Experience in surgical treatment of type Ⅱ odontoid fractures: A report of two cases and review of the literature / 中华创伤杂志(英文版)

Two cases of type Ⅱ odontoid fractures were reported to share our experience in surgery treatment of such cases. A 33-year-old woman with comminuted type Ⅱ odontoid fracture and a 42-year-old man with fracture end hardened type Ⅱ odontoid fracture received surgical treatment in our hospital. Though imaging examination suggested that these two patients were suitable for anterior screw fixation, we encountered difficulties during the operation. The two patients eventually underwent posterior C

Treatment of odontoid fracture combined with lower cervical spinal cord injuries without fracture or dislocation / 中国修复重建外科杂志

Objective: To discuss the clinical characteristics, mechanism, and treatment of odontoid fracture combined with lower cervical spinal cord injuries without fracture or dislocation.

Clinical Results of Odontoid Fractures according to a Modified, Treatment-Oriented Classification

OBJECTIVE: Odontoid fracture is common in cervical injury, representing about 20% of total cervical fractures. Classic odontoid fracture classification focused on anatomy of fracture site has no treatment recommendation and a modified treatment-oriented classification of odontoid fracture was suggested in 2005. We reviewed our odontoid fracture patients to assess the feasibility and efficacy of Grauer's classification. METHODS: Between October 2000 and September 2015, we collected data from patients who came to our institute for odontoid fracture. Demographic data of patients was reviewed, and neck visual analog scale (VAS) score and fusion rate were assessed by reviewing electronic medical records retrospectively. RESULTS: Sixty-nine patients out of a total of eighty two odontoid fracture patients were reviewed according to Grauer's classification. Neck VAS of all subtypes in odontoid fracture classification were decreased at last follow-up (p=0.001). Overall fusion rate was 88.4% at last follow-up. Concordance rate between Grauer's recommendation and our treatment was 69.9%, especially in type II with the concordance higher than 80%. Complication was minimal representing 7.2%, only in types I and III. CONCLUSION: In this study, there were statistically significant improvement in all subtypes in terms of neck VAS at the last follow up, especially in types II and III. Grauer's classification appears to be meaningful to decide treatment plan for odontoid fractures, especially type II odontoid fracture.

Biomechanical Comparison of Inter-fragmentary Compression Pressures: Lag Screw versus Herbert Screw for Anterior Odontoid Screw Fixation

OBJECTIVE: The purpose of the present study was to compare inter-fragmentary compression pressures after fixation of a simulated type II odontoid fracture with the headless compression Herbert screw and a half threaded cannulated lag screw. METHODS: We compared inter-fragmentary compression pressures between 40- and 45-mm long 4.5-mm Herbert screws (n=8 and n=9, respectively) and 40- and 45-mm long 4.0-mm cannulated lag screws (n=7 and n=10, respectively) after insertion into rigid polyurethane foam test blocks (Sawbones, Vashon, WA, USA). A washer load cell was placed between the two segments of test blocks to measure the compression force. Because the total length of each foam block was 42 mm, the 40-mm screws were embedded in the cancellous foam, while the 45-mm screws penetrated the denser cortical foam at the bottom. This enabled us to compare inter-fragmentary compression pressures as they are affected by the penetration of the apical dens tip by the screws. RESULTS: The mean compression pressures of the 40- and 45-mm long cannulated lag screws were 50.48±1.20 N and 53.88±1.02 N, respectively, which was not statistically significant (p=0.0551). The mean compression pressures of the 40-mm long Herbert screw was 52.82±2.17 N, and was not statistically significant compared with the 40-mm long cannulated lag screw (p=0.3679). However, 45-mm Herbert screw had significantly higher mean compression pressure (60.68±2.03 N) than both the 45-mm cannulated lag screw and the 40-mm Herbert screw (p=0.0049 and p=0.0246, respectively). CONCLUSION: Our results showed that inter-fragmentary compression pressures of the Herbert screw were significantly increased when the screw tip penetrated the opposite dens cortical foam. This can support the generally recommended surgical technique that, in order to facilitate maximal reduction of the fracture gap using anterior odontoid screws, it is essential to penetrate the apical dens tip with the screw.

