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U Stöckle

Publications and source records attributed to U Stöckle.

At least 19 recordsLinked to original sources
PubMed2006

[Clinical experience with the Siremobil Iso-C(3D) imaging system in pelvic surgery].

In pelvic and acetabular surgery intraoperative control of reduction and implant position is sometimes hard to achieve with conventional C-arm technology. The Siemens C-arm Iso-C(3D) imaging system enables axial cuts and two- or three-dimensional reconstructions to be generated. Following the good experience in surgery of the spine and extremities, its clinical applicability in pelvic surgery was evaluated in 30 patients in a prospective clinical trial. In all 20 patients with acetabular fractures reduction quality and implant position could be well assessed. In one postoperative examination an intraarticular screw placement was evident, which intraoperatively was not as clear and was revised. In one procedure an intraarticular fragment was visualized, and was extracted in the same procedure. In one procedure the use of the Iso-C(3D) system enabled the approach to be limited. In all ten pelvic ring injuries the osseous structures in the posterior pelvic ring could be visualized with an adequate image quality. Reduction quality and implant position could be assessed in all open and closed procedures. On two occasions the SI screws were navigated based upon the Iso-C(3D) dataset. Overall the use of the Iso-C(3D) system was successful in all cases. Image quality, which is clearly inferior to that of CT, was sufficient for the assessment of reduction quality and implant position. One revision was indicated, and one avoided. However, in spite of its advantages in pelvic surgery, handling, sterile covering and data transfer need to be improved. For bilateral pelvic injuries the image size is too small.

Acetabulum↗
PubMed2006

[Traumatic aneurysm of the superior mesenteric artery associated with a burst- fracture of the second lumbar spine -- unforeseen sequelae of a fall from a ladder!].

Traumatic aneurysms of the superior mesenteric artery, although uncommon, are nevertheless life-threatening because of their high risk of rupture. In this case report the aneurysm was accompanied by a burst fracture of the second lumbar spine nearly at the same height. In a prolonged case the diagnosis of the injury was delayed. The clinical manifestation of repeated episodes of abdominal pain did not recur after resection of the aneurysm and interposition of a venous autograft.

Abdomen, Acute↗
PubMed2006

[Percutaneous reduction and stabilization of a dislocated acetabular fracture. Case report].

In the treatment of acetabular fractures, anatomic reconstruction of the joint is the primary aim. To achieve this, rather large approaches with approach-related morbidity are needed. Percutaneous stabilizations are still limited to nondisplaced or minimally displaced fractures. For displaced acetabular fractures there are percutaneous procedures described with intraoperative CT control, requiring that CT be available in the OR and posing a logistic challenge. The fluoroscope Siremobil Iso-C3D offers the possibility of displaying osseous structures with CT-like quality using a fluoroscopy technique. The case of a minimally displaced acetabular T-type fracture with a clear articular step in the weight-bearing area is presented. The percutaneous reduction and stabilization after intraoperative control of the reduction quality with the Siremobil Iso-C3D is demonstrated. Using the enhanced fluoroscopy technology with the ability to generate axial cuts and reconstructions comparable to CT clearly improves the reduction control also in acetabular surgery. Thus even displaced acetabular fractures can be reduced and stabilized percutaneously. Anatomic reconstruction of the joint remains the primary aim.

Acetabulum↗
PubMed2006

[Integrated navigation. Preclinical evaluation and initial clinical experience].

BACKGROUND: Computer navigation systems have increasingly become part of the surgical routine due to the improvements of intraoperative visualization procedures. Because of limited space in the operating room and insufficient workflow, the project of integrated navigation had been started. METHODS: As the first step, the navigation system VectorVision2 and the second-generation fluoroscopic C-arm system Orbic 3D were integrated into one common trolley. In an experimental study the integrated navigation system was used to drill 160 pedicle screws. Afterwards the system was clinically evaluated in 11 surgical procedures. RESULTS: During the whole experimental study the system could be used for all 160 drilling procedures without any technical faults, causing a failure rate of 4.2%. For clinical evaluation the integrated navigation system was used in seven patients with navigated dorsal spine instrumentation, in three cases sacroiliac screws were placed, and in one case supra-acetabular screw osteosynthesis was performed for an acetabular fracture. In all cases the positioning of the screws was correct and no system failure occurred. CONCLUSIONS: The combination of the navigation system and the C-arm system in one common trolley is a major improvement of the surgical workflow. In the experimental study and the clinical trials the system worked extremely reliably and with high precision.

