Minimal-invasive anterior approach to the hip provides a better surgery-related and early postoperative functional outcome than conventional lateral approach after hip hemiarthroplasty following femoral neck fractures.

INTRODUCTION: Femoral neck fractures (FNF) are one of the most frequent fractures among elderly patients and commonly require surgical treatment. Bipolar hip hemiarthroplasty (BHHA) is mostly performed in these cases. MATERIAL AND METHODS: In the present retrospective study geriatric patients with FNF (n = 100) treated either by anterior minimal-invasive surgery (AMIS; n = 50) or lateral conventional surgery (LCS; n = 50) were characterized (age at the time of surgery, sex, health status/ASA score, walking distance and need for walking aids before the injury) and intraoperative parameters (duration of surgery, blood loss, complications), as well as postoperative functional performance early (duration of in-patient stay, radiological leg length discrepancy, ability to full weight-bearing, mobilization with walking aids) and 12 months (radiological signs of sintering, clinical parameters, complication rate) after surgery were analyzed. RESULTS: Patients in the AMIS group demonstrated a reduced blood loss intraoperatively, while the duration of surgery and complication rates did not differ between the two groups. Further, more patients in the AMIS group achieved full weight-bearing of the injured leg and were able to walk with a rollator or less support during their in-patient stay. Of interest, patients in the AMIS group achieved this level of mobility earlier than those of the LCS group, although their walking distance before the acute injury was reduced. Moreover, patients of the AMIS group showed equal leg lengths postoperatively more often than patients of the LCS group. No significant differences in functional and surgery-related performance could be observed between AMIS and LCS group at 12 months postoperatively. CONCLUSIONS: In conclusion, geriatric patients treated by AMIS experience less surgery-related strain and recover faster in the early postoperative phase compared to LCS after displaced FNF. Hence, AMIS should be recommended for BHHA in these vulnerable patients.

Does the implant make the difference ? - Prospective comparison of two different proximal femur nails.

The aim of this study was to compare two proximal femur nails with regard to the complication rate and midterm clinical outcome : the InterTAN nail (ITN) versus the third generation gamma nail (GN). 78 patients older than 60 years with an unstable intertrochanteric femoral fracture (AO/OTA 31 A2/A3) were randomised over a 20 month period into either ITN (n = 39) or GN (n = 39). The outcomes of interest were the perioperative implant-related complications and the functional status (Harris Hip Score) at 6 months postoperatively. In 14 of the ITN and in two of the GN procedures the surgeons rated the implant as cumbersome (p = 0.002). Functional outcome and complication rate did not differ between both groups. The mechanical failure correlated with the positioning of the lag screw independent on the used implant. The surgeon's technique (closed reduction, positioning of lag screw) and not implant configuration, is of crucial importance in achieving successful outcome.

[Complex pelvic traumas : data linkage of the German Pelvic Injury Register and the TraumaRegister DGU®]. / Das komplexe Beckentrauma : Matching des Beckenregisters DGU mit dem TraumaRegister DGU®.

BACKGROUND: Complex pelvic traumas, i.e., pelvic fractures accompanied by pelvic soft tissue injuries, still have an unacceptably high mortality rate of about 18 %. PATIENTS AND METHODS: We retrospectively evaluated an intersection set of data from the TraumaRegister DGU® and the German Pelvic Injury Register from 2004-2009. Patients with complex and noncomplex pelvic traumas were compared regarding their vital parameters, emergency management, stay in the ICU, and outcome. RESULTS: From a total of 344 patients with pelvic injuries, 21 % of patients had a complex and 79 % a noncomplex trauma. Complex traumas were significantly less likely to survive (16.7 % vs. 5.9 %). Whereas vital parameters and emergency treatment in the preclinical setting did not differ substantially, patients with complex traumas were more often in shock and showed acute traumatic coagulopathy on hospital arrival, which resulted in more fluid volumes and transfusions when compared to patients with noncomplex traumas. Furthermore, patients with complex traumas had more complications and longer ICU stays. CONCLUSION: Prevention of exsanguination and complications like multiple organ dysfunction syndrome still pose a major challenge in the management of complex pelvic traumas.

[Anterior approaches to the pelvic ring]. / Anteriore Zugänge zum Beckenring.

