Kilian Reising

Dose Reduction Does Not Affect Detection of Bone Marrow Lesions with Dual-energy CT Virtual Noncalcium Technique

RATIONALE AND OBJECTIVES The aim of this study was to evaluate if a dose-reduced, dose-neutral dual-energy computed tomographic (CT) virtual noncalcium technique can equally detect posttraumatic bone marrow lesions (BMLs) of the knee. MATERIALS AND METHODS Fifty patients underwent DE CT imaging with either a standard dose (group A) or a dose equal to that of a single-energy CT scan (group B) (28% dose reduction) and magnetic resonance imaging for knee trauma workup. Calcium was virtually subtracted from the images. Two radiologists rated the presence of abnormal soft tissue-like attenuation in the bone marrow in a total of 12 femoral and tibial regions and performed Hounsfield unit measurements thereafter. Receiver-operating characteristic curve analysis was used for four-point rating scores and Hounsfield unit measurements. Fractures were classified. RESULTS Magnetic resonance imaging depicted 170 BMLs (35 femoral, 135 tibial). Mean age, number of fractures, attenuation values and number of regions with BMLs were not significantly different between the groups. Visual rating revealed overall areas under the curves of 0.983 and 0.979 for observers 1 and 2, respectively. Visual judgment was superior to attenuation measurements for femoral regions regardless of the dose applied. Analysis of variance of all CT values revealed a significant influence for the presence of edema (P < .001) but no differences for the radiation dose used (P = .424). Interobserver agreement was excellent (κ = 0.944). CONCLUSIONS Dose reduction does not affect the detectability of posttraumatic BMLs with a dual-energy CT virtual noncalcium technique, thereby providing potential additional information compared with single-energy CT imaging without additional radiation dose.

Particulate cartilage under bioreactor-induced compression and shear

PurposeOur aim was to explore the effect of varying in vitro culture conditions on general chondrogenesis of minced cartilage (MC) fragments.MethodsMinced, fibrin-associated, bovine articular cartilage fragments were cultured in vitro within polyurethane scaffold rings. Constructs were maintained either free swelling for two or four weeks (control), underwent direct mechanical knee-joint-specific bioreactor-induced dynamic compression and shear, or they were maintained free swelling for two weeks followed by two weeks of bioreactor stimulation. Samples were collected for glycosaminoglycan (GAG)/DNA quantification; collagen type I, collagen type II, aggrecan, cartilage oligomeric matrix protein (COMP), proteoglycan-4 (PRG-4) messenger RNA (mRNA) analysis; histology and immunohistochemistry.ResultsCellular outgrowth and neomatrix formation was successfully accomplished among all groups. GAG/DNA and collagen type I mRNA were not different between groups; chondrogenic genes collagen type II, aggrecan and COMP revealed a significant downregulation among free-swelling constructs over time (week two through week four). Mechanical loading was able to maintain chondrogenic expression with significantly stronger expression at long-term time points (four weeks) in comparison with four-week control. Histology and immunohistochemistry revealed that bioreactor culture induced stronger cellular outgrowth than free-swelling constructs. However, weaker collagen type II and aggrecan expression with an increased collagen type I expression was noted among this outgrowth neotissue.ConclusionsThe method of MC culture is feasible under in vitro free-swelling and dynamic loading conditions, simulating in vivo posttransplantation. Mechanical stimulation significantly provokes cellular outgrowth and long-term chondrogenic maturation at the mRNA level, whereas histology depicts immature neotissue where typical cartilage matrix is expected.

Intertrochantäre Femurfrakturen im Kindesalter

ZusammenfassungIntertrochantäre Femurfrakturen sind seltene Verletzungen im Kindesalter. Anhand zweier Fallbeispiele beschreiben wir die Verletzung und diskutieren Therapieoptionen auf der Basis eigener Erfahrungen und von Literaturrecherchen. Aufgrund der Muskelansätze und daraus resultierenden Kräften im Bereich des proximalen Femur ist die operative Stabilisierung einer konservativen Therapie in der Regel vorzuziehen. Wir empfehlen dazu die Verwendung einer winkelstabilen Platte, welche postoperativ eine sofortige Mobilisierung mit Vollbelastung ermöglicht.AbstractBased on two cases and a review of the literature, we describe a rare injury in childhood, intertrochanteric femoral fracture. Because of the insertion and traction of muscles at the proximal femur, conservative treatment is difficult. The hip muscles pull the proximal fragment into flexion, abduction and external rotation. In our opinion, surgical stabilization is the therapy of choice. We use an angular stable, locking compression plate for the stabilization of these fractures. Postoperatively, mobilization with full weight bearing is possible.

