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Abstract Objective Thoracic outlet syndrome (TOS) is a clinical phenomenon resulting from compression of the neurovascular structures at the superior aperture of the thorax which presents with varying symptoms. Regarding to the varying symptoms, the diagnosis of TOS seems to be a challenge and predictors for the outcome are rare. The purpose of this study was therefore to analyze the different clinical examinations and tests relative to their prediction of the clinical outcome subsequent to surgery. Methods During a period of five years, 56 patients were diagnosed with TOS. Medical history, clinical tests, operative procedure and complications were recorded and analysed. Mean follow-up of the patients was 55.6 ± 45.5 months, median age of the patients was 36.4 ± 12.5 years. Results Different clinical tests for TOS showed an acceptable sensitivity overall, but a poor specificity. A positive test was not associated with a poor outcome. Analyses of the systolic blood pressure before and after exercise showed, that a distinct decrease in blood pressure of the affected side after exercises was associated with a poor outcome (p = 0.0027). Conclusions Clinical tests for TOS show a good sensitivity, but a poor specificity and cannot be used as predictors for the outcome. A distinct decrease in blood pressure of the affected side after exercises was associated with poor outcome and might be useful to predict the patients' outcome.

Abstract: The gold standard for radiographic assessment and correction planning of lower limb deformities is the long standing radiograph (LSR). Additional computer tomography (CT) can measure exact length and torsion. For correct positioning in LSR the patella should be centered on the femoral condyles (knee forward position—KFP). The flexion extension axis of the knee (KFEA) is mainly defined by the shape of the femoral condyles represented by their dorsal tangent. In 30 CT scans the position of the patella and its relation to the dorsal tangent to the femoral condyles were retrospectively analyzed. With a custom-made positioning apparatus to control the leg rotation and load exactly for each limb separately we analyzed 38 CT scans. 20 digital LRS were retrospectively compared with the correlating CT-data. In CT scans with KFP the KFEA differed 11° from the frontal plane (p <0.05). With the special positioning apparatus it was possible to control the leg rotation and align the KFEA in the frontal plane with an accuracy of 82%. There was no significant difference of axis and joint angles between the LSR and CT scanogram (p <0.05). The aberration of the KFEA in KFP has to be to taken into consideration for analysis and correction planning. The alignment of the KFEA parallel to the frontal plane can be achieved by optimized CT scans and a special positioning fixture. In certain cases the LRS can be replaced by a CT scanogram. [Copyright &y& Elsevier]

Background: Animal fracture models, primarily performed in rats, are crucial to investigate normal and pathological bone healing. However, results of biomechanical testing representing a major outcome measure show high standard deviations often precluding statistical significance. Therefore, the aim of our study was a systematical examination of biomechanical characteristics of rat femurs during three-point bending. Furthermore, we tried to reduce variation of results by individually adapting the span of bearing and loading areas to the bone's length., Methods: We examined 40 paired femurs of male Wistar-rats by DXA (BMD and BMC of the whole femur) and pQCT-scans at the levels of bearing and loading areas of the subsequent biomechanical three-point bending test. Individual adjustment of bearing and loading bars was done respecting the length of each specimen. Subgroups of light (< 400 g, n = 22) and heavy (> 400 g, n = 18) animals were formed and analysed separately. We furthermore compared the results of the individualised bending-setting to 20 femurs tested with a fix span of 15 mm., Results: Femurs showed a length range of 34 to 46 mm. The failure loads ranged from 116 to 251 N (mean 175.4 ± 45.2 N; heavy animals mean 221 ± 18.9 N; light animals mean 138.1 ± 16.4 N) and stiffness ranged from 185 N/mm to 426 N/mm (mean 315.6 ± 63 N/mm; heavy animals mean 358.1 ± 34.64 N/mm; light animals mean 280.8 ± 59.85 N/mm). The correlation of densitometric techniques and failure loads was high (DXA R 2  = 0.89 and pQCT R 2  = 0.88). In comparison to femurs tested with a fix span, individual adaptation of biomechanical testing homogenized our data significantly. Most notably, the standard deviation of failure loads (221 ± 18.95 N individualized setting vs. 205.5 ± 30.36 N fixed) and stiffness (358.1 ± 34.64 N/mm individualized setting vs. 498.5 ± 104.8 N/mm fixed) was reduced by at least one third., Conclusions: Total variation observed in any trait reflects biological and methodological variation. Precision of the method hence affects the statistical power of the study. By simply adapting the setting of the biomechanical testing, interindividual variation could be reduced, which improves the precision of the method significantly.

