Regional Variations in the Intra- and Intervertebral Trabecular Microarchitecture of the Osteoporotic Axial Skeleton with Reference to the Direction of Puncture.

BACKGROUND: Trabeculae in vertebral bodies are unequally distributed within the cervical spine (CS), the thoracic spine (TS), and lumbar spine (LS). Such structures are also unequally distributed within the individual vertebrae. Exact knowledge of the microstructure of these entities could impact our understanding and treatment of fractures caused by osteoporosis and possibly improve surgical approaches. Appropriate investigations could help clarify the pathomechanisms of different forms of osteoporotic vertebral fractures, as well as different changes in morphological findings like the trabecular bone score (TBS). In the present study, we applied punctures to the craniocaudal and ventrocaudal directions and obtained cylinders of cancellous bone from the central portions and marginal regions of cervical vertebrae 5 and 6, thoracic vertebrae 8 and 12, and lumbar vertebrae 1 and 3. We systematically analyzed these samples to determine the bone volume fraction, trabecular thickness, separation, connectivity density, degree of anisotropy, and structure model index. METHODS: Using an 8-gauge Jamshidi needle, we obtained samples from three quadrants (Q I: right margin; Q II: central; Q III: left margin) in the frontal and transverse plane and prepared these samples with a moist cloth in a 1.5 mL Eppendorf reaction vessel. The investigations were performed on a micro-CT device (SKYSCAN 1172, RJL Micro & Analytic Company, Karlsdorf-Neuthard, Germany). All collected data were analyzed using the statistical software package SPSS (version 24.0, IBM Corp., Armonk, NY, USA). Student's t test, the Wilcoxon-Mann-Whitney test, the Chi-squared test, and univariate analysis were used for between-group comparisons. The selection of the test depended on the number of investigated groups and the result of the Shapiro-Wilk test of normal distribution. In the case of statistically significant results, a post hoc LSD test was performed. RESULTS: In total, we obtained 360 bone samples from 20 body donors. The craniocaudal puncture yielded data of similar magnitudes for all investigated parameters in all three quadrants, with the highest values observed in the CS. Comparisons of the ventrodorsal and craniocaudal microstructure revealed a significantly lower trabecular density and a significantly higher degree of anisotropy in the craniocaudal direction. CONCLUSIONS: The results presented different distributions and behaviors of trabecular density, with lower density in the mid-vertebral region over the entire breadth of the vertebrae. Reduced trabecular density caused a higher degree of anisotropy and was, therefore, associated with a lower capacity to sustain biomechanical loads. Fractures in fish vertebrae were easily explained by this phenomenon. The different changes in these structures could be responsible, in part, for the changes in the TBS determined using dual-energy X-ray absorptiometry. These results confirm the clinical relevance of the TBS.

Functional assessment and outcome following surgical treatment of displaced tibial plateau fractures: a retrospective analysis.

PURPOSE: Patients with tibial plateau fractures (TPF) are at risk of long-term hampered bipedal locomotion. A retrospective single-center study using patient-related outcome measures and a sophisticated assessment of walking abilities was conducted. METHODS: Adults receiving surgical treatment of an isolated TPF between January 2012 and December 2016 received the KOOS questionnaire together with the invitation for an extensive follow-up examination on the clinical outcome including standardized assessment of the walking abilities (loadsol® system). Outcome was assessed relative to the severity of the injury or time to follow-up. Fractures were classified according to AO/OTA and Luo, respectively. RESULTS: 58 out of 132 eligible patients filled in the questionnaire and participated at a median follow-up of 3.05 years after injury. For the categories "pain", "mobility", and "daily life activities", all patients were rather satisfied and this was virtually not related to the time between fracture and assessment. Relevant limitations were reported for "sports and recreational activities" and "quality of life". Loading of the previously fractured leg was most evidently changed on stairs and outdoor walking. Outcome was not related to either fracture type severity or time from injury. CONCLUSION: Outcome after an isolated TPF is neither related to fracture type, severity of the fracture nor time from injury. Simple gait analysis techniques relying on different tasks appear to yield a more sophisticated image on functional deficits after TPF than classical exam of ground-level walking and correlate quite well with validated patient-related outcome measures as the KOOS.

[Sacral H-shaped fractures between traumatic, insufficiency and fatigue fractures : Similarities, differences and controversies]. / Die Sakrum-H-Fraktur zwischen traumatischer, Insuffizienz- und Ermüdungsfraktur : Gemeinsamkeiten, Unterschiede und Kontroversen.

