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.
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.
Objective To explore the effectiveness of the percutaneous parallel screw fixation via the posterolateral “safe zone” for Hawkins type Ⅰ-Ⅲ talar neck fractures. Methods A retrospective analysis was conducted on the clinical data from 35 patients who met the selection criteria of talar neck fractures between January 2019 and June 2021. According to the surgical method, they were divided into a study group (14 cases, using percutaneous posterolateral “safe zone” parallel screw fixation) and a control group (21 cases, using traditional open reduction and anterior cross screw internal fixation). There was no significant difference in gender, age, affected side, Hawkins classification, and time from injury to operation between the two groups (P>0.05). The operation time, bone healing time, complications, and Hawkins sign were recorded, and the improvement of pain and ankle-foot function were evaluated by visual analogue scale (VAS) score and American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot score at last follow-up. The overall quality of life was assessed by the short form of 12-item health survey (SF-12), which was divided into physical and psychological scores; and the satisfaction of patients was evaluated by the 5-point Likert scale. Results The operation time in the study group was significantly shorter than that in the control group (P<0.05). All patients werefollowed up 13-35 months, with an average of 20.6 months; there was no significant difference in the follow-up time between the two groups (P>0.05). The time of bone healing in the study group was shorter than that in the control group, and the positive rate of Hawkins sign (83.33%) was higher than that in the control group (33.33%), and the differences were significant (P<0.05). In the control group, there were 2 cases of incision delayed healing, 7 cases of avascular necrosis of bone, 3 cases of joint degeneration, 1 case of bone nonunion, and 3 cases of internal fixation irritation; while in the study group, there were only 2 cases of joint degeneration, and there was a significant difference in the incidence of complications between the two groups (P<0.05). At last follow-up, there was no significant difference in VAS score between the two groups (P>0.05), but the SF-12 physical and psychological scores, AOFAS ankle and hindfoot scores, and patients’ satisfaction in the study group were significantly better than those in the control group (P<0.05). ConclusionThe treatment of Hawkins type Ⅰ-Ⅲ talar neck fractures with percutaneous parallel screw fixation via the posterolateral “safe zone” can achieve better effectiveness than traditional open surgery, with the advantages of less trauma, fewer complications, faster recovery, and higher patient satisfaction.
Objective To investigate ideal screw implant angle in reconstruction of tibiofibular syndesmosis injury by using a biomechanical test. Methods A total of 24 ankle specimens from adult cadavers were used as the tibiofibular syndesmosis injury model. According to the angle of screw placement, the tibiofibular syndesmosis injury models were randomly divided into groups A (0°), B (10°-15°), C (20°-25°), and D (30°-35°), and the screws were placed at a level 2 cm proximal to the ankle joint. The displacement of fibula was measured by biomechanical testing machine at neutral, dorsiflexion (10°), plantar flexion (15°), varus (10°), and valgus (15°) positions, with axial load of 0-700 N (pressure separation test). The displacement of fibula was also measured at neutral position by applying 0-5 N·m torque load during internal and external rotation (torsional separation test). Results In the pressure separation test, group C exhibited the smallest displacement under different positions and load conditions. At neutral position, significant differences were observed (P<0.05) between group A and group C under load of 300-700 N, as well as between group B and group C under all load conditions. At dorsiflexion position, significant differences were observed (P<0.05) between group A and group C under load of 500-700 N, as well as between groups B, D and group C under all load conditions, and the displacements under all load conditions were significantly smaller in group A than in group B (P<0.05). At plantar flexion position, significant differences were observed (P<0.05) between group D and group C under all load conditions. At valgus position, significant differences were observed (P<0.05) between group A and group C under load of 400-700 N, as well as between groups B, D and group C under all load conditions. In the torsional separation test, group C exhibited the smallest displacement and group B had the largest displacement under different load conditions. During internal rotation, significant differences were observed (P<0.05) between group B and group C under all load conditions, as well as between group D and group C at load of 3-5 N·m. During external rotation, significant differences were observed between groups B, D and group C under all load conditions (P<0.05). No significant difference was detected between groups at the remaining load conditions (P>0.05). ConclusionThe ideal screw implant angle in reconstruction of tibiofibular syndesmosis injury was 20°-25°, which has a small displacement of fibula.
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.
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.
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.
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.