Objectives: Rat fracture models are extensively used to characterize normal and pathological bone healing. Despite, systematic research on inter- and intra-individual differences of common rat bones examined is surprisingly not available. Thus, we studied the biomechanical behaviour and radiological characteristics of the humerus, the tibia and the femur of the male Wistar rat-all of which are potentially available in the experimental situation-to identify useful or detrimental biomechanical properties of each bone and to facilitate sample size calculations., Methods: 40 paired femura, tibiae and humeri of male Wistar rats (10-38 weeks, weight between 240 and 720 g) were analysed by DXA, pQCT scan and three-point-bending. Bearing and loading bars of the biomechanical setup were adapted percentually to the bone's length. Subgroups of light (skeletal immature) rats under 400 g (N = 11, 22 specimens of each bone) and heavy (mature) rats over 400 g (N = 9, 18 specimens of each bone) were formed and evaluated separately., Results: Radiologically, neither significant differences between left and right bones, nor a specific side preference was evident. Mean side differences of the BMC were relatively small (1-3% measured by DXA and 2.5-5% by pQCT). Over all, bone mineral content (BMC) assessed by DXA and pQCT (TOT CNT, CORT CNT) showed high correlations between each other (BMC vs. TOT and CORT CNT: R 2  = 0.94-0.99). The load-displacement diagram showed a typical, reproducible curve for each type of bone. Tibiae were the longest bones (mean 41.8 ± 4.12 mm) followed by femurs (mean 38.9 ± 4.12 mm) and humeri (mean 29.88 ± 3.33 mm). Failure loads and stiffness ranged from 175.4 ± 45.23 N / 315.6 ± 63.00 N/mm for the femurs, 124.6 ± 41.13 N / 260.5 ± 59.97 N/mm for the humeri to 117.1 ± 33.94 N / 143.8 ± 36.99 N/mm for the tibiae. Smallest interindividual differences were observed in failure loads of the femurs (CV% 8.6) and tibiae (CV% 10.7) of heavy animals, light animals showed good consistency in failure loads of the humeri (CV% 7.7). Most consistent results of both sides (left vs. right) in failure loads were provided by the femurs of light animals (mean difference 4.0 ± 2.8%); concerning stiffness, humeri of heavy animals were most consistent (mean difference of 6.2 ± 5%). In general, the failure loads showed strong correlations to the BMC (R 2  = 0.85-0.88) whereas stiffness correlated only moderate, except for the humerus (BMC vs. stiffness: R 2  = 0.79)., Discussion: Altogether, the rat's femur of mature specimens showed the most accurate and consistent radiological and biomechanical results. In synopsis with the common experimental use enabling comparison among different studies, this bone offers ideal biomechanical conditions for three point bending experiments. This can be explained by the combination of a superior aspect ratio and a round and long, straight morphology, which satisfies the beam criteria more than other bones tested.