Acetabulum↗
PubMed2005

Stabilisation of periprosthetic fractures with angular stable internal fixation: a report of 13 cases.

INTRODUCTION: Periprosthetic fractures of the femur present a challenging surgical problem. The aim of this study was to retrospectively evaluate the outcome of periprosthetic fractures stabilised with an angular stable, less invasive stabilisation system (LISS). PATIENTS AND METHODS: Thirteen patients (ten total hip-, two total knee-, one total hip- and knee-arthroplasty) with periprosthetic fractures were treated with the LISS internal fixator (in ten cases minimal invasive). Six patients had previous operations due to periprosthetic fractures. The average follow-up period was 20 months, follow-up rate 85%. RESULTS: All fractures showed radiographic fracture healing without implant loosening. Except one patient, all patients had returned to their pre-operative activity level. No early post-operative complications were seen. There was one implant failure after 4 months and two cases of malunion. CONCLUSION: The cases showed the internal fixator to be effective for the stabilisation of periprosthetic fractures, even in cases of poor bone quality with good functional outcomes. The internal fixator, with the option of minimal invasive application, is the preferred method of osteosynthesis in periprosthetic fractures.

Accidental Falls↗
PubMed2005

[Evaluation of image quality of the Iso C3D image processor in comparison to computer tomography. Use in the pelvic area].

Intraoperative 3-D visualization using the Siremobil Iso C(3D) (Siemens, Erlangen, Germany) has been approved for use in spine and long bone surgery since its recent clinical launch. In preparation for the clinical use of the Siremobil Iso C(3D) in pelvic surgery, the aim of this study was to grade the quality of visualization in comparison with the gold standard of computer tomography in four therapy relevant pelvic regions in eight human cadavers, including SI screws to exemplify implants in the dorsal pelvic ring. Besides the influence of the body mass index and the interference of metal artefacts, visualization quality was evaluated in different pelvic regions (sacroiliac joint, acetabulum, femoral neck and anterior pelvic ring) using a score with five subgroups, rating the applicability of Siremobil Iso C(3D) in pelvic surgery. The grading of image quality in comparable standard projections was performed independently by three surgeons and three radiologists.Visualization quality appeared sufficient for both intraoperative and postoperative control in cases with a known preoperative diagnosis. There was no influence of body mass index found in any of the eight cadavers. Implants positioned in the dorsal pelvic ring reduced visualization quality, but sufficient estimation of bony structures was still possible. For primary diagnostics, computer tomography remains a clearly superior option due to better image quality. For intraoperative control of the reduction and positioning of implants in pelvic surgery, however, the additional intraoperative use of Siremobil Iso C(3D) is considered to offer clear advantages over current 2-D C-arm visualization tools.

Cadaver↗
PubMed2005

[Periprosthetic fractures after total knee joint arthroplasty].

Periprosthetic fractures of the femur, tibia and patella are being registered with increasing frequency due to the rising numbers of total knee replacements. Depending on the site of the fracture, apart from mere traumatic mechanisms, implant specific parameters and implant loosening may represent the main causes of periprosthetic fracture. Moreover, general risk factors promote the manifestation of a periprosthetic fracture. Nowadays, valid classifications are available to categorize periprosthetic fractures of the femur, tibia and patella, and to create the basis for specific decision-making in choice of treatment. Despite a wide field of treatment options, the actual functional outcome after therapy and the high rates of complications imply that an adequate analysis of the fracture etiology and the corresponding transfer into an individualized treatment concept offer the chance of functional restoration of the patient similar to the pre-fracture state.

Arthroplasty, Replacement, Knee↗
PubMed2005

[Comparison of radiation dose and image quality of Siremobil-IsoC(3D) with a 16-slice spiral CT for diagnosis and intervention in the human pelvic bone].