Intertrochanteric femoral fractures in children

ZusammenfassungIntertrochantäre Femurfrakturen sind seltene Verletzungen im Kindesalter. Anhand zweier Fallbeispiele beschreiben wir die Verletzung und diskutieren Therapieoptionen auf der Basis eigener Erfahrungen und von Literaturrecherchen. Aufgrund der Muskelansätze und daraus resultierenden Kräften im Bereich des proximalen Femur ist die operative Stabilisierung einer konservativen Therapie in der Regel vorzuziehen. Wir empfehlen dazu die Verwendung einer winkelstabilen Platte, welche postoperativ eine sofortige Mobilisierung mit Vollbelastung ermöglicht.AbstractBased on two cases and a review of the literature, we describe a rare injury in childhood, intertrochanteric femoral fracture. Because of the insertion and traction of muscles at the proximal femur, conservative treatment is difficult. The hip muscles pull the proximal fragment into flexion, abduction and external rotation. In our opinion, surgical stabilization is the therapy of choice. We use an angular stable, locking compression plate for the stabilization of these fractures. Postoperatively, mobilization with full weight bearing is possible.

Outcome and risk factors in children after traumatic cardiac arrest and successful resuscitation

INTRODUCTION Prospective collected data of the TraumaRegister DGU(®) were analyzed to derive survival rates and predictors for non-survival in the children who had suffered traumatic cardiorespiratory arrest. Different time points of resuscitation efforts (only preclinical, in the emergency room (ER) or preclinical+ER) were analyzed in terms of mortality and neurological outcome. METHODS The database of the TraumaRegister DGU(®) comprising 122,742 patients from 1993 to 2013 was analyzed. The main focus of this survey was on the paediatric group defined by an age ≤ 14 years who could be compared to adults. Different statistical analysis (univariate and multivariate analysis, logistic regression) were performed with mortality as the target variable. Differences between the paedatric group and adults were analysed by Fishers exact test. RESULTS Data after preclinical and/or ER resuscitation from 152 children and 1690 adults were analyzed. A good or moderate outcome (GOS 5+4) was found in 19.4% of the childrens group compared to 12.4% of the adults (p=0.02). Analysis of the GOS 5+4 subgroups after preclinical resuscitation only revealed that these outcomes were achieved by 19.4% of the paediatric group and 13.2% of the adults (p=0.24), after ER-only resuscitation by 37.0% of the children and 19.6% of the adults (p=0.046), and after preclinical and ER resuscitation by only 10.9% of the children compared to 2.5% of the adults (p=0.006). Taking only survivors into account, 84.8% of the children and 62% of the adults had a GOS 4+5. The highest risk for mortality in the logistic regression model was associated with preclinical intubation, followed by GCS 3, blood transfusion and severe head injury with AIS ≥3 and ISS. CONCLUSIONS CPR in children after severe trauma seems to yield a better outcome than in adults, and appears to be more justified than the current guidelines would imply. Resuscitation in the ER is associated with better neurological outcomes compared with resuscitation in a preclinical context or in both the preclinical phase and the ER. Our childrens outcomes seem to be better than those in most of the earlier studies, and the data presented might support algorithms in the future especially for paediatric resuscitation.

