARCH ON THE STRATEGY OF REDUCTION OPERATION OF BASILAR INVAGINATION COMBINED WITH ATLANTOAXIAL DISLOCATION

Background: The complicated basilar invagination and atlantoaxial dislocation (BI-AAD) can cause a variety of neurological symptoms. Active treatment should be given. The main method of surgical treatment is to relieve the compression of the ventral bone of the brain stem and to fix the unstable spinal segments for fusion. At present, more surgical methods choose modified posterior cervical reduction and internal fixation fusion. Objective: The clinician has preliminarily designed an internal occipital fixation system capable of restoring both horizontal and vertical AADs, and proposed a new compression and distraction reduction (CDR) technique. The feasibility and effectiveness of posterior AAD reduction surgery using CDR techniques for different types of patients were studied in this paper. Methods: First, according to the CT scan sequence images of the congenital BI-AAD patient’s cervical vertebra, the software Materialize Mimics 13.1 was imported to reconstruct 3D geometric model of cervical spine (C0-C7). Then the geometric topology model was carried out in Geomagic2012 software, and surrounding soft tissue was established using SpaceClaim 14.0. The 3D finite element model (FEM) of cervical vertebra for congenital BI-AAD patients was obtained by assigning material attributes, setting contacts and mesh in ANSYS 14.0. To simulate the physiological activities of the spine under two conditions of forward flexion and backward extension, preoperative verification was carried out with the maximum displacement parameter. According to the postoperative CT data of the patient, the position and degree of freedom (DOF) of the occipitocervical internal fixation system were determined. The FEM of the occipitocervical internal fixation system was established by dividing unit grid in ANSYS. Using multiple loading step of statics analysis method, the CDR technology of posterior AAD reduction surgery was simulated. When the atlantoaxial horizontal and vertical reductions were satisfactory, the displacement data were obtained and verified using the post-operative data. Results: The cervical spine (C0-C7) FEM of congenital BI-AAD patients was established. For some lateral atlantoaxial articulation abnormal ossification II, we simulated the CDR technique for the AAD reduction surgery and proposed using the vertical traction instead of vertical reduction. Conclusion: This study confirms the feasibility and effectiveness of posterior AAD reduction surgery using CDR techniques and proposes the different reduction optimization scheme for the patients with lateral atlantoaxial articulation abnormal ossification II of congenital BI-AAD. The results of this study provide a biomechanical theoretical basis for improving the reliability of simple posterior reduction surgery and optimizing the surgical treatment of BI-AAD.

Pedicle Screw Fixation in Single-Level, Double-Level, or Multilevel Posterior Lumbar Fusion for Osteoporotic Spine: A Retrospective Study with a Minimum 2-Year Follow-Up

Pedicle screw loosening is a common postoperative complication for osteoporotic patients, and several studies have identified the important role of fusion length in internal fixation failure, but the relationship between the number of fusion segments and the potential risks remains unclear. This study aimed to investigate the rate and risk factors of screw loosening in osteoporotic patients with different levels of degenerative lumbar disease. The total cohort of 217 patients was divided into 3 groups according to the different fusion levels: single-level (group A; 100 cases), double-level (group B; 73 cases), and multilevel group (group C; 44 cases). Patient baseline demographic characteristics and assessments with a visual analog scale (VAS) and the Oswestry Disability Index (ODI) before operation and at the last follow-up were compared among the 3 groups. Compared with preoperative values, VAS and ODI scores at the last follow-up were significantly improved in all 3 groups. Operative time, blood loss, length of hospital stay, screw loosening rate, fusion rate, and VAS and ODI scores at the last follow-up obviously increased with the increasing number of fusion segments (group C> group B> group A). Of note, all the screw loosening was observed in cranial and caudal vertebra. Furthermore, multivariate logistic regression analysis identified lumbosacral fixation, larger pelvic incidence (PI)-lumbar lordosis (LL) difference (PT-LL), and greater postoperative pelvic tilt (PT) as independent predictors of screw loosening. However, sex, bone mineral density, body mass index, LL, sacral slope, PI, the change in LL, and preoperative PT were not relevant to screw loosening (P > 0.05). Owing to the high rate of screw loosening in cranial and caudal vertebra, osteoporotic patients with double-level or multilevel pedicle screw fixation benefited less than those with single-level pedicle screw fixation. Larger PI-LL, larger PT, and lumbosacral fixation are other risk factors for screw loosening. An instrument with stronger holding strength at cranial and caudal pedicle screws is recommended for those high-risk patients.

