[Radiofrequency denervation of the spine and the sacroiliac joint : A systematic literature search according to GRADE with new German S3 guideline]. / Radiofrequenzdenervation der Wirbelsäule und des Iliosakralgelenks : Eine systematische Literaturrecherche nach GRADE mit neuer S3-Leitlinie.

BACKGROUND: This article summarizes the results of the German guideline on radiofrequency denervation of the facet joints and the sacroiliac joint. Evidence on the indications, test blocks and technical parameters are presented. OBJECTIVE: The aim is to avoid overtreatment and undertreatment, which is also of socioeconomic importance. MATERIAL AND METHOD: A systematic evaluation of the literature was carried out according to the grading of recommendations assessment, development and evaluation (GRADE) approach. A multidisciplinary guideline group has developed recommendations and statements. RESULTS: Statements and recommendations were given for 20 key questions. There was an 87.5% consensus for 1 recommendation and 100% consensus for all other recommendations and statements. The guideline was approved by all scientific medical societies involved. Specific questions included the value of the medical history, examination and imaging, the need for conservative treatment prior to an intervention, the importance of test blocks (medial branch block and lateral branch block), choice of imaging for denervation, choice of trajectory, the possibility to influence the size of the lesion, stimulation, the possibility of revision, sedation and decision support for patients with anticoagulants, metal implants and pacemakers and advice on how to avoid complications. CONCLUSION: Selected patients can benefit from well-performed radiofrequency denervation. The guideline recommendations are based on very low to moderate quality of evidence.

Radiofrequency Denervation of the Spine and the Sacroiliac Joint: A Systematic Review based on the Grades of Recommendations, Assesment, Development, and Evaluation Approach Resulting in a German National Guideline.

STUDY DESIGN: Systematic review of the literature and subsequent meta-analysis for the development of a new guideline. OBJECTIVES: This manuscript summarizes the recommendations from a new clinical guideline published by the German Spine Society. It covers the current evidence on recommendations regarding the indication, test blocks and use of radiofrequency denervation. The guidelines aim is to improve patient care and efficiency of the procedure. METHODS: A multidisciplinary working group formulated recommendations based on the Grades of Recommendations, Assessment, Development, and Evaluation (GRADE) approach and the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument. RESULTS: 20 clinical questions were defined for guideline development, with 87.5% consensus achieved by committee members for one recommendation and 100% consensus for all other topics. Specific questions that were addressed included clinical history, examination and imaging, conservative treatment before injections, diagnostic blocks, the injected medications, the cut-off value in pain-reduction for a diagnostic block as well as the number of blocks, image guidance, the cannula trajectories, the lesion size, stimulation, repeat radiofrequency denervation, sedation, cessation or continuation of anticoagulants, the influence of metal hardware, and ways to mitigate complications. CONCLUSION: Radiofrequency (RF) denervation of the spine and the SI joint may provide benefit to well-selected individuals. The recommendations of this guideline are based on very low to moderate quality of evidence as well as professional consensus. The guideline working groups recommend that research efforts in relation to all aspects of management of facet joint pain and SI joint pain should be intensified.

Paediatric spine injuries in the thoracic and lumbar spine-results of the German multicentre CHILDSPINE study.