Radiological evaluation of the posterior pelvic ring in paediatric patients: Results of a retrospective study developing age- and gender-related non-osseous baseline characteristics in paediatric pelvic computed tomography – References for suspected sacroiliac joint injury

INTRODUCTION The prevalence of paediatric pelvic injury is low, yet they are often indicative of accompanying injuries, and an instable pelvis at presentation is related to long-term poor outcome. Judging diastasis of the sacroiliac joint in paediatric pelvic computed tomography is challenging, as information on their normal appearance is scarce. We therefore sought to generate age- and gender-related standard width measurements of the sacroiliac joint in children for comparison. PATIENTS AND METHODS A total of 427 pelvic computed tomography scans in paediatric patients (<18 years old) were retrospectively evaluated. After applying exclusion criteria, 350 scans remained for measurements. Taking a standard approach we measured the sacroiliac joint width bilaterally in axial and coronal planes. RESULTS We illustrate age- and gender-related measurements of the sacroiliac joint width as a designated continuous 3rd, 15th, 50th, 85th and 97th centile graph, respectively. Means and standard deviations in the joint width are reported for four age groups. There are distinct changes in the sacroiliac joints appearance during growth. In general, male children exhibit broader sacroiliac joints than females at the same age, although this difference is significant only in the 11 to 15-year-old age group. CONCLUSION The sacroiliac joint width in children as measured in coronal and axial CT scans differs in association with age and gender. When the sacroiliac joint width is broader than the 97th centile published in our study, we strongly encourage considering a sacroiliac joint injury.

Comparison of Multidetector Computed Tomography and Flat-Panel Computed Tomography Regarding Visualization of Cortical Fractures, Cortical Defects, and Orthopedic Screws: A Phantom Study.

Abstract To compare the visualization of cortical fractures, cortical defects, and orthopedic screws in a dedicated extremity flat-panel computed tomography (FPCT) scanner and a multidetector computed tomography (MDCT) scanner. We used feet of European roe deer as phantoms for cortical fractures, cortical defects, and implanted orthopedic screws. FPCT and MDCT scans were performed with equivalent dose settings. Six observers rated the scans according to number of fragments, size of defects, size of defects opposite orthopedic screws, and the length of different screws. The image quality regarding depiction of the cortical bone was assessed. The gold standard (real number of fragments) was evaluated by autopsy. The correlation of reader assessment of fragments, cortical defects, and screws with the gold standard was similar for FPCT and MDCT. Three readers rated the subjective image quality of the MDCT to be higher, whereas the others showed no preferences. Although the image quality was rated higher in the MDCT than in the FPCT by 3 out of 6 observers, both modalities proved to be comparable regarding the visualization of cortical fractures, cortical defects, and orthopedic screws and of use to musculoskeletal radiology regarding fracture detection and postsurgical evaluation in our experimental setting.

Minimally invasive stabilization of distal humerus fractures: A pilot study with biomechanical evaluation

BACKGROUND Fracture of the distal humerus is a fairly rare injury and makes high demands on the treating surgeon. Prerequisites for a good outcome are anatomical reconstruction and osteosynthesis stable enough for exercises. A method permitting early restoration of function is especially important for patients with osteoporosis. The extensive surgical approach necessary for open reduction is associated with a high number of wound healing disorders and infections with a frequency of 11% being reported in the literature. Although open reduction and internal fixation in double-plating technique is unavoidable for complex intraarticular fractures, an alternative, minimally invasive and, consequently, tissue-preserving procedure is desirable for simpler fractures. OBJECTVE To investigate this issue further an angular stable nail system developed for the distal radius was implanted as a stabilizer and the construct tested biomechanically as part of a feasibility study. METHODS Distal humerus fractures were stabilized by insertion of a distal radius nail, namely, the Targon DR (Aesculap, Tuttlingen) and a K-wire. To test the hypothesis six cadaveric bones fixed in formalin were tested biomechanically for displacement, implant failure, and stiffness. Displacement was determined by means of an ultrasound-based system. RESULTS An average displacement of 1.6 mm ± 0.7 was recorded at a maximum compression force of 100 N in extension and an average displacement of 1.4 mm ± 0.9 in flexion. Implant failure was not observed for any of the constructs. CONCLUSIONS The study presented here permits the conclusion that a minimally invasive procedure is possible at the distal humerus and does ensure adequate stability. Although the nail was not specifically designed for the humerus, current findings form the basis for a promising approach that will be pursued further after modification of the nail design.

Biomechanical testing of an innovative fixation procedure to stabilize olecranon osteotomy.