Biomechanical Assessment of Stabilization of Simulated Type II Odontoid Fracture with Case Study

STUDY DESIGN: Researchers created a proper type II dens fracture (DF) and quantified a novel current posterior fixation technique with spacers at C1–C2. A clinical case study supplements this biomechanical analysis. PURPOSE: Researchers explored their hypothesis that spacers combined with posterior instrumentation (PI) reduce range of motion significantly, possibly leading to better fusion outcomes. OVERVIEW OF LITERATURE: Literature shows that the atlantoaxial joint is unique in allowing segmental rotary motion, enabling head turning. With no intervertebral discs at these joints, multiple ligaments bind the axis to the skull base and to the atlas; an intact odontoid (dens) enhances stability. The most common traumatic injury at these strong ligaments is a type II odontoid fracture. METHODS: Each of seven specimens (C0–C3) was tested on a custom-built six-degrees-of-freedom spine simulator with constructs of intact state, type II DF, C1–C2 PI, PI with joint capsulotomy (PIJC), PI with spacers (PIS) at C1–C2, and spacers alone (SA). A bending moment of 2.0 Nm (1.5°/sec) was applied in flexion-extension (FE), lateral bending (LB), and axial rotation (AR). One-way analysis of variance with repeated measures was performed. RESULTS: DF increased motion to 320%, 429%, and 120% versus intact (FE, LB, and AR, respectively). PI significantly reduced motion to 41%, 21%, and 8%. PIJC showed negligible changes from PI. PIS reduced motion to 16%, 14%, and 3%. SA decreased motion to 64%, 24%, and 54%. Reduced motion facilitated solid fusion in an 89-year-old female patient within 1 year. CONCLUSIONS: Type II odontoid fractures can lead to acute or chronic instability. Current fixation techniques use C1–C2 PI or an anterior dens screw. Addition of spacers alongside PI led to increased biomechanical rigidity over intact motion and may offer an alternative to established surgical fixation techniques.

Clinical analysis of the self made needle guide for the treatment of odontoid fracture / 中国骨伤

<p><b>OBJECTIVE</b>To analyze the curative effects and feasibility of the self regulating simple localizer through anterior approach for the treatment of odontoid fracture in adults.</p><p><b>METHODS</b>From June 2010 and December 2012, 6 patients with odontoid fracture underwent an anterior operation using a single hollow screw located by the self regulating simple localizer. There were 4 males and 2 females, aged from 28 to 55 years old with an average of 39.1 years. The injuries were caused by traffic accidents in 4 cases and falling injury from high in 2 cases. According to the classification of Anderson, 4 cases were type II and 2 cases were simple type III. All the patients underwent operations in 5 to7 days after injury with the mean of 5.9 days. None of the patients had a spinal cord injury. The safety and feasibility of the self made localizer were observed in follow up for fracture healing and clinical effects.</p><p><b>RESULTS</b>All the operations were successful with an average time of 50 min (ranged from 45 to 55 min) and the mean bleeding volume was 25 ml(ranged from 20 to 30 ml). No injuries of esophagus, trachea or nerve were found. All the patients were followed up from 8 to 16 months and all fractures were obtained bone healing. The flexion extension radiograph showed a well stability of atlantoaxial joint in last followed up.</p><p><b>CONCLUSIONS</b>The self regulating simple localizer is a minimally invasive, short time and safe method in treating odontoid fractures through anterior operation with hollow screw. It may be a reliable choice while without a professional localizer.</p>

Surgical treatment with cable dragged reduction and cantilever beam internal fixation by posterior approach for odontoid fracture associated with atlantoaxial dislocation / 中国骨伤

