west china medical publishers
Keyword
  • Title
  • Author
  • Keyword
  • Abstract
Advance search
Advance search

Search

find Keyword "screw fixation" 11 results
  • SURGICAL TREATMENT OF DISCOGENIC LOW BACK PAIN BY MINIMALLY INVASIVE TRANSFORAMINAL LUMBAR INTERBODY FUSION COMBINED WITH UNILATERAL PEDICLE SCREW FIXATION

    【Abstract】 Objective To investigate the effectiveness of surgical treatment for discogenic low back pain (DLBP) by minimally invasive transforaminal lumbar interbody fusion (TLIF) combined with unilateral pedicle screw fixation (UPSF). Methods Between March 2006 and July 2009, 57 patients with single-level DLBP were treated by minimally invasive TLIF combined with UPSF, including 27 males and 30 females with an average age of 45.6 years (range, 38-61 years) and a disease duration of 3.8 years (range, 9 months to 11 years). The involved segments included L2,3 in 2 cases, L3,4 in 5 cases, L4,5 in 29 cases, and L5, S1 in 21 cases. The operative time, incision length, intraoperative blood loss, postoperative drainage volume, hospitalization times, fusion rate, and complications were observed. The effectiveness were evaluated through Oswestry disability index (ODI) and visual analogue score (VAS), and the operative outcomes were compared in different groups classified according to various pressures of the contrast medium and sensitivities to discoblock after inducing consistent pain. Results The operation time, incision length, blood loss, postoperative drainage volume, and hospitalization times were (84.6 ± 37.4) minutes, (3.4 ± 0.6) cm, (132.5 ± 23.2) mL, (58.7 ± 21.4) mL, and (6.5 ± 0.8) days, respectively. All patients were followed up 2 years and 2 months to 5 years and 4 months (mean, 3.2 years). At last follow-up, ODI and VAS scores were significantly improved when compared with preoperative scores (P lt; 0.05). The effectiveness according to ODI were excellent in 27 cases, good in 22 cases, fair in 6 cases, and poor in 2 cases, with an excellent and good rate of 86.0%. All patients acquired b interbody fusion. At last follow-up according to ODI and VAS scores, better results were found in patients of low-pressure sensitive group and high-sensitive discoblock group (P lt; 0.05). Conclusion Minimally invasive TLIF combined with UPSF is reliable for DLBP with minimal surgical trauma, less paravertebral tissue injury, and fewer complications, but the indications for operation must be strictly followed. Patients being sensitive to low-pressure or high-sensitive to discoblock can achieve better surgical results.

    Release date:2016-08-31 04:22 Export PDF Favorites Scan
  • ANATOMIC STUDY ON PERCUTANEOUS ANTERIOR TRANSARTICULAR SCREW FIXATION BY CT THREEDIMENSIONAL IMAGING

    Objective To improve the safety of the percutaneous anterior transarticular screw fixation (PATSF) by measuring the parameters related to PATSF. Methods Spiral CT scan and three-dimensional reconstructions of the atlantoaxis were performed in 50 adult volunteers. The section of inner margin of atlantal superior articular facet, the coronal plane ofvertebral artery cavity, and the sagittal plane of atlano-axis were obtained with multiplanar reconstruction on hel ical CT. The atlantoaxial vertebral structure and the direction of vertebral artery cavity were observed. The parameters related to PATSF were measured and analysed. Results The suitable position of screw insertion was 4.0 mm from the midpoint of the axoidean anteroinferior margin. The maximum external angle of PATSF was (29.89 ± 1.41)°; the minimum external angle was (4.37±0.87)°; the maximum backward angle was (32.41 ± 1.66)°; the optimal external angle was (17.13 ± 0.88)°; the optimal backward angle was (17.62 ± 1.03)°; and the optimal screw length was (41.57±0.79) mm. The atlantoaxial articular facial diameter was (16.71 ± 1.61) mm; the maximum distance of atlantal lateral displacement was (6.96 ± 1.09) mm; and the ratio of them was 41.80% ± 5.69%. Conclusion The optimal insertion of PATSF is safe and rel iable. The screw can be inserted when the displacement of the atlantal lateral mass is in a certain degree.