Anterior approaches for the stabilization of anterior and also posterior B and C type instability of the pelvic ring were the standard procedures before minimally invasive percutaneous methods supported by image intensifiers or navigation devices were established. Anterior approaches are currently still of high relevance for difficult or impossible closed reductions in multiple trauma surgery where the patient must remain in a supine position. They are also used for stabilization of an increasing number of osteoporotic fractures in the elderly which are no longer only treated in specialized pelvic trauma centres. The anterior as well as the posterior part of the pelvic ring can be stabilized via various anterior approaches. A Pfannenstiel incision is appropriate for plating of ruptures of the pubic symphysis and can be extended to a modified Stoppa approach if necessary. Fractures of the iliac wings can be approached either laterally or less traumatically, via an anterolateral approach. The latter equates the lateral window of the ilioinguinal approach to the acetabulum, allows visualization of the entire sacroiliac joint and therefore stabilization of not only iliosacral luxation but also luxated fractures with a small iliac fragment. By a combination of the different approaches it is possible to simultaneously stabilize ventral and dorsal instabilities in type C fractures of the pelvic ring with a minimal amount of iatrogenic soft tissue trauma. Although the described anterior approaches are considered as simple exact knowledge of the endangered structures and general risks for each approach are essential for a safe exposure of the anatomical region addressed.

The effect of an infra-acetabular screw for anatomically shaped three-dimensional plate or standard plate designs in acetabulum fractures: a biomechanical analysis.

BACKGROUND: Various plate shapes and implant configurations are used for stabilization of acetabulum fractures via anterior approaches. Little is known about the biomechanical stability of a two-dimensionally shaped "conventional" plate ("J-Plate"-JP) in comparison to three-dimensionally shaped plate configurations (3DP). In addition, the augmentary effect of an infra-acetabular lag-screw (IACS) fixation for anterior column and posterior hemi-transverse acetabulum fractures has not been clarified in comparison of JP and 3DP constructs. This study analyzed the difference between the biomechanical stability of JP compared to 3DP and the role of an IACS in a standardized acetabular fracture model in a single-leg stance loading configuration. METHODS: In an artificial bone substitute pelvis model (Synbone© Malans, Switzerland), a typical and standardized fracture pattern (anterior column and posterior hemi-transverse) was created with osteotomy jigs. After anatomic reduction the stabilization was performed using JP or 3DP. Eight pelvises per group were axially loaded in a single-leg stance model up to 400 N. After the load cycle, an additional infra-acetabular screw was placed and the measurement repeated. Fragment displacement was recorded by an optical tracking system (Optitrack Prime 13®, Corvallis, USA). RESULTS: In the pure placement, 3DP provided significantly superior stability when compared to JP. Augmentation of JP by IACS increased the stability significantly, up to the level of 3DP alone, whereas augmentation of the 3DP did not result in further increase of overall stability. CONCLUSION: The anatomically shaped plate alone provides a superior biomechanical stability in fixation of an anterior column and posterior hemi-transverse fracture model. In a JP fixation the augmentation by IACS provides similar strength as the anatomically shaped 3DP. By use of the anatomically shaped 3DP the need of a clinically risky application of IACS might be avoidable. LEVEL OF EVIDENCE: IV, Experimental study.

[Acetabular fractures in the elderly. Outcome of open reduction and internal fixation]. / Osteosynthese bei Acetabulumfrakturen im Alter. Ist eine Rekonstruktion sinnvoll?

The aim of this study was to analyze the clinical outcome and incidence of hip arthritis in elderly patients with acetabular fractures. Because of poor bone quality in the elderly, even a low-energy trauma may lead to an acetabular fracture. An anatomical reconstruction of the acetabulum is necessary to achieve sufficient stability also for a potential hip arthroplasty. So far, there is very limited information on the outcome of acetabular fractures in the elderly. During a period of 6 years (2001-2006), 48 patients older than 60 years were admitted to our department with an acetabular fracture. Thirty-nine patients were treated operatively and nine patients non-operatively. Twenty-nine operatively treated patients were followed up. Nineteen of them were assessed using EQ-5D, SF-12 and Merle d'Aubigné questionnaires in addition to their clinical examination. Ten other surgical patients were only examined using the questionnaires. Of the 29 patients that were followed up, 5 underwent total hip arthroplasty due to secondary post-traumatic hip arthritis after open reduction and internal fixation (ORIF). The range of motion of the operated hip was comparable to that of the non-operated contralateral side. However, the internal rotation was found to be slightly decreased at the operated side when compared to the non-operated contralateral side. Merle d'Aubigné score and physical and mental SF-12 score components as well as quality of life were better in patients treated with ORIF compared to those patients that were treated by secondary hip arthroplasty. Regarding the different treatment strategies (ORIF vs primary hip arthroplasty vs non-operative treatment) of acetabular fractures in the elderly, data from the literature are conflicting. Our results indicate that ORIF represents a good treatment option for acetabular fractures in the elderly. In patients that did not develop secondary hip arthritis, a good clinical outcome and quality of life was documented.

