K. Wendl

Intraoperative Three-dimensional Imaging in the Treatment of Acute Unstable Syndesmotic Injuries

BACKGROUND Acute unstable syndesmotic ankle injuries are treated primarily by reduction and stabilization with a syndesmotic screw. Examination with fluoroscopy or standard radiographs may not provide reliable information about the quality of the reduction. There is evidence that intraoperative three-dimensional imaging can demonstrate a large proportion of malreductions. The aim of this study was to determine whether intraoperative three-dimensional imaging improves the detection of inadequate positioning of the distal aspect of the fibula in the tibiofibular incisura after syndesmotic screw insertion compared with the findings on standard intraoperative fluoroscopy. METHODS Of 2286 ankle fractures treated operatively from August 2001 to February 2011, 251 consecutive cases (11%) were identified in a retrospective chart review. All had an unstable syndesmosis and underwent syndesmosis stabilization on the basis of an intraoperative hook test. After fluoroscopy, an intraoperative three-dimensional scan was performed. The result of this scan was documented by the surgeon and analyzed retrospectively with regard to the incidence and nature of the need for intraoperative revisions. RESULTS The intraoperative three-dimensional scan altered the surgical outcome in eighty-two ankles (32.7%). In most ankles (seventy-seven; 30.7%), the reduction was improved, with the most common improvement being the alignment of the fibula in the tibiofibular incisura in sixty-four patients (25.5%) followed by correction of the fracture reduction in thirteen patients (5.2%). The other five alterations involved implant corrections. The most common malpositions requiring correction after insertion of a positioning screw, with or without additional fixation, were anterior displacement and internal rotation of the distal aspect of the fibula. CONCLUSIONS Following open reduction and internal fixation of an ankle fracture, the correct position of the syndesmosis cannot be evaluated reliably with use of conventional radiographs or intraoperative fluoroscopy. In view of the high proportion of positive findings in this study, we believe that any treatment of a syndesmotic injury should include intraoperative three-dimensional imaging or at least a postoperative computed tomography scan.

PERSONAL OBSERVATIONS, OPINIONS, AND APPROACHES TO CANCER OF THE PANCREAS AND PERIAMPULLARY AREA

This article reviews the diagnosis, staging, surgical, and adjuvant treatment of pancreatic and periampullary cancer based on personal experience covering 25 years. In spite of remarkable progress, especially in regard to staging and surgical treatment, the authors conclude that with the modalities currently available, timely diagnosis and definitive cure of this particular cancer is rare.

Computer-assisted LISS plate osteosynthesis of proximal tibia fractures: Feasibility study and first clinical results

Fluoroscopy is the most common tool for the intraoperative control of long-bone fracture reduction. Limitations of this technology include high radiation exposure for the patient and the surgical team, limited visual field, distorted images, and cumbersome verification of image updating. Fluoroscopy-based navigation systems partially address these limitations by allowing fluoroscopic images to be used for real-time surgical localization and instrument tracking. Existing fluoroscopy-based navigation systems are still limited as far as the virtual representation of true surgical reality is concerned. This article, for the first time, presents a reality-enhanced virtual fluoroscopy with radiation-free updates of in situ surgical fluoroscopic images to control metaphyseal fracture reduction. A virtual fluoroscopy is created using the projection properties of the fluoroscope; it allows the display of detailed three-dimensional (3D) geometric models of surgical tools and implants superimposed on the X-ray images. Starting from multiple registered fluoroscopy images, a virtual 3D cylinder model for each principal bone fragment is constructed. This spatial cylinder model not only supplies a 3D image of the fracture, but also allows effective fragment projection recovery from the fluoroscopic images and enables radiation-free updates of in situ surgical fluoroscopic images by non-linear interpolation and warping algorithms. Initial clinical experience was gained during four tibia fracture fixations that were treated by LISS (Less Invasive Stabilization System) osteosynthesis. In the cases operated on, after primary image acquisition, the image intensifier was replaced by the virtual reality system. In all cases, the procedure including fracture reduction and LISS osteosynthesis was performed entirely in virtual reality. A significant disadvantage was the unfamiliar operation of this prototype software and the need for an additional operator for the navigation system.