Effect of oblique lateral lumbar intervertebral fusion on inflammatory factors in patients with degenerative spinal canal stenosis

Objective To investigate the effect of oblique lateral lumbar intervertebral fusion (OLIF) on inflammatory factors in patients with degenerative spinal canal stenosis (DLSS). Methods Retrospective analysis of clinical data of 64 DLSS patients in the department of orthopedics, Jizhong Energy Fengfeng Group Hospital from June 2016 to June 2018 was performed. There were 35 males and 34 females, aged (60.70±6.27) years, and the age range was 20 to 80 years. According to the different surgical methods, they were divided into posterior decompression and internal fixation fusion (PLIF) group (n=32) and OLIF group (n=32). The coperation time, intraoperative bleeding volume, postoperative bed rest time, hospitalization time , the back and leg pain visual analogue score (VAS) , Japanese Orthopaedic Association(JOA) score of lumbar vertebrae and serum inflammatory factors [tumor necrosis factor-alpha(TNF-α), interleukin-1alpha(IL-1α), C-reactive protein(CRP)] were observed at preoperative, 3 months and last follow-up. Follow-up using outpatient examination and telephone interview was performed and survial up to March 2019. Measurement data were expressed as mean±standard deviation (Mean±SD), comparison between groups was performed using independent sample t test or analysis of variance of repeated measurement data. Internal comparisons were performed using paired t tests. Count data were expressed as percentage (%), and χ2 test was used. Results There was no significant difference in operation time between OLIF group and PLIF group (P>0.05). In OLIF group, the amount of blood loss (119.72±30.41) mL, bedridden time (2.16±0.35) d and postoperative hospital stay (5.18±2.06) d were significantly lower than that of PLIF group[(318.26±94.62) mL, (3.17±0.54) d, (7.35±1.24) d], the differences between the two groups were statistically significant(P<0.05). All patients were followed for 8 months. The 3 months after operation and last follow-up, the VAS scores of back pain in OLIF group [(1.93±0.54) scores, (1.74±0.63) scores]were significantly lower than that in PLIF group [(4.05±0.62) scores, (3.87±0.74) scores]. The VAS scores of leg pain in OLIF group [(1.56±0.71) scores, (1.37±0.52) scores] were significantly lower than that of PLIF group [(3.74±0.79) scores, (2.53±0.59) scores]. The JOA scores of lumbar vertebrae in PLIF group [(22.57 ±1.83) scores, (24.38±1.65) scores] were significantly higher than that of PLIF group [(20.35±1.78) scores, (22.14±1.35) scores], the differences between the two groups were statistically significant(P<0.05). At 3 months after operation, the levels of serum TNF-α(16.95±3.92) ng/L, IL-1α(9.17±3.78) ng/L and CRP (1.97±0.24) mg/L in OLIF group were significantly lower than those in PLIF group [(20.46 ±4.27) ng/L, (11.51±4.25) ng/L, (2.36±0.32) mg/L]. Last follow-up, the level of serum TNF-α(13.47±3.54) ng/L, IL-1α(6.52±2.09) ng/L and CRP (1.42±0.16) mg/L in the OLIF group were significantly lower than those in the PLIF group [(18.08±3.84) ng/L, (8.73±5.43) ng/L, (2.04±0.25) mg/L], the differences between the two groups were statistically significant (P<0.05). Conclusion Compared with PLIF, OLIF can reduce the amount of intraoperative bleeding, shorten the recovery time, reduce the expression of inflammatory factors and improve the prognosis of patients with DLSS. Key words: Tumor necrosis factor-alpha; Interleukin-1alpha; C-reactive protein; Oblique lateral lumbar interbody fusion; Degenerative lumbar spinal stenosis

Complications of the treatment of post-traumatic deformities of the thoracic and lumbar spine using staged surgical interventions