Operative treatment of 733 patients with acute thoracolumbar spinal injuries: comprehensive results from the second, prospective, Internet-based multicenter study of the Spine Study Group of the German Association of Trauma Surgery.

The second, internet-based multicenter study (MCSII) of the Spine Study Group of the German Association of Trauma Surgery (Deutsche Gesellschaft für Unfallchirurgie) is a representative patient collection of acute traumatic thoracolumbar (T1-L5) injuries. The MCSII results are an update of those obtained with the first multicenter study (MCSI) more than a decade ago. The aim of the study was to assess and bring into focus: the (1) epidemiologic data, (2) surgical and radiological outcome, and (3) 2-year follow-up (FU) results of these injuries. According to the Magerl/AO classification, there were 424 (57.8%) compression fractures (A type), 178 (24.3%) distractions injuries (B type), and 131 (17.9%) rotational injuries (C type). B and C type injuries carried a higher risk for neurological deficits, concomitant injuries, and multiple vertebral fractures. The level of injury was located at the thoracolumbar junction (T11-L2) in 67.0% of the case. 380 (51.8%) patients were operated on by posterior stabilization and instrumentation alone (POSTERIOR), 34 (4.6%) had an anterior procedure (ANTERIOR), and 319 (43.5%) patients were treated with combined posteroanterior surgery (COMBINED). 65% of patients with thoracic (T1-T10) and 57% with lumbar spinal (L3-L5) injuries were treated with a single posterior approach (POSTERIOR). 47% of the patients with thoracolumbar junction (T11-L2) injuries were either operated from posterior or with a combined posterior-anterior surgery (COMBINED) each. Short angular stable implant systems have replaced conventional non-angular stable instrumentation systems to a large extent. The posttraumatic deformity was restored best with COMBINED surgery. T-spine injuries were accompanied by a higher number and more severe neurologic deficits than TL junction or L-spine injuries. At the same time T-spine injuries showed less potential for neurologic recovery especially in paraplegic (Frankel/AISA A) patients. 5% of all patients required revision surgery for perioperative complications. Follow-up data of 558 (76.1%) patients were available and collected during a 30-month period from 1 January 2004 until 31 May 2006. On average, a posterior implant removal was carried out in a total of 382 COMBINED and POSTERIOR patients 12 months after the initial surgery. On average, the rehabilitation process required 3-4 weeks of inpatient treatment, followed by another 4 months of outpatient therapy and was significantly shorter when compared with MCSI in the mid-1990s. From the time of injury until FU, 80 (60.6%) of 132 patients with initial neurological deficits improved at least one grade on the Frankel/ASIA Scale; 8 (1.3%) patients deteriorated. A higher recovery rate was observed for incomplete neurological injuries (73%) than complete neurological injuries (44%). Different surgical approaches did not have a significant influence on the neurologic recovery until FU. Nevertheless, neurological deficits are the most important factors for the functional outcome and prognosis of TL spinal injuries. POSTERIOR patients had a better functional and subjective outcome at FU than COMBINED patients. However, the posttraumatic radiological deformity was best corrected in COMBINED patients and showed significantly less residual kyphotic deformity (biseg GDW -3.8° COMBINED vs. -6.1° POSTERIOR) at FU (p = 0.005). The sagittal spinal alignment was better maintained when using vertebral body replacement implants (cages) in comparison to iliac strut grafts. Additional anterior plate systems did not have a significant influence on the radiological FU results. In conclusion, comprehensive data of a large patient population with acute thoracolumbar spinal injuries has been obtained and analyzed with this prospective internet-based multicenter study. Thus, updated results and the clinical outcome of the current operative treatment strategies in participating German and Austrian trauma centers have been presented. Nevertheless, it was not possible to answer all remaining questions to contradictory findings of the subjective, clinical outcome and corresponding radiological findings between different surgical subgroups. Randomized-controlled long-term investigations seem mandatory and the next step in future clinical research of Spine Study Group of the German Trauma Society.