    Release date:2016-08-31 05:42 Export PDF Favorites Scan
  • PEDICLE SCREW FIXATION AND ALLOGRAFT BONE IN POSTERIOR SPINAL FUSION FOR TREATMENT OF THORACOLUMBAR VERTEBRAL FRACTURES/

    Objective To investigate the efficacy of the pedicle screw fixation and allograft bone in posterior spinal fusion for the treatment of thoracolumbar vertebral fractures. Methods From September 2006 to March 2008, 105 cases of thoracolumbar vertebral fractures were treated with allograft bone in posterior spinal fusion after the pedicle screw fixation,including 75 males and 30 males aged 15-65 years (mean 37 years). The mixture which consisted of spinous process and vertebral plate sclerotin and homogeneity variant bone was used as bone graft to implant into articular process and processus transversus space or vertebral plate space. The time from injury to surgery varied from 8 hours to 21 days, with an average of 3 days. There were 52 cases of fall ing injuries from height, 35 cases of traffic accident injuries, 11 cases of bruise injuries and 7 cases of tumbl ing injuries. Before operation, the primary cl inical symptoms of patients included local pain combined with l imitation of activity, 30 cases compl icated by various degrees of spinal cord and nerve root functional disturbance. According to Mcaffee classification, there were 7 cases of flexion depressed fractures, 86 cases of blow-out fractures, 9 cases of Chance fractures and 3 cases of dislocation-fracture. According to Frankel grade, there were 11 cases of grade A, 2 cases of grade B, 7 cases of grade C, 10 cases of grade D and 75 cases of grade E. The X-ray examination of all patients denoted that the bodies of injuryed vertebra were compressed and wedge-shaped, and the CT scan showed that 98 cases had spinal stenosis. After 2 weeeks and 3, 6, 12 months, the X-ray films were taken to evaluate bone graft fusion. The Cobb angle was measured. The recovery of nerve function was analyzed. Results The operation time was 55-180 minutes (mean 90 minutes) and the blood loss was 100-900 mL (mean 200 mL). All patients achieved heal ing by first intention with no compl ication. After operation, 93 cases were followed up for 6-15 months with an average of 11 months. Except for 11 patients who were at grade A before operation, one to two grade recover was observed in other patients. The average Cobb angle of injury segment was improved from preoperative 32.1° to postoperative 5.2°. The height of anterior border of injuried vertebral body was recovered from the preoperative average compressed remaining height 61.5% to postoperative 96.8%. The vestigial degree of canal is spinal is anteroposterior diameter was recovered from preoperative 65.7% to postoperative 89.9%. Imageology examination showed that all the patient achieved bone union within 6 months. The fusion rate of bone graft in spinal fusion was 100%. No loosening and breaking of nails occurred. Conclusion Pedicle fixators can restore and fix the thoracolumbar fractures, and the combination of autograft and allograft bone transplantation is a safe, rel iable and effective method.

    Release date:2016-09-01 09:06 Export PDF Favorites Scan
  • TREATMENT OF DEGENERATIVE LUMBAR SPINE INSTABILITY WITH TRANSPEDICAL SCREW FIXATION AND INTERTRANSVERSE PROCESS AUTOGENOUS BONE GRAFTING