Objective . To analyze the results of surgical treatment of post-traumatic deformities of the thoracic and lumbar spine using staged surgical interventions from the point of view of surgical safety, and to study the structure, frequency and nature of intra- and postoperative complications and intraoperative blood loss. Material and Methods . A retrospective analysis of data of 212 patients for 2015–2018 was performed. Inclusion criteria were: age over 18 years, staged surgical interventions including anterior spinal fusion and posterior internal fixation performed in one surgical session for post-traumatic deformities of the thoracic and lumbar spine. Patient demographic data and surgical intervention protocols were studied taking into account surgical approaches, duration of operations and blood loss. Intraoperative and postoperative complications up to 6 weeks after surgery were taken into account. Intraoperative blood loss was studied both as the absolute volume and as the percentage of circulating blood volume (CBV). Results . Complications after staged surgical correction of post-traumatic deformities were recorded in 14.2 % of patients, including intraoperative complications in 3.3 % of cases, and postoperative complications in 10.9 %. The most common complications were surgical site infections, usually after posterior approach, and pneumonia. The number of neurological complications was 1.4 %. Complications were more frequent after three-stage surgical interventions than after two-stage ones. The lumbar spine deformity correction was associated with higher complication rate than that in the thoracic spine. Intraoperative blood loss in the study group was 562.2 ± 504.7 ml. The most significant blood loss, over 30 % of the СBV, was noted in 13 (6.1 %) patients. Using of minimally invasive transpedicular fixation during the staged surgical intervention provided the least number of infectious wound complications and the smallest amount of intraoperative blood loss. Conclusion . Staged surgical intervention for the correction of post-traumatic deformity of the thoracic and lumbar spine is a safe method of surgical treatment.

One-stage posterior debridement, bone grafting fusion, and mono-segment vs. short-segment fixation for single-segment lumbar spinal tuberculosis: minimum 5-year follow-up outcomes

BackgroundTo compare the clinical and radiological outcomes between posterior mono-segment and short-segment fixation combined with one-stage posterior debridement and bone grafting fusion in treating single-segment lumbar spinal tuberculosis (LSTB).MethodsSixty-two patients with single-segment LSTB treated by a posterior-only approach were divided into two groups: short-segment fixation (Group A, n = 32) and mono-segment fixation (Group B, n = 30). The clinical and radiographic outcomes were analyzed and compared between the two groups.ResultsThe intraoperative bleeding volume, operation time, and hospitalization duration were lower in Group B than in Group A. All patients achieved the bony fusion criteria. The visual analog scale score, Japanese Orthopedic Association score, and Oswestry Disability Index were substantially improved 3 months postoperatively and at the last visit in both groups, with no significant difference between the two groups (P > 0.05). Kirkaldy–Willis functional evaluation at the final follow-up demonstrated that all patients in both groups achieved excellent or good results. The difference in the angle correction rate and correction loss between Groups A and B was not significant (P > 0.05).ConclusionsOne-stage posterior debridement, bone grafting fusion, and mono-segment or short-segment fixation can provide satisfactory clinical and radiological outcomes. Mono-segment fixation is more suitable for the treatment of single-segment LSTB because the lumbar segments with normal motion can be preserved with less trauma, a shorter operation time, shorter hospitalization, and lower costs.

Interface Fixation Using Absorbable Screws versus Plate Fixation in Anterior Cervical Corpectomy and Fusion for Two-Level Cervical Spondylotic Myelopathy.

BackgroundWe compared the clinical and radiographic outcomes between interface fixation using absorbable screws and plate fixation in anterior cervical corpectomy and fusion (ACCF) to evaluate the effectiveness of these 2 fixation methods for the treatment of 2-level cervical spondylotic myelopathy (CSM).Material/MethodsFrom January 2014 to December 2016, a total of 220 patients who received 2-level ACCF were retrospectively collected. Among them, 108 patients were treated with interface fixation using absorbable screws (Group A) and 112 patients underwent plate fixation (Group B). Japanese Orthopedic Association (JOA) score and Neck Disability Index (NDI) score were employed to compare the clinical improvement. Operative time, blood loss, surgical cost, cervical lordosis, complications, and fusion rate were also evaluated.ResultsThe average follow-up time were 35.2±4.5 months in Group A and 35.9±3.9 months in Group B. There was no difference in operative time and blood loss for both groups. The JOA scores and NDI scores were similar in each follow-up (p>0.05 in all). Group A cost an average of 30% less than Group B for the operation. Both groups achieved 100% in the fusion rate with the same conditions in cervical lordosis. Group A (5/108) had a significantly lower complication rate than Group B (17/112) (p<0.05).ConclusionsACCF with interface fixation using absorbable screws achieved similar clinical outcomes compared to ACCF with plate fixation for 2-level CSM. Moreover, the interface fixation using absorbable screws presented far fewer complications and cost less for the operation.