[Post-traumatic torticollis in a schoolchild: fracture, congenital anomaly or age-appropriate radiological findings of the atlas?]. / Posttraumatischer Tortikollis beim Schulkind : Fraktur, angeborene Fehlbildung oder altersentsprechender Normalbefund des Atlasbogens?

We describe the case of a 6-year-old girl with post-traumatic torticollis after falling on her head. The suspected fractures of the dens axis and/or atlas were ruled out after performing CT and MRI examinations as well as dynamic fluoroscopy. Radiological findings showed no further instability but there was a congenital non-fusion of the posterior arch and an age-appropriate non-fused anterior arch of the atlas. In addition to discoligamental injuries and fractures, congenital anomalies and normal variants of the immature anatomy of the cervical spine should also be considered in the diagnosis of the pediatric cervical spine after trauma.

[Operative treatment of traumatic fractures of the thoracic and lumbar spinal column. Part I: epidemiology]. / Operative Behandlung traumatischer Frakturen der Brust- und Lendenwirbelsäule: Teil I: Epidemiologie.

The Spine Study Group (AG WS) of the German Trauma Association (DGU) has now been in existence for more than a decade. Its main objective is the evaluation and optimization of the operative treatment for traumatic spinal injuries. The authors present the results of the second prospective internet-based multicenter study (MCS II) of the AG WS in three consecutive parts: epidemiology, surgical treatment and radiologic findings and follow-up results. The aim of the study was to update and review the state-of-the art for treatment of spinal fractures for thoracic and lumbar spine (T1-L5) injuries in German-speaking countries: which lesions will be treated with which procedure and what differences can be found in the course of treatment and the clinical and radiological outcome? This present first part of the study outlines the new study design and concept of an internet-based data collection system. The epidemiologic findings and characteristics of the three major treatment subgroups of the study collective will be presented: operative treatment (OP), non-operative treatment (KONS), and patients receiving a kyphoplasty and/or vertebroplasty without additional instrumentation (PLASTIE). A total of 865 patients (OP n=733, KONS n=52, PLASTIE n=69, other n=7) from 8 German and Austrian trauma centers were included. The main causes of accidents in the OP subgroup were motor vehicle accidents 27.1% and trivial falls 15.8% (KONS 55.8%, PLASTIE 66.7%). The Magerl/AO classification scheme was used and 548 (63.3%) compression fractures (type A), 181 (20.9%) distraction injuries (type B), and 136 (15.7%) rotational injuries (type C) were diagnosed. Of the fractures 68.8% were located at the thoracolumbar junction (T11-L2). Type B and type C injuries carried a higher risk for concomitant injuries, neurological deficits and additional vertebral fractures. The average initial VAS spine score, representing the status before the trauma, varied between treatment subgroups (OP 80, KONS 75, PLASTIE 72) and declined with increasing patient age (p<0.01).

[Operative treatment of traumatic fractures of the thorax and lumbar spine. Part II: surgical treatment and radiological findings]. / Operative Behandlung traumatischer Frakturen der Brust- und Lendenwirbelsäule. Teil II: Operation und röntgenologische Befunde.