Knowledge of local bone quality is essential for surgeons to determine operation techniques. A device for intraoperative measurement of local bone quality has been developed by the AO-Research Foundation (Densi - Probe®). We used this device to experimentally measure peak breakaway torque of trabecular bone in the proximal femur and correlated this with local bone mineral density (BMD) and failure load. Bone mineral density of 160 cadaver femurs was measured by ex situ dualenergy X-ray absorptiometry. The failure load of all femurs was analyzed by side-impact analysis. Femur fractures were fixed and mechanical peak torque was measured with the DensiProbe® device. Correlation was calculated whereas correlation coefficient and significance was calculated by Fisher's Ztransformation. Moreover, linear regression analysis was carried out. The unpaired Student's t-test was used to assess the significance of differences. The Ward triangle region had the lowest BMD with 0.511 g/cm(2) (±0.17 g/cm(2)), followed by the upper neck region with 0.546 g/cm(2) (±0.16 g/cm(2)), trochanteric region with 0.685 g/cm(2) (±0.19 g/cm(2)) and the femoral neck with 0.813 g/cm(2) (±0.2 g/cm(2)). Peak torque of DensiProbe® in the femoral head was 3.48 Nm (±2.34 Nm). Load to failure was 4050.2 N (±1586.7 N). The highest correlation of peak torque measured by Densi Probe® and load to failure was found in the femoral neck (r=0.64, P<0.001). The overall correlation of mechanical peak torque with T-score was r=0.60 (P<0.001). A correlation was found between mechanical peak torque, load to failure of bone and BMD in vitro. Trabecular strength of bone and bone mineral density are different aspects of bone strength, but a correlation was found between them. Mechanical peak torque as measured may contribute additional information about bone strength, especially in the perioperative testing.

Background: Chronic osteomyelitis due to direct bone trauma or vascular insufficiency is a frequent problem in orthopaedic surgery. In contrast, acute haematogenous osteomyelitis represents a rare entity that almost exclusively affects prepubescent children or immunodeficient adults., Case Presentation: In this article, we report the case of acute pneumococcal osteomyelitis of the humerus in an immunocompetent and otherwise healthy 44-year-old male patient presenting with minor inflammation signs and misleading clinical features., Conclusions: The diagnosis had to be confirmed by open biopsy which allowed the initiation of a targeted therapy. A case of pneumococcal osteomyelitis of a long bone, lacking predisposing factors or trauma, is unique in adults and has not been reported previously.

Background: In this study, we evaluate a new bioadhesive for intra-abdominal onlay mesh fixation of a polypropylene-polyvinylchloride graft., Methods: Three pieces of a commercially available polypropylene/polyvinylfluoride mesh, each 3 × 3 cm in size, and three pieces of the same mesh coated with a polysaccharide bioadhesive were fixated to the surface of the anterior abdominal wall of 30 New Zealand white rabbits. The fixation was performed either by using four transabdominal Prolene(®) 4/0 sutures, four spiral tacks (Protack 5 mm Tyco), or cyanoacrylate glue (Glubran(®) GEM, Viareggio, Italy). Each mesh position and the according kind of fixation were randomized before implantation. The animals were sacrificed 12 weeks postoperatively. After determining the extent of intra-abdominal adhesions, the meshes were excised en bloc with the anterior abdominal wall for tensile strength measurements and histological analysis., Results: All meshes coated with the bioadhesive adhered to the intact peritoneum without extra fixation. Irrespective of the fixation technique coated meshes led to more and stronger adhesions. Mesh shrinkage by scarring was increased in coated meshes fixed with glue and low in uncoated meshes fixed with tacks. Testing the tensile strength, coated meshes fixed with transfascial sutures achieved the best results (16.14 ± 6.1 N), whereas coated meshes fixed with glue showed the lowest strength (10.39 ± 4.81 N). The foreign body reaction was considerably more distinctive using coated mesh. The mesh ingrowth was not influenced by this reaction., Conclusions: All meshes coated with the new bioadhesive were self-adhesive in that way; they stayed in position when attached to the peritoneum. Although this may facilitate intra-operative mesh fixation, the bioadhesive displayed several disadvantages, such as stronger adhesions and an increased shrinkage of the implant. The tensile strength was not influenced by the use of the bioadhesive. At present, we see no major advantage for polysaccharide bioadhesive applied in this study.