Pedicle screw instrumentation with or without pelvic fixation in neuromuscular scoliosis: Outcome and complications in a series of 37 patients with a minimum 2-year follow-up

ObjectiveNeuromuscular scoliosis (NMS) is often associated with rapid progressive spinal deformities. Indications, when to extend the instrumentation to the pelvis for pelvic obliquity are not generally accepted at this time. This study reports on the indications, surgical technique and results using pedicle screw instrumentation exclusively with or without pelvic fixation for spine fusion in patients with NMS. Patients and methodsThirty-seven NMS patients were treated with pedicle screw instrumentation (PSI) between 2007 and 2013 with a minimum follow-up of 24 months. The mean age at the time of operation was 14.91 ± 2.03 years (range, 11.17–18.58). Posterior spine fusion (PSF) was conducted in 33 patients; 4 patients underwent a combined anterior spinal release followed by PSF during one-stage surgery. Pelvic fixation was achieved by ilium screws combined with S-1 screws in 4 cases and by sacral-alar-iliac (SAI) technique by Sponseller in 9 cases, respectively. ResultsThe mean primary Cobb angle was 65.5° (range, 14–103°) and improved significantly to 19.8° (range, 1–50°, p < 0.001) after surgery and 20.5° (range, 3–57, p = 0.47) at 2 years FU, respectively. Besides, an improvement of pelvic obliquity and T1 tilt angle could be detected. Major complications occurred in 19% and minor complications in 32%. ConclusionPedicle screw fixation only for spine fusion in patients with NMS can be applied safely with reasonable complication rates. An excellent correction in all planes, a significant improvement of the pelvic obliquity and almost no loss of correction at 2 years FU were observed.

Unilateral Pedicular Screws and Interbody Lumbar Spine Fusion in Unilateral Degenerative Pathology (Technique and Outcome)

Introduction: Lumbar degenerative diseases (LDD) is considered a common disease. Lumbar pedicular screw fixation and interbody fusion is one of the com¬monly used and effective surgical method in management of single-level lumbar degenerative diseases. Although bilateral pedicular screw (PS) fixation after lumbar interbody fusion is accepted as a standard surgical procedure providing rigid fixation with a great biomechanical stability and clinical benefits, the rigidity of bilateral (PS) fixation can cause device-related osteoporosis of the vertebrae which makes the adjacent segment prone to load and motion-induced degeneration. Therefore, the concept of using less rigid systems of fixation has been advocated. Aim of study: To evaluate effectiveness of unilateral pedicular screws fixation and interbody fusion in unilateral degenerative spine pathology. Patients and methods: This study included 34 patients with single level degenerative lumbar spine disease who were subjected to transforaminal interbody lumbar fusion (TILF) and unilateral transpedicular screws fixation between July 2017 and March 2019 in Ain Shams University hospitals. Results: The study was conducted on 34 patients with age ranging between 32-56 years (mean 45.12±7.80 years). There were 17 male and 17 female in this study. When comparing VAS back pain preoperatively and at postoperative intervals of 1,6 and 12 months, it showed highly significant improvement (P-value 0.000). Also when comparing VAS of leg pain preoperatively and at postoperative intervals of 1,6 and 12 months duration, it showed highly significant improvement (P-value 0.000). ODI preoperatively and at postoperative intervals of 1,6 and 12 months showed also highly significant improvement (P-value 0.000). Regarding the fusion rate, at 6 months postoperative 61.8% (21) of the patients had fusion grade 1,26.5% (9) of the patients had fusion grade 2 and 11.8% (4) of the patients had fusion grade 3. While at 12 months postoperative the percent of grade 1 fusion increased to become 85.3% (29 patients) and the rest were grade 2 fusions (14.7%) with no patients with grade 3 fusion. Conclusion: Unilateral pedicular screws and interbody fusion is a good modality of treatment for unilateral degenerative spine pathology.

