M. Frink

The influence of hip rotation on femoral offset in plain radiographs.

Background and purpose — Adequate restoration of femoral offset (FO) is critical for successful outcome after hip arthroplasty or fixation of hip fracture. Previous studies have identified that hip rotation influences the projected femoral offset (FOP) on plain anteroposterior (AP) radiographs, but the precise effect of rotation is unknown. Patients and methods — We developed a novel method of assessing rotation-corrected femoral offset (FORC), tested its clinical application in 222 AP hip radiographs following proximal femoral nailing, and validated it in 25 cases with corresponding computed tomography (CT) scans. Results — The mean FORC was 57 (29–93) mm, which differed significantly (p < 0.001) from the mean FOP 49 (22–65) mm and from the mean femoral offset determined by the standard method: 49 (23–66) mm. FORC correlated closely with femoral offset assessed by CT (FOCT); the Spearman correlation coefficient was 0.94 (95% CI: 0.88–0.97). The intraclass correlation coefficient for the assessment of FORC by AP hip radiographs correlating the repeated measurements of 1 observer and of 2 independent blinded observers was 1.0 and 1.0, respectively. Interpretation — Hip rotation affects the FOP on plain AP radiographs of the hip in a predictable way and should be adequately accounted for.

Bone morphogenetic protein-7 enhances bone-tendon integration in a murine in vitro co-culture model.

PurposeBone-tendon healing following anterior cruciate ligament reconstruction is reportedly enhanced by bone morphogenetic protein (BMP)-7. To improve our understanding of the underlying biologic processes, we examined the effects of BMP-7 on region-specific gene expression in vitro.MethodsA murine in vitro co-culture model simulating the osteoblast, interface and fibroblast regions was established. The dose- and time-dependent region-specific effects of BMP-7 exposure on gene expression of Alpl, Bglap, Col1a1, Runx2 and Spp1 were analysed by quantitative PCR.ResultsAt the osteoblast region, BMP-7 significantly increased Alp, Bglap, Col1a1, and Runx2 expression, while Spp1 expression was suppressed. At the interface region, BMP-7 exposure resulted in a trend towards increased expression rates of Alpl and Col1a1, whereas Bglap (Pu2009<u20090.001) and Runx2 (Pu2009<u20090.01) were significantly upregulated without any detectable effect on Spp1 expression. At the fibroblast region, BMP-7 increased Alpl (Pu2009<u20090.001), Bglap (Pu2009<u20090.001) and Runx2 (Pu2009<u20090.001) expression, but no significant effects were seen on Col1a1 or Spp1. Exposure to BMP-7 (100xa0ng/ml) had its most pronounced biologic impact on day ten.ConclusionBMP-7 stimulation showed beneficial region-specific effects on bone-tendon healing in vitro, such as enhanced expression of parameters for ossification and fibroblast transdifferentiation, both key processes during successful graft integration.

[The TraumaNetzwerk DGU project. Goals, conception, and successes achieved].

