J. von Recum

Die intraoperative 3D-C-Bogen-Anwendung

Mobile C-arms with the option of 3D imaging like the Iso-C(3D) allow for intraoperative 3D visualization of anatomical areas with complex three-dimensional structures like articular surfaces. In an 8-year period we performed 1,841 intraoperative control scans following osteosynthesis. Among these patients we registered the number of intraoperative adjustments of fracture reduction and implant position in correlation to the area of surgery. The majority of intraoperative examinations in 1,841 patients was performed in fractures of the calcaneus (20.5%) and the upper ankle joint (13.2%). Altogether we improved the reduction or the implant position intraoperatively in 21.5%. The majority of intraoperative revisions was seen in osteosynthesis of the calcaneus (40.3%), the upper ankle joint (30.9%) and fractures of the distal tibia (29%). The rate of revisions over the time was very stable. Intraoperative need for revision of reduction or implant position is not a rare phenomenon in our experience. Intraoperative 3D imaging is a valid tool to recognize and adjust suboptimal reduction or implant positioning. Intraoperative 3D imaging can improve the quality of osteosynthesis especially in fractures of joints and complex anatomical areas.

Postoperative Torsionsdifferenz nach unaufgebohrter antegrader Marknagelosteosynthese des Femurs: eine retrospektive 5-Jahres-Analyse

BACKGROUND Minimally invasive treatment of diaphyseal femur fractures (DFF) with closed reduction and intramedullary nailing is a well established procedure. However, a femoral malrotation after intramedullary nailing is considered to be a substantial problem. Studies have described femoral malrotation (FMR) in 17-35 % after this procedure. Computed tomography (CT) of both femora is accepted as an objective, reproducible measurement method to determine a postoperative femoral malrotation. An anatomic reposition of the centreline of the femur remains of high importance since a malrotation > 15° can lead to a significant limitation of the range of motion (ROM) and to clinical symptomatic constraints. PATIENTS/MATERIAL AND METHODS Between July 2007 and December 2011 patients with unilateral DFF were treated with closed reduction and intramedullary nailing. Exclusion criteria were defined as bilateral or prior treatment for femoral fractures, open epihyseal plate or pregnancy. In all cases a postoperative CT scan of the femora was conducted to analyse a femoral malrotation. The indication for a correction was posed in cases of a malrotation > 15°. The data were not randomised and evaluated retrospectively. RESULTS AND CONCLUSION In total 94 patients with unilateral DFF were included. 21 female and 73 male with an average age of 33.15 ± 14.04 years (range 14-94). In the postoperative CT scan an average FMR of 11.58 ± 9.41° (range 0-44°) was determined. In 15 cases (15.95 %), 10 male (13.7 %) and 5 female (23.81 %) a FMR > 15° (average: 23.66 ± 5.74°) was noticed. A subsequent surgery with a correction in average of 17.53 ± 6.83° was performed. After the correction the malrotation averaged 6.07 ± 5.61°. The results support the existing data that the treatment of DFF with closed reduction and intramedullary nailing may lead to a significant femoral malrotation despite a precise intraoperative monitoring. The data demonstrate that nearly 15 % of all patients appear after closed reduction and intramedullary nailing with a femoral malrotation greater than 15°. A routinely utilised postoperative CT scan provides additional information to discover an occult malrotation. CONCLUSION In spite of diligent attendance to the femoral torsion intraoperatively in DFF a significant femoral malrotation may result after closed reduction and intramedullary nailing. To prevent a limitation of ROM and clinical constraints a routinely performed postoperative CT scan with a adequate surgical correction is recommended.

