Objective:To investigate the clinical significance of a new classification system for atlas fractures based on pre- and post-treatment CT features, with a focus on diagnosis and treatment.Methods:A retrospective analysis was conducted on 75 cases of cervical vertebra fractures treated at the Sixth Hospital of Ningbo City between January 2015 and December 2020. The study included 44 males and 31 females, with an average age of 53.3±13.0 years (range: 27-81 years). The fractures were classified according to the Landells classification, resulting in 12 cases of type I, 13 cases of type II, 33 cases of type III, 9 cases that were difficult to classify due to fracture lines located at anatomical junctions, and 8 cases that could not be classified using the Landells classification due to diverse injury mechanisms. To establish a new preliminary classification for cervical vertebra fractures, the researchers considered whether the fracture line in the CT images involved the facet joint surface of the atlas, the impact on bilateral half-rings, and the displacement distance of the fracture ends. Five spinal surgeons were randomly selected to classify the CT images of the 75 patients using the new classification method. After one month, the imaging data of the 75 cases of cervical vertebra fractures were randomized and reclassified to assess the reliability and repeatability of the classification.Results:The new cervical vertebra fracture classification method comprised three types based on whether the fracture line involved the facet joint surface of the atlas: type A (no involvement of the facet joint surface of the atlas), type B (involvement of one side of the facet joint surface with intact contralateral half-ring), and type C (involvement of one side of the facet joint surface with fractured contralateral half-ring). Additionally, based on the maximum displacement distance between the fracture ends (>4 mm), six subtypes were identified: subtype 1 (≤4 mm displacement) and subtype 2 (>4 mm displacement). Consequently, the subtypes were classified as A1, A2, B1, B2, C1, and C2. According to the new classification method, the 75 patients included 17 cases of A1, 12 cases of A2, 7 cases of B1, 13 cases of B2, 12 cases of C1, and 14 cases of C2. The classification demonstrated excellent consistency, as assessed by the five doctors, with Kappa values of 0.85 and 0.91 for reliability and repeatability, respectively. At the final follow-up, all conservatively treated patients achieved bone healing, while four surgically treated patients experienced non-union of the fracture ends but exhibited good fusion between the atlas and axis. The remaining surgically treated patients achieved bony union without complications such as loosening or fracture of internal fixation.Conclusion:The new cervical vertebra fracture classification method, based on CT imaging features, comprehensively covers common clinical cases of cervical vertebra fractures and demonstrates excellent consistency. It provides valuable clinical guidance for the diagnosis and treatment of cervical vertebra fractures.

Objective: To investigate the clinical effect of the reserve-flow anterolateral thigh perforator flap based on aesthetics concept to repair soft tissue defect around the knee joint. Methods: From June 2016 to April 2017, 10 patients with skin and soft tissue defects around the knee joint were admitted to Mingzhou Hospital of Zhejiang University. The area of the soft tissue defects around the ankle were ranged from 5.0 cm × 3.0 cm to 11.0 cm × 7.5 cm after debridement. The anterolateral thigh perforator flaps were designed on the ipsilateral lateral thigh, according to the results of preoperative perforator detection. The reserve-flow anterolateral thigh perforator flaps based on aesthetic concept were used to repair the wound through the subcutaneous tunnel. The flaps were 5.5 cm × 3.5 cm to 12.0 cm × 8.0 cm in size. The donor sites were directly closed. Results: The flaps of 9 patients completely survived, however, epidermal necrosis occurred to 1 patient, at the distal end of the flap, about 1 cm × 1 cm in size. It completely healed after dressing change for 1 week. The follow up time was from 8 to 15 months (mean 12 months). The flaps were satisfactory in appearance, good in the elasticity, nearly normal in color, and had protective sensation. The two-point discrimination perception ranged from 9 to 13 mm(mean 10 mm). The donor and recipient sites only remained linear scars, with no depression deformity. The lower limb functions were normal. Conclusions The reverse-flow anterolateral thigh flap based on aesthetic concept, is an alternative method to repair the soft tissue defect around the knee joint, and protect the donor site to the maximum extent.

