Study DesignBiomechanical Basic Research.ObjectivesType II Fractures of the dens axis (DFTII) are common fractures of the cervical spine in geriatric patients. A surgical approach is the anterior screw fixation (ASF). However, a disadvantage is the high post-operative rate of non-union. This study aimed to develop and biomechanically test an osteosynthesis plate (OSP) for the anterior treatment of DFTII in comparison to ASF.MethodsA novel OSP was developed and manufactured. The OSP was biomechanically tested in comparison to ASF in synthetic bone models and geriatric human cadaveric bone. An analysis of the bone microstructure of the human C2 vertebrae was performed utilizing high-resolution quantitative computed tomography to exclude differences in bone quality among the experimental groups. Biomechanical testing was performed by cyclic loading of compression and tensile forces until failure.ResultsIn the comparative biomechanical analysis of ASF and OSP in synthetic bone, significant differences were observed regarding the load to failure, favoring the OSP (P = 0.040). The comparative biomechanical analysis of ASF and OSP in the cadaveric specimens also revealed a significantly lower load to failure of the ASF (P = 0.046). The experimental groups did not show significant differences regarding age, sex or bone microstructure.ConclusionsThe current study demonstrated that the OSP is biomechanically superior to the ASF, indicating higher stability. This study provides the basis for an alternative anterior treatment option for DFTII.

Malignant spinal lesions (MSLs) are frequently the first manifestation of malignant disease. Spinal care, diagnostic evaluation, and the initiation of systemic therapy are crucial for outcomes in patients (pts) with advanced cancer. However, histopathology (HP) may be time consuming. The additional evaluation of spinal lesions using cytopathology (CP) has the potential to reduce the time to diagnosis (TTD) and time to therapy (TTT). CP and HP specimens from spinal lesions were evaluated in parallel in 61 pts (CP/HP group). Furthermore, 139 pts in whom only HP was performed were analyzed (HP group). We analyzed the TTD of CP and HP within the CP/HP group. Furthermore, we compared the TTD and TTT between the groups. The mean TTD in CP was 1.7 ± 1.7 days (d) and 8.4 ± 3.6 d in HP (p < 0.001). In 13 pts in the CP/HP group (24.1%), specific therapy was initiated based on the CP findings in combination with imaging and biomarker results before completion of HP. The mean TTT in the CP/HP group was 21.0 ± 15.8 d and was significantly shorter compared to the HP group (28.6 ± 23.3 d) (p = 0.034). Concurrent CP for MSLs significantly reduces the TTD and TTT. As a result, incorporating concurrent CP for analyzing spinal lesions suspected of malignancy might have the potential to enhance pts’ quality of life and prognosis in advanced cancer. Therefore, we recommend implementing CP as a standard procedure for the evaluation of MSLs.

e14007 Background: Metastatic spinal lesions are the first manifestation of malignant disease in up to 30% of patients (pts). Spinal care, diagnostic evaluation and initiation of systemic therapy are crucial for outcome in pts with advanced cancer. Histopathology (HP) from bone specimens is time consuming and decalcification procedure can hamper diagnostic information. The additional evaluation of spinal lesions by cytopathology (CP) has the potential to reduce time to diagnosis (TTD) and time to therapy (TTT). Therefore, we performed simultaneous analysis of CP and HP specimens from suspected malignant spinal lesions to evaluate the diagnostic value of additional CP. This work was supported by the German Society for Spine Surgery (DWG). Methods: We obtained CP specimens by transpedicular, intralesional aspiration through a Yamshidi needle or touch preparation from solid tissue samples. CP and HP specimens from spinal lesions were evaluated in parallel in 54 pts (CP/HP group). We analyzed sensitivity and specificity of CP in reference to HP. Furthermore, we compared the TTD and TTT of CP/HP group with a retrospective cohort of 103 patients in whom only HP was performed (HP group). Results: The collection of CP samples was feasible without elongation of surgery time or any complications for the pts. In 52/54 (96%) pts a CP-specimen was successfully obtained. Of the 52 pts analyzed, multiple myeloma was diagnosed in 10 pts, solid malignancy in 34, 1 pt had lymphoma and 7 did not show malignancy. The most common solid malignancies were prostate cancer (n=9), breast cancer (n=5) and adenocarcinoma of the lung (n=5). The sensitivity and specificity of CP in reference to HP is 98% and 71%, respectively. The concordance of CP and HP in differentiating between hematologic or solid neoplastic lesions is 94.2%. TTD in the CP/HP group was significantly shorter compared to HP group (1.7±1.8 and 8.6±3.6 d, respectively; p<0.001). In addition, TTT in the CP/HP group was significantly shorter than in the HP group (19.3±14.4 d and 31.4±24.7 d; p=0.003). In 24.1% of pts a specific tumor therapy was initiated based on CP diagnosis before obtaining the results of HP. Conclusions: The evaluation of CP from malignant spinal lesions shows high sensitivity and concordance with HP and reduced TTD and TTT. Therefore, CP in addition to HP from spinal lesions of suspected malignancy has the potential to improve quality of life and prognosis in pts with advanced cancer. We therefore recommend the implementation of additional CP to HP in previously undiagnosed malignant spinal lesions.