BACKGROUND: Paediatric thoracolumbar spine injuries are rare, and meaningful epidemiological data are lacking. OBJECTIVES: The aim of this study was to provide epidemiological data for paediatric patients with thoracolumbar spinal trauma in Germany with a view to enhancing future decision-making in relation to the diagnostics and treatment of these patients. MATERIALS AND METHODS: A retrospective multicentre study includes patients up to 16 years of age who were suffering from thoracolumbar spine injuries who had been treated in six German spine centres between 01/2010 and 12/2016. The clinical database was analysed for patient-specific data, trauma mechanisms, level of injury, and any accompanying injuries. Diagnostic imaging and subsequent treatment were investigated. Patients were divided into three age groups for further evaluation: age group I (0-6 years), age group II (7-9 years) and age group III (10-16 years). RESULTS: A total of 153 children with 345 thoracolumbar spine injuries met the inclusion criteria. The mean age at the time of hospitalization due to the injury was 12.9 (± 3.1) years. Boys were likelier to be affected (1:1.3). In all age groups, falls and traffic accidents were the most common causes of thoracolumbar spine injuries. A total of 95 patients (62.1%) were treated conservatively, while 58 (37.9%) of the children underwent surgical treatment. Minimally invasive procedures were the most chosen procedures. Older children and adolescents were likelier to suffer from higher-grade injuries according to the AOSpine classification. The thoracolumbar junction (T11 to L2) was the most affected level along the thoracolumbar spine (n = 90). Neurological deficits were rarely seen in all age groups. Besides extremity injuries (n = 52, 30.2%), head injuries represented the most common accompanying injuries (n = 53, 30.8%). Regarding spinal injuries, most of the patients showed no evidence of complications during their hospital stay (96.7%). CONCLUSIONS: The thoracolumbar junction was more frequently affected in older children and adolescents. The majority of thoracolumbar spinal column injuries were treated conservatively. Nevertheless, 37.9% of hospitalized children had to be treated surgically, and there was an acceptable complication rate for the surgeries that were performed.

Geriatric Odontoid Fractures: Treatment Algorithms of the German Society for Orthopaedics and Trauma Based on Expert Consensus and a Systematic Review.

STUDY DESIGN: Systematic review/expert consensus. OBJECTIVES: Fractures of the axis represent the most frequent injury of the spine in elderly patients. Both, operative and non-operative treatment are associated with a high rate of complications and mortality. The aim of this article was to summarize the current literature on the management of odontoid fractures in geriatric patients and to weigh it based on an expert consensus process. METHODS: In a joint consensus process, members of the Spine Section of the German Orthopaedic and Trauma Society (DGOU) aimed to formulate recommendations for the diagnostic workup and treatment of odontoid fractures in geriatric patients. Based on the previously published recommendations, this article is an updated version with incorporating a systematic review of the recent literature. RESULTS: Based on the new data available, the recommendations established in the initial consensus process were adapted. CONCLUSIONS: Computed tomography represents the diagnostic standard for patients with suspected injuries of the upper cervical spine. Anderson/D'Alonzo odontoid fractures type 1, non-displaced type 2, and type 3 can be treated conservatively. Even non-unions do not necessarily result in poor clinical outcome. In Anderson/D'Alonzo type 2 fractures, surgical therapy offers the advantage of relatively safe osseous healing with no increased complication rate even in elderly patients and can thus be recommended. In very high aged patients, however, a case-by-case decision should be made. When surgical stabilization of osteoporotic odontoid fractures is indicated, posterior techniques are biomechanically advantageous and can be considered the standard.

Pediatric cervical spine injuries-results of the German multicenter CHILDSPINE study.

OBJECTIVES: The aim of this study was to provide epidemiological data of pediatric patients suffering from cervical spinal trauma in Germany, in order to integrate these data in future decision-making processes concerning diagnosis and therapy. MATERIALS AND METHODS: Retrospective multicenter study includes all patients up to 16 years suffering from cervical spine injuries who were treated in six German spine centers between 01/2010 and 12/2016. The clinical databases were screened for specific trauma mechanism, level of injury as well as accompanying injuries. Diagnostic imaging and the chosen therapy were analyzed. Patients were divided into three age groups for further evaluation: age group I (0-6 years), age group II (7-9 years), age group III (10-16 years). RESULTS: A total of 214 children with 265 cervical spine injuries were included during the mentioned period. The mean age at the time of injury was 11.9 (± 3.9) years. In age group I, 24 (11.2%) patients were included, age group II consisted of 22 patients (10.3%), and 168 patients belonged to age group III (78.5%). Girls and boys were equally affected. In all age groups, falls and traffic accidents were the most common causes of cervical spine injuries. A total of 180 patients (84.1%) were treated conservatively, while 34 (15.9%) children underwent surgery. Distorsion/whiplash injury was the most common entity (n = 165; 68.2%). Children aged 0-9 years had significantly (p < 0.001) more frequent injuries of the upper cervical spine (C0-C2) compared to older age groups. Patients of age group III were more likely to suffer from injuries in subaxial localizations. Neurological deficits were rarely seen in all age groups. Head injuries did represent the most common accompanying injuries (39.8%, n = 92). CONCLUSIONS: The upper cervical spine was more frequently affected in young children. Older children more often suffered from subaxial pathologies. The majority of cervical spinal column injuries were treated conservatively. Nevertheless, 15% of the hospitalized children had to be treated surgically.