    OBJECTIVE: To observe the early clinical results with degenerative lumbar instability treated with transpedical screw fixation and intertransverse process autogenous bone grafting. METHODS: From September 2000 to February 2002, 19 patients (5 males and 14 females) of degenerative lumbar spine instability were treated with decompression for spinal canal stenosis, transpedical screw fixation and intertransverse process autogenous bone grafting. The locations of degenerative lumbar spine instability were between L4 and L5 in 10 patients, between L3, L4 and L5 in 4 cases, between L3 and L4 in 3 cases, between L5 and S1 in 2 cases. The results were evaluated after operation. The preoperative clinical symptoms disappeared completely as excellent results, relieved obviously as good results, improved as fair results and unrelieved or worsened as poor results. RESULTS: Seventeen patients were followed up for 4-18 months with an average of 8.1 months. The results of the treatment were excellent in 12 patients, good in 4 patients and fair in 1 patient. The excellent and good rate was 94.1%. Intertransverse process arthrodesis was obtained after 6 months of operation in all cases. No loosened and broken instruments occurred. CONCLUSION: The advantages of degenerative lumbar spine instability treated with transpedical screw fixation and intertransverse are reliable fixation, high successful rate of fusion and less influence on spinal canal. The above results show satisfactory clinical outcome.

    Release date:2016-09-01 09:35 Export PDF Favorites Scan
  • SECURITY OF FRACTURED VERTEBRAL PEDICLE SCREW IN DIFFERENT TYPES OF PEDICLE FRACTURES

    ObjectiveTo investigate the security of pedicle screw fixation in fractured vertebra in treatment of thoracolumbar fractures by comparing with routine fixation cross fractured vertebra. MethodsA total of 101 cases of single segmental thoracolumbar fracture were selected between June 2008 and June 2011. Of them, 56 cases underwent pedicle screw fixation in fractured vertebra (group A), and 45 cases received routine fixation cross fractured vertebra (group B). There was no significant difference in gender, age, causes of injury, fracture type, fracture segment, Frankel grading, time of injury to operation, and the preoperative anterior vertebral height compression ratio and the canal occupation rate between 2 groups (P>0.05). There were 34 cases of junction fracture of pedicle and vertebra (type I), 2 cases of pedicle waist fracture (type Ⅱ), and 20 cases of junction fracture of pedicle and lamina (type Ⅲ) in group A. The position of fractured vertebral pedicle screw was observed; the anterior vertebral height compression ratio, canal occupation rate, and surgical complications were compared between 2 groups. ResultsA total of 103 pedicle screws were placed in 54 patients of group A, except 2 patients of type Ⅱ fracture; 96 screws were placed in the bone cortex completely and 7 screws deviated. The operation time of group A was significantly longer than that of group B (t=4.339, P=0.000), but there was no significant difference in intraoperative blood loss between 2 groups (t=-0.089, P=0.929). All 101 patients were followed up 6-16 months (mean, 8.5 months). The patients of 2 groups achieved nerve functional recovery. Fixation-related complications occurred in 1 case of 2 groups respectively, showing no significant difference (P=1.000). At last follow-up, according to Denis lumbago classification, 51 cases were rated as P1 level and 5 cases as P2 level in group A; 35 cases were rated as P1 level, 8 cases as P2 level, and 2 cases as P3 level in group B; and there was no significant difference between 2 groups (Z=-1.836, P=0.066). There was no significant difference between 2 groups in canal occupation rate at immediate after operation and at last follow-up (P>0.05), and in the anterior vertebral height compression ratio at immediate after operation (P>0.05), but the anterior vertebral height compression ratio of group B was significantly higher that of group A at last follow-up (P<0.05). ConclusionSingle segmental thoracolumbar fracture treated by pedicle screw fixation in fractured vertebra through posterior approach is safe and feasible according to different pedicle fracture types to guide fixation.