Einleitung Zu Beginn eines septischen Schocks könnte eine Hyperoxie aufgrund einer Verbesserung des Sauerstoffdefizits und der Funktion der angeborenen Immunantwort Vorteile haben. Andererseits führt eine Hyperoxie zur vermehrten Bildung reaktiver Sauerstoffspezies sowie zur Vasokonstriktion und kann somit eine Sauerstofftoxizität verursachen. Wir postulierten, dass sich die optimalen Zielbereiche des Sauerstoffpartialdrucks im arteriellen Blut (PaO2) im Verlauf eines septischen Schocks ändern und untersuchten die Assoziation mit der Mortalität auf der Intensivstation.

Background: Patellar dislocation is a common injury in children and adolescents. There is a lack of information about concomitant osteochondral lesions in these patients. Hypothesis: We hypothesized that the likelihood of chondral or osteochondral lesions would increase with each prior patellar dislocation and that the appearance of lesions in surgically treated children and adolescents would be influenced by age, sex, injury mechanism, and body mass index (BMI). Study Design: Case-control study; Level of evidence, 3. Methods: Inclusion criteria were (1) age <18 years, (2) surgical treatment with diagnostic arthroscopy of the knee including description of chondral and osteochondral lesions, and (3) maximum time period between the last patellar dislocation and presentation in our department of 6 weeks and maximum of 4 weeks between presentation and surgery. A total of 153 children (173 knees) with a mean age of 13.0 ± 2.1 years were included. All surgical reports and intraoperative arthroscopic imaging were analyzed retrospectively for the location and severity of lesions. The likelihood of lesions was calculated with multiple stepwise regression models regarding injury mechanism, number of dislocations, sex, age, physeal closure, and BMI. Results: The regression model to predict femoral lesions was statistically significant (χ2[5] = 26.55; P < .001) and identified male sex, BMI ≥25, traumatic injury mechanism, and physeal closure as independent factors associated with the appearance of femoral lesions. The second regression model predicting the appearance of patellar lesions was also statistically significant (χ2[4] = 26.07; P < .001) and identified the traumatic injury mechanism as a single independent predictor for patellar lesions. Conclusion: BMI ≥25, male sex, and physeal closure were factors significantly associated with femoral chondral and osteochondral lesions in our cohort. In case of traumatic lateral patellar dislocation (LPD), the likelihood of patellar and femoral chondral and osteochondral lesions is significantly higher than in nontraumatic LPD. Early magnetic resonance imaging and surgical treatment should be considered in obese patients, male patients, and patients with physeal closure and after traumatic LPD.