Interobserver reliability of the Gehweiler classification and treatment strategies of isolated atlas fractures: an internet-based multicenter survey among spine surgeons.

PURPOSE: Atlas (C1) fractures are commonly rated according to the Gehweiler classification, but literature on its reliability is scarce. In addition, evaluation of fracture stability and choosing the most appropriate treatment regime for C1-injuries are challenging. This study aimed to investigate the interobserver reliability of the Gehweiler classification and to identify whether evaluation of fracture stability as well as the treatment of C1-fractures are consistent among spine surgeons. METHODS: Computed tomography images of 34 C1-fractures and case-specific information were presented to six experienced spine surgeons. C1-fractures were graded according to the Gehweiler classification, and the suggested treatment regime was recorded in a questionnaire. For data analyses, SPSS was used, and interobserver reliability was calculated using Fleiss' kappa (κ) statistics. RESULTS: We observed a moderate reliability for the Gehweiler classification (κ = 0.50), the evaluation of fracture stability (κ = 0.50), and whether a surgical or non-surgical therapy was indicated (κ = 0.53). Type 1, 2, 3a, and 5 fractures were rated stable and treated non-surgically. Type 3b fractures were rated unstable in 86.7% of cases and treated by surgery in 90% of cases. Atlas osteosynthesis was most frequently recommended (65.4%). Overall, 25.8% of type 4 fractures were rated unstable, and surgery was favoured in 25.8%. CONCLUSION: We found a moderate reliability for the Gehweiler classification and for the evaluation of fracture stability. In particular, diverging treatment strategies for type 3b fractures emphasise the necessity of further clinical and biomechanical investigations to determine the optimal treatment of unstable C1-fractures.

Late Implant Failure in Cervical Disc Arthroplasty (M6-C, Spinal Kinetics) Causing Radiculopathy and Myelopathy. / Spätes Versagen einer zervikalen Bandscheibenprothese (M6-C, Spinal Kinetics) mit Radikulomyelopathie.

Cervical disc arthroplasty (CDA) is an approved surgical treatment option in selected patients with cervical spinal disc degeneration. Even though CDA is a standard procedure since 20 years, there is a lack of information about long term performance. The published reoperation rates after CDA are low and comparable to anterior cervical fusion. The authors describe a severe failure and dysfunction with a partial core dislocation of a cervical prosthesis into the spinal canal (M6-C, Spinal Kinetics, Sunnyvale, CA, USA). Six years after implantation of a cTDR (cervical Total Disk Replacement) of the M6 type at C4/5 level, a 52 year-old women presented herself with new clinical signs of cervical myelopathy and radicular pain. Complete posterior dislocation of the central core of the implant into the spinal canal was identified as a cause. The failed device was removed completely and an ACCF (anterior cervical corpectomy and fusion) was performed. Intraoperatively, rupture of the posterior portion of the mesh tissue with posterior dislocation of the whole prosthesis core was detected. This is the second described case of a severe implant failure with core dislocation in this type of cTDR device. Even though there are thousands of successful implantations and middle term outcomes, it seems to be necessary to continue with long term radiological follow up to exclude similar failure in this type of prosthesis.