Intraoperative Three-Dimensional Imaging in the Treatment of Calcaneal Fractures

BACKGROUND Displaced intra-articular calcaneal fractures are frequently treated by open reduction and internal fixation. The usual intraoperative monitoring by means of fluoroscopy does not always provide complete intraoperative information for the surgeon. The aims of this study were to analyze the percentage of patients for whom intraoperative three-dimensional imaging leads to intraoperative revision and whether the avoidance of an intra-articular step or gap influences the clinical outcome. METHODS From August 2001 to June 2009, 377 consecutive, operatively treated calcaneal fractures were identified in a retrospective chart review. The results of the intraoperative three-dimensional scans were analyzed for the rate of and the reason for intraoperative revision. For the clinical evaluation, all patients with Sanders type-II and III fractures who were seen from October 2002 to January 2006 were included. When the outer shape of the calcaneus was successfully restored, the fractures were divided into two groups according to the reduction outcome for all joint surfaces (a step-off or gap of <2 mm or ≥2 mm). RESULTS The intraoperative revision rate was 40.3%. An additional fracture reduction was performed in 19.6% of the patients. Seventy-seven fractures were followed clinically. The American Orthopaedic Foot & Ankle Society (AOFAS) score indicated that postoperative joint surface congruence had a significant influence on clinical outcome, in both the bivariate and the multivariate analysis. The same relationship was shown between the joint surface congruence and the degree of osteoarthritis. CONCLUSIONS In many cases, intraoperative three-dimensional imaging identifies intra-articular incongruence and implants that are not detected by fluoroscopy. Due to the resulting options for better joint surface reconstruction, clinical outcomes may be improved, at times requiring repeat reduction, and posttraumatic osteoarthritis may be reduced.

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.

Predictors of a persistent dislocation after reduction of syndesmotic injuries detected with intraoperative three-dimensional imaging.

Background: In about 25% of cases, reduction of acute unstable syndesmotic injuries and stabilization with syndesmotic screws leads to an inadequate reduction. Conventional fluoroscopy does not provide reliable information about the reduction outcome. However, use of intraoperative 3D imaging can be more accurate. The purpose of this study was to identify predictors of inadequate reduction so that the need for intra- or postoperative 3D imaging could be assessed. Our hypothesis was that complex injuries of the syndesmosis present a higher risk of malreduction than simpler ankle fractures. Methods: From August 2001 to February 2011, 251 unstable syndesmotic injuries were treated from a total of 2286 ankle fractures. In 61 of these cases, malreduction of the fibula into the fibular notch was detected by intraoperative 3D imaging. The influence of all possible concomitant and combination injuries of the ankle joint, surgeon’s experience, and potential implant-related effects was analyzed. Results: Thirty-seven Weber C fractures (60.7%), 13 Maisonneuve fractures (21.3%), 10 Weber B fractures (16.4%), and 1 syndesmotic injury without fracture (1.6%) were included. In 14 cases (23%) there was involvement of the posterior malleolus, in 10 cases of the medial malleolus (16.4%), and in 12 cases both (19.7%). The Weber C fractures included 10 bimalleolar fractures with involvement of the posterior malleolus. In neither this combination nor in any other possible injury configuration was it possible to identify a statistically significant correlation with malreduction of the fibula into the fibular notch. The surgeon’s experience or an implant-related effect had no detectable influence either. Conclusion: Based on the factors studied, it is not possible to conclude whether a patient has an increased risk of malreduction. Therefore we still recommend verifying all reduction outcomes by intraoperative 3D imaging or postoperative computed tomography. Level of Evidence: Level III, retrospective comparative study.

Rare Indications for a Kausch-Whipple Procedure

OBJECTIVES To find out whether the Kausch-Whipple operation is adequate for the cure of rare tumours of the pancreatic head. DESIGN Retrospective study. SETTING University hospital, Germany. PATIENTS Of 640 patients who had Kausch-Whipple procedures between 1972 and 1998 we found 42 (6.6%) who were operated on for rare tumours of the pancreatic head. RESULTS Among these 42 patients 12 had functioning and non-functioning endocrine tumours, 11 had adenomas that were not locally resectable, 6 had leiomyosarcomas or oncocytomas, 4 had cystadenocarcinomas, 3 had acinar cell carcinomas, 2 had primary lymphomas, and 3 had metastases to the pancreatic head. Operative treatment (such as extended resection), postoperative course, and survival time after operation varied. Patients with adenomas had the most favourable mean survival time of 106.5 months. Among patients with cancer, those with endocrine malignancies had the best outcome with a mean survival duration of 58.3 months.

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.