Bestimmung des Femur-Antetorsionswinkels mit einem fluoroskopiebasierten optoelektronischen Navigationssystem

According to the literature, differences in torsion of 15 degrees and more develop in 20-30% of cases after intramedullary nailing of femoral shaft fractures. A computer-assisted method makes it possible to determine the antetorsion angle during surgery. In this experimental study, the precision of the measurements obtained with the navigation system were checked with a femur model and compared with a CT reference method. The measurements are carried out on a femur model that is equipped with a rotation device in the middle of the shaft. Nine reproducible angles can be set. Two investigators each conduct the measurements of the antetorsion angle ten times. A comparison is drawn between the absolute values of the antetorsion angle measured and the difference values of the adjoining positions. When comparing the absolute values of the navigation and reference systems, the mean deviations of both methods are around 1 degrees (0.35; 1.75) and comparing the differences 0.5 degrees (-0.2; 1.17). The maximum deviation of the absolute values of the CT reference method amounts to 6.4 degrees . Under experimental conditions, measurement of the femoral antetorsion angle proved to be sufficiently precise for clinical specifications in comparison to a CT reference method.

Cystic pseudotumours in both upper ankle joints in gouty arthritis

This case demonstrates a yet unreported clinical entity of bilateral tophaceous cystic lesions of the tibiotalar joints of an 37-year-old white male who presents with moderate painful swelling in both upper ankle joints for 2 years. Radiodiagnostic studies show cystic lesions in both upper ankle joints and the right talus considering neoplastic processes in the differential diagnosis. The incisional biopsy reveals chalk-like material of the intraosseous lesions which was pathognomonic for tophaceous gout. Antihyperuricemic medication led to a stagnation of growth of the lesions without a sign of osseous remodeling. However, due to limitation of discomfort, personal preferences and a lack of surgical options conservative treatment was maintained.

Stiffness measurement of the neocallus with the Fraktometer FM 100

Introduction: The assessment of fracture healing is subjective, and neither radiology nor manual examination allows a reliable determination of bone healing. Fracture healing control in the treatment of tibia shaft fracture with external fixator by a stiffness measurement system (Fraktometer FM 100®) is known from clinical studies. The purpose of this study was to follow stiffness control at external fixator in healing of callotasis with the stiffness measurement system. Materials and methods: From 1994 to 1997 stiffness measurements with the described system (Fraktometer FM 100) were performed in the BG-Clinic Ludwigshafen to assess the healing course in 11 cases of callotasis at lower limb. Results: In ten cases, regular healing could be followed by signal decrease; in one case, a persistent signal without tendency to decrease was able to reveal callotasis failure at an early point of time. The investigation could also show the importance of bending stiffness control. One case of late axis deformation after fixator removal occurred because of disregarding delayed bending signal decrease. Conclusion: Measurements of the external fixator’s stiffness after callotasis can provide useful additional information for further treatment strategy.

Rekonstruktion posttraumatischer Fehlstellungen des Rückfußes

ZusammenfassungHintergrundNach Verletzungen der Füße kommt es häufig aufgrund von Fehlstellungen, schmerzhaften Pseudarthrosen und Instabilitäten zu bleibenden Funktionsbeeinträchtigungen. Ursachen für korrekturbedürftige Fußfehlstellungen sind übersehene oder inadäquat therapierte Verletzungen. Komplizierte postoperative Verläufe mit posttraumatischen Arthrosen, Infekten, Osteonekrosen, ausbleibenden knöchernen Heilungen oder muskulären Imbalancen können auch nach initial korrekter Behandlung zu korrekturbedürftigen Fehlstellungen führen. KorrektureingriffeKorrekturmaßnahmen müssen alle Funktionen des Fußes berücksichtigen. Das Augenmerk muss dabei insbesondere auf die Achsausrichtung des Rückfußes und die Koppelung des Vorfußes gelegt werden. Idealerweise werden Korrektureingriffe vor Auftreten von Anschlussarthrosen benachbarter Gelenke durchgeführt. Zur Wiederherstellung der Funktion des Fußes sollten Arthrodesen auf die unmittelbar betroffenen Gelenke beschränkt bleiben. Deformierende Kräfte der motorisch überwiegenden Muskelgruppen müssen neutralisiert werden, um erneute Deformitäten zu vermeiden. AbstractBackgroundFoot injuries often lead to residual functional disabilities due to malalignment, painful pseudoarthrosis and instability. The reasons for foot malpositioning which need correction are overlooked or inadequately treated injuries. Complicated postoperative courses with posttraumatic arthrosis, infections, osteonecrosis, delayed bone healing or muscular imbalance can also lead to deformities needing correction even after initially correct treatment.Corrective interventionsCorrective measures must take all functions of the foot into consideration. Attention must be paid in particular to the axis orientation of the hindfoot and coupling of the forefoot. Ideally corrective interventions should be carried out before the occurrence of arthrosis in neighboring joints. For reconstruction of the function of the foot arthrodesis should be limited to immediately affected joints. Deforming forces of the muscle groups with mainly motor functions must be neutralized in order to avoid new deformities.