Unilateral short-segment screw fixation and bone graft fusion for special upper cervical spine injury

Objective To investigate the clinical effect of posterior unilateral short segment screw fixation and bone graft fusion in the treatment of special upper cervical spine injuries. Methods A retrospective case series study was conducted to analyze the clinical data of 15 patients with upper cervical spine injury admitted to Shanxi Bethune Hospital from July 2012 to May 2017. There were nine males and six females, aged 10-69 years [(41.9±20.9)years]. There were eight patients with traumatic atlantoaxial dislocation, one with congenital atlantoaxial dislocation, two with atlantoaxial dislocation with nonunion of odontoid process, three with Anderson type II odontoid process fracture, and one with old odontoid process fracture. All patients had cervico-occipital pain to different degrees, slender unilateral pedicle and distinct stenosis of vertebral artery. All patients were treated with posterior unilateral screw fixation and bone graft fusion. The injury of spinal cord and vertebral artery, operation time and intraoperative blood loss were recorded. Visual analogue scale (VAS) was used to evaluate pain before and after operation, and Japanese Orthopaedic Association (JOA) score was used to evaluate spinal cord function and postoperative improvement rate before and at the last follow-up. The position of internal fixation and fusion of bone graft were observed by X-ray after operation. Results All 15 patients were followed up for 6-36 months [(20.4±8.6)months]. All the screws were implanted successfully at the first time, without spinal cord or vertebral artery injury. The operation time was 100-210 minutes [(131.3±32.0)minutes], and the intraoperative blood loss was 100-450 ml [(203.1±104.0)ml]. Preoperative VAS score was (7.9±0.9)points, and postoperative VAS score was (3.7±0.8)points (P<0.01). Preoperative JOA score was (12.1±4.4)points, and the JOA score at postoperative follow-up was (16.1±1.4)points, with the improvement rate of 68%. Postoperative X-ray showed good recovery of cervical spine sequence. One patient developed loosened internal fixation after the neck brace protection was removed one month after surgery, and the patient recovered after timely second surgical fixation and fusion. The remaining 14 patients did not have loosened internal fixation, fracture or loss of reduction, with bone fusion 6-12 months after surgery. Conclusion Posterior cervical unilateral short-segment screw fixation and bone graft fusion can restore cervical stability, relieve pain, and improve function recovery, which can be used as a complementary procedure to treat upper cervical spine injury with anatomic structure variation. Key words: Cervical vertebrae; Spinal fusion; Surgical procedures, operative

Efficacy comparison between microscope-assisted atlantal pedicle screw placement by hand and drill for unstable atlas burst fracture

Objective To investigate the efficacy of microscope-assisted free-hand atlantal pedicle screw technique for unstable atlas burst fracture. Methods A retrospective case control study was conducted to analyze the clinical data of 48 patients with unstable atlas burst fracture admitted to Ningbo No.6 hospital from January 2016 to June 2018. There were 32 males and 16 females, aged 24-72 years [(49.5±15.2 years)]. A total of 22 patients were treated with the technique of atlas screw placement by drill under microscope (Group A), including 14 males and eight females, aged 24-68 years. Twenty six patients (Group B) were treated with atlantal pedicle screw placement by hand, including 18 males and 8 females, aged 26-72 years [(50.7±15.4 years)]. The operation time, intraoperative blood loss and the times of intraoperative fluoroscopy were compared between the two groups. X-ray and CT were reexamined to evaluate the accuracy of screw placement within one week after operation. The visual analogue score (VAS) and cervical dysfunction index (NDI) were compared before operation and 1 year after operation. The intraoperative complications were recorded. One year after operation, X-ray and CT were reexamined to observe fracture healing, atlantoaxial fusion and failure of internal fixation. Results Group A was followed up for 12-24 months [(18.4±6.8)months], and Group B for 12-24 months [(17.4±7.2)months]. The amount of intraoperative bleeding [(180.5±60.8) ml] and the times of intraoperative fluoroscopy [(1.3±0.8) times] in Group A were significantly lower than those in Group B [(280.1±80.2) ml, (2.2±0.8) times] (P 0.05). There were statistically significant differences in VAS and NDI before operation and one year after operation in both groups (P 0.05). No serious complications such as vertebral artery, nerve root and spinal cord injury occurred. One year follow-up CT showed healed fracture or continuous bone bridge passing through the atlantoaxial intervertebral space. Except for one patient in Group B with lost reduction, other patients had no loosening or fracture of internal fixation. Conclusion Compared with screw placement by hand, the pedicle screw placement by drill under the microscope can reduce the amount of bleeding and the times of fluoroscopy. Key words: Atlanto-occipital joint; Fracture fixation, internal; Pedicle screws