In recent years,the surgical treatment of thoracolumbar fractures has made great progress.The thoracolumbar injury classification and severity score (TLICS) of thoracolumbar injuries and the new AO classification,as the most widely used classification score in clinical application,have a clear guiding significance for clinical treatment and scientific research.With the extensive application of CT and MRI,the divergence in the diagnosis of posterior ligament complex (PLC) injury in scoring systems has been narrowed.With the wide application of pedicle screw and the deeper understanding of the anatomical and mechanical characteristics of spine,posterior pedicle screw fixation has been gradually adopted as the major method,while anterior or posterior pedicle screw fixation is only used in special cases.Because of the in-depth study of pedicle screw mechanics,more and more attention has been paid to the fixation of injured vertebrae.Moreover,with the intensive study of sagittal balance of the spine,the reconstruction of injured vertebrae has been proposed as a new concept and further investigated.The author discusses thoracolumbar fracture scoring system,surgical approach,surgical fixation segment,bone graft reconstruction and minimally invasive treatment so as to provide some reference.

Objective To evaluate the clinical efficacy of universal self-locking anatomical plate for acetabulum and pelvis (USAPAP) in the treatment of posterior acetabular fractures.Methods Data of 55 patients with posterior acetabular fractures who were treated with the USAPAP from January 2014 to January 2016 were retrospectively analyzed.There were 39 males and 16 females with an average age of 38.5 years old (range,17-82 years).There were 35 fractures on the left side while the other 20 fractures were on the right side,including 52 fresh cases and 3 old cases.According to Letournel-Judet classification,there were 32 cases of posterior wall,9 cases of transverse and posterior wall,5 cases of anterior column and posterior wall,2 cases of posterior column,2 cases of transverse,2 cases of two columns,1 case of anterior column and posterior hemitransverse,2 cases of Pipkin type Ⅳ.All patients were managed operatively by the USAPAP,which allows simultaneous fixation for two columns and quadrilateral surface fractures through a single Kocher-Langenback approach.The quality of reduction was assessed by Matta's score system.The mean follow-up period was 18.5 months (range,12-24 months).Average operation time was 95 min,and average blood loss was 350 ml.Average operation time of plate and screws fixation was 19 min,and average fluoroscopy times in the surgery was 2 times.The mean time of bony union was 4.3 months.According to the criteria described by Matta,the excellent and good rate of radiological score was 92.7％ (51/55),including 39 cases excellent,12 cases good and 4 cases poor.The excellent and good rate of Merle d'Aubigne-Postel score was 87.3％ (48/55),including 35 cases of excellent,13 cases of good,5 cases of fair,and 2 cases of poor.Heterotopic ossification occurred in 1 patient (Brooker type Ⅱ) at three months postoperatively.One case with Pipkin type Ⅳ fracture underwent total hip arthroplasty due to femoral head necrosis at seven months postoperatively.Complications including wound infection,sciatic nerve injury,screw invade joint,redisplacement of the fracture,avascular necrosis of bone fragment,hardware failure,nonunion or malunion was not found in any case at the latest follow-up.Conclusion The USAPAP through the single posterior Kocher-Langenback approach provides strong and stable fixation for complex acetabular fractures associated with posterior region including posterior wall,both columns and quadrilateral surface.Satisfactory clinical results can be achieved by the use of this method.