The Spine Study Group (AG WS) of the German Trauma Association (DGU) presents its second prospective Internet-based multicenter study (MCS II) for the treatment of thoracic and lumbar spinal injuries. This second part of the study report focuses on the surgical treatment, course of treatment, and radiological findings in a study population of 865 patients. A total of 158 (18,3%) thoracic, 595 (68,8%) thoracolumbar, and 112 (12,9%) lumbar spine injuries were treated. Of these, 733 patients received operative treatment (OP group). Fifty-two patients were treated non-operatively and 69 patients were treated with kyphoplasty/vertebroplasty without additional instrumentation (Plasty group). In the OP group, 380 (51.8%) patients were instrumented from a posterior (dorsal) position, 34 (4.6%) from an anterior (ventral) position, and 319 (43.5%) cases with a combined posteroanterior procedure. Angular stable internal spine fixator systems were used in 86-97% of the cases for posterior and/or combined posteroanterior procedures. For anterior procedures, angular stable plate systems were used in a majority of cases (51.1%) for the instrumentation of mainly one or two segment lesions (72.7%). In 188 cases (53,3%), vertebral body replacement implants (cages) were used and were mainly implanted via endoscopic approaches (67,4%) to the thoracic spine and/or the thoracolumbar junction. The average operating time was 152 min in posterior-, 208 min in anterior-, and 298 min in combined postero-anterior procedures (p<0,001). The average blood loss was highest in combined operations, measuring 959 ml vs. 650 ml in posterior vs. 534 ml in anterior operations (p<0,001).Computer-assisted intraoperative navigation systems were used in 95 cases. At the time of hospital admission, 58,7% of the patients had spinal canal narrowing of an average of 36% (5-95%) at the level of their injury. The average spinal canal narrowing in patients with a complete spinal cord injury (Frankel/ASIA A) was calculated to be 70%, vs. 50% in patients with incomplete neurologic deficits (Frankel/ASIA B-D), and 20% in patients without neurologic deficits (Frankel/ASIS E; p<0,001). The average procedure in the plasty treatment subgroup was 50 min (18-145 min) to address one (n=59) or two (n=10) injured vertebral bodies. In patients with nonoperative treatment mainly three-point-corsets (n=36) were administered for a duration of 6-12 weeks. During their hospital stay 93 of 195 (44,7%) patients with initial neurologic deficits improved at least one Frankel/ASIA grade until the day of discharge. Two patients (0,2%) showed a neurologic deterioration. The highest rate of complete spinal cord injury (n=36, 23%) was associated with thoracic spine injuries. Nine (1%) patients died during the initial course of treatment. A total of 105 (14,3%) cases with intraoperative (n=56) and/or postoperative complications (n=69) were registered. The most common intraoperative complication was bleeding (n=35, 4,8%). A higher relative frequency of intraoperative complications was noticed in combined (n=34, 10,7%) vs. isolated posterior (n=22, 5,9%; p=0,021) procedures. The most common postoperative complication was associated with wound healing problems in 14 (1,9%) patients. Except in the non-operative treatment subgroup, a correction of the posttraumatic measured radiological deformity was achieved to a different extent within every treatment subgroup. There were no statistically significant differences between the postoperative radiological results of the treatment subgroups (dorsal vs. combination), taking into consideration the influence of relevant parameters such as different fracture types, patient age, and the amount of posttraumatic deformity (p=0,34, ANOVA).

[Operative treatment of traumatic fractures of the thoracic and lumbar spinal column: Part III: Follow up data]. / Operative Behandlung traumatischer Frakturen der Brust- und Lendenwirbelsäule: Teil III: Nachuntersuchung.