OF-Pelvis classification of osteoporotic sacral and pelvic ring fractures.

OBJECTIVES: Osteoporotic fractures of the pelvis (OFP) are an increasing issue in orthopedics. Current classification systems (CS) are mostly CT-based and complex and offer only moderate to substantial inter-rater reliability (interRR) and intra-rater reliability (intraRR). MRI is thus gaining importance as a complement. This study aimed to develop a simple and reliable CT- and MRI-based CS for OFP. METHODS: A structured iterative procedure was conducted to reach a consensus among German-speaking spinal and pelvic trauma experts over 5 years. As a result, the proposed OF-Pelvis CS was developed. To assess its reliability, 28 experienced trauma and orthopedic surgeons categorized 25 anonymized cases using X-ray, CT, and MRI scans twice via online surveys. A period of 4 weeks separated the completion of the first from the second survey, and the cases were presented in an altered order. While 13 of the raters were also involved in developing the CS (developing raters (DR)), 15 user raters (UR) were not deeply involved in the development process. To assess the interRR of the OF-Pelvis categories, Fleiss' kappa (κF) was calculated for each survey. The intraRR for both surveys was calculated for each rater using Kendall's tau (τK). The presence of a modifier was calculated with κF for interRR and Cohen's kappa (κC) for intraRR. RESULTS: The OF-Pelvis consists of five subgroups and three modifiers. Instability increases from subgroups 1 (OF1) to 5 (OF5) and by a given modifier. The three modifiers can be assigned alone or in combination. In both surveys, the interRR for subgroups was substantial: κF = 0.764 (Survey 1) and κF = 0.790 (Survey 2). The interRR of the DR and UR was nearly on par (κF Survey 1/Survey 2: DR 0.776/0.813; UR 0.748/0.766). The agreement for each of the five subgroups was also strong (κF min.-max. Survey 1/Survey 2: 0.708-0.827/0.747-0.852). The existence of at least one modifier was rated with substantial agreement (κF Survey 1/Survey 2: 0.646/0.629). The intraRR for subgroups showed almost perfect agreement (τK = 0.894, DR: τK = 0.901, UR: τK = 0.889). The modifier had an intraRR of κC = 0.684 (DR: κC = 0.723, UR: κC = 0.651), which is also considered substantial. CONCLUSION: The OF-Pelvis is a reliable tool to categorize OFP with substantial interRR and almost perfect intraRR. The similar reliabilities between experienced DRs and URs demonstrate that the training status of the user is not important. However, it may be a reliable basis for an indication of the treatment score.

[Guideline-conform treatment of injuries to the subaxial cervical spine]. / Leitliniengerechte Therapie von Verletzungen der subaxialen Halswirbelsäule.

Injuries to the subaxial cervical spine are increasing and have an increased neurological risk compared to the thoracic and lumbar spines. The current treatment recommendations according to the therapeutic recommendations of the Spine Section of the German Society for Orthopedics and Trauma Surgery (DGOU) as well as the S1 guidelines of the German Trauma Society (DGU) are presented. This second part of the article describes the correct indications and treatment planning for injuries to the cervical spine. Based on the AOSpine classification for subaxial cervical spine injuries, decisions can be made about conservative or surgical treatment as well as individual details of the treatment. The underlying principles of treatment are relief of neurological structures, restoration of stability and reconstruction/preservation of the physiological alignment.

PLIF surgery with titanium-coated PEEK or uncoated PEEK cages: a prospective randomised clinical and radiological study.