Objective To compare the effectiveness of percutaneous short-segment injured vertebra pedicle screw fixation combined with bone grafting versus percutaneous short-segment injured vertebra pedicle screw fixation alone for the treatment of thoracolumbar fractures. Methods The clinical data of 54 patients with single-level thoracolumbar fractures who met the selection criteria between January 2023 and February 2024 were retrospectively analysed. Based on whether bone grafting was performed on the injured vertebra, the patients were divided into a control group (28 cases, percutaneous short-segment injured vertebra pedicle screw fixation alone) and a study group (26 cases, percutaneous short-segment injured vertebra pedicle screw fixation combined with bone grafting using a self-made minimally invasive bone grafting funnel). No significant difference was observed between the two groups (P>0.05) in baseline data, including age, gender, surgical segment, cause of injury, AO classification, and preoperative anterior-vertebral height compression ratio, mid-vertebral height compression ratio, Cobb angle, visual analogue scale (VAS) score, and Oswestry Disability Index (ODI). The operation time, intraoperative blood loss, fracture healing status, removal time of internal fixator, and complications were recorded and compared between the two groups. Effectiveness was assessed using anterior-vertebral height compression ratio, mid-vertebral height compression ratio, Cobb angle, VAS scores, and ODI taken preoperatively, at 1 week postoperatively, and at last follow-up. ResultsAll patients in both groups successfully underwent surgery. The operation time and intraoperative blood loss in the control group were significantly less than those in the study group (P<0.05). No significant difference was observed in the follow-up time between the study group [(14.46±2.00) months] and control group [(14.36±1.83) months] (P>0.05). The fracture healing time of the study group was significantly shorter than that of the control group (P<0.05). One patient in the study group was found to have bilateral titanium rod breakage by X-ray reexamination at 8 months after operation, and there was no subsequent vertebral height collapse occurred, and the internal fixator was removed following complete fracture healing. The other patients had no complication such as spinal cord injury, internal fixator loosening and breakage. There was no significant difference in the removal time of internal fixator between the two groups (P<0.05). The anterior-vertebral height compression ratio, mid-vertebral height compression ratio, Cobb angle, VAS score, and ODI significantly improved in both groups at 1 week after operation and at last follow-up (P<0.05). Among them, the VAS score, and ODI further improved at last follow-up when compared with at 1 week after operation, Cobb angle lost a little at 1 week after operation, while anterior-vertebral height compression ratio and mid-vertebral height compression ratio slightly increased when compared with 1 week after operation, and the differences were significant (P<0.05). There was no significant difference between the two groups in Cobb angle at last follow-up, VAS score and ODI at 1 week after operation (P>0.05), while the other indicators in the study group were significantly better than those in the control group at all time points (P<0.05). Conclusion Compared to percutaneous short-segment injured vertebra pedicle screw fixation alone, the technique combined with intravertebral bone grafting can shorten fracture healing time, effectively restore and maintain vertebral body height, correct kyphotic deformity, and improve clinical outcomes for patients with thoracolumbar fractures.
Objective To investigate the effectiveness of Holosight robotic navigation-assisted percutaneous cannulated screw fixation for femoral neck fractures. Methods A retrospective analysis was conducted on 65 patients with femoral neck fractures treated with cannulated screw fixation between January 2022 and February 2024. Among them, 31 patients underwent robotic navigation-assisted screw placement (navigation group), while 34 underwent conventional freehand percutaneous screw fixation (freehand group). Baseline characteristics, including age, gender, fracture side, injury mechanism, Garden classification, Pauwels classification, and time from injury to operation, showed no significant differences between the two groups (P>0.05). The operation time, intraoperative blood loss, fluoroscopy frequency, fracture healing time, and complications were recorded and compared, and hip function was evaluated by Harris score at last follow-up. Postoperative anteroposterior and lateral hip X-ray films were taken to assess screw distribution accuracy, including deviation from the femoral neck axis, inter-screw parallelism, and distance from screws to the femoral neck cortex. Results No significant difference was observed in operation time between the two groups (P>0.05). However, the navigation group demonstrated superior outcomes in intraoperative blood loss, fluoroscopy frequency, deviation from the femoral neck axis, inter-screw parallelism, and distance from screws to the femoral neck cortex (P<0.05). No incision infections or deep vein thrombosis occurred. All patients were followed up 12-18 months (mean, 16 months). In the freehand group, 1 case suffered from cannulated screw dislodgement and nonunion secondary to osteonecrosis of femoral head at 1 year after operation, 1 case suffered from screw penetration secondary to osteonecrosis of femoral head at 5 months after operation; and 1 case suffered from nonunion secondary to osteonecrosis of femoral head at 6 months after operation in the navigation group. All the 3 patients underwent internal fixators removal and total hip arthroplasty. There was no significant difference in the incidence of complications between the two groups (P>0.05). The fracture healing time and hip Harris score at last follow-up in the navigation group were significantly better than those in the freehand group (P<0.05). ConclusionCompared to freehand percutaneous screw fixation, Holosight robotic navigation-assisted cannulated screw fixation for femoral neck fractures achieves higher precision, reduced intraoperative radiation exposure, smaller incisions, and superior postoperative hip function recovery.