In this third and final part, the Spine Study Group (AG WS) of the German Trauma Association (DGU) presents the follow-up (NU) data of its second, prospective, internet-based multicenter study (MCS II) for the treatment of thoracic and lumbar spinal injuries including 865 patients from 8 trauma centers. Part I described in detail the epidemiologic data of the patient collective and the subgroups, whereas part II analyzed the different methods of treatment and radiologic findings. The study period covered the years 2002 to 2006 including a 30-month follow-up period from 01.01.2004 until 31.05.2006. Follow-up data of 638 (74%) patients were collected with a new internet-based database system and analyzed. Results in part III will be presented on the basis of the same characteristic treatment subgroups (OP, KONS, PLASTIE) and surgical treatment subgroups (Dorsal, Ventral, Kombi) in consideration of the level of injury (thoracic spine, thoracolumbar junction, lumbar spine). After the initial treatment and discharge from hospital, the average duration of subsequent inpatient rehabilitation was 4 weeks, which lasted significantly longer in patients with persistent neurologic deficits (mean 10.9 weeks) or polytraumatized patients (mean 8.6 weeks). Following rehabilitation on an inpatient basis, subsequent outpatient rehabilitation lasted on average 4 months. Physical therapy was administered significantly longer to patients with neurologic deficits (mean 8.7 months) or type C injuries (mean 8.6 months). The level of injury had no influence of the duration of the inpatient or outpatient rehabilitation. A total of 382 (72.2%) patients who were either operated from posterior approach only or in a combined postero-anterior approach had an implant removal after an average 12 months. During the follow-up period 56 (8.8%) patients with complications were registered and of these 18 (2.8%) had to have surgical revision. The most common complications reported were infection, loss of correction, or implant-associated complications. Clinical data showed a 2.9 higher relative risk for smokers compared to non-smokers to suffer from wound healing problems. The neurologic status of 81 (60.4%) out of 134 patients with neurologic deficits at the time of injury improved until follow-up. Neurologic deterioration was documented in 8 (1.3%) cases. Complete neurologic deficits after injury to the thoracic spine improved in 9% of the cases, whereas 59% of the cases with complete neurologic deficit improved after injury to the thoracolumbar junction. The surgical approach (posterior or combined postero-anterior) had no significant influence on neurological results at follow-up. Patient age, sex and neurologic deficits showed a statistically significant influence (p<0.05) on the fingertip-floor distance (FBA) at follow-up. Patient back function improved during the follow-up period. More than 2 years after the time of injury 32.2% of the patients had no complaints with respect to back function. The relative frequency of patients with unrestrained back function was greater after posterior surgery (24.2%), than anterior surgery (13.8%), or combined surgery (17.3%) (p=0.005; chi(2)-test). At follow-up there were no statistically significant differences of unrestrained back function between different levels of injury (thoracic spine 17.4%, TL junction 22.5% and lumbar spine 13.6%). The relative frequency of patients with injury to the thoracolumbar junction who reported "no complaints from the anterior approach" at follow-up, was calculated to be 55.6% after open versus 63.8% after endoscopic approaches with no significant differences. Of the patients 56.3% reported no donor site morbidity following iliac crest bone harvesting. The VAS spine score at follow-up was calculated within different treatment subgroups: OP 58.4 points, KONS 59.8 points, and PLASTIE 59.7 points. Statistically significant differences of the VAS spine score between posterior (64.9 points) versus combined surgery (47.8 points) were only verified at the level of injury of the thoracic spine (p=0.004). The relative frequency of patients regaining at least 80% of the initial score level was OP (posterior 60.4%, anterior 61.1%, combined 51.4%), 52.9% KONS and 67.6% PLASTIE. After surgery the mean period of incapacity from work was 4 months. Patients with a sedentary occupation before the time of injury were fully reintegrated into work in 71.1% of the cases. Patients with a physical occupation were fully reintegrated in 38.9% of the cases at follow-up. At follow-up 87 (31.2%) patients after posterior and 50 (20.1%) after combined surgery had no restrictions to their recreational activities (p=0.001). Treatment subgroups PLASTIE and KONS show a similar radiological result at follow-up with a bisegmental kyphotic deformity (GDW) of -9 degrees and -8.5 degrees, respectively. With all operative methods it was possible to correct or partly correct the posttraumatic kyphotic deformity. Until follow-up there was a loss of correction depending on the surgical approach and level of injury. Combined postero-anterior stabilization gave statistically significant better radiological results with less kyphotic deformity (-3.8 degrees) than posterior stabilization alone (-6.1 degrees) (p=0.005; ANOVA). Thus combined surgery was superior in its capability to restore spinal alignment within the observational period. At follow-up the use of titanium vertebral body replacement implants (cages) to reconstruct and support the anterior column showed significantly better radiological results with less kyphotic deformity and loss of correction (GDW 0.3 degrees) than the use of iliac bone strut grafts (-3.7 degrees ) (p<0.001). Neither additional anterior plates nor the combination of anterior plates with a cage or bone graft had a statistically significant influence on the kyphotic deformity measured at follow-up. A matched-pair analysis of anterior surgery alone versus combined surgery for the treatment of compression fractures (type A) at the thoracolumbar junction showed a significantly greater intraoperative blood loss but better radiological results in terms of monosegmental and bisegmental kyphotic deformity after combined surgery (p<0.05). A matched-pair analysis of treatment results between non-operative and operative treatment for burst fractures (type A3.1-2) showed a period of inability to work (6 months) which was twice as long for the non-operative treatment group. At the same time significantly better radiological results at follow-up were achieved after operative treatment of these fractures (p<0.05).

Rapamycin affects early fracture healing in mice.

BACKGROUND AND PURPOSE: The immunosuppressive drug rapamycin (RAPA) prevents rejection in organ transplantation by inhibiting interleukin-2-stimulated T-cell division. Rapamycin has also been suggested to possess strong anti-angiogenic activities linked to a decrease in production of vascular endothelial growth factor (VEGF). Angiogenesis and VEGF are thought to play a crucial role in fracture healing and as osteoporotic and traumatic fractures are common complications in immunosuppressed, organ transplantation patients, we conducted this study to analyze the effect of rapamycin treatment on bone repair. EXPERIMENTAL APPROACH: We investigated the effect of rapamycin treatment on bone repair in a murine closed femur fracture model using radiological, histomorphometric, immunohistochemical, biomechanical and protein biochemical analyses. KEY RESULTS: X-