Benjamin König

Balloon osteoplasty—a new technique for reduction and stabilisation of impression fractures in the tibial plateau: A cadaver study and first clinical application

PurposeFractures of the tibial plateau are among the most severe injuries of the knee joint and lead to advanced gonarthrosis if the reduction does not restore perfect joint congruency. Many different reduction techniques focusing on open surgical procedures have been described in the past. In this context we would like to introduce a novel technique which was first tested in a cadaver setup and has undergone its successful first clinical application.MethodsSince kyphoplasty demonstrated effective ways of anatomical correction in spine fractures, we adapted the inflatable instruments and used the balloon technique to reduce depressed fragments of the tibial plateau.ResultsThe technique enabled us to restore a congruent cartilage surface and bone reduction.ConclusionsIn this technique we see a useful new method to reduce depressed fractures of the tibial plateau with the advantages of low collateral damage as it is known from minimally invasive procedures.

Auswirkungen einer Beckenringverletzung auf die Erwerbsfähigkeit

Introduction: Pelvic ring injuries occur in 3-8 % of patients with fractures. They are rare, with an annual incidence of only 19-37 per 100,000 people annually. There have been publications on the generation of these injuries, as well as their diagnosis and treatment concepts, but there is little information on how these injuries impact the ability to work. Patients: The study covered all hospitalised patients between January 2003 and December 2011 with a pelvic ring injury, who had already been included in the data collection of the AG Becken III and who had had a work-related accident. Data acquisition was completed 12 months after the first cover letter. Data collection was supported by the statutory accident insurance institutions. Responses to the following questions were collected: Results: During the time period, 835 patients were admitted to our hospital with an injury to the pelvic ring or acetabulum. 632 patients (75.7 %) had a pelvic ring injury. 95 patients had a work-related accident, for which 67 records (70.5 %) could be evaluated. Seven patients were in retirement at the time. The average age was 48 years. In the patient population, we identified 9 type A, 16 type B and 42 type C injuries. The mean duration of incapacity for work was 9.5 months. 36 patients were able to return to their old work again, 22 patients did not. For two of these patients, this was due to cerebral haemorrhage. The mean reduction in earning capacity at the 1st and 2nd pension reports was 28 %. The individual rating of the degree of trauma lay between 0 % (B2.1) to 60 % (C1.2). Subgroup analysis was not performed, due to the small number of patients and their lack of homogeneity. As only hospitalised patients were included in the study group, there was excessive accumulation of pelvic B and C fractures in the patient group. The study shows that pelvic ring injuries can have a significant impact on the duration of the incapacity and the ability to work.

Safe surgical technique: cement-augmented pedicle screw instrumentation and balloon-guided kyphoplasty for a lumbar burst fracture in a 97-year-old patient

BackgroundDuring the last few years, an increasing number of unstable thoracolumbar fractures, especially in elderly patients, has been treated by dorsal instrumentation combined with a balloon kyphoplasty. This combination provides additional stabilization to the anterior spinal column without any need for a second ventral approach.Case presentationWe report the case of a 97-year-old male patient with a lumbar burst fracture (type A3-1.1 according to the AO Classification) who presented prolonged neurological deficits of the lower limbs - grade C according to the modified Frankel/ASIA score. After a posterior realignment of the fractured vertebra with an internal screw fixation and after an augmentation with non-absorbable cement in combination with a balloon kyphoplasty, the patient regained his mobility without any neurological restrictions.ConclusionEspecially in older patients, the presented technique of PMMA-augmented pedicle screw instrumentation combined with balloon-assisted kyphoplasty could be an option to address unstable vertebral fractures in “a minor-invasive way”. The standard procedure of a two-step dorsoventral approach could be reduced to a one-step procedure.

Insuffizienzfrakturen des Beckenrings

ZusammenfassungHintergrundDie Veränderung der Altersstruktur in unserer Gesellschaft führt zwangsläufig auch zu einem Anstieg der spezifischen Erkrankungen und Verletzungen der älteren Generation. So nehmen der prozentuale Anteil an osteoporotischen und Ermüdungsfrakturen insgesamt und somit auch die absolute Anzahl der Insuffizienzfrakturen des Beckenrings zu. Ursachen von BeckenringfrakturenWährend beim jungen Menschen eine Beckenringfraktur meist die Folge eines Hochrasanztraumas ist, kommt es im Alter immer häufiger bereits bei Niedrigenergietraumen oder gar ohne Trauma zu dieser Verletzungsform, welche dann im Sinne einer Insuffizienzfraktur zu werten ist. Diagnostik und TherapieOft ist die konventionelle radiologische Diagnostik allein nicht ausreichend, sodass sie durch schnittbildgebende Verfahren ergänzt werden muss. Die Problematik dieser Frakturen wird in der konventionellen Frakturklassifikation nicht ausreichend abgebildet. Die Therapieformen müssen stärker als bei den klassischen Frakturformen an den Allgemeinzustand und die Lebensumstände des Patienten angepasst werden und auch die deutlich verminderte Haltekraft der Osteosynthesen im veränderten Knochen berücksichtigen.AbstractBackgroundThe changing age distribution in our society inevitably also leads to an increase in age-specific injuries. As a result, the percentage of osteoporotic and fatigue fractures and the absolute number of insufficiency fractures of the pelvic ring are increasing. Causes of pelvic ring fracturesWhile pelvic ring injuries in younger patients are mainly caused by high velocity accidents, the reason for pelvic fractures in elderly patients is often a trivial fall to the floor or even no impact at all. These kinds of injuries are consequently assessed as insufficiency fractures. Diagnosis and therapyConventional x-rays of the pelvic ring are frequently not able to reveal the injury; therefore, additional diagnostic methods (e.g., CT scan or even MRI) are recommended. The established classifications for pelvic ring fractures do not sufficiently reflect the complexity of these injuries. Therapy must be chosen based on the general condition and living environment of the elderly patient. Reduced bone quality leads to problems with implants such as early loosening of conventional screws and must be considered when planning operative stabilization.