    Release date: Export PDF Favorites Scan
  • MINIMALLY INVASIVE PASSAGE IN POSTERIOR LAMINOTOMY DECOMPRESSION AND INTERVERTEBRAL BONE GRAFTING COMBINED WITH PERCUTANEOUS PEDICLE SCREW FIXATION FOR TREATMENT OF Denis TYPE B THORACOLUMBAR BURST FRACTURES

    ObjectiveTo evaluate the feasibility and the effectiveness of minimally invasive passage in posterior laminotomy decompression and intervertebral bone grafting combined with percutaneous pedicle screw fixation for the treatment of Denis type B thoracolumbar burst fractures. MethodsBetween January 2013 and March 2015, 53 patients with Denis type B thoracolumbar burst fractures were treated by minimally invasive passage in posterior laminotomy decompression and intervertebral bone grafting combined with percutaneous pedicle screw fixation. There were 37 males and 16 females with a mean age of 43 years (range, 16-57 years). The causes included falling injury from height in 23 cases, traffic accident injury in 15 cases, heavy pound injury in 7 cases, and falling injury in 8 cases. The time between injury and operation was 7 hours to 12 days (mean, 6.7 days). The involved segments included T11 in 2 cases, T12 in 7 cases, L1 in 20 cases, L2 in 18 cases, and L3 in 6 cases; based on the neurological classification of spinal cord injury by American Spinal Injury Association (ASIA), 3 cases were rated as grade A, 5 cases as grade B, 12 cases as grade C, 24 cases as grade D, and 9 cases as grade E. The operation time, bleeding volume, and postoperative drainage were recorded; postoperative visual analogue scale (VAS) was used for pain evaluation, and ASIA for neurological function assessment; CT and X-ray films were taken to observe fracture healing, bone fusion, and grafted bone absorption; The vertebral canal patency rate was calculated; the relative height of fractured vertebrae and Cobb angle were measured. ResultsThe operation was successfully completed in all patients; the average operation time was 150 minutes (range, 90-240 minutes); the average bleeding volume was 350 mL (range, 50-500 mL); the average postoperative drainage was 80 mL (range, 20-150 mL); and the average VAS score was 2.3 (range, 1.5-4.7) at 3 days after operation. The incisions healed primarily. All the patients were followed up 12-19 months (mean, 15 months). All fractures healed at 3-9 months (mean, 6 months). No complications of broken nails, broken rod, and screw loosening occurred. At last follow-up, the vertebral canal patency rate was significantly improved when compared with preoperative value (t=27.395, P=0.000). The Cobb angle, and the anterior and posterior heights of of traumatic vertebra were significantly improved at 1 week, 1 year, and last follow-up when compared with preoperative ones (P < 0.05), but there was no significant difference between different time points after operation (P > 0.05). The neurological function was improved in different degrees; 1 case was rated as grade A, 4 cases as grade B, 7 cases as grade C, 15 cases as grade D, and 26 cases as grade E, showing significant difference when compared with preoperative one (Z=-5.477, P=0.000). ConclusionMinimally invasive passage in posterior laminotomy decompression, bone graft in the injured vertebrae combined with percutaneous pedicle screw fixation is an effective method to treat Denis type B thoracolumbar burst fractures, which not only can fully decompression, but also can effectively maintain the postoperative injured vertebral height, reduce the postoperative failure risk of internal fixation and decrease operation trauma.

    Release date: Export PDF Favorites Scan
  • POSTERIOR ATLANTOAXIAL LATERAL MASS SCREW FIXATION AND SUBOCCIPITAL DECOMPRESSION FOR TREATMENT OF Arnold-Chiari MALFORMATION ASSOCIATED WITH ATLANTOAXIAL DISLOCATION