Frische Verletzung des OSG

ZusammenfassungVor Behandlung einer Sprunggelenkverletzung muss das gesamte Verletzungsausmaß erfasst werden. Dies ist nur bei entsprechenden Kenntnissen über die biomechanischen Grundlagen dieses komplexen Gelenks möglich. Bei der Diagnose kommt — neben Anamnese und klinischer Untersuchung — dem konventionellen Röntgen eine wesentliche Bedeutung zu. In besonderen Fragestellungen haben Funktionsaufnahmen und Schnittbilddiagnostik ihren Stellenwert. Die Einteilung der Sprunggelenkfrakturen nach Lauge-Hansen verbessert das Verständnis der Verletzungsabfolge und gibt entscheidende Hilfestellungen bei der Erfassung der ligamentären Begleitverletzungen. Besonderer Beachtung bedürfen die hochgradig instabilen Verletzungen vom Pronations-Eversions-Typ. Hier ist die Wiederherstellung der Syndesmose und damit die Stabilität der Malleolengabel Grundvoraussetzung für ein funktionell zufrieden stellendes Ergebnis. Die Einstellung der Fibula in die Inzisur ist technisch anspruchvoll, die Platzierung der Stellschraube beinhaltet Komplikationsmöglichkeiten. Die Überprüfung der exakten Einstellung ist mit dem konventionellen 2D-Bildverstärker nicht ausreichend sicher möglich. Hier ist ein Einsatz der Schnittbilddiagnostik zu fordern. Mit den 3D-Bildwandlern kann diese Überprüfung intraoperativ in ausreichend guter Qualität erfolgen. Damit wird der logistische Aufwand einer postoperativen CT-Diagnostik reduziert, und Revisionseingriffe werden vermieden.AbstractThe treatment of ankle injuries requires ascertainment of the total extent of the injury in each case. Knowledge of the basic biomechanical principles at play in this complex joint is essential. For the diagnosis, in addition to the history and the clinical examination, great importance also attaches to conventional X-ray examination. When there are particular problems with the diagnosis, functional X-rays and CT are valuable adjuncts. Classification of ankle fractures according to the Lauge-Hansen system enhances understanding of the course of the injury and is definitely helpful in the ascertainment of associated ligamentous injuries. Highly unstable injuries of the pronation–eversion type need particular attention. In these cases restoration of the syndemosis, and thus of the stability of the malleolar fork, is essential if a functionally satisfactory result is to be attained. It is technically difficult to insert the fibula in the incision, and placement of the positioning screw is also not without its pitfalls. It is not possible to check the precise alignment with an adequate level of certainty when a conventional 2D image intensifier is used. Diagnostic CT imaging should be prescribed for this purpose. Adequate quality can be achieved when this test is performed intraoperatively with a 3D image transformer. This makes it possible to avoid the logistical complications of postoperative diagnostic CT and also revision operations.