Frakturen der Kniescheibe

ZusammenfassungIm unfallchirurgischen Krankengut treten Patellafrakturen mit einer Häufigkeit von etwa 0,5–1,5% auf. Häufige Unfallmechanismen sind Stürze auf das gebeugte Kniegelenk und Anpralltraumen bei Verkehrsunfällen. Die Diagnostik umfasst eine Röntgenaufnahme des Kniegelenks in 2 Ebenen sowie eine axiale Aufnahme der Patella. Die Patellafrakturen werden in der Praxis in Quer- und Längsfrakturen, Mehrfragment- und Trümmerfrakturen eingeteilt. Therapeutisch gelten die Grundsätze der Versorgung aller Frakturen mit Gelenkbeteiligung: möglichst stufenfreie Reposition, sichere Retention und frühzeitige funktionelle Nachbehandlung zur Vermeidung von Immobilisationsschäden. Eine konservative Therapie ist nur bei minimaler Diastase der Fragmente und fehlender Verletzung des Reservestreckapparats sinnvoll. In allen anderen Fällen besteht die Indikation zur operativen Versorgung. Obwohl experimentelle Daten das theoretische Prinzip der Zuggurtungsosteosynthese bei Patellafrakturen in Frage stellen, ist sie zurzeit als Standardverfahren der osteosynthetischen Versorgung von Quer- und Mehrfragmentfrakturen der Patella anzusehen. Darüber hinaus werden Schraubenosteosynthesen, Kirschner-Draht-Fixierungen und Kombinationen dieser Verfahren verwendet. In 1/3 der Fälle werden sehr gute Ausheilungsergebnisse erzielt. Es ist aber mit 5–36% schlechten Ergebnissen zu rechnen. Dabei stellen schmerzhafte retropatellare Arthrosen, Pseudarthrosen und Bewegungseinschränkungen im Kniegelenk die Hauptkomplikationen dar. Akzeptable Langzeitergebnisse liefert auch die primäre Patellektomie. Sie stellt somit bei ausgedehnten Trümmerfrakturen eine sinnvolle Therapieoption dar.AbstractFractures of the patella account for 0.5–1.5% of all skeletal fractures. Common mechanisms of injury are a direct fall onto the knee and dashboard injuries. Standard antero-posterior, lateral and tangential plain radiographic views confirm the diagnosis. Patellar fractures are most commonly classified according to the pattern of fracture into transverse, vertical, and comminuted fractures. The goals of operative treatment are accurate reduction, rigid fixation and the possibility of early motion of the knee. Nonoperative treatment is only justified when there is no displacement of the fragments. Tension band wiring is currently the standard operative method, although some experimental data do not support the theoretical principles behind this technique. Other operative options are screw fixation, Kirschner wires or combinations of these methods. In one-third of cases good results are achieved, while in 5–36% poor results must be expected. The most common postoperative problems are painful retropatellar arthrosis nonunion and a limited range of motion. Patellectomy is an option that yields acceptable long-term results in the treatment of comminuted fractures.

Impact of Intraoperative Cone Beam Computed Tomography on Reduction Quality and Implant Position in Treatment of Tibial Plafond Fractures.

Background: The intraoperative assessment of the articular surface in displaced intra-articular distal tibia fractures can be challenging using conventional fluoroscopy. The aim of the study was to determine the frequency and the method of intraoperative corrections of fracture reductions or implant placements during open reduction, internal fixation by using cone beam computed tomography (CT) after conventional fluoroscopy. Methods: Displaced intra-articular distal tibia fractures were retrospectively analyzed from August 2001 until December 2011. The fractures were classified according to the standards of the AO/OTA as type B or C and treated with open reduction and internal plate fixation. After primary reduction using conventional fluoroscopy, an additional cone beam CT scan was used to determine the alignment of the joint line and the implant position. The number of intraoperative revisions of the primary reduction due to the use of cone beam CT was analyzed. Results: A total of 143 patients with an intra-articular tibial plafond fracture were included in the analysis. In 43 patients (30%), an intraoperative correction was performed after the cone beam CT scan. In 34 (24%) of these cases, intraoperative correction was required because of inadequate joint line reduction. Nine (6%) corrections were required as a result of a malposition of the implant. The revision rate did not differ by fracture classification. Conclusion: Despite its acceptance as the standard method of imaging, intraoperative conventional fluoroscopy for the assessment of implant positioning and fracture reduction of tibial plafond fractures is limited. The intraoperative utilization of cone beam CT provided additional information for the surgeon to detect insufficient reduction or implant malposition. Level of Evidence: Level III, retrospective comparative series.