PURPOSE: To compare the image quality of 16-slice computed tomography with the image quality of Siremobil-IsoC (3D) of the pelvic region and to measure simultaneously the radiation dose before and after implantation of a sacroiliac screw (SI-screw) MATERIALS AND METHODS: The pelvic region of 8 human cadavers was examined in the Siremobil-IsoC (3D) at five different levels. We used a standard protocol for the 16-slice CT of the complete pelvic region before and after insertion of a pelvic screw, followed by stepwise reduction of the tube current to find the tube current that equalizes the image quality of both modalities. We controlled the image quality by judging important structures such as neuroforamen, nerves, sacroiliacal joint space, intervertebral space, osteophytes, iliopsoas muscle, acetabular surface, fovea centralis, hip joint and os pubis. The image quality was judged by three radiologists and three trauma surgeons using a ranking from 1 to 5. The dose was measured with an endorectally placed NOMEX Dosimeter, to obtain the gonadal dose. RESULTS: The medium score for all viewers of the Siremobil-IsoC (3D) examinations was between 3 and 4.3. The medium score for all CT-examinations with a tube current of 250 mA was between 1.3 and 2.2. The reduction of tube current down to 80 mA hardly influenced the marks for the analyzed structures. Under 80 mA, bony structures, even after implantation of a SI-screw, were still marked as good, but soft tissue differentiation was getting worse. For the examination of the pelvis, the average dose-length product for the IsoC (3D) was 41.2 mGy x cm. The medium dose-length product for CT was 389 mGy x cm for 250 mA, 125 mGy x cm for 80 mA and 82 mGy x cm for 60 mA. CONCLUSION: The Siremobil-IsoC (3D) is sufficient for therapeutic intraoperative purpose, but the image quality is not sufficient for diagnostic purpose. The higher dose-length product of a CT examination is justifiable because of a better overview, shorter examination time and qualitative superiority. An advantage of the Siremobil-IsoC (3D) is the intraoperative availability with acceptable 3D image quality compared to conventional fluoroscopy.

Bone Screws↗
PubMed2004

[Accuracy of CT-based navitation of pedicle screws in the thoracic spine compared with conventional technique].

The goal of this study was to evaluate the accuracy of CT-based computer-assisted pedicle screw insertion in the thoracic spine in patients with fractures, metastases, and spondylodiscitis compared to a conventional technique. A total of 324 pedicle screws were inserted in the thoracic spines of 85 patients: 211 screws were placed using a CT-based optoelectronic navigation system assisted by an image intensifier and 113 screws were placed with a conventional technique. Screw positions were evaluated with postoperative CT scans by an independent radiologist. In the computer-assisted group, 174 (82.5%) screws were found completely within their pedicles compared with 77 (68.1%) correctly placed screws in the conventional group ( p<0.003). Despite use of the navigation system, 1.9% of the computer-assisted screws perforated the pedicle wall by more than 4 mm. The additional use of the image intensifier helped to identify the correct vertebral body and avoided cranial or caudal pedicle wall perforations.

Adolescent↗
PubMed2004

[Interdisciplinarity in reconstructive surgery of the extremities].

From the perspective of trauma and orthopedic surgery interdisciplinary reconstructive surgery of the extremities encompasses different indications ranging from IIIB/Copen fractures with major segmental loss of bone and soft tissue, to arterial vessel in-jury necessitating vascular repair and to biological, plastic reconstructions following resections of musculoskeletal tumors. The interdisciplinary treatment concept including trauma-orthopedic surgery combined with vascular, plastic and neuro- as well as microsurgery has significantly decreased amputation rates and functional deficits thereby improving quality of life and long-term oncological outcome The multisdisciplinary management of both complex trauma and malignant bone/ soft tissue sarcoma of the extremity is an integral task of the surgical trauma or tumor center. Close interdisciplinary communication and expierence are the precondition for performance of a priority-adapted therapeutic strategy, low complication rates and improvement of overall prognosis.

Extremities↗
PubMed2004

[Shock trauma room diagnosis: initial diagnosis after blunt abdominal trauma. A review of the literature].