A distraction technique using reduction multi-axial screws for open reduction of high-grade lumbar posterior dislocation:a case report and literature review

BackgroundL3 vertebral fractures with posterior dislocation are rare and usually secondary to high-energy trauma. To assess the outcome of a valuable distraction technique, using long-tail multiaxial pedicle screw which we have employed in reduction of L3 vertebral fracture with posterior dislocation, and emphasize the importance of preoperative blood vessel evaluation.Case presentationA 47-year-old patient fell from a height of 4 m and was paralyzed. Computed tomography scan revealed a three-column ligamentous injury with posterior fracture-dislocation of the L3 vertebral body. Computed tomography angiography showed that the third lumbar artery was ruptured without active bleeding. The patient underwent posterior approach with reduction, transpedicular fixation, and posterolateral fusion with autologous bone graft. Finally, Vertebral reduction and sagittal balance were achieved and patients recovered well after operation.ConclusionPreoperative blood vessel evaluation is very important to avoid massive bleeding during the surgery, and the standard technique which can achieve good reduction is easy to understand, perform, and is reproducible.

Risk Factor Analysis of the Incidence of Subsequent Adjacent Vertebral Fracture After Lumbar Spinal Fusion Surgery with Instrumentation

This study aimed to evaluate the risk factors for adjacent vertebral compression fractures after lumbar spinal fusion with instrumentation. A total of 669 patients who received lumbar instrumented spinal fusion between January 2012 and December 2015 were divided into 2 groups according to whether the adjacent vertebral body was fractured. The covariates recorded were age, sex, bone mineral density, and the number of fixed segments. The anatomic variables were pelvic incidence angle (PI), preoperative lumbar lordosis angle (Pre-LL), postoperative lumbar lordosis angle (Post-LL), Pre-LL minus Post-LL (Loss of LL), postoperative pelvic tilt (Post-PT), postoperative sacral slope, Pre-PI-LL mismatch (Pre-PI minus Pre-LL), and Post-PI-LL mismatch (Post-PI minus Post-LL). A 1-way analysis of variance (ANOVA) was performed with the aforementioned parameters, and binary logistic regression analysis was used to determine the relative risk factors. The 669 patients were followed-up for a mean of 2.7 ± 1.1 years (range, 2-4 years). Twenty-seven patients demonstrated fractures in the adjacent vertebral body after surgery. Analysis by 1-way ANOVA demonstrated that age, PI, Pre-LL, Post-LL, Loss of LL, Post-PI-LL mismatch, Post-PT, and osteoporosis were potential risk factors (all parameters, P< 0.001). Furthermore, binary logistic regression analysis showed that a large Loss of LL, osteoporosis, and old age were also risk factors for adjacent vertebral compression fractures. A greater Loss of LL, osteoporosis, and advanced age may be risk factors for fractures in the adjacent vertebral body of the fixed segment after lumbar fusion fixation.

Rod and Screw Fixation for Cranio-Cervical Instability

Background Data: Atlanto-occipital dislocation is a rare and fatal condition. Pain, limitation of movements, and weakness, were the main complaints of patients with upper cervical lesions. Internal fixation and fusion was indicated in all patients of Atlanto occipital dislocation with deficits. CT scan is the imaging modality of choice for evaluation. Objective: To evaluate the efficacy and safety of rod and screw fixation in cranio-cervical instability. Study Design: Retrospective study reviewed all patient treated by rod and screw fixation, they were 12 patient operated for atlanto-occipital instability from April 2013 to April 2016 in Alazher University Hospital Damietta. Pre and postoperative data collection and analysis of the outcome were completed based on the Frankel classification and grading. Patients and Methods: We operated 12 patients, 10 with traumatic and 2 with pathologically diagnosed Atlanto occipital instability. From April 2013 to April 2016. All patients presented with neck pain, limitation of neck movement, and neurological deficits. The patients were investigated by standard plain X ray to the cervical spine, CT scan and MRI of the cervical spine pre-operatively, and they operated thorough posterior Cranio-cervical fixation. These patients followed post-operatively clinically for improving neural functions and radiologically for alignment, stability, fusion and efficacy of hard ware fixation. Results: The mean age of the studied cases was 42.1 years, trauma was the cause of instability in 10 patients, and 2 patients one with rheumatoid arthritis and one with neoplastic lesion. The mean follows up period is 14.7 months. We used screw rod system in posterior craniocervical fixation with iliac bone graft without operative or post-operative complications. All our patients were improved neurologically post-operatively and no hardware failure during the follow up period. Conclusion: Craniocervical instability was rare condition, with miss diagnosis and may be fatal condition. Posterior occipitocervical fixation when indicated can be done by various techniques. The screw rod system was the most upgraded used technique with immediate rigid fixation. Surgery in this area was possible with confident results.