Study Design: Retrospective Cohort Study Objectives: To investigate and compare the prevalence of low bone mineral density (BMD) and abnormal laboratory bone metabolism parameters in patients undergoing elective primary discectomy, decompression, and fusion and to outline possible differences in these parameters between patients undergoing revision for skeletal vs non-skeletal complications. Methods: We retrospectively evaluated BMD measurements by dual-energy x-ray absorptiometry (DXA) in 389 consecutive patients scheduled for elective lumbar spine surgery. Next to demographic characteristics, laboratory bone metabolism parameters were assessed. Group comparisons were performed between primary discectomy, decompression, and fusion. In patients scheduled for revision surgery after fusion, potential differences in the skeletal status between those with skeletal vs non-skeletal complications were analyzed. Results: Osteoporosis by T-score was detected in 6.7%, 11.0% and 14.7% of the patients undergoing discectomy, decompression and fusion, respectively. While vitamin D deficiency (67.6%) and hyperparathyroidism (16.4%) were frequently detected, no differences in laboratory bone metabolism markers could be found between the groups. Female sex (P<.001), higher age (P=.01) and lower BMI (P<.001) were associated with lower BMD. In the cohort of patients undergoing revision surgery due to complications after fusion, those with skeletal complications did not differ in BMD or bone metabolism from those with non-skeletal complications. Conclusions: Osteoporosis represents a relevant comorbidity in patients scheduled for elective spine surgery, which is why DXA should be routinely performed in these patients. However, DXA may provide limited information in identifying patients at increased risk for skeletal complications after fusion.

Background Retrograde drilling in osteochondrosis dissecans (OCD) is a widely used surgical intervention. A radiation-free electromagnetic navigation system (ENS)-based method was compared with the standard freehand fluoroscopic (SFF) method regarding clinical applicability. Methods We performed a clinical cohort study at a department of Orthopaedics in a Level 1 children’s hospital with 40 patients (20 SFF and 20 ENS). Retrograde drilling of the talar dome was used in patients with unstable medial OCD (MRI stage 2 according to Hepple’s revised classification; stage 2 according to the International Cartilage Repair Society). The outcome measurements were: (a) Intraoperative fluoroscopy exposure and length of surgery and (b) Postoperative serial follow-up MRIs every 6 months. Results 22 female and 18 male patients aged 13.8 ± 1.6 years (range: 11–17 years) were included. Using the ENS technique, length of surgery was significantly reduced to 20.2 ± 6.4 min compared to 36.1 ± 11.8 min (p < 0.01) for the SFF technique. The average x-ray radiation time for the SFF technique was 23.5 ± 13.5 sec and 1.9 ± 1.7 sec for the ENS technique ( p < 0.01). Radiation exposure was significantly reduced from 44.6 ± 19.7 mSv (SFF technique) to 5.6 ± 2.8 mSv (ENS technique) ( p < 0.01). Intraoperative perforation of cartilage occurred once in the SFF group. Correct placement of the drilling channel was verified in all patients on follow-up MRI after six months and a timely healing was seen after two years. Conclusions The ENS method provides for a significant reduction in length of surgery and radiation exposure. ENS was without intraoperative cartilage perforation. The clinical and radiological follow-up parameters are comparable for SFF- and ENS-guided retrograde drilling. Trial registration WF – 085/20, 05/2020 “retrospectively registered” https://www.aerztekammer-hamburg.org/ethik_kommission.html .

INTRODUCTION:Prostate cancer has a special predilection to form bone metastases. Despite the known impact of the microvascular network on tumour growth and its dependence on the organ-specific microenvironment, the characteristics of the tumour vasculature in bone remain unknown.METHODS:The cell lines LNCaP, DU145, and PC3 were implanted into the femurs of NSG mice to examine the microvascular properties of prostate cancer in bone. Tumour growth and the functional and morphological alterations of the microvasculature were analysed for 21 days in vivo using a transparent bone chamber and fluorescence microscopy.RESULTS:Vascular density was significantly lower in tumour-bearing bone than in non-tumour-bearing bone, with a marked loss of small vessels. Accelerated blood flow velocity led to increased volumetric blood flow per vessel, but overall perfusion was not affected. All of the prostate cancer cell lines had similar vascular patterns, with more pronounced alterations in rapidly growing tumours. Despite minor differences between the prostate cancer cell lines associated with individual growth behaviours, the same overall pattern was observed and showed strong similarity to that of tumours growing in soft tissue.DISCUSSION:The increase in blood flow velocity could be a specific characteristic of prostate cancer or the bone microenvironment.