OBJECTIVE: Blunt abdominal trauma is most common in the polytraumatized patient and beside neurocranial trauma one major determinant of early death in these patients. Therefore, immediate recognition of an abdominal injury is of life-saving importance. METHODS: Clinical trials were systematically collected (Medline, Cochrane and hand searches) and classified into evidence levels (1 to 5 according to the Oxford system). RESULTS: Clinical examination is not reliable for evaluation of abdominal injury. Abdominal ultrasound, especially if only focusing on free fluid (FAST) is not sensitive enough. Today, CT-scan of the abdomen is the gold-standard in diagnosing abdominal injury. Diagnostic Peritoneal Lavage (DPL) has a high sensitivity but in our region only is used in exceptional cases. The patient with continuing hemodynamical instability after abdominal trauma and evidence of free intraperitonial fluid has to undergo laparotomy. CONCLUSION: After blunt abdominal trauma, initially ultrasound investigation should be performed in the emergency room. This should not only focus on free intraabdominal fluid but also on organ lesions. Regardless of the findings from ultrasound or clinical examination, the hemodynamically stable patient should undergo a CT-scan of the abdomen in order to proof or exclude an abdominal injury.

Abdominal Injuries↗
PubMed2003

[CT and fluoroscopy based navigation in pelvic surgery].

Navigation procedures based upon CT data were introduced into spine surgery in 1994. Since then the method has been used in other areas, such as joint replacement, reconstructive surgery and tumor surgery, because of its high precision and reduced radiation exposure. The original CT-based spine module can be adapted for pelvic surgery with the prerequisite, that the positioning of the fragments is identical in CT and at operation; otherwise, a new data set has to be acquired. The experience with CT-based navigation in pelvic surgery will be explained in the context of five percutaneous screw fixations and three tumor resections. The technique will be described. The fluoroscopy-based navigation has been used in trauma surgery since the late 1990 s. Since than the method has gained wide acceptance in the field of joint replacement and reconstructive surgery as well. Between June 2000 and December 2002 we performed 36 percutaneous screw fixations in the pelvis with postoperative X-ray and CT control. Thirty five of the 36 screws were placed correctly. In one screw an anterior cortex perforation of the sacrum was seen on CT, but without neurological consequences. Based upon our clinical experience we believe that CT-based navigation is indicated in screw fixations for minimally displaced pelvic injuries or dysplasia and, with increasing importance, in tumor surgery. Fluoroscopy based navigation with adequate image quality is the method of choice for SI screw fixations in traumatic or degenerative instabilities, especially if an update of the images is needed.

Bone Neoplasms↗
PubMed2002

[Computer assisted pelvic and acetabular surgery. Clinical experiences and indications].

CT based navigation has been used in spine surgery since 1994. Several clinical studies could show an increase in precision compared to the conventional technique and thus nowadays the navigated pedicle screw placement is a routine procedure in many hospitals. Based upon the experience in spine surgery the CT based navigation module was used for percutaneous screw fixations in minimally displaced pelvic ring and acetabular fractures. After preclinical experimental trials the C-arm navigation was used for 19 screw fixations. The postoperative control of the screw position was performed with postop. X-ray and CT. Overall 23 of the 24 screws were placed correctly. In one SI screw the postoperative CT could reveal a ventral cortex perforation of the sacrum without any clinical symptoms. Based upon this limited clinical experience we see the indication for CT based navigation in minimally displaced acetabular fractures or in SI screw fixations in case of sacral dysplasia. The C-arm based navigation with adequate image quality is our method of choice for SI screw fixation in traumatic or degenerative instabilities, especially if reduction maneuvers are necessary.

Acetabulum↗
PubMed2002

Treatment of complex acetabular fractures through a modified extended iliofemoral approach.

OBJECTIVES: To assess the rate of anatomic reconstructions as well as approach-related morbidity and complications in the treatment of complex acetabular fractures through a modified extended iliofemoral approach. DESIGN: Prospective clinical study. SETTING: Level I trauma center, University Hospital. PATIENTS: Inclusion criteria were as follows: (a) associated acetabular fracture or transverse fracture with comminuted roof area stated as not sufficiently reconstructable through a single approach, and (b) age between sixteen and sixty-five years. A total of forty-nine patients with fifty complex acetabular fractures could be included out of the series of ninety-six acetabular fractures treated operatively from August 1992 to February 1996. Open reduction and internal fixation of complex acetabular fractures through the modified extended iliofemoral approach were performed. RESULTS: In 80 percent of the fifty fractures the reduction was anatomic with a remaining displacement of less than or equal to one millimeter, in eight cases there was a persistent displacement of two millimeters, and two fractures had a poor result with a three-millimeter displacement. Complications included 8 percent loss of reduction, 13 percent heterotopic ossification grade 3, and 4 percent avascular femoral head necrosis. At the two-year follow-up there were 74 percent good or excellent radiographic and clinical results. Two patients had already been reoperated with total hip replacement, and the two patients with femoral head necrosis are currently scheduled for arthroplasty. CONCLUSIONS: The modified extended iliofemoral approach proved to be appropriate to achieve anatomic reduction in complex acetabular fractures. The high rate of approach-related morbidity has to be considered carefully and may lead to a decreased incidence of extended approaches.