Objectives: A profound knowledge of physiologic lower limb alignment is essential to understand deformities and to plan surgical correction. The gold standard in radiographic assessment is the long standing radiograph with a forward directed patella. The advantage of computed tomography (CT) is that its cutting-edge image technique can visualize the femur condyles. Study purpose was to determine if the CT-scout view has the potential to replace the standing radiograph., Materials and Methods: We compared the geometric data obtained from long standing radiograph and CT-scout views both with patella forward position. Furthermore, we developed a method of positioning the lower extremity stable on the CT table, where the femoral condyles became the new orientation criterion. Finally, we evaluated differences in the data ascertainment between the long standing radiograph with patella facing forward and the CT-scout view with the posterior edge of femoral condyles orientated parallel to the radiographic cassette., Results: The geometric data of long standing radiograph and CT-scout views are comparable if the leg is in the same rotational position. We developed a CT positioning jig to adjust the femur condyles parallel to the radiographic cassette. In 80 % of the cases, the deviation was 5° or less. These scout views showed statistically significant differences when compared with data from standing radiograph with a forward centered patella., Conclusion: No evidence was found clearly excluding the possibility of an exclusive use of the CT-scout view for the analysis of the leg geometry. However, advantages of the long standing radiograph became obvious.

Total hip arthroplasty is the procedure of choice for most patients with advanced, symptomatic osteoarthritis due to congenital dysplasia of the hip. However, the complexity of arthroplasty is significantly increased because of anatomic abnormalities associated with dysplasia of the hip. In addition the relatively young age of patients may affect survival of the implant. From a biomechanical standpoint the primary surgical objective is reconstruction of the anatomical center of rotation. Independent of the pelvic bone stock the socket should be located as near as possible to the anatomical acetabular location. There are various operative strategies to ascertain sufficient stability of the socket. The anterolateral deficiency of the acetabulum can be reconstructed by bulk femoral autografting or bone impaction grafting. Furthermore controlled perforation of the medial wall or implantation of reinforcement rings and oval sockets have been described. Cementless, biological socket fixation shows superior long-term results compared to cemented cups, especially in these young patients. The location of the reconstructed acetabulum and the desired leg length influence the type of femoral reconstruction and in some cases femoral shortening is required. In this article endoprosthetic reconstructive options for developmental dysplasia of the hip are discussed depending on the femoral and acetabular deformity.

Background: Cyanoacrylate glues are tissue adhesive with high adherent and hemostatic properties. The aim of this study was to evaluate the efficacy of cyanoacrylates glue for polypropylene-polyvinylidene fluoride (PP-PVDF) intraperitoneal onlay mesh (IPOM) fixation in a rabbit model., Materials and Methods: In 40 New Zealand white rabbits, three pieces (3×3cm) of a PP-PVDF mesh (n=120) were fixed in IPOM technique on both sides of a midline laparotomy. For mesh fixation we used spiral tacks, nonabsorbable sutures, or cyanoacrylate glue in a randomized manner. All animals were killed after 12 wk. The prosthetic materials were excised en bloc with the anterior abdominal wall for evaluation of the tensile strength and histologic analysis. Results are presented as mean and standard deviation., Results: Meshes fixed with glue showed a significantly higher tenacity of adhesions (2.75±0.97) compared with those with tacks (2.44±0.97 sutures versus 1.91±0.92 tacks). The percentage of adhesions in the glue group was comparable to the suture group (36.50% ± 27.60% glue, 37.62% ± 27.36% suture). The tensile strength of stapled and sutured meshes was significantly higher than the tensile strength glued mesh (14.15±0.97N suture versus 14.84±0.74 stapler versus 9.64±0.78N glue). Mesh shrinkage was irrespective of the fixation technique. The inflammation reaction was more pronounced in the glue group., Conclusions: Although cyanoacrylate glue showed a considerable cellular ingrowth in this rabbit model, sutures and tacks proved to be superior for IPOM fixation of PP-PVDF meshes in terms of tensile strength., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Diabetic neuropathic osteo-arthropathy (DNOAP; Charcot arthropathy) is a progressive disease characterized by joint luxation, fractures and excessive destruction of foot architecture. The operative therapy is indicated when conservative therapy fails, in progressive breakdown, in hindfoot Charcot and in spreading infections due to plantar ulcers. The complication rate of 10-20% in open surgery is high. We present a minimally invasive technique of closed reduction and application of a ring fixator for reconstruction of the foot architecture and arthrodesis of the involved joints.