In Germany, approximately 35,000 patients with major injuries are treated per year. The treatment of patients suffering from major injuries is both a medical and a logistic challenge. Despite the high-level quality of medical care, regional differences exist due to geographical and infrastructural conditions. In addition, discrepancies in human resources and technical equipment in hospitals influence diagnostics and treatment of severely injured patients. Based on these findings trauma networks of the German Trauma Association were founded to guarantee nationwide high-quality medical care of these patients. This article provides an overview about requirements of all involved professions and establishment of trauma networks considering state-of-the-art communication technology. Moreover, characteristics of the auditing and certification process and planning of the integration of rehabilitation facilities are described.ZusammenfassungPro Jahr werden in Deutschland etwa 35.000 schwerverletzte Patienten behandelt. Deren medizinische Versorgung stellt nicht nur medizinisch, sondern auch logistisch eine Herausforderung dar. Trotz einer allgemein hohen Versorgungsqualität gibt es regionale Unterschiede, die zum einen auf geografische und infrastrukturelle Gegebenheiten, aber auch auf Differenzen in der personellen und apparativen Ausstattung der Kliniken zurückzuführen sind. Auf diesen Erkenntnissen basierend wurde die Initiative TraumaNetzwerkxa0DGU® (DGU: Deutsche Gesellschaft für Unfallchirurgie) gegründet, um eine qualitativ hochwertige und flächendeckende medizinische Versorgung schwerverletzter Patienten zu gewährleisten. Dieser Beitrag gibt einen Überblick über die Erwartungen an ein Traumanetzwerk und beschreibt dessen Etablierung unter Berücksichtigung moderner Kommunikationstechnologie. Darüber hinaus werden Besonderheiten der Reauditierung und die geplante Einbindung von rehabilitativen Einrichtungen in die Traumanetzwerke dargestellt.AbstractIn Germany, approximately 35,000 patients with major injuries are treated per year. The treatment of patients suffering from major injuries is both a medical and a logistic challenge. Despite the high-level quality of medical care, regional differences exist due to geographical and infrastructural conditions. In addition, discrepancies in human resources and technical equipment in hospitals influence diagnostics and treatment of severely injured patients. Based on these findings trauma networks of the German Trauma Association were founded to guarantee nationwide high-quality medical care of these patients. This article provides an overview about requirements of all involved professions and establishment of trauma networks considering state-of-the-art communication technology. Moreover, characteristics of the auditing and certification process and planning of the integration of rehabilitation facilities are described.

Functional implications of femoral offset following hemiarthroplasty for displaced femoral neck fracture.

PurposeInadequate reconstruction of femoral offset after total hip arthroplasty (THA) is associated with unfavourable outcomes, but its importance following hemiarthroplasty for displaced femoral neck fracture is unknown.MethodsOur study examined the correlation between reconstructed femoral offset and functional outcome 12xa0months after post traumatic hemiarthroplasty in 126 prospectively enrolled elderly patients. Rotation-corrected femoral offset (FORC), relative femoral offset (FORL) and contralateral femoral offset (FOC) were measured on anteroposterior radiographs. The Harris Hip Score (HHS) was the primary outcome measure; the timed up and go (TUG) test and Lawton instrumental activities of daily living (IADL) score were secondary outcomes. Correlations were sought using the Spearman correlation coefficient (r). Sample size was calculated using an Altman nomogram, with the power set at 80xa0%, the significance level of 0.05 and a standardised difference of 0.75.ResultsThe mean reconstructed FORC was 41xa0mm (17–67xa0mm) and showed a linear relationship and excellent correlation with the FOC. At 12xa0months, we found a significant positive correlation between FORC and HHS (ru2009=u20090.303, pu2009=u20090.025) and IADL (ru2009=u20090.325, pu2009=u20090.013), but not TUG (ru2009=u2009−0.026, pu2009=u20090.863). These findings were confirmed by bivariate and multivariate correlation between FORL and functional outcome parameters.ConclusionsWe found a clinically relevant relationship between femoral offset and functional outcome after hemiarthroplasty in elderly patients, comparable with that of THA, for treating osteoarthritis.

Percutaneous dorsal instrumentation for thoracolumbar extension-distraction fractures in patients with ankylosing spinal disorders: a case series.

BACKGROUND CONTEXTnThoracolumbar extension-distraction fractures are rare injuries mainly restricted to patients suffering from ankylosing spinal disorders. The most appropriate surgical treatment of these unstable spinal injuries remains to be clarified.nnnPURPOSEnTo report on a cohort of 10 patients treated with closed reduction and percutaneous dorsal instrumentation.nnnSTUDY DESIGNnCase series.nnnPATIENT SAMPLEnTen consecutive patients with ankylosing spinal disorders and thoracolumbar extension-distraction fractures (Type B3 according to the AOSpine Thoracolumbar Spine Injury Classification System).nnnOUTCOME MEASURESnPostoperative reduction, alignment, and implant position were analyzed by computed tomography. Loss of reduction was assessed on lateral radiographs by using the Cobb technique. Ambulation ability and pain were assessed at follow-up.nnnMETHODSnMinimally invasive dorsal percutaneous instrumentation was performed in 10 consecutive patients (3 men, 7 women) with a mean age of 81.5 (range 72-90) years between May 2010 and December 2012. The mean postoperative follow-up time was 7.9 (range 4-28) months.nnnRESULTSnAll 10 patients were treated with closed reduction and dorsal instrumentation; in no case was conversion to an open approach required. The mean operation time was 60.2 (range 32-135) minutes. None of the patients presented neurologic deficits. Cement-augmented screws were implanted in two cases. Sufficient radiographic correction was achieved in all patients; no case of loss of reduction was noted at final follow-up. In one case, complete hardware removal was performed 9 months after the index operation because of persistent back pain at the level of the implant. One patient died of postoperative inferior vena cava obstruction. At discharge, all patients were able to ambulate without the need for crutches or opioid analgesics. At final follow-up, all patients ambulated with full weight bearing; four patients reported persistent back pain.nnnCONCLUSIONSnIn fragile patients with ankylosing spinal disorders and thoracolumbar extension-distraction fractures, closed reduction and percutaneous dorsal instrumentation provide a satisfying midterm functional outcome while minimizing perioperative risks compared with conventional dorsoventral procedures.