Acetabulum↗
PubMed2001

[Navigation assisted by image conversion. An experimental study on pelvic screw fixation].

Within an experimental trial the new method of fluoroscopy based navigation was tested for percutaneous pelvic screw fixations. A regular C-arm was used and the navigation system developed by Medivision. In a first step appropriate C-arm projections were defined for five standardized screw positions. Then precision and fluoroscopy time of 60 screws in 6 artificial pelves were evaluated. For the sacroliacal screw in S1, S1 screw in S2, anterior column screw, posterior column screw and the supraacetabular ilium screw three to four appropriate projections were defined. These were all combinations of the known special pelvic views inlet/outlet and iliac/obturator. Using these standardized views the average fluoroscopy time was 6 seconds per screw. 51 screws (85%) were inserted correctly. In five cases there was a slight deviation without perforating the cortex, four times the cortex was perforated.

Acetabulum↗
PubMed2000

[Operative treatment of complex acetabular fractures through the modified extensile iliofemoral approach].

Fourty-nine patients with 50 complex acetabular fractures were treated with open reduction and internal fixation from August 1993 to February 1996 in a prospectively documented study. The fractures were fixed with small fragment implants through a modified extensile iliofemoral approach (Maryland approach). Thirty-seven patients were polytraumatized with an ISS of 20 pts. on average. In 10 patients the ISS was > 25 pts. Good or anatomic initial fracture reduction with a fragment stepoff K 2 mm could be achieved in 48 fracturers (96 %). Thirty-six patients with 37 fractures could be evaluated after 25 months on average. In 28 fractures (76 %) the functional outcome was good or excellent according to the d'Aubigne and Harris scores. Radiological results were excellent in 21 fractures (57 %) and satisfactory in 12 fractures (Heeg score). In 7 cases (14 %) a postoperative subcutaneous seroma had to be treated surgically. No wound infections, however, were observed. Further complications were secondary a loss of reduction in 4 cases (11 %), relevant heterotopic ossifications (Brooker III/IV) in 5 cases (14 %), and aseptic femoral head necrosis in 2 cases (5 %). In two cases a total hip replacement (THR) for posttraumatic arthritis had to be performed. Two more cases are scheduled for THR due to symptomatic femoral head necrosis. A good joint reconstruction can be achieved through the modified extensile iliofemoral approach (Maryland) in complex fractures of the acetabulum. However, the approach related morbidity seems to be worrisome. In complex fractures with comminution in the roof of the acetabulum the prognosis remains uncertain even in cases where initial anatomic joint reconstruction can be achieved.

Acetabulum↗
PubMed2000

[Cast immobilization versus vacuum stabilizing system. Early functional results after osteosynthesis of ankle joint fractures].

In a prospective randomized trial the early functional results after immobilisation in a cast were compared to those after using a vacuum stabilizing system. The vacuum stabilizing system Vacoped offers equivalent stability compared to a plaster cast. In contrast to the cast the Vacoped can be removed for body care and physical therapy. Additionally the range of motion for dorsal flexion/extention in the upper ankle joint can be adjusted. From 9/1996 to 7/1997 there were 40 patients included in the study with an operated ankle fracture as monotrauma. Six weeks postoperatively the patients with cast treatment showed significantly higher functional deficits for the upper ankle joint (20%), the lower ankle joint (40%) and muscle atrophy (2.1 cm side difference) than the group with the vacuum stabilizing system (upper ankle joint 15%, lower ankle joint 25%, 1.4 cm muscle atrophy). Five patients out of the group with the vacuum system were already at work three weeks postoperatively. Three months postoperatively the functional results for both groups were approximating. The vacuum stabilizing system Vacoped offers better early functional results than conventional cast treatment after osteosynthesis of ankle fractures. Because of the increased patient comfort and the early ability for physical therapy the vacuum stabilizing system is preferable to cast treatment.

Adult↗