<p><b>OBJECTIVE</b>To explore the clinical effects of surgical treatment with cable dragged reduction and cantilever beam internal fixation by posterior approach for odontoid fracture associated with atlantoaxial dislocation.</p><p><b>METHODS</b>The clinical data of 12 patients with odontoid fracture associated with atlantoaxial dislocation from January 2008 to December 2013 were retrospectively analyzed. There were 8 males and 4 females, ranging in age from 21 to 53 years with an average of 37.2 years. Eleven cases were fresh fracture and 1 case was old fracture, all patients complicated with atlantoaxial anterior dislocation. According to Anderson-D' Alonzo typing method modified by Grauer, 3 cases were type IIA, 5 cases were type IIB, 3 cases were type IIC, and 1 case was type IIIA. All patients underwent surgical treatment with cable dragged reduction and cantilever beam internal fixation by posterior approach. JOA score and ADI method were respectively used to evaluate the nerve function and reductive condition of atlantoaxial dislocation.</p><p><b>RESULTS</b>All patients were followed up from 6 months to 2 years with an average of 1 year and 3 months. At 1 week, 6 months after operation, and final follow up, JOA scores were 13.2±1.3, 13.5±1.4, 14.3±1.5, respectively, and these data were obviously better than that of preoperative 8.3±1.4(<0.05). Postoperative X rays and CT showed satisfactory reduction of atlantoaxial dislocation. At 1 week, 6 months after operation, and final follow up, ADI were (2.2±0.4), (2.4±0.6), (2.3±0.5) mm, respectively, and these data were obviously better than that of preoperative.(5.8±1.2) mm(<0.05). All screws and cables had good location without looseness and breakage, and bone graft got fusion.</p><p><b>CONCLUSIONS</b>Surgical treatment with cable dragged reduction and cantilever beam internal fixation by posterior approach for odontoid fracture associated with atlantoaxial dislocation is a good method, with advantage of firm fixation and high safety. It could obtain good clinical effects.</p>

Odontoid Synchondrosis Fracture Treated by C1-2 Polyaxial Screw-Rod Fixation

The synchondrosis between the dens and the body of axis normally fuses between 5 and 7 years of age. Until this age, synchondrosis fractures can occur in children. Most synchondrosis fractures are conventionally treated by external immobilization alone. We report a 10-year-old child with odontoid synchondrosis fracture who was treated by C1 lateral mass and C2 pars screw rod fixation with a successful outcome and discuss the possible reasons for occurrence of odontoid synchondrosis fracture in this older child as well as the indications for surgery in this condition.

Design of digitized anterior approach screw fixation program：Clinical application in the treatment of type Ⅱ odontoid fractures / 中国组织工程研究

10.3969/j.issn.2095-4344.2013.26.024

Anterior Screw Fixation of Anteriorly Displaced Type III Odontoid Fracture Corrected by Transoral Digital Manipulation

Type III odontoid fractures have been treated by several methods. In case of anteriorly displaced type III odontoid fracture which is not corrected by closed reduction, anterior screw fixation cannot be used. We report the first case of anterior screw fixation of anteriorly displaced type III odontoid fracture corrected by transoral digital manipulation.

Fractura de Jefferson asociada a fractura de apófisis odontoides, tratamiento conservador: reporte de un caso / Jefferson fracture associated with fracture of odontoid process, conservative treatment: a case report

Las Fracturas por estallido del atlas (fracturas de Jefferson: Nombrada así por Sir Geoffrey Jefferson1) se producen cuando una fuerza axial se transmite a través de la unión occipito-cervical, causando que el atlas sea comprimido entre la superficie articular de la angulación del Axis y los cóndilos occipitales. Las fuerzas de impacto causan una propagación hacia el exterior de las masas laterales de C1. El resultado es una fractura del atlas en cuatro partes, dos en el arco posterior y dos en el arco anterior2. Y la fractura de apófisis odontoides principalmente por flexion que es el mecanismo más común que produce el daño con el consecuente desplazamiento anterior de la apófisis de la primera vértebra cervical (C1) sobre la segunda (C2). Debido a extensión sólo ocasionalmente se producen FAPO (fractura de apófisis Odontoides), usualmente asociadas con desplazamiento posterior5,9. La frecuencia de accidentes fatales como consecuencia directa de esta lesión es desconocida pero se estima entre un 25 a un 40 por ciento6,7. El manejo de esta es aún controvertido. La mayoría son relativamente estables y no se asocia con deficiencias neurológicas y pueden ser tratadas mediante inmovilización externa con resultados satisfactorios9. Las fracturas inestables de Jefferson reflejan una lesión más grave del atlas que se producen cuando el ligamento transverso también se rompe, secundario a la extensión de la propagación del arco de Cl. Estas fracturas son más difíciles de tratar debido a la inestabilidad atlantoaxial. Muchos cirujanos recomiendan la estabilización quirúrgica de estas fracturas de Jefferson inestables.