Femoral offset following trochanteric femoral fractures: a prospective observational study

BACKGROUNDnReconstruction of the femoral offset reportedly improves outcome following total hip arthroplasty, but little is known of its influence following hip fractures. We aimed to establish the effect of the femoral offset on the medium-term functional outcome in elderly patients who had sustained trochanteric fractures requiring proximal femoral nailing.nnnPATIENTS AND METHODSnWe measured the rotation corrected femoral offset (FORC) and relative femoral offset (FORL) on plain anteroposterior radiographs of the hip in 188 patients (58 male, 130 female) with a trochanteric fracture who underwent proximal femoral nailing at our institution. The primary outcome measure was the Harris hip score (HSS) 6 and 12 months postoperatively; the Barthel index was assessed as a secondary outcome.nnnRESULTSnThe mean FORC after surgery was 58 mm (±11 mm), while the mean FORL was 1.21 (±0.22). At final follow up, we found significant inverse relationships (Spearmans rank correlation coefficient, ρ) between FORC and FORL and the functional outcome assessed by the HSS (FORC: ρ = -0.207, p = 0.036; FORL: ρ = -0.247, p = 0.012), and FORL and the Barthel index (FORC: ρ = -147, p = 0.129; FORL: ρ = -0.192, p = 0.046). A consistent trend was observed after adjustment for confounding variables.nnnCONCLUSIONSnOur results underline the biomechanical importance of the femoral offset for medium-term outcomes in elderly patients with trochanteric fractures. In contrast with the published findings on total hip arthroplasty, we found an inverse correlation between functional outcome and the extent of the reconstructed femoral offset.nnnLEVEL OF EVIDENCEnLevel I - Prognostic study.

Agreement Between Proximal Femoral Geometry and Component Design in Total Hip Arthroplasty: Implications for Implant Choice

BACKGROUNDnThe present study aimed to analyze the agreement between proximal femoral geometry of adult hips and femoral component design in total hip arthroplasty.nnnMETHODSnAnatomical femoral offset (FOAnat) and the anatomical neck-shaft angle (NSAAnat) of 800 adult hips were measured by computed tomography scans, and anatomical femoral neck height (FHAnat) was calculated. Corresponding best-fit implants of the most common hip system (standard, high offset and varus variant) were identified for each hip. Finally, the precision of the best possible anatomic reconstruction was assessed.nnnRESULTSnThe mean FOAnat was 38.0 mm (range: 19.8-57.9 mm, standard deviation [SD]: 6.4 mm), the mean NSAAnat was 130.8° (range: 107.1°-151.9°; SD: 6.5°), and the mean FHAnat was 32.6 mm (range: 14.4-52.0 mm; SD: 5.5 mm). In 450 (56.3%) hips, the standard variant was identified to be the best-fit implant, followed by the varus (nxa0= 282, 35.3%) and the high offset (nxa0= 68, 8.5%) variants. The mean minimal distance from the best-fit implant was 4.5 mm (range: 0.1-20.2 mm, SD: 3.4 mm). Excellent agreement (distance: <2 mm) between hip anatomy and best-fit implant was found in 203 (25.4%) hips, combined excellent and acceptable agreement (distance: <6 mm) in 569 (71.1%) hips, whereas 213 (28.9%) hips were graded as poor (distance: ≥6 mm).nnnCONCLUSIONnThe present study revealed a mismatch between proximal femoral anatomy of a relevant proportion of adult hips and implant geometry of the most common femoral component in total hip arthroplasty.