BackgroundProstate cancer-related morbidity is associated with its preferential spread to the bone. Although the molecular interactions between the bone microenvironment and cancer cells have been researched extensively, the relevance of the microvascular properties of prostate cancer bone metastases remains largely unknown. Most preclinical studies focusing on microvascular analyses are based on heterotopic tumor implantation, whereas the impact of the microenvironment on site-specific growth behavior and angiogenesis is rarely addressed.MethodsThe microvascular changes associated with tumor growth in bone and soft tissue were characterized by implanting single cell suspensions of LnCap, Du145, and Pc3 cells into the femur (femur window) or striated muscle (dorsal skinfold chamber) of NSG mice. Tumor growth and the local microvasculature were analyzed for 21days using intravital fluorescence microscopy.ResultsThe results showed a higher engraftment of tumor cells in bone than in striated muscle associated with accelerated growth of LnCap cells and Pc3 cells. Permeability, blood flow, and tissue perfusion rates were greater in bone than in striated muscle. Du145 cells showed similar growth behavior in both tissues with similar vascular properties. The bone microenvironment facilitated tumor engraftment and growth. Increased microvascular density in striated muscle led to a higher tumor burden during early growth, whereas the increased perfusion promoted later prostate cancer growth in bone.ConclusionsMonitoring prostate cancer microcirculation in bone and soft tissue may be useful to evaluate the organ-specific efficacy of new treatments.

OBJECTIVE:The treatment of severe spinal deformities in pediatric patients is very challenging. Posterior only vertebral column resection (PVCR) allows for correcting of severe deformities of the vertebral column via a posterior only procedure. We analyzed radiologic outcome of PVCR performed on a series of pediatric patients with severe congenital and acquired spinal deformities. METHODS:A case series of 11 pediatric patients with severe spinal deformity who were treated by PVCR between 2009 and 2013 were retrospectively analyzed. All patients had posterior instrumentation and reconstruction of the anterior column with titanium cages filled with autologous bone. Seven patients had pure kyphosis or kyphoscoliosis, whereas 4 patients were treated because of scoliotic deformities. The patient records were reviewed for demographic and general clinical data. Complications and adverse events, transfusion rates, and surgical time were recorded. Radiologic analysis included Cobb angles and percentage of correction, analysis of sagittal profile, time to fusion, and possible complications related to instrumentation. RESULTS:Average preoperative scoliosis of 61° was corrected to 32°, resulting in a 50% correction at final follow-up. Coronal imbalance was improved to 36% at the most recent follow-up. Mean preoperative kyphotic deformity was 90° and was corrected to 43° at the last follow-up evaluation. Intraoperative complications included loss of the neuromonitoring signals in 2 cases and pleural laceration in 1 case. CONCLUSIONS:PVCR for children is an effective and safe technique providing a successful correction of complex pediatric spinal deformities. Nevertheless, it remains a technically highly demanding procedure, implying the possibility of severe complications.

PURPOSE: Pyogenic spondylodiscitis is a rare disease, but its incidence is increasing. Over the last decade, spinal surgery has been modified to become minimally invasive. In degenerative spinal disorders, such minimally invasive surgery (MIS) reduces blood loss, muscular trauma, and the hospital stay. However, it is not known whether MIS also confers these benefits to patients with pyogenic spondylodiscitis. This retrospective cohort study compared the safety and efficacy of MIS and the conventional open surgical procedure in patients with pyogenic spondylodiscitis.METHODS: The study cohort consisted of all consecutive patients who underwent surgery for thoracic or lumbar pyogenic spondylodiscitis that was not caused by previous surgery or tuberculosis in our tertiary-care institution between January 2003 and December 2011.RESULTS: Of the 148 eligible patients, 75 and 73 underwent MIS and open surgery, respectively. The 2 groups did not differ in terms of age, body mass index, American Society of Anaesthesiologists score, comorbidities, septic disease, or preoperative neurologic deficit. The 2 methods were associated with similar postoperative stays in the intensive care unit, overall hospital stays, complication rates, and postoperative survival. However, MIS was associated with a significantly shorter operating time, a lower perioperative need for blood products, and, as exCONCLUSIONS: Our 9-year experience suggests that MIS is safe and effective for spontaneous pyogenic thoracic and lumbar spondylodiscitis.