Objective To compare the clinical efficacy and fusion rate of unilateral and bilateral C1 and C2 pedicle screw fixation of unstable Jefferson fractures.Methods This retrospective casecontrol study enrolled 22 patients with unstable Jefferson fractures admitted between April 2012 and May 2015.There were 18 males and four females,with the mean age of 52.9 years (range,35-67 years).Mean preoperative visual analogue scale (VAS) was 6.09 points (range,4-8 points).According to the American spinal injury association (ASIA) classification,two patients were rated grade D and one patient grade C.Mean Japanese orthopedic association (JOA) score was 12.3 points.Bilateral C1 and C2 pedicle screw fixation was performed for 15 patients (bilateral group).Advantage side unilateral C1 and C2 pedicle screw fixation was performed for seven patients with extremely unstable fracture or narrow pedicle (unilateral group).Operation time,blood loss and surgical complications were recorded.VAS was used to evaluate the improvement of neck pain after operation.ASIA classification and JOA score were used to assess nerve function recovery.Atlanto-dental interval (ADI),srew position and bone fusion were evaluated after operation.Results All patients successfully completed the operation.Operation time was (119.5 ±21.2)min,and blood loss was (280.1 ±83.1)ml.A total of 74 screws were placed and CT scan showed satisfactory position of the screws.No complications were noted either during the operation or after surgery.All patients were followed up for mean 20.7 months (range,13-33 months).VAS was improved in both groups after operation (P ＜ 0.01),and there was no significant difference between the two groups (P ＞ 0.05).Two patients with ASIA grade D in bilateral group were improved to ASIA grade E after operation.One patient with ASIA grade C in unilateral group was improved to ASIA grade D after operation.JOA score increased to mean 15.7 points at last follow-up.ADI were decreased in both groups after operation(P ＜0.05),but there was no significant difference between the two groups (P ＞ 0.05).All patients had bony fusion 6 months after operation,with similar fusion rate between the two groups (P ＞ 0.05).Conclusion Advantage side unilateral screw fixation can be used for the patients with bilateral C1 and C2 pedicle screw fixation failure,for the technique can improve cervical pain and provide relatively high stability and fusion rate.

Objective: To explore the effect of hydrogen-rich saline on the CD4⁺ CD25⁺ Foxp3⁺ Treg cells in a guinea pig model of allergic rhinitis (AR) and investigate the underling anti-inflammatory mechanism. Methods: Using random number table, eighteen guinea pigs were divided into three groups (control group/AR group/HRS group, n=6 of each group). AR guinea pig model was built with ovalbumin and aluminum. The guinea pigs were injected with hydrogen-rich saline (HRS group) for ten days after sensitation. And control group was injected with equal normal saline at the same time. Number of sneezes, degree of runny nose and nasal rubbing movements were scored. Peripheral blood eosinophil count was recorded. The content of interleukin 10(IL-10) and transforming growth factor β (TGF-β) in the serum were detected by enzyme-linked immunosorbent assay (ELISA). Immunohistochemical method was taken to detect IL-10 and TGF-β in nasal mucosa. The proportion of CD4⁺ CD25⁺ Foxp3⁺ T cells in the CD4⁺ T cells of spleen and peripheral blood were determined with flow cytometry. SPSS 17.0 software was used to analyze the data. Results: There was significant difference in symptom scores among them. The scores of AR group preceded control group, and HRS could decrease the scores of AR ((6.29±1.79) vs (1.01±0.71), (4.50±0.84) vs (6.29±1.79), F=24.725, all P<0.05). The highest number of eosinophils in the peripheral blood belonged to control group, and the number of eosinophils were dramatically reduced after HRS administration ((0.41±0.05)×10⁹/L vs (0.25±0.03 )×10⁹/L, (0.32±0.03)×10⁹/L vs (0.41±0.05)×10⁹/L, F=70.05, all P<0.05). The content of IL-10 and TGF-β in control group is peak ((86.88±17.17) pg/ml, (598.28±72.70) pg/ml, respectively), and compared with AR group, HRS also increased the expression of IL-10 and TGF-β of peripheral blood ((72.54±11.75) pg/ml vs (53.49±10.07) pg/ml, (530.23±57.15) pg/ml vs (482.69±65.96) pg/ml, F value was 28.357, 14.128, respectively, all P<0.05). The proportion of CD4⁺ CD25⁺ Foxp3⁺ Treg cells in controls exceeded HRS group and AR group (1.81%±0.10%, 1.29%±0.74%, respectively), and HRS treatment increased the ratio of CD4⁺ CD25⁺ Foxp3⁺ Treg cells than AR group of peripheral blood ((1.50%±0.11%) vs (1.15%±0.11%), F=168.96, P<0.05). But there was no significant diferences in splene tissue ((1.01%±0.08%) vs (0.98%±0.09%), F=97.381, P>0.05). Conclusion Both the number and the cytokine secretion of CD4⁺ CD25⁺ Foxp3⁺ Treg cells are decreased in AR group, HRS may inhibit inflammatory response and ameliorate AR via improving the number and the cytokine secretion.