Introduction: In trauma patients, injury of solid abdominal organs secondary to blunt trauma is a major source of morbidity and mortality. Different diagnostic options such as FAST sonography or CT scan have been described., Methods: Our trauma registry was used to identify multiple injured patients with blunt abdominal trauma during 2001 to 2006. Patient demographics, diagnostic and operative findings, treatment, complications, length of stay and mortality were reviewed., Results: Of 438 multiple injured patients, 58 patients were diagnosed with blunt abdominal trauma. During examination, free fluid or organ injury could be seen in 72.4% during sonography and in 84.3% of the patients who received CT scan, giving a sensitivity of 92% for initial FAST Sonography. Nevertheless, CT scan showed a higher sensitivity in detecting bowel (84%) or mesenteric (75%) injuries, if compared to FAST. 30 (51.7%) of the 58 patients had to undergo laparotomy because of blunt abdominal trauma, giving a laparotomy rate of 6.8% because of blunt abdominal trauma in multiple injured patients., Conclusion: Sonography is the method of choice for initial screening and CT scan in detecting bowel or mesenteric injuries. A large intraperitoneal fluid accumulation during initial sonography in combination with unstable vital signs should lead to an immediate exploratory laparotomy.

The implementation of clinical pathways has a proven positive effect on the diagnostic workup and initiation of therapy in osteoporotic fracture patients. Unlike in most countries, fracture care in Germany is provided by so-called trauma surgeons. Therefore, it is essential to focus on the trauma surgeon for correct diagnostic workup and therapy initiation after a fragility fracture. A questionnaire was mailed to 409 departments of traumatology inquiring about the existence of a standardized clinical pathway for diagnosis and treatment of patients with fragility fractures. One of the central issues of the survey was whether those pathways comply with national guidelines. Only institutions that stated that they followed a clinical pathway were analyzed. 80% of institutions took part in our survey, 35% of which reported following a defined clinical pathway. Diagnostic workup is in concordance with the national guidelines in 30%, and therapy is guideline-based in 51%, with 12% basing both diagnostic workup and therapy on the guidelines. Thus, the vast majority of German traumatology departments do not follow national guidelines regarding osteoporosis diagnostics and therapy in patients with fragility fractures, leading to a great opportunity to improve fragility fracture care by means of both education and interdisciplinary cooperation.

Clavicle fractures are common, with the majority treated conservatively. If treated conservatively, pseudarthrosis of the clavicle is reported in up to 3% of the cases. In rare cases, pseudarthrosis of the clavicle may cause pseudoaneurysm formation, resulting in compression of the brachial plexus and the adjoining vessels, which may produce neurological symptoms and circulatory disorders. Here, we describe two cases of the late onset of pseudoaneurysm formation after pseudarthrosis of the clavicle. Both cases were remarkable because they showed clinical symptoms of TOS. Therefore, surgical treatment was performed and included claviculectomy, resection of the pseudoaneurysm and interposition grafting with an artificial prosthesis. One year after the operation, both patients showed excellent upper extremity function without any deficit of vascular, sensorial or motorial function. Patient's history and radiological findings are the keys to diagnosis. Without treatment, the prognosis is poor with spontaneous development of bleeding or gangrene. Therefore, surgical treatment has to be performed, especially when neurological symptoms occur.