Stimulation with bone morphogenetic protein-2 (BMP-2) enhances bone–tendon integration in vitro

ABSTRACT Purpose: Preclinical studies have reported that bone morphogenetic protein (BMP)-2 promotes bone–tendon healing following anterior cruciate ligament reconstruction. We examined the region-specific effects of BMP-2 on osteoblast and fibroblast differentiation in a highly standardized murine in vitro co-culture model of bone–tendon integration. Materials and methods: We used quantitative PCR to measure the dose- and time-dependent influence of BMP-2 on the expression of alkaline phosphatase, osteocalcin, collagen type 1 (alpha 1 chain), runt-related transcription factor 2, osteopontin, collagen type 1 (alpha 2 chain), collagen type 5 (alpha 1 chain), decorin, fibromodulin, mohawk homeobox, bone morphogenetic protein receptor, type 1A, bone morphogenetic protein receptor, type 2, and Noggin in the osteoblast, interface, and fibroblast regions of a co-culture model of the murine preosteoblast cell line MC3T3-E1 and the fibroblast cell line 3T6. Results: Stimulation with BMP-2 resulted in a significant upregulation of alkaline phosphatase (p < 0.001), osteocalcin (p < 0.001), collagens (p < 0.001), runt-related transcription factor 2 (p < 0.05), and osteopontin (p < 0.001) expression in the osteoblast region. In the interface region, BMP-2 exposure led to dose- and time-dependent upregulation of alkaline phosphatase (p < 0.001), osteocalcin (p < 0.001), osteopontin (p < 0.001), runt-related transcription factor 2 (p < 0.001), and markers of extracellular matrix production (p < 0.001). Both BMP receptors showed a significant BMP-2-dependent upregulation at the interface region, and Noggin was downregulated at the osteoblast and interface region following BMP-2 exposure. Conclusions: Exposure to BMP-2 upregulated the expression of genes associated with bone–tendon integration in vitro, suggesting the stimulation of transdifferentiation processes at the interface and fibroblast regions as well as the induction of positive feedback mechanisms. Further studies will be needed to establish BMP-2 dose and treatment algorithms following tendon reinsertion and reconstruction.

A porcine polytrauma model with two different degrees of hemorrhagic shock: outcome related to trauma within the first 48 h

AbstractBackgroundAn animal polytrauma model was developed, including trunk and extremity injuries combined with hemorrhagic shock and a prolonged post-traumatic phase. This could be useful for the assessment of different therapeutic approaches during intensive care therapy.MethodsA standardized polytrauma including lung contusion, liver laceration and lower leg fracture was applied in 25 pigs. They underwent controlled haemorrhage either with a blood volume loss of 45xa0% and a median arterial pressure (MAP) <30xa0mmHg/90xa0min (group L, nxa0=xa015) or a 50xa0% blood loss of and an MAP <25xa0mmHg/120xa0min (group H, nxa0=xa010). Five non-traumatized pigs served as a control (group C). Subsequently, intensive care treatment was given for an observational period of 48xa0h.ResultsBoth trauma groups showed signs of shock and organ injury (heart rate, MAP and lactate). The frequency of cardiopulmonary resuscitation (CPR) and lung injury was directly related to the severityn of the haemorrhagic shock (CPR—group L: 4 of 15 pigs, group H: 4 of 10 pigs; Respiratory failure—group L: 3 of 13, group H: 3 of 9. There was no difference in mortality between trauma groups.ConclusionThe present data suggest that our model reflects the mortality and organ failure of polytrauma in humans during shock and the intensive care period. This suggests that the experimental protocol could be useful for the assessment of therapeutic approaches during the post-traumatic period.