OBJECTIVE: Posterior-anterior spondylodesis is often used to stabilize the spine in various pathologies. The anterior procedure is often performed via thoracoscopy. It is unclear whether the anterior procedure should be performed immediately after posterior instrumentation or after the patient has convalesced. This retrospective study compared perioperative safety and morbidity in 1-stage versus 2-stage posterior-anterior fusion surgery with a thoracoscopic anterior approach. METHODS: All consecutive patients who underwent surgery for posterior-anterior spinal stabilization from 2006 to 2013 were included. American Society of Anesthesiologists score, preoperative and postoperative laboratory values, operation duration, blood loss, intensive care unit stay, pain, postoperative hospital stay, perioperative complications, and preoperative and postoperative Eastern Cooperative Oncology Group and Frankel scores were assessed. A subset of the cohort was selected by propensity score matching to eliminate possible selection bias. RESULTS: There were 247 patients who underwent 1-stage (n = 104) or 2-stage (n = 143) stabilization with thoracoscopic fusion. Spinal pathologies were fracture, malignancy, pyogenic spondylodiscitis, degenerative spinal disorders, and failed previous surgery. One-stage and 2-stage procedures were similar in terms of preoperative, surgical, and postoperative variables, including complication rates, except that the 1-stage procedure was associated with greater pain 2 days after surgery and shorter hospital stay. The propensity scoreematched cohort of 64 pairs yielded similar results with only 1-stage patients showing elevated visual analog scale score on postoperative day 2 (3.8 vs. 2.4, P = 0.043). CONCLUSIONS: One-stage stabilization was as safe as 2-stage stabilization and associated with shorter hospitalization. Greater pain after the 1-stage procedure, which resolved 30 days after surgery, reflects the fact that 2-stage patients already had pain relief when they underwent thoracoscopy.

Objectives Early diagnosis of traumatic brain injury and reliable prediction of outcome are essential for determining treatment strategies and allocating resources. This study re-evaluates the Eppendorf–Cologne Scale (ECS) and its predictive accuracy for outcome compared with the Glasgow Coma Scale (GCS). Methods A prospective cohort analysis of severely injured trauma patients registered in the Trauma Registry of the German Society for Trauma Surgery from 2012–2013 was carried out. Only directly admitted patients alive on admission with complete data on GCS, ECS and outcome in terms of survival to hospital discharge or death were included. The predictive accuracy in terms of the outcome of the ECS and the GCS was modelled using area under the receiver operating characteristic (AUROC) curve analysis. Results A total of 17 616 patients fulfilled the study inclusion criteria. The ECS outmatched the predictive accuracy of the GCS for outcome (AUROC, 0.853, 95% confidence interval, 0.831–0.854; and AUROC 0.836; 95% confidence interval, 0.825–0.848, respectively; P =0.062). An ECS score of 8 was associated with a 25-fold higher mortality compared with an ECS score of 0. Patients who had an ECS score of 8 had a 1.5-fold higher mortality compared with patients allocated a GCS score of 3. Conclusion The ECS shows a higher accuracy for prediction of outcome compared with the GCS and enables further differentiation within the critical GCS 3 collective.

Organ-specific microcirculation plays a central role in tumor growth, tumor cell homing, tissue engineering, and wound healing. Mouse models are widely used to study these processes; however, these mouse strains often possess unique microhemodynamic parameters, making it difficult to directly compare experiments. The full functional characterization of bone and striated muscle microcirculatory parameters in non-obese diabetic-severe combined immunodeficiency/y-chain; NOD-Prkds IL2rg (NSG) mice has not yet been reported. Here, we established either a dorsal skinfold chamber or femur window in NSG mice (n = 23), allowing direct analysis of microcirculatory parameters in vivo by intravital fluorescence microscopy at 7, 14, 21, and 28 days after chamber preparation. Organ-specific differences were observed. Bone had a significantly lower vessel density but a higher vessel diameter than striated muscle. Bone also showed higher effective vascular permeability than striated muscle. The centerline velocity values were similar in the femur window and dorsal skinfold chamber, with a higher volumetric blood flow in bone. Interestingly, bone and striated muscle showed similar tissue perfusion rates. Knowledge of physiological microhemodynamic values of bone and striated muscle in NSG mice makes it possible to analyze pathophysiological processes at these anatomic sites, such as tumor growth, tumor metastasis, and tumor microcirculation, as well as the response to therapeutic agents.