Objective: Skin and soft tissue abscesses are common findings in injecting drug users (IDUs) who present to the surgical emergency department for evaluation and treatment. Although most cases can be managed by incision and drainage, they do require special considerations as compared to abscesses which are not caused by intravenous drug abuse., Methods: Skin and soft tissue abscesses treated in the emergency department between 2005 and 2007 were reviewed and a systematic literature search of skin and soft tissue abscesses in IDUs was conducted, including the etiology, occurrence, risk factors, and treatment options, thus providing the rationale for the treatment algorithm presented herein., Results: The drugs injected, the technique by which they were injected, the attendant circumstances, as well as the immunological status of the IDUs were major factors for the development of abscesses. Skin and soft tissue abscesses in IDUs should be incised and drained under local or general anesthesia depending on the size, location, and association with neurovascular structures. Different factors have been taken into account when treating soft tissue abscesses in this population which predict their specific risks and therefore further therapy needs. The incidence of tetanus is high among IDUs compared to the general population, giving rise to the recommendation for a strict booster policy if the vaccination status is unclear when the patient presents to the emergency department. The presence of fever requires hospitalisation and evaluation for the presence of endocarditis. Foreign bodies, such as broken needles, should be ruled out by radiography, and duplex sonography should be performed to identify the presence of vascular complications. Prior to incision and drainage, prophylactic antimicrobial agents should be administered to every patient and as therapy for high-risk patients, such as immunocompromised patients and patients with fevers and chills., Conclusions: IDUs presenting with skin and soft tissue abscesses can be managed safely if some special issues are taken in account. The presented algorithm may help facilitate the decision-making in this context.

Objective: The aim of this study was to evaluate the technique of prosthetic mesh fixation in laparoscopic intraperitoneal incisional and ventral hernia repair using cyanoacrylat glue (Glubran GEM, Viareggio, Italy) in comparison with fixation methods using spiral tacks (Protack 5mm, Tyco) or transabdominal Prolene 4/0 sutures respectively., Method: Through a midline laparotomy 3 pieces (3 x 3cm) of mesh (n = 60) where fixed onto the intact peritoneum on either side of a midline laparotomy in 10 New Zealand White rabbits. Two types of meshes where compared: ePTFE meshes (Gore-Tex Dual Mesh W.L. Gore and Associates, Inc. Medical Products Division, Flagstaff, Arizona, USA) and polypropylene/ polyvinylfluorid meshes (Dyna Mesh - IPOM P.J. Dahlhausen and Co. GmbH, Germany). All animals were killed after 12 weeks. Upon scoring of the adhesions the prosthetic materials were excised en bloc with the anterior abdominal wall for tensile strength analysis and histologic evaluation., Results: In contrast to ePTFE meshes fixed with cyanoacrylat glue, PP meshes fixed with transabdominal sutures as well as with spiral tacks showed the highest percentage and tenacity of adhesions (p<0.033). Independent of the method of fixation, ePTFE meshes revealed a significantly higher shrinkage than PP prosthesis (41% vs 17% related to original mesh surface; p<0.033). The strength of the mesh incorporation was significantly higher in PP meshes (p<0.033). Fixation of PP meshes with cyanoacrylat glue showed an equivalent tensile strength as ePTFE meshes fixed with spiral tacks (6.6 +/- 2.7 N vs 6.6 +/- 3.1N)., Conclusion: In this rabbit model, intraabdominal fixation of PP composite meshes with cyanoacrylat glue was equivalent to ePTFE mesh fixation with spiral tacks concerning tensile strength analysis. Adhesions between mesh and abdominal wall were found more frequently after PP fixation. In contrast, mesh shrinkage was more evident after ePTFE mesh implantation.