Objective To investigate the clinical outcomes of pedicle screw fixation assisted with the 3D printing positioning guide template for treatment of unstable atlas fractures.Methods A retrospective case series review was made on 10 patients with unstable atlas fractures undergone direct posterior C1 pedicle screw fixation assisted with the 3D printing drill guide template from September 2012 to May 2015.There were 7 males and 3 females,with a mean age of 52.6 years (range,23-75 years).All patients complained of neck pain,stiffness and decreased range of motion without neurologic deficit.Preoperative skull traction was used routinely.After the three-dimension reconstruction of cervical vertebrae,ideal trajectory for C1 pedicle screws was designed with a complementary basal template for posterior surface of atlas corresponding anatomical structure.Then the drill guide template was materialized in a rapid prototyping machine and used during operation.Start point and direction of the ideal and actual trajectories were measured after matching the position of the pre-and post-operative patients' cervical spine.Safety of pedicle screw fixation was assessed in the transverse and sagittal planes of CT scan.Operation time and blood loss were recorded.Visual Analogue Scale (VAS) of neck pain was recorded before operation and 3 months after operation.Clinical efficacy,fracture reduction,stability and surgical complications were reviewed at the follow-up.Results A total of 20 screws were inserted safely.No significant differences existed in deviation of entry point and direction between ideal and actual trajectories (P ＞0.05).Operation time was 60-90 min (mean,75 min) and intraoperative blood loss was 110-300 ml (mean,160 ml).No spinal cord or vertebral artery injury was noted during operation.All patients were followed up for 12-36 months (mean,20.5 months).VAS was improved from preoperative 7.3 (6.3-9.5) points to 1.4 (0.3-2.5) points 3 months after operation (P ＜ 0.05).All patients had normal range of motion of the cervical spine 3 months after operation.Bony fusion was achieved 6 months after operation.At the follow-up,good cervical alignment was maintained with no instrument failure and C1.2 instability.Conclusion For treatment of unstable atlas fractures,direct posterior C1 pedicle screw fixation assisted with the 3D printing drill guide template can improve the precision of screw placement,reduce complications,and preserve the function of the occipital-atlantoaxial junction.

OBJECTIVETo evaluate the biomechanical effects of the anterior cervical transpedicular-screw system (ACTPS), compared to the anterior cervical screw plate system (ACLP), in the subaxial cervical spine after 2-level corpectomy.

METHODSA verified intact finite element subaxial cervical (C3-C7) model was established and analyzed by Mimics 10.0, Rapidform XOR3, Hypermesh 10.0, CATIA5V19, ANSYS 14.0 softwares based on the CT data (C1-T1) was collected from a 28 years old male volunteer. The axial force of 75 N and moment couple of 1N·m was loaded on the upper surface of C3, which made the model movement in flexion extension, lateral bending, rotating direction, respectively. Then, recorded the range of motion, and compared the results with the in vitro biomechanical experimental data to verify the effectiveness of the model. The ACTPS model and the ACLP model were analyzed using the finite element method. The range of motion at the operation segments (C4-C7), the range of motion at the adjacent segment (C3-C4) and stress distribution under flexion, extension, lateral bending, and axial rotation were calculated, and compared the range of motion with intact model.

RESULTSThere were 85,832 elements and 23,612 nodes in the intact model of subaxial cervical spine (C3-C7) in this experiment,and the range of motion of intact model validated with the reported cadaveric experimental data. In ACTPS group the stress was been well-distributed, but the stress concentrated on the interface between screw and the titanium plate in ACLP group. There were obvious differences of the maximum stress value between the two groups. The range of motion of fixed segments in ACTPS group was smaller than ACLP group, however adjacent segment range of motion showed no significant difference. Compared with the intact group, the range of motion in flexion extension, lateral flexion, rotation direction was decreased respectively about 25°, 20° and 8°, the range of motion at adjacent segment (C3-C4) was correspondingly compensated about 0.3°, 3° and 0.1°.