Objective Osteoarthritis (OA) is a major cause of musculoskeletal pain and disability worldwide. The investigation of disease-modifying treatment options for OA has become an important aspect of orthopedic care. To assess the effect of intra-articular and oral glucosamine sulfate (GS) versus placebo on osteoarthritis in a canine model. Materials In this randomized, placebo-controlled, double-blinded study, OA was induced by anterior cruciate ligament transection (ACLT) according to the Pond-Nuki model in 32 canines. All canines were allocated into 4 treatment subgroups with treatment administered for 8 weeks: GS (400 mg) intra-articular, placebo intra-articular, GS (200 mg/kg body weight) oral, and placebo oral. The contralateral nonoperated stifle (knee) served as control. After 8 weeks, the medial and lateral femoral condyles, the medial and lateral tibial plateau and patella were histologically examined and anatomic changes quantified by light microscopy using the modified Mankin score. Results After 8 weeks, mean Mankin score values significantly (P < 0.002) decreased in the intra-articular GS group (8.1; range 7.9-8.8) compared with the intra-articular placebo group (13.9; range 11.6-15.9) and again significantly (P < 0.002) in the oral GS group (12.1; range 9.9-12.7) compared with the oral placebo group (15.1; range 12.5-17.0). Mean Mankin score values were significantly (P < 0.002) lower in the intra-articular GS group compared with the oral GS group. Conclusion Both, intra-articular and oral administered GS significantly reduced histological signs of OA in the Pond-Nuki model, with the intra-articular application being more effective compared to oral administration.

OBJECTIVES:To compare the radiological and functional outcome after fixation of intertrochanteric fractures (IF) using either an integrated 2-screw cephalomedullary nail [InterTan (IT); Smith & Nephew] or a single-screw device [Gamma3 (G3); Stryker] with a 5-year follow-up.DESIGN:Prospective, randomized.SETTINGS:A single-center study.PATIENTS:One hundred four patients with a mean age of 81.2 ± 9.2 years were included, 33 patients were available for the final 5-year follow-up, 63 patients died, and 8 patients were lost for follow-up.INTERVENTION:Internal fixation of intertrochaneteric femur fractures using a cephalomedullary nail with either a single screw or an integrated 2-screw system.MAIN OUTCOME MEASUREMENTS:Length of hospital stay, SF-36-questionnaire, Harris-Hip-Score, radiographs.RESULTS:SF-36 index at 6 months indicated that 93% of the IT group returned to their prefracture status compared with only 80% in the G3 group. For the mental health SF-36 index, the IT patients showed a significant increased level 6 months after the index procedure (IT: P = 0.02; G3: P = 0.20). The length of hospital stay was significantly (P = 0.03) shorter in the IT group. After 5 years however, neither group had significant implant-related complications or differences in terms of functional outcome.CONCLUSIONS:Regarding functional outcome and hospital stay, the IT collective performed better in the 6-month follow-up. After 5 years, no significant differences were recorded.LEVEL OF EVIDENCE:Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Marfan syndrome (MFS) is a rare, severe, chronic, life-threatening disease with multiorgan involvement that requires optimal multidisciplinary care to normalize both prognosis and quality of life. In this article, each key team member of all the medical disciplines of a multidisciplinary health care team at the Hamburg Marfan center gives a personal account of his or her contribution in the management of patients with MFS. The authors show how, with the support of health care managers, key team members organize themselves in an organizational structure to create a common meaning, to maximize therapeutic success for patients with MFS. First, we show how the initiative and collaboration of patient representatives, scientists, and physicians resulted in the foundation of Marfan centers, initially in the US and later in Germany, and how and why such centers evolved over time. Then, we elucidate the three main structural elements; a team of coordinators, core disciplines, and auxiliary disciplines of health care. Moreover, we explain how a multidisciplinary health care team integrates into many other health care structures of a university medical center, including external quality assurance; quality management system; clinical risk management; center for rare diseases; aorta center; health care teams for pregnancy, for neonates, and for rehabilitation; and in structures for patient centeredness. We provide accounts of medical goals and standards for each core discipline, including pediatricians, pediatric cardiologists, cardiologists, human geneticists, heart surgeons, vascular surgeons, vascular interventionists, orthopedic surgeons, ophthalmologists, and nurses; and of auxiliary disciplines including forensic pathologists, radiologists, rhythmologists, pulmonologists, sleep specialists, orthodontists, dentists, neurologists, obstetric surgeons, psychiatrist/psychologist, and rehabilitation specialists. We conclude that a multidisciplinary health care team is a means to maximize therapeutic success.