In German-speaking countries, most serious thoracic injuries are attributable to the impact of blunt force; they are the second most frequent result of injury after head injury in polytrauma patients with multiple injuries. Almost one in every three polytraumatized patients with significant chest injury develops acute lung failure, and one in every four, acute circulatory failure. The acute circulatory arrest following serious chest injury involves a high mortality rate, and in most cases it reflects a tension pneumothorax, cardiac tamponade, or hemorrhagic shock resulting from injury to the heart or one of the large vessels close to it. Brisk drainage of tension pneumothorax and adequate volume restoration are therefore particularly important in resuscitation of multiply traumatized patients, as are rapid resuscitative thoracotomy to allow direct heart massage, drainage of pericardial tamponade, and control of hemorrhage. However the probability of survival described in the literature is very low for patients sustaining severe chest trauma with acute cardiac arrest. The case report presented here describes a female polytrauma patient who suffered an acute cardiac arrest following cardiac tamponade after admission in the emergency department and who survived without neurological deficits after an emergency thoracotomy. Selections from the topical literature can help the treating physician in the emergency department in making decisions on whether an emergency thoracotomy is indicated after a blunt chest injury and on the procedure itself.

Purpose: To present the concept of double tube stent-grafts and examine the indications for and results achieved with these devices., Methods: From January 1, 2000, to December 31, 2005, 759 patients who underwent endovascular repair of infrarenal aortic aneurysms at 2 centers. Of these, 45 (5.9%) patients received a double tube stent-graft; complete operative and follow-up data were available for retrospective analysis in 41 patients (33 men; mean age 73.1+/-8.9 years). Diameters measured before stent-graft implantation and at follow-up (12, 24, 36, and 48 months) with clinical examination, 2-phase computed tomographic angiography, duplex sonography, and biplanar abdominal radiography were tested for significant changes using ANOVA with the Bonferroni-Dunn correction. Late outcomes (clinical success and endoleak) were analyzed by the Kaplan-Meier method., Results: The postoperative complication rate was 12.2%, with 2.4% systemic complications (1 patient with angina pectoris); the early mortality rate was 0%. Mean follow-up was 21.9+/-12.8 months (range 12-61) for the 41 patients. Four (9.8%) patients died during follow-up of cardiac causes (n = 2), lung cancer (n = 1), and bowel ischemia (n = 1). Four (9.8%) endoleaks were observed during follow-up: 1 distal type I, 2 type II, and 1 type III. Maximum aneurysm diameters shrank from 52.0+/-9.5 mm preoperatively to 44.0+/-10.9 mm (p<0.0001) postoperatively at the latest available follow-up., Conclusion: Our study supports the use of this double tube technique for repair of appropriate saccular infrarenal aortic aneurysms. The double tube stent-graft method appears safe in terms of endoleaks and migration, so we recommend that it be considered an option of endovascular aortic aneurysm therapy.

Recently, it has been shown that quantitative scanning acoustic microscopy (SAM) is a powerful tool to image the acoustic impedance of even inhomogeneous materials like bone. Therefore, the aim of our study was to compare SAM to conventional microradiography with respect to histomorphometrical assessment of undecalcified sections of newly formed bone. Forty specimens were harvested 12 weeks after implantation of either autogenous cancellous bone graft or 5.0 mg of Osteogenic Protein-1 (BMP-7) in a critical-sized defect model in sheep. Undecalcified transverse bone sections of 500 microm thickness were investigated with conventional microradiography and SAM. Linear regression analysis was carried out to compare the measurements of the area of new bone formation within the defect sites. Both methods allowed for good discrimination between newly formed bone and cortical bone at the edges of the former defect. Images obtained with SAM revealed a better resolution and sharpness compared to that of microradiographs since SAM imaging unlike microradiography does not depend on the thickness of bone sections. The results of quantitative histomorphometric analysis obtained by both methods showed no significant differences, and it was possible to predict 90% of the variability of each method (coefficient of determination r2 = 0.90; P < 0.0001). In conclusion, SAM offers comparable quantitative histomorphometric information with a better spatial resolution than conventional microradiography. Thus, SAM is a promising new micro-visualizing technique for basic bone research.