Efficacy comparison of posterior atlantoaxial screw-rod fixation combined with spinous process muscle-vessel complex bone graft or iliac bone graft for atlantoaxial instability

Objective To compare the clinical efficacy of posterior atlantoaxial screw-rod fixation combined with spinous process muscle-vessel complex bone graft or iliac bone graft for atlantoaxial instability. Methods A retrospective case-control study was conducted to analyze the clinical data of 56 patients with atlantoaxial instability admitted to the Sixth Hospital of Ningbo from September 2014 to October 2016. There were 35 males and 21 females, with the age range from 9 to 59 years [(50.3±3.2)years]. A total of 26 patients were treated with posterior atlantoaxial screw-rod fixation combined with spinous process muscle-vessel complex bone graft (complex group), while 30 patients were treated with iliac bone graft (ilium group). Patients showed different degrees of neck pain and limited neck activity preoperatively. X-ray films and three-dimensional CT examination of the cervical spine were taken before and after operation for evaluating the atlantoaxial reduction, bone graft fusion and internal fixation. The operation time, intraoperative bleeding, bone fusion time, visual analogue scale (VAS), Japanese Orthopaedic Association (JOA) score, atlantodental interval (ADI) and axial symptoms were compared between the two groups, and the complications were recorded. Results Both groups were followed up for 24-30 months, with an average of 27.4 months. In the complex group and the ilium group, the operation time was (2.21±0.25)hours and (2.72±0.26)hours (P 0.05), respectively. In the complex group, the VAS was (5.45±0.69)points before operation, (2.64±0.51)points at the follow-up one month after operation, (0.91±0.7)points at the follow-up 12 months after operation, and (0.45±0.16)points at the follow-up 24 months after operation; and in the ilium group, the VAS was (5.18±0.75)points, (2.45±0.52)points, (1.27±0.19)points and (0.41±0.18)points correspondingly. In terms of VAS, there were significant differences before and after operation within each group (P 0.05). In the complex group, the JOA score was (10.82±0.35)points before operation, (12.73±0.65)points at the follow-up one month after operation, (15.18±0.61)points at the follow-up 12 months after operation, and (15.64±0.15)points at the follow-up 24 months after operation; and in the ilium group, the JOA score was (10.73±1.19)points, (13.01±0.63)points, (14.73±0.91)points and (15.55±0.51)points correspondingly. In terms of JOA score, there were significant differences between before and after operation within each group (P 0.05). In the complex group, the ADI was (2.28±0.59)mm before operation, (1.83±0.56)mm at the follow-up one month after operation, (1.71±0.56)mm at the follow-up 12 months after operation, and (1.59±0.67)mm at the follow-up 24 months after operation; and in the ilium group, the ADI was (2.23±0.60)mm, (1.80±0.18)mm, (1.67±0.69)mm and (1.62±0.53)mm correspondingly. In terms of ADI, there were significant differences between before and after operation within each group (P 0.05). The axial symptom scores were graded as excellent in 23 patients and good in three patients of the complex group while excellent in 21 patients and good in nine patients in the ilium group (P>0.05). There were no patients with spinal nerve injury caused by pedicle screw placement after operation. One patient in the ilium group had incision errhysis and recovered after dressing change, and other patients had no incision infection. Conclusions For atlantoaxial instability, posterior atlantoaxial screw-rod fixation combined with spinous process muscle-vessel complex bone graft or autogenous iliac bone graft can both achieve satisfactory clinical results. The spinous process-muscle-vascellum complex graft has less operation time and intraoperative bleeding than the autogenous iliac bone graft, which can be a feasible alternative operation. Key words: Spinal fractures; Bone transplantation; Fracture fixation, internal