Background and ObjectivesSurgical interventions can alter the balance between pro‐ and anti‐angiogenic growth factors and thereby modulate tumor growth. Since the microcirculatory properties of tumors underlie organ‐specific differences, the microhemodynamic characteristics of bone metastasis have not yet been fully described. Angiogenesis inhibitors are increasingly being used to treat advanced stages of cancer. We hypothesized that the anti‐angiogenic drug sunitinib abrogates alterations in microvascular properties following a minor surgical intervention in an in vivo model of secondary breast cancer growth in the bone.MethodsIntravital microscopy was performed over 25 days using a xenograft model of breast cancer tumor growth in the bone to determine changes in microvascular properties during sunitinib treatment. Mastectomy was performed on day 5 to evaluate the effect of a minor surgical trauma on tumor growth and microvascular properties.ResultsAnti‐angiogenic therapy resulted in reduced tumor growth, decreased vascular density, and increased vascular diameters. Blood flow velocity remained constant while microvascular permeability temporarily increased after the surgical intervention.ConclusionsAdministration of sunitinib reduced tumor growth and altered microcirculatory properties in a time‐dependent manner. The observed dramatic increase in microvascular permeability after the surgical intervention may have implications for local tumor growth, and metastatic dissemination. J. Surg. Oncol. 2016;113:515–521. © 2016 Wiley Periodicals, Inc.

Osteochondritis dissecans (OCD) represents an important clinical entity in orthopedic sports medicine. Once surgical intervention is required, retrograde drilling for OCD lesions remains technically challenging. A novel electromagnetic navigation system was developed to be a radiation-free navigation tool providing spatiotemporal real-time information to the surgeon without the need for a stationary patient tracker and without relevant setup and calibration times. The novel system was tested for arthroscopically assisted retrograde drilling of cadaveric OCD lesions of the knee and talus and compared with the gold standard fluoroscopy-guided retrograde drilling procedure in a controlled laboratory study setup. The novel method considerably improves on the standard operating procedure in terms of safety, operation time, and radiation exposure and will be available for further surgical indications.

Purpose: The aim of this cadaveric study was to evaluate the accuracy, feasibility, and operation time of a novel electromagnetic navigation system (ENS) and procedure for transclavicular-transcoracoid tunnel placement compared with a standard minimally invasive (SMI) reconstruction method for minimally invasive arthroscopically assisted anatomic acromioclavicular joint reconstruction. Methods: Ten arthroscopically assisted electromagnetic- navigated transclavicular-transcoracoid drilling procedures and 10 SMI procedures were performed on 10 human cadavers using 2 TightRope reconstructions (Arthrex, Naples, FL) for each site. Postoperative computed tomography scans were acquired to determine tunnel placement accuracy. Optimal coracoid tunnel placement was defined according to the anatomic insertions of the trapezoid and conoid ligaments with the oblong button placed in a center-base position at the coracoid undersurface without cortical breach or fracture. Both reconstruction procedures were performed without fluoroscopy. Results: Successful tunnel placement was accomplished in 98.8% using the ENS method and in 83.8% using the SMI procedure (P = .087). The mean overall operation time was 28.5 +/- 6.6 minutes for the ENS method and 35.2 +/- 3.9 minutes for the SMI method (P = .012). The ENS procedure required no directional readjustments or restarts. Drill misguidance with subsequent cortical breach occurred twice in the SMI group. In both groups no fractures were documented. Conclusions: In this descriptive laboratory study, both the ENS and the SMI techniques achieved the desired anatomic reconstruction. Compared with the SMI method, the ENS procedure showed higher accuracy, required a shorter operation time, and was associated with no complications.