PURPOSE: This study aimed to compare clinical results and fusion rates of uncoated polyetheretherketone (PEEK) cages with titanium-coated PEEK cages in posterior lumbar interbody fusion (PLIF) surgery. METHODS: A prospective randomised study including 60 patients with one- or two-segment lumbar degenerative diseases. Patients received either titanium-coated PEEK cages (group A) or uncoated PEEK cages (group B). Fusion rates were evaluated on plain X-rays and CT scans after 6 and 12 months. Clinical follow-up (visual analogue scale, VAS; Oswestry Disability Index score, ODI; EQ-5D) was performed for 24 months. RESULTS: Fifty-five patients (92%) (36 female, 19 male) had a complete follow-up. There were no statistically significant differences in demographic, peri- or intraoperative data between groups A and B. ODI, VAS and EQ-5D improved significantly (p < 0.001) after surgery without statistically significant differences between the two groups. Overall, 65 operated segments could be evaluated for fusion (group A: 29 segments, group B: 36 segments, p = 0.6). Osseous integration of the cage surface improved significantly (p < 0.001) in both groups between 6 and 12 months after surgery. At 12-month follow-up, neither radiolucency nor signs of instability or dislocation were noted. Fusion was present in CT scans as follows: (a) bone growth through cage pores (A: 100%, B: 100%); (b) bone growth outside the cages (A: 48%, B: 61%; p = 0.3). CONCLUSIONS: PEEK and titanium-coated PEEK cages for PLIF produce equally favourable clinical and radiological results up to 24 months post-surgery. The fusion rate was not different.

[Guideline-conform diagnostics for injuries of the subaxial cervical spine]. / Leitliniengerechte Diagnostik bei Verletzungen der subaxialen Halswirbelsäule.

Injuries to the subaxial cervical spine are increasing and have a high risk for neurological injury in comparison to the thoracic and lumbar spine. The current treatment recommendations according to the recommendations of the section spine of the German Society for Orthopaedics and Trauma (DGOU) and the S1 guidelines of the German Society for Trauma Surgery are summarized in this article. High-energy as well as low-energy trauma can cause a significant injury to the cervical spine. If there is a suspicion of a cervical spine injury, a tomographic imaging modality (CT/MRI) is the procedure of choice. Injuries should be classified according to the AOSpine classification for subaxial injuries. Based on this classification, a decision on a conservative or operative treatment regimen as well as individual details of the treatment can be made.

[Diagnostics and treatment of cervical spine trauma in pediatric patients : Recommendations from the Pediatric Spinal Trauma Group]. / Diagnostik und Therapie von Verletzungen der Halswirbelsäule im Kindesalter : Empfehlungen der AG Wirbelsäulentrauma im Kindesalter.

BACKGROUND: Severe cervical spine injuries in children under the age of 17 years are rare. Recommendations or even guidelines for the diagnostics and treatment of such injuries in children are currently not available. OBJECTIVE: The aim of the study was to formulate recommendations for diagnostics and treatment of injuries of the cervical spine in pediatric patients. MATERIAL AND METHODS: First, a search of primary and secondary literature on the topic complex of diagnostics and treatment of cervical spine injuries in children was carried out. An appropriate internal literature database was defined and maintained. Second, within the framework of 9 meetings from April 2017 to December 2019 the members of the Pediatric Spinal Trauma Group of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU) systematically formulated recommendations for the diagnostics and treatment of injuries of the cervical spine in pediatric patients by a consensus process. RESULTS: Recommendation for the diagnostics and treatment for injuries of the cervical spine could be formulated for three age groups (age group I: 0-6 years; age group II: 7-9 years; age group III: 10-16 years). The diagnostic and therapeutic principles known from adult patients suffering from injuries to the cervical spine cannot be easily transferred to pediatric patients. CONCLUSION: Injuries to the pediatric spine are rare and should be treated in specialized spine centers. Pediatric patients with a stable cardiopulmonary status should undergo magnetic resonance imaging (MRI) if a spinal trauma is suspected. Classification systems and therapeutic recommendations for injuries to the cervical spine known from adult patients could also be used for adolescent patients. This is not possible for children under the age of 10 years. Only few classification systems exist for this age group. Basic principles of the treatment of spinal trauma in children is the restoration of spinal stability and correct anatomical relationships as well as the protection of all neural structures.