Das Polytrauma von Kindern und Jugendlichen

BACKGROUNDnThe number of (seriously) injured children increased again for the first time in 2011. The aim of this study was to analyse differences compared to multiple injured adults and to show the reality of daily treatment.nnnMETHODSnAll cases of the DGU Trauma Registry from the years 1997 to 2010 were examined. The documented cases were divided into different the age groups. The study investigated, e.g. the mechanism of accident, injury pattern, the number of hospital and ICU days, and lethality.nnnRESULTSnAt 38.8% the largest percentage of severely injured children and adolescents belongs to the group of 16-17 year olds. The group of 0-5 year olds (15.9%) has the lowest percentage. The most common accident cause was traffic accidents (58.5%). The mechanism of accident and the injury patterns changes with age. Younger patients are often treated in supraregional trauma centers (0-5 year olds: 78.2% vs. 16-17 year olds: 73.1% vs. >u200965 years: 63.2%). The average lethality rate was 14.8% (16.3% RISC).nnnCONCLUSIONSnThe percentage of severely injured children in the overall population is only 7.4%. Because the majority of patients are primarily treated in supraregional trauma centers, trauma centers with specialisation in paediatric traumatology are mandatory.ZusammenfassungHintergrundDie Anzahl der (schwer)verletzten Kinder ist 2011 erstmalig wieder angestiegen. Ziel der vorliegenden Studie war es, neben der Analyse der Unterschiede im Vergleich zum Polytrauma des Erwachsenen, auch die Versorgungsrealität abzubilden.MethodeEs wurden alle Fälle des TraumaRegisters DGU® der Jahre 1997–2010 untersucht. Die dokumentierten Fälle wurden in verschiedene Altersgruppen unterteilt. Die Auswertung umfasst Unfallhergang, Verletzungsmuster, Krankenhaus- und Intensivtage, Primärversorgung und Letalität.ErgebnisseMit 38,8u2009% stammt der größte Anteil der Kinder aus der Altersgruppe 16–17xa0Jahre, der geringste aus der Gruppe der ≤u20095-Jährigen (15,9u2009%). Die häufigste Unfallsache waren Verkehrsunfälle (58,5u2009%). Unfallursache und Verletzungsmuster waren abhängig vom Alter. Je jünger die Patienten, desto häufiger wurden sie primär in überregionalen Traumazentren behandelt (≤u20095-Jährige: 78,2u2009% vs. 16- bis 17-Jährige: 73,1u2009% vs. >u2009u200965xa0Jahre: 63,2u2009%). Die durchschnittliche Letalität betrug 14,8u2009% bei einem RISC- („Revised Injury Severity Classification-) Score von 16,3.SchlussfolgerungDer Anteil schwerverletzter Kinder am Gesamtkollektiv beträgt lediglich 7,4u2009%. Da der größte Teil in überregionalen Traumazentren versorgt wird, ist zu fordern, dass eine kindertraumatologische Kompetenz in den entsprechenden Traumazentren vorzuhalten ist.AbstractBackgroundThe number of (seriously) injured children increased again for the first time in 2011. The aim of this study was to analyse differences compared to multiple injured adults and to show the reality of daily treatment.MethodsAll cases of the DGU Trauma Registry® from the years 1997 to 2010 were examined. The documented cases were divided into different the age groups. The study investigated, e.g. the mechanism of accident, injury pattern, the number of hospital and ICU days, and lethality.ResultsAt 38.8u2009% the largest percentage of severely injured children and adolescents belongs to the group of 16–17xa0year olds. The group of 0–5xa0year olds (15.9u2009%) has the lowest percentage. The most common accident cause was traffic accidents (58.5u2009%). The mechanism of accident and the injury patterns changes with age. Younger patients are often treated in supraregional trauma centers (0–5xa0year olds: 78.2u2009% vs. 16–17xa0year olds: 73.1u2009% vs. >u200965xa0years: 63.2u2009%). The average lethality rate was 14.8u2009% (16.3u2009% RISC).ConclusionsThe percentage of severely injured children in the overall population is only 7.4u2009%. Because the majority of patients are primarily treated in supraregional trauma centers, trauma centers with specialisation in paediatric traumatology are mandatory.