Rekonstruktion posttraumatischer Fehlstellungen

ZusammenfassungVerletzungen der Füße führen häufig aufgrund von Fehlstellungen, schmerzhaften Pseudarthrosen und Instabilitäten zu bleibenden Funktionsbeeinträchtigungen. Ursachen für korrekturbedürftige Fußfehlstellungen sind übersehene oder inadäquat therapierte Verletzungen. Komplizierte postoperative Verläufe mit posttraumatischen Arthrosen, Infekten, Osteonekrosen, ausbleibenden knöchernen Heilungen oder muskulären Imbalancen können auch nach initial korrekter Behandlung zu korrekturbedürftigen Fehlstellungen führen. Korrekturen müssen dabei alle Funktionen des Fußes berücksichtigen. Das Augenmerk muss insbesondere auf die Achsausrichtung des Rückfußes und die Koppelung des Vorfußes gelegt werden. Idealerweise werden Korrektureingriffe vor Auftreten von Anschlussarthrosen benachbarter Gelenke durchgeführt. Zur Wiederherstellung der Funktion des Fußes sollten Arthrodesen auf die unmittelbar betroffenen Gelenke beschränkt bleiben. Deformierende Kräfte der motorisch überwiegenden Muskelgruppen müssen neutralisiert werden, um erneute Deformitäten zu vermeiden. Der Beitrag gibt eine Übersicht über korrigierende Eingriffe am Rückfuß.AbstractFoot injuries often lead to permanent functional impairments due to malalignment, painful non-unions and instabilities. The causes of foot malalignment that need correction are overlooked or inadequately treated injuries. Complicated postoperative courses with posttraumatic arthrosis, infections, osteonecrosis, non-unions and muscular imbalance can lead to malalignment requiring correction even if the initial treatment was performed correctly. Corrective interventions must take all functions of the foot into consideration. Attention must particularly be paid to the axial alignment of the hindfoot and the coupling of the forefoot. Ideally, corrective interventions must be carried out before the occurrence of accompanying arthrosis of neighboring joints. For restoration of function of the foot arthrodesis should remain limited to the directly affected joint. Deforming forces of predominantly motor muscle groups must be neutralized in order to avoid new deformities. This article gives an overview of corrective interventions of the hindfoot.

Die intraoperative 3D-C-Bogen-Anwendung@@@Intraoperative 3D C-arm imaging: State of the art@@@State of the art

Mobile C-arms with the option of 3D imaging like the Iso-C(3D) allow for intraoperative 3D visualization of anatomical areas with complex three-dimensional structures like articular surfaces. In an 8-year period we performed 1,841 intraoperative control scans following osteosynthesis. Among these patients we registered the number of intraoperative adjustments of fracture reduction and implant position in correlation to the area of surgery. The majority of intraoperative examinations in 1,841 patients was performed in fractures of the calcaneus (20.5%) and the upper ankle joint (13.2%). Altogether we improved the reduction or the implant position intraoperatively in 21.5%. The majority of intraoperative revisions was seen in osteosynthesis of the calcaneus (40.3%), the upper ankle joint (30.9%) and fractures of the distal tibia (29%). The rate of revisions over the time was very stable. Intraoperative need for revision of reduction or implant position is not a rare phenomenon in our experience. Intraoperative 3D imaging is a valid tool to recognize and adjust suboptimal reduction or implant positioning. Intraoperative 3D imaging can improve the quality of osteosynthesis especially in fractures of joints and complex anatomical areas.

Bestimmung des Femur-Antetorsionswinkels mit einem fluoroskopiebasierten optoelektronischen Navigationssystem@@@Determining the femoral antetorsion angle with a fluoroscopy-based optoelectronic navigation system: Eine Genauigkeitsanalyse@@@A precision analysis

According to the literature, differences in torsion of 15 degrees and more develop in 20-30% of cases after intramedullary nailing of femoral shaft fractures. A computer-assisted method makes it possible to determine the antetorsion angle during surgery. In this experimental study, the precision of the measurements obtained with the navigation system were checked with a femur model and compared with a CT reference method. The measurements are carried out on a femur model that is equipped with a rotation device in the middle of the shaft. Nine reproducible angles can be set. Two investigators each conduct the measurements of the antetorsion angle ten times. A comparison is drawn between the absolute values of the antetorsion angle measured and the difference values of the adjoining positions. When comparing the absolute values of the navigation and reference systems, the mean deviations of both methods are around 1 degrees (0.35; 1.75) and comparing the differences 0.5 degrees (-0.2; 1.17). The maximum deviation of the absolute values of the CT reference method amounts to 6.4 degrees . Under experimental conditions, measurement of the femoral antetorsion angle proved to be sufficiently precise for clinical specifications in comparison to a CT reference method.