CONCLUSIONSACTPS is better than ACLP in terms of biomechanical properties. It offers rigid stability, and may be more suitable for reconstruction stability of 2-level and more than 2 levels corpectomy in the subaxial cervical spine. Meanwhile, the risk of fracture of ACTPS system is lower than that of the ACLP system.

Adult ; Biomechanical Phenomena ; Bone Screws ; Cervical Vertebrae ; surgery ; Finite Element Analysis ; Humans ; Male ; Models, Anatomic ; Range of Motion, Articular ; Rotation

Objective To investigate the optimal trajectory of posterior occipital condyle screw fixation via radiological and anatomical study.Methods Twelve adult craniocervical junction complete specimens were selected.The length,width and height of occipital condyle and the inclination angle of the longest axis were measured by CT scanning and reconstruction.Subsequently,occipital condyle screws were inserted with reference to CT measurements.After screw fixation,accuracy and safety of the placement of occipital condyle screw were verified by gross observation and CT scanning.Results Preoperative measurements of height and width of the occipital condyles indicated the placement of 4.0 mm bicortical screws was secure.Left vertebral artery horizontal sections of 2 specimens were slightly pressed without damage.CT scanning identified no damage to the inner or outer wall of the occipital condyle and the hypoglossal canal.Trajectory parameters between the right and left sides were slightly different,but no significant difference was observed (P ＞ 0.05).Average screw channel length and inclination angle were (20.8 ±2.6)mm and (37.1 ± 4.7)°respectively.Angle between screw and skull base tangent was observed as (8.5 ± 1.7) °.Distance between screw axis and hypoglossal canal was observed as (3.1 ± 1.1) mm.And the distance averaged (4.6 ± 1.4) mm between occipital condyle screw entry point and skull base and (6.1 ± 1.5) mm between entry point and inside edge of the occipital condyle.Conclusion Occipital condyle can be used as a new alternative fixed point in occipitocervical fusion.

Objective To investigate the clinical effects of the posterior atlantoaxial pedicle screw fixation combined with unilateral axial spinous process and lamina screws and allogeneic bone graft for atlantoaxial instability.Methods From March 2010 to April 2014,data of 10 patients with atlantoaxial instability who had undergone atlanto-axial vertebral pedicle fixation and interbody fusion combined with posterior atlanto-axial spines lamina nails were retrospectively analyzed.There were 6 males and 4 females with an average age of 39 (range,16-62) years old.The inclusion criteria was atlantoaxial instability together with unilateral vertebral artery segment high cross deformity (7 patients) or atlantoaxial joint break bad involving unilateral pedicle (7 patients).3 patients have spinal cord disease symptoms and physical signs,both suffered limited neck mobility and pain.The VAS scores were 1-8,with an average of 3.70±2.11.Preoperative X-ray,CT three-dimensional reconstruction and MRI were collected.X-ray and CT examination were performed 7 d and 1,3,6,12 months after operation to evaluate the internal fixation and bone grafting fusion.Results There's no occurrence of cervical spinal cord and vertebral artery injury.Screws were successfully implanted.1 case's incision occurred infiltration liquid 3 days after operation.For allograft rejection consideration,we changed the plan,and the infiltrating stopped 5 days later.Other incisions were all primary healing.VAS scores were 1.01±0.89 after operation,which was significantly reduced.X-ray showed good recovery of cervical sequence after the operation,and CT revealed 1 patient with atlas pedicle screw in the medial cortex damage.Spinal canal was without infringing,and the other screw positions were normal.6 months after operation,X-ray or CT examination both showed bony fusion.Conclusion Atlantoaxial pedicle screw fixation combined with unilateral axial spinous process and lamina screws and allograft bone graft fusion for the treatment of atlantoaxial instability can observe good clinical effects.