Computer assisted evaluation of plate osteosynthesis of diaphyseal femur fracture considering interfragmentary movement: a finite element study.

Abstract A semi-automated workflow for evaluation of diaphyseal fracture treatment of the femur has been developed and implemented. The aim was to investigate the influence of locking compression plating with diverse fracture-specific screw configurations on interfragmentary movements (IFMs) with the use of finite element (FE) analysis. Computed tomography (CT) data of a 22-year-old non-osteoporotic female were used for patient specific modeling of the inhomogeneous material properties of bone. Hounsfield units (HU) were exported and assigned to elements of a FE mesh and converted to mechanical properties such as the Young’s modulus followed by a linear FE analysis performed in a semi-automated fashion. IFM on the near and far cortex was evaluated. A positive correlation between bridging length and IFM was observed. Optimal healing conditions with IFMs between 0.5 mm and 1 mm were found in a constellation with a medium bridging length of 80 mm with three unoccupied screw holes around the fracture gap. Usage of monocortical screws instead of bicortical ones had negligible influence on the evaluated parameters when modeling non-osteoporotic bone. Minimal user input, automation of the procedure and an efficient computation time ensured quick delivery of results which will be essential in a future clinical application.

Klinische Erfahrungen, Indikationen und Grenzen – Navigation in der Becken- und Acetabulumchirurgie

Der Einsatz chirurgischer Navigationssysteme hat sich in Orthopadie und Unfallchirurgie fur Anwendungen wie die Knie-TEP-Implantation oder dorsale Stabilisierungen an der Wirbelsaule bewahrt. An Becken und Acetabulum steht insbesondere die perkutane navigierte SI-Schraubenplatzierung als etabliertes Verfahren im Vordergrund. Dazu wird insbesondere die C–Arm-Navigation mit 2–D- oder 3–D-Bildwandlern eingesetzt. Sie haben den Vorteil, direkt intraoperativ die Akquisition von Navigationsdaten zu gestatten und keine praoperative Verarbeitung von Bilddaten fur die Navigation zu benotigen. Mit diesen Systemen lasst sich trotz komplexer Anatomie des Beckens nach erfolgter Reposition eine prazise Schraubenpositionierung durchfuhren. Fur seltenere Indikationen wie Tumorresektionen wird neben o. g. Verfahren auch die CT-basierte Navigation verwendet, welche zwar keine Erstellung von Bilddaten im OP gestattet, jedoch eine Darstellung eines groseren Bilddatenvolumens und das Matching mit anderen Bildmodalitaten (MRI, PET CT) bei der prazisen Planung der Resektionsebenen ermoglicht.

Periazetabuläre Navigation@@@Periacetabular navigation

ZusammenfassungNachdem Azetabulumfrakturen – historisch gesehen – lange Zeit ausschließlich konservativ behandelt worden waren, folgte mit der Einführung von Klassifikationen und der Definition von Indikationen eine Phase der komplexen anatomischen Rekonstruktionen über erweiterte Operationszugänge. Die aktuelle Entwicklung führt hin zu minimalinvasiven Operationstechniken unter Anwendung intraoperativer 3D-Bildgebung mit Navigation. Damit sollen die Zugangsmorbidität gesenkt und die chirurgische Präzision erhöht werden. Bei entsprechender Bildqualität setzt sich die bildwandlergestützte 3D-Navigation als Verfahren der Wahl nach Frakturrepositionen sowie für minimalinvasive Operationstechniken im Vergleich zur computertomographiebasierten und 2D-Bildwandler-basierten Navigation zunehmend durch. In Kombination mit anderen modernen Verfahren werden auch neue Operationstechniken ermöglicht.AbstractFollowing a period of conservative treatment of acetabular fractures in the past, the use of classifications and defined acetabular surgery indications was introduced because of an increasing number of extended surgical approaches for operative stabilization of acetabular fractures. This development has enabled minimally invasive procedures using three-dimensional (3D) visualization and navigation techniques in the operating room (OR), with the expectation of reduced intraoperative morbidity and optimized surgical precision. Most common in acetabular navigation is 3D C-arm-based navigation, which has enabled new techniques in combination with other modern OR systems. In special cases, techniques based on computed tomography and 2D C-arms are still used.