[Diagnostics and treatment of thoracic and lumbar spine trauma in pediatric patients : Recommendations from the Pediatric Spinal Trauma Group]. / Diagnostik und Therapie von Verletzungen der Brust- und Lendenwirbelsäule im Kindesalter : Empfehlungen der AG Wirbelsäulentrauma im Kindesalter.

BACKGROUND: Spinal injuries in pediatric patients are overall very rare. Current reference studies including large patient numbers that enable the formulation of evidence-based recommendations on diagnostics and treatment of these injuries do not exist. OBJECTIVE: The aim of the current study was to formulate recommendations on the diagnostics and treatment for injuries of the thoracic and lumbar spine in pediatric patients. MATERIAL AND METHODS: Firstly, a search for primary and secondary literature on the topic of diagnostics and treatment of spinal injuries in children was carried out. From this, a literature database was established and maintained. Secondly, within the framework of 9 meetings in the time period from April 2017 to December 2019 the members of the Pediatric Spinal Trauma Group of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU) documented recommendations on diagnostics and treatment of injuries of the thoracic and lumbar spine in pediatric patients by a consensus process. RESULTS: Recommendations on the diagnostics and treatment of injuries of the thoracic and lumbar spine could be given for 3 age groups (age group I: 0-6 years; age group II: 7-9 years; age group III: 10-16 years). Diagnostic and therapeutic principles known from adult patients suffering from injuries to the thoracic or lumbar spine cannot easily be transferred to pediatric patients. CONCLUSION: Spinal injuries in childhood are rare and should be treated in specialized spine centers. Pediatric patients with a stable cardiopulmonary status should undergo magnetic resonance imaging (MRI) if a spinal trauma is suspected. The basic principles of the treatment of spinal trauma in children is the restoration of spinal stability and correct anatomical parameters as well as the protection of all neural structures. The potential for correction and regeneration of the individual spinal sections depending on the age of the patient must be considered for deciding between operative vs. conservative treatment. Whenever operative treatment is needed, it should be performed by minimally invasive techniques as a sole instrumentation without spondylodesis. An early removal of the screw-rod-system should be performed.

[Pediatric spine trauma-Results of a German national multicenter study including 367 patients]. / Wirbelsäulenverletzungen im Kindesalter ­ Ergebnisse einer nationalen Multizenterstudie mit 367 Patienten.

BACKGROUND: In general, pediatric spinal injuries are rare. No reliable data on the epidemiology of spinal injuries in pediatric patients in Germany are available. Especially in pediatric patients, for whom the medical history, clinical examination and the performance of imaging diagnostics are difficult to obtain, all available information on a spinal injury must be taken into account. OBJECTIVE: The aim of this study was to provide epidemiological data for pediatric patients with spinal trauma in Germany in order to enhance future decision-making for the diagnostics and treatment of these patients. MATERIAL AND METHODS: Within the framework of a national multicenter study, data were retrospectively obtained from 6 German spine centers for 7 years between January 2010 and December 2016. In addition to the demographic data, the clinical databases were screened for specific trauma mechanisms, level of injury as well as accompanying injuries. Furthermore, diagnostic imaging and the treatment selected were also analyzed. RESULTS: A total of 367 children (female: male = 1:1.2) with a total of 610 spinal injuries were included in this study. The mean age was 12 years (±3.5 years). The most frequent trauma mechanisms were falls from <3 m and traffic accidents. The imaging diagnostics were only rarely carried out with the child under anesthesia. Younger children (0-9 years old) suffered more injuries to the cervical spine, whereas injuries to the thoracic and lumbar spine were more frequently found in older children (>10 years old). The children frequently showed accompanying injuries to the head and the extremities. Accompanying spinal injuries mostly occurred in adjacent regions and only rarely in other regions. Around 75% of the children were treated conservatively. CONCLUSION: The results were different from the knowledge obtained from adult patients with spinal trauma and describe the special circumstances for pediatric patients with spinal trauma. Despite certain limitations these facts may help to enhance future decision-making for the diagnostics and treatment of these patients.