The atlas burst fractures (Jefferson fractures: Named after Sir Geoffrey Jefferson1) occur when an axial force is transmitted through the occipito-cervical junction, causing the atlas is compressed between the articular surface of the Axis and angle of the occipital condyles. Impact forces cause an outward propagation of the lateral masses of C1. The result is a fracture of the atlas into four parts, two in the posterior arch and two in the anterior arch2. And the odontoid fracture mainly by flexion is the most common mechanism that causes the damage with the resulting anterior displacement of the apophysis of the first cervical vertebra (C1) on the second (C2). Because there are only occasional extension FAPO (odontoid fracture), usually associated with posterior displacement5,9. The frequency of fatal accidents as a direct result of this injury is unknown but is estimated between 25 to 40 percent6,7. Managing this is still controversial Most are relatively stable and is not associated with neurological deficits and can be treated by external immobilization with satisfactory results9. Unstable fractures of Jefferson reflect a more serious injury of the atlas that occur when the transverse ligament also ruptures secondary to the extent of spread of the arch of Cl These fractures are more difficult to treat due to atlanto-axial instability. Many surgeons recommend surgical stabilization of these unstable Jefferson fractures.

Atlantoaxial pedicle screw fixation for old odontoid fracture combined with atlantoaxial instability / 中华创伤杂志

Objective To explore the clinical effect of the trans-atlantoaxial pedicle screw-rod internal fixation and fusion in treatment of old odontoid fracture combined with atlantoaxial instability.Methods The study involved 48 patients with old odontoid fractures combined with atlantoaxial instability treated with trans-atlantoaxial pedicle screw-rod internal fixation and fusion from January 2005 to January 2010.There were 30 males and 18 females,at average age of 45.1 years old(19-56 years).All the patients underwent the skull traction preoperatively.Results A total of 192 pedicle screws(96 screws for the atlas and another 96 for the axis)were implanted in all the 48 patients who obtained satisfactory atlantoaxial reduction,with no spinal cord injuries.The operation lasted for average 155 min,with blood loss for average 370 ml.There were three patients with vertebral artery injury and three with inferior posterior arch fracture of the atlas during operation.All the patients were followed up for average of 46.6 months(range,9-64 months),which showed bone fusion at 6 months after operation,with no loosening,displacement,instability or breakage of the screws.The JOA score was improved from preoperative 7.1 ±2.8 to postoperative 13.3 ± 2.1(P ＜ 0.05).Conclusion Atlantoaxial pedicle screw fixation is a reliable and effective method for the treatment of the atlantoaxial instability.

Clinical Outcomes of Halo-Vest Immobilization and Surgical Fusion of Odontoid Fractures