For the treatment of distal humerus an approach involving olecranon osteotomy is frequently preferred as it offers a clearer view, especially in cases of complex intraarticular fractures. It is however associated with the high risk of osteotomy-related complications such as nonunion, delayed healing, implant failure and migration of wires. The aim of the present study was to evaluate the stability of different new procedures that stabilize olecranon osteotomy compared with conventional tension band wiring. We hypothesize that the new implants provide equivalent stability as the conventional tension band wiring. To test the hypothesis 27 biomechanically evaluated synthetic ulnae were osteotomized and stabilized with either the application of tension band wiring, the Olecranon Hook LCP (Synthes, Switzerland), or the Olecranon Osteotomy nail (Synthes, Switzerland). Loading was performed providing a tensile load to simulate the tensile force applied by the triceps muscle. Cyclic force-controlled loading was performed at 300 alternating forces between 10N and 500N at a speed of 200N/sec. An ultrasound-based system measured displacement to an accuracy of 0.1 mm. Statistical analysis showed significantly less displacement in the Olecranon Hook LCP and Olecranon Osteotomy nail groups compared with tension banding. Comparison of plate and nail yielded no differences in stability. Biomechanical testing did however show significantly higher stability for newer fixation methods for olecranon osteotomies compared with the frequently applied technique of tension band wiring. Whether the use of these implants will also lower complication rates remains to be evaluated in future clinical studies. Level of evidence: Basic Science Study, Biomechanical Study.

Age- and severity-adjusted treatment of proximal humerus fractures in children and adolescents—A systematical review and meta-analysis

Background Fractures of the proximal humerus in patients under the age of 18 years show a low incidence; existing clinical studies only comprise small patient numbers. Different treatment methods are mentioned in the literature but a comparison of the outcome of these methods is rarely made. Up to now, no evidence-based algorithm for conservative and operative treatment is available. The aim of this systematic review with meta-analysis was therefore to gather the best evidence of different treatment methods and their associated functional outcome, complication rates, rates of limb length discrepancies and radiological outcome. Methods and findings The OVID database was systematically searched on September 30th in 2016 in order to find all published clinical studies on the subject of proximal humerus fractures of patients ≤18 years. Exclusion criteria were previously defined. The Coleman Methodology Score was used to evaluate the quality of the single studies. 886 studies have been identified by the search strategy. 19 studies with a total of 643 children (mean age: 11.8 years) were included into the meta-analysis with a mean Coleman Methodology Score of 71 ± 7.4 points. 18 of the 19 studies eligible for inclusion were retrospective ones, of the best quality available (mean follow-up ≥ 1 year, mean follow-up rate ≥ 65%). 56% of the patients were male. Proximal humerus fractures were treated conservatively in 41% and surgically in 59% of the cases (Elastic Stable Intramedullary Nailing (ESIN): 31%; K-wires: 20%; 8% other methods, e.g. plate osteosynthesis, olecranon traction). The overall success rate (good/excellent outcome) for all treatment methods was 93%. The success rate of ESIN (98%) and of K- wire fixation (95%) was significantly higher (p = 0.01) than the success rate of conservative treatment options (91%). A subgroup analysis of severely displaced fractures (Neer grade III/IV, angulation ≥ 20°) resulted in a change of success rates, to the disadvantage of conservative treatment methods (conservative treatment 82%, ESIN 98%, K-wires 95%; p < 0.001). Complication rates did not differ to a significant extent. 9% of the complications occurred in the patients treated by K-wire fixation, 8% if a conservative treatment option was chosen and 7% in the fractures that were stabilized by ESIN. A change from a one-nail technique to a two-nail technique reduced the complication rate of ESIN significantly. Follow-up X- rays without residual deformity could be found in 96% of the patients treated by ESIN, a rate which was higher than in the patients treated conservatively (93%) or by K-wire fixation (88%). The rate of arm length discrepancies at final follow- up was lower if the fractures were stabilized by ESIN (4%) than if they were treated conservatively (9%) or by K-wires (19%). An evaluation of age-dependent treatment options was performed. Conclusions By performing this meta-analysis an evidence-based treatment algorithm could be introduced to treat the fractures according to the severity of displacement and according to the patients age. For severely displaced fractures ESIN is the method of choice, with the best clinical and radiological outcome.