In the basic entirety of stress fractures, insufficiency fractures are defined as fractures caused by prolonged normal or physiological loading of a bone with insufficient elastic resistance. This clearly distinguishes it from fatigue fractures, in which excessive loads are continuously applied to a bone with normal elastic resistance. According to Pentecost (1964) both entities of stress fracture result from "the inherent inability of the bone to withstand stress applied without violence in a rhythmical, repeated, subthreshold manner". This distinguishes them from acute traumatic fractures. In the clinical routine these differences are not always so clearly presented. The example of the H­shaped sacral fracture is used to illustrate the relevance of a clear terminology. In this context, current controversies in the treatment of sacral insufficiency fractures are discussed.

Current concepts review. Management of proximal tibial fractures.

The management of proximal tibial fractures has evolved significantly in recent years. While the main goals of treatment - stability, restoration of the mechanical axis, and smooth articular surfaces - remain the same, methods have advanced substantially. In diagnostics, technical progress in CT and MR imaging has led to a better three-dimensional understanding of the injury. Newly developed classification systems such as the three-column concept of Luo et al. and the 10-segment concept of Krause et al. take this into account. Accordingly, there is a trend towards tailored approaches for particular fracture localizations. Parallel to this development, there is increasing evidence of the advantages of arthroscopically assisted surgical procedures. This Current Concepts article reviews classifications, diagnostics, treatment options as well as complications in fractures of the proximal tibia.

Late diagnosis of pedicle screw malplacement with perforation of the thoracic aorta after posterior stabilization in a patient with multiple myeloma: case report.

STUDY DESIGN: A case report. OBJECTIVE: To demonstrate delayed diagnosis of screw malpositioning with perforation of the thoracic aorta after posterior stabilization of a Th7-vertebral collapse due to multiple myeloma. Relevant diagnostic and therapeutic strategies are outlined in the context of a rather unfortunate series of interventional events. SUMMARY OF BACKGROUND DATA: Pedicle screw instrumentation has become a well-established standard in the surgical treatment of various disorders of the spinal column. Particularly at the upper-thoracic level, the close anatomic relationship of the spine to the aorta places it and other major structures at high risk. Although iatrogenic vascular injuries are rare, a few cases have been described. METHODS: A 64-year-old female patient remarked progressive back pain after 2 years of uneventful recovery from a multilevel posterior stabilization by pedicle screw and rod instrumentation because of an osteolytic collapse of the Th7 vertebra. The subsequent computed tomographic scan demonstrated kyphotic deformity of the thoracic spine with transspinal and periaortic screw malplacement. RESULTS: The revision strategy was an interdisciplinary single session two-phase operation. The primary phase included a left-sided thoracotomy, mobilization of the thoracic aorta, and posterior implant removal under vascular monitoring in right lateral position. The initially planned corporectomy of Th7 and subsequent vertebral body replacement by cage implantation via the anterior approach was dismissed because of critical tissue adhesions of the thoracic aorta to the anterior vertebral column. Finally, the thoracotomy was closed, the patient transferred into prone position and stabilized by a multilevel posterior reinstrumentation under fluoroscopy guidance. CONCLUSION: Although the clinical course in malpositioned pedicle screw instrumentation may stay unremarkable, this case illustrates that in a proven injury to the thoracic aorta revision is mandatory to prevent further vascular damage. The appropriate strategy demands exact and provident planning using a preferably interdisciplinary approach.

Clinical diagnosis versus autopsy findings in polytrauma fatalities.

OBJECTIVES: The aim of the study was to determine if differences in clinical diagnosis versus autopsy findings concerning the cause of death in polytrauma fatalities would be detected in 19 cases of fatal polytrauma from a Level 1 trauma centre. METHODS: Clinical diagnoses determining the cause of death in 19 cases of fatal polytrauma (2007 - 2008) from a Level 1 trauma centre were correlated with autopsy findings. RESULTS: In 13 cases (68%), the clinical cause of death and the cause of death as determined by autopsy were congruent. Marginal differences occurred in three (16%) patients while obvious differences in interpreting the cause of death were found in another three (16%) cases. Five fatalities (three with obvious differences and two with marginal differences) were remarked as early death (1-4 h after trauma) and one fatality with marginal differences as late death (>1 week after trauma). Obvious and marginal discrepancies mostly occurred in the early phase of treatment, especially when severely injured patients were admitted to the emergency room undergoing continued cardiopulmonary resuscitation, i. e. limiting diagnostic procedures, and thus the clinical cause of death was essentially determined by basic emergency diagnostics. CONCLUSIONS: Autopsy as golden standard to define the cause of death in fatal polytrauma varies from the clinical point of view, depending on the patient's pre-existing condition, mechanism of polytrauma, necessity of traumatic cardiopulmonary resuscitation, survival time, and thus the possibility to perform emergency diagnostics. An autopsy should be performed at least in cases of early fatal polytrauma to help establishing the definite cause of death. Moreover, autopsy data should be included in trauma registries as a quality assessment tool.