OBJECTIVE: In the present study, authors retrospectively reviewed the clinical outcomes of halo-vest immobilization (HVI) versus surgical fixation in patients with odontoid fracture after either non-surgical treatment (HVI) or with surgical fixation. METHODS: From April 1997 to December 2008, we treated a total of 60 patients with upper cervical spine injuries. This study included 31 (51.7%) patients (22 men, 9 women; mean age, 39.3 years) with types II and III odontoid process fractures. The average follow-up was 25.1 months. We reviewed digital radiographs and analyzed images according to type of injury and treatment outcomes, following conservative treatment with HVI and surgical management with screw fixation. RESULTS: There were a total of 31 cases of types II and III odontoid process fractures (21 odontoid type II fractures, 10 type III fractures). Fifteen patients underwent HVI (10 type II fractures, 5 type III fractures). Nine (60%) out of 15 patients who underwent HVI experienced successful healing of odontoid fractures. The mean period for bone healing was 20.2 weeks. Sixteen patients underwent surgery including anterior screw fixation (6 cases), posterior C1-2 screw fixation (8), and transarticular screw fixation (2) for healing the odontoid fractures (11 type II fractures, 5 type III fractures). Fifteen (93.8%) out of 16 patients who underwent surgery achieved healing of cervical fractures. The average bone healing time was 17.6 weeks. CONCLUSION: The overall healing rate was 60% after HVI and 93.8% with surgical management. Patients treated with surgery showed a higher fusion rate and shorter bony healing time than patients who received HVI. However, prospective studies are needed in the future to define better optimal treatment and cost-effective perspective for the treatment of odontoid fractures.

Traumatic Atlantoaxial Rotatory Fixation with Accompanying Odontoid and C2 Articular Facet Fracture

Traumatic atlantoaxial rotatory fixation (AARF) with accompanying odontoid and C2 articular facet fracture is a very rare injury, and only one such case has been reported in the medical literature. We present here a case of a traumatic AARF associated with an odontoid and comminuted C2 articular facet fracture, and this was treated with skull traction and halo-vest immobilization for 3 months. After removal of the halo-vest immobilization, his neck pain was improved and his neck motion was preserved without any neurologic deficits although mild torticolis was still observed in closer inspection.

Clinical Analysis of Axis Fracture

This retrospective analysis describes the clinical characteristics, treatment, and long-term outcome of 30 patients with axis fracture admitted to our institution between January 1991 and December 1995. The incidence of axis fracture was 27.2% in the 110 cervical spine fractures. Among these, odontoid process fracture was the most common type, 19 cases(63%) followed by 8 hangmans fractures(27%), 3 miscellaneous fractures(10%). Hangman's fractures, odontoid type III fractures and miscellaneous fractures were treated with external immobilization devices. Remaining 11 odontoid type II fractures, and six patients with dens dislocation of 6 mm or greater were initially treated by early surgical stabilization. Individuals with dens dislocated less than 6 mm were treated by external immobilization only. Among the nonoperative group of acute axis fractures, there was no fusion failure. In the early operated group, all patients were stable clinically or radiologically. But three patients with posterior wiring and bone graft complained of their neck motion limitation.

Surgical Treatment of Odontoid Type II Fracture with Anterior Screw Fixation: Analysis of 15 Cases

Fracture of the odontoid process is subdivided into type I, II and III. The treatment of type II is problematic, in that both conservative treatment and surgery are usually unsatisfactory; in the other type, conservative management alone gives good results. Recently, however, the operative procedure has changed, in accordance with advances in surgical equipment and technique. The anterior or posterior approach may be used, and the anterior screw fixation is increasingly the operaive procedure of choice; indications, operative technique, complications and long-term prognosis have not, however, been reported. The procedure was initially applied to patients who had suffered posterior displacement, and in whom nonunion was likely, but because of improved equipment and technique, was seem to be succesful and safe and so was used in the initial management of all odontoid type II fracture. A anterior screw fixation effectively attaches displaced bony fragment to the odontoid process and immobilizes one that is fractured. The BOP(Biocompatible Osteoconductive Polymer) pin is more physiologic than metal screw, and does not compromise the area to be fused, eventhough it has no lag effect. The major advantages of anterior fixation are immediate stability and restoration, and the preservation of normal biomechanics of the spine. It can be used as the procedure of choice in most patients with odontoid type II fracture, while anterior fixation with a BOP pin may be suitable for some selected patients.