    ObjectiveTo evaluate the effectiveness of the posterior atlantoaxial lateral mass screw fixation and suboccipital decompression in the treatment of Arnold-Chiari malformation associated with atlantoaxial joint dislocation. MethodsBetween September 2012 and November 2015, 17 cases of Arnold-Chiari malformation associated with atlantoaxial dislocation were treated by the posterior atlantoaxial lateral mass screw fixation and suboccipital decompression and expansion to repair the dura mater and bone graft fusion. There were 10 males and 7 females, aged 35-65 years (mean, 51.4 years). The disease duration was 14 months to 15 years with an average of 7.4 years. According to Arnold-Chiari malformation classification, 13 cases were rated as type I, 3 cases as type II, and 1 case as type III-IV. Cervical nerve root stimulation and compression symptoms were observed in 12 cases, occipital foramen syndrome in 11 cases, cerebellar compression symptoms in 6 cases, and syringomyelia in 10 cases. ResultsPrimary healing of incision was obtained in the other patients except 1 patient who had postoperative cerebrospinal fluid leakage after removal of drainage tube at 3 days after operation, which was cured after 7 days. All patients were followed up 6 months to 2 years, with an average of 18.4 months. The neurological dysfunction was improved in different degrees after operation. The Japanese Orthopedic Association (JOA) score was significantly increased to 16.12±1.11 at 6 months from preoperative 11.76±2.01 (t=13.596, P=0.000); compression of spinal cord and medulla was improved. X-ray examination showed bone graft fusion at 6 months after operation. In 10 patients with spinal cord cavity, MRI showed empty disappearance in 3 cases, empty cavity lessening in 6 cases, and no obvious change in 1 case at 6 months. ConclusionAtlantoaxial lateral mass screw fixation and suboccipital decompression and expansion to repair the dura mater can obtain good effectiveness in the treatment of Arnold Chiari malformation associated with atlantoaxial transarticular dislocation.

    Release date:2016-11-14 11:23 Export PDF Favorites Scan
  • Effectiveness of F-shaped screw fixation technique in treatment of Pauwels type Ⅲ femoral neck fractures

    Objective To summarize the effectiveness of F-shaped screw fixation technique in treatment of Pauwels type Ⅲ femoral neck fractures. Methods Between January 2013 and December 2016, 43 patients with Pauwels type Ⅲ femoral neck fractures were treated with F-shaped screw fixation technique. There were 32 males and 11 females with an average age of 38.9 years (range, 20-55 years). The fractures located on the left side in 21 patients and on the right side in 22 patients. The cause of injury included traffic accident in 19 patients and falling from height in 24 patients. There were 25 patients of Garden type Ⅲ and 18 of Garden type Ⅳ. The time from injury to operation was 2-3 days (mean, 2.2 days). These data were recorded, including operative time, fluoroscopy time, postoperative hospital stay, quality of reduction, postoperative complications (nonunion, varus deformity, femoral neck shortening, avascular necrosis of femoral head, screws back-out), and Harris scores. Results The operative time was 28-45 minutes (mean, 37.5 minutes). The fluoroscopy time was 13-20 seconds (mean, 14.7 seconds). The postoperative hospital stay was 2-3 days (mean, 2.7 days). All incisions healed by first intention. All patients were followed up 18–58 months with an average of 38.7 months. All patients have anatomical reduction of fractures. Fracture healing occurred in 42 patients; the union time was 3-5 months with an average of 3.6 months. Nonunion occurred in 1 patient who was treated with total hip arthroplasty. Of the 42 patients with fracture healing, 11 cases had a femoral neck shortening, 9 cases had varus deformity, 3 cases had avascular necrosis of femoral head, and 8 cases had screws back-out. There was no significant difference in complication incidences between Garden type Ⅲ fractures and Garden type Ⅳ fractures (P>0.05). Conclusion Treatment of femoral neck fractures by using the F-shaped screw fixation technique, can achieve satisfactory effectiveness with less postoperative complication.

    Release date:2018-10-31 09:22 Export PDF Favorites Scan
  • Biomechanical comparative analysis of screw fixation and cortical endo-button fixation in Latarjet procedure for anterior dislocation of shoulder joint