[Posttraumatic deformity of the thoracolumbar spine]. / Posttraumatische Fehlstellungen der Brust- und Lendenwirbelsäule.

Posttraumatic kyphotic deformities of the thoracolumbar spine may result in significant clinical complaints. If conservative treatment is not successful, surgical correction of the kyphosis becomes an option. In contrast to degenerative deformities, posttraumatic kyphotic deformities are usual limited to few segments and can be treated with shorter constructs. The surgical strategy depends on the rigidity and the localization of the posttraumatic kyphotic deformity. In this respect purely posterior approaches and combined posteroanterior surgical approaches are available each with different advantages and disadvantages.

Recommendations for the Diagnostic Testing and Therapy of Atlas Fractures. / Empfehlungen zur Diagnostik und Therapie oberer Halswirbelsäulenverletzungen: Atlasfrakturen.

In a consensus process with four sessions in 2017, the working group on "the upper cervical spine" of the German Society for Orthopaedic and Trauma Surgery (DGOU) formulated "Therapeutic Recommendations for the Diagnosis and Treatment of Fractures to the Upper Cervical Spine", incorporating their own experience and current literature. The following article describes the recommendations for the atlas vertebra. About 10% of all cervical spine injuries include the axis vertebra. The diagnostic process primarily aims to detect the injury and to determine joint incongruency and integrity of the atlas ring. For classification purposes, the Gehweiler classification and the Dickman classification are suitable. The Canadian c-spine rule is recommended for clinical screening for c-spine injuries. CT is the preferred imaging modality; MRI is needed to determine the integrity of the Lig. transversum atlantis in complete atlas ring fractures. Conservative treatment is appropriate in very many atlas fractures. Surgical treatment is recommended in existing or potential joint incongruity or instability, which are frequently seen in Gehweiler IIIB or Gehweiler IV fractures. Posterior atlanto-axial stabilisation and fusion using transarticular screws or an internal fixator are regarded as a gold standard in the majority of surgical cases. Especially in young patients, the possibility of isolated atlas osteosynthesis should be checked. A possible option for Gehweiler IV fractures is halo-fixation with mild distraction for ligamentotaxis. Secondary dislocation should be checked for frequently. Involvement of the occipito-atlantal joint complex requires stabilisation of the occiput as well.

Two-Nation Comparison of Classification and Treatment of Subaxial Cervical Spine Fractures: An Internet-Based Multicenter Study Among Spine Surgeons.

BACKGROUND: To date, no evidence-based treatment algorithm is available for fractures of the subaxial spine. The aim of the present study was to assess and compare the management strategy for traumatic subaxial fractures among German and Dutch spine surgeons. METHODS: In our web-based multicenter study, German and Dutch spine surgeons evaluated the computed tomography data of traumatic subaxial fractures (C3-C7). Supplementary case-specific information was provided. The fractures were classified using the AO spine classification. Next, 9 questions concerning the treatment algorithm were evaluated. Data were analyzed using SPSS. Statistical significance was defined as P < 0.05. RESULTS: Ten surgeons (5/country) evaluated 31 cases (310 votes). The fractures were classified as AO type A in 37% (114 votes), type B in 50% (155 votes), and type C in 13% (41 votes). German spine surgeons had a lower threshold concerning the indication for surgical treatment (German, 94.2% vs. Netherlands, 58.1%; P < 0.05). A consensus was present for operative stabilization for type B and C injuries, but a discrepancy was found in the therapeutic algorithm for type A fractures. The most significant difference was seen in the treatment of type A2 and A3 fractures (surgery for type A2/A3 fracture: German, 92.9% vs. Netherlands, 5.3%; P < 0.05). CONCLUSION: We found a consensus for the stabilization of AO type B and C fractures but country-specific differences in the treatment of type A fractures, especially for A2 and A3 fractures. Further evidence is necessary to ensure more consistent international treatment strategies.