Clinical Evaluation of Direct Anterior Screw Fixation of Odontoid Fractures

dontoid fractures have been treated either conservatively or by surgical fixation, and whether one method is better than the other is still controversial. Because it more effectively overcomes the problems of fracture instability and nonuinon, operative stabilization is now favored over external immobilization for the treatment of Type IIodontoid fractures. Most surgical stabilizations of such fractures use posterior cervical wiring techniques with C1-C2 arthrodesis; these, however, obliterate the rotation and flexion/extension of the atlantoaxial complex,and in Type II-P fractures, provide little resistance to further posterior subluxation. As no arthrodesis is performed, direct anterior screw fixation of odontoid fractures theoretically stabilizes the atlantoaxial complex and preserves its motion. Between January 1993 and December 1996, we performed eleven anterior screw fixations in patients who had suffered odontoid fractures(Type II, III); these were postoperatively followed up for an average of 27 months. Excepet for two cases of permissible malunion, thought to be due to fixation on a partially reduced state, all eleven cases showed firm union at the fracture site, with no significant disabilities and complications. The results indicate that in odontoid fracture reduction and eventual fracture union, the outcome of anterior screw fixation is excellent; there is, in addition, no decrease in cervical motion, a disadvantage inherent in currently accepted methods of treatment.

Unstable C1, 2 Cervical Spine Injuries Treated with Halo vest / 대한정형외과학회잡지

In a consecutive series of 15 patients with unstable C1,2 cervical spine injuries treated with halo vest, 1992-1996, a total 7 patients (comprising 46%) among the patients with C1,2 cervical spine injuries, had odontoid fractures, no patient had neurologic injury. In all cases, initial treatment was Halter or skull traction for 1-2weeks. In the vitally stable state, they were stabilized with halo vest for 12-16 weeks. In 2 cases of C1,2 instability, initial treatment was internal fixation and halo vest for the same time. 2 cases of the patients, who were treated with halo vest, had additional posterior wiring and fusion due to instability checked after removal of halo vest. There was no other serious complications during the treatment. One case (25%) of 4 Anderson-d' Alonzo type II fractures was failed to unite. The halo vest was well tolerated in all patients and assured a high percentage of healing. Flexion-extension motion was measured with dynamic lateral cervical tomography. The age range was 17-67 (mean 41.3) years and male/female ratio was 3/2. Complications during the treatment were pin loosing (1 case) and halo vest frame breakage due to falling down. Pain on motion and stiffness of neck were the most frequently remained symptoms. But the symptoms were mild and did not usually have any major impact on return to work or leisure activities.

Delayed Nonunion of a Type II Odontoid Fracture, after Apparent Bony Fusion: Case Report

We managed a 27-year-old woman, who suffered from a type II odontoid fracture, with a halo-vest. After 12 weeks, we confirmed bony fusion on cervical spine CT and managed her with a neck collar. During the OPD follow up, we checked the cervical spine film every 1 month. After two and half months, displaced odontoid process was noted on routine cervical film, and a bony gap was found at the previous fracture wite on cervical spine CT. There is only one report in the literlature describing a nonunion after radiographically confirmed healing of a type II odontoid fracture. We report this case in order to emphasize the importance of scheduled follow up examination and evaluate precipitating factors of delayed nonunion of odontoid fracture.

Comparison of Clinical Findings and Results of Treatment According to Classification of C-2 Fractures

There are some debates on the best method of treatment of C-2 fractures. Clinical findings and results of treatment were evaluated in forty-three patients with C-2 fractures. These fractures were classified into five types according to the classification by Benzel4);1) odontoid fractures(14), 2) horizontal C-2 body fractures(13), 3) sagittally oriented vertical C-2 body fractures (2), 4) coronally oriented vertical C-2 body fractures(8), 5) traumatic spondylolisthesis of the axis(6). Primary fusion appears to be justified in odontoid process fractures due to a high rate of non-union. In horizontal C-2 body fractures, unilateral facet dislocation was visible in six patients which was the cause of malalignment in closed reduction. In sagittally oriented vertical C-2 body fractures, combined facet fractures were always visible because the mechanism of injury was axial compression. The choice of management schemes may depend on the mechanism of injury and fracture type defined by Benzel.