    ObjectiveTo clarify the value of the cortical endo-button as an internal fixator in Latarjet procedure through biomechanical analysis.MethodsTen pairs of shoulder joints from 6-7 months old male pigs were selected. Each pair was randomly divided into screw group and endo-button group. A 25% glenoid defect model was created, and the porcine infraspinatus tendon and its associated bone were used to simulate conjoint tendon and coracoid process in human body. The bone grafts were fixed with two 3.5 mm screws and double cortical endo-buttons with high-strength sutures in screw group and endo-button group, respectively. The prepared glenoid defect model was fixed on a biomechanical test bench and optical markers were fixed on the glenoid and the bone block, respectively. Then fatigue test was performed to observe whether the graft or internal fixator would failed. During the test, the standard deviations of the relative displacement between the graft and the glenoid of two groups were measured by optical motion measure system for comparison. Finally the maximum failure load comparison was conducted and the maximum failure loads of the two groups were measured and compared.ResultsThere was no tendon tear, bone fracture, and other graft or internal fixation failure in the two groups during the fatigue test. The standard deviation of the relative displacement of the screw group was (0.007 87±0.001 44) mm, and that of the endo-button group was (0.034 88±0.011 10) mm, showing significant difference between the two groups (t=7.682, P=0.000). The maximum failure load was (265±39) N in screw group and (275±52) N in endo-button group, showing no significant difference between the two groups (t=1.386, P=0.199). There were 3 ways of failure: rupture at bone graft’s tunnel (6/10 from screw group, 3/10 from endo-button group), tendon tear at the cramp (2/10 from screw group, 2/10 from endo-button group), and tendon tear at the internal fixator interface (2/10 from screw group, 5/10 from endo-button group), showing no significant difference between the two groups (P=0.395).ConclusionAlthough the endo-button fixation fails to achieve the same strong fixation stability as the screw fixation, its fixation stability can achieve the clinical requirements. The two fixation methods can provide similar fixation strength when being used in Latarjet procedure.

    Release date:2020-06-15 02:43 Export PDF Favorites Scan
  • Effect of percutaneous pedicle screw fixation on the reduction of thoraculumbar burst fractures with posterosuperior fracture fragment

    Objective To explore the effectiveness of percutaneous pedicle screw fixation on the indirect reduction of posterosuperior fracture fragment in the thoraculumbar burst fractures. Methods Patients with thoracolumbar fractures treated in the Fourth People’s Hospital of Zigong from September 2017 to September 2019 were collected retrospectively. All patients were treated with percutaneous pedicle screw fixation. The main observation indexes before operation, 3 days after operation and 1 year after operation were compared, including the height ratio of the anterior margin of fractured vertebra, the inversion angle of posterosuperior fracture fragment, the fragment displacement, the occupancy rate of spinal canal, the Cobb angle of kyphosisat, Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI). Results A total of 38 patients were included. All patients were followed up for more than 1 year. During the follow-up period, there were no complications such as nerve injury, incision infection, internal fixation loosening or fracture. The operation time was (91.7±10.4) min, the amount of intraoperative bleeding was (94.3±19.5) mL, and the length of surgical incision was (9.3±1.8) cm. The height ratio of the anterior margin of fractured vertebra, the inversion angle of posterosuperior fracture fragment, the fragment displacement, the occupancy rate of spinal canal, the Cobb angle of kyphosisat 3 days after operation were significantly improved compared with those before operation (P<0.05); the height ratio of the anterior margin of fractured vertebra, the occupancy rate of spinal canal, and the Cobb angle of kyphosisat 1 year after operation were also significantly improved compared with those before operation (P<0.05); the height ratio of the anterior margin of fractured vertebra and the occupancy rate of spinal canalat 1 year after operation were significantly improved than those 3 days after operation (P<0.05), but the Cobb angle of kyphosis 1 year after operation was significantly lost than that 3 days after operation (P<0.05). The VAS score and ODI index 3 days and 1 year after operation were significantly improved compared with those before operation (P<0.05), and the VAS score and ODI index 1 year after operation were improved compared with those 3 days after operation (P<0.05). Conclusion The percutaneous pedicle screw fixation can effectively reduce the retropulsed bone fragment indirectly and restore the Cobb angle of kyphosis of the thoraculumbar burst fractures without neurological deficit, and at the same time reduce the operation time and surgical trauma.

    Release date: Export PDF Favorites Scan
2 pages Previous 1 2 Next

Format

Content