The C2-Pars Interarticularis Screw as an Alternative in Atlanto-Axial Stabilization. A Biomechanical Comparison of Established Techniques.

AIM: To compare four different atlantoaxial stabilization techniques. MATERIAL AND METHODS: Eight human cervical spines (segments C0-C3) were tested in flexion/extension, lateral bending and axial rotation. Range of Motion (ROM) at a 1.5 Nm load was recorded. After native testing, the Harms (HARMS), pars screw (PARS), intralaminar screw (INTRA) and anterior transarticular screw (ATA) constructs were applied in a random order. RESULTS: FLEXION/EXTENSION: mean ROM (±SD) in native state was 15.9° (± 7.6°); HARMS 3.6° (± 2.0°); INTRA 5.5° (± 2.7°); PARS 2.8° (± 1.6°); ATA 3.7° (± 1.3°). A significant difference was found for all techniques compared to the native spine. LATERAL BENDING: ROM in native state was 3.2° (± 1.9°); HARMS 1.4° (± 0.4°); INTRA 2.5° (± 1.4°); PARS 1.3° (± 0.7°); ATA 0.9° (± 0.6°). There were no significant differences compared to native spine, although ATA and PARS showed a strong tendency. INTRA had a significantly higher ROM than ATA. AXIAL ROTATION: ROM in native state was 15.7° (± 6.6°); HARMS 1.5° (± 0.7); INTRA 2.7° (± 2.1°); PARS 1.7° (± 0.7); ATA 1.1° (± 0.3°). All instrumentation techniques significantly reduced ROM; there was no significant difference between the techniques. All instrumentation techniques were able to reduce ROM for most of the motions. The differences between the techniques were small. Nevertheless, the intralaminar screw showed deficits in lateral bending. CONCLUSION: Screw positioning seems to be of minor influence on stability in atlantoaxial stabilization. Therefore, the pars screw is a sound alternative to the established techniques from a biomechanical point of view. Anatomical considerations for screw placement should be kept in mind as a superior priority.

Treatment of Axis Ring Fractures: Recommendations of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU).

STUDY DESIGN: Narrative literature review and expert recommendation. OBJECTIVE: To establish treatment recommendations for axis ring fractures based on the knowledge of the experts of the Spine Section of the German Society for Orthopaedics and Trauma. METHODS: This recommendation summarizes the knowledge of the experts of the Spine Section of the German Society for Orthopaedics and Trauma with regard to the treatment of axis ring fractures based on a narrative literature review. RESULTS: Typical "hangman's fractures" with bilateral separation of the neural arch from C2 and atypical "hangman's fractures" with irregular fracture morphology are described. Computed tomography is the "gold" standard used to detect and analyse these fractures adequately. Furthermore, the detection of vertebral artery integrity is necessary. To classify axis ring fractures, the Levine-Edwards or Josten classification is recommended. In particular, the integrity of the C2/3 disc and the integrity of the anterior longitudinal ligament are used to determine the treatment strategy. While Levine-Edwards type I and type IIA (Josten type 1 and 2) fractures should be treated conservatively, Levine type II and type III (Josten type 3 and 4) fractures should be treated operatively. Levine-Edwards type II fractures will be predominately treated by anterior C2/3 fusion. Levine-Edwards type III fractures have to be primary reduced, if an anterior fusion is planned (anterior cervical discectomy and fusion [ACDF] C2/3). If a closed reduction of a type III fracture is impossible, an open reduction and posterior fixation/fusion is the treatment of choice. CONCLUSION: Conservative treatment is predominantly reserved for Levine-Edwards I and IIA fractures. Operative treatment should be performed in case of Levine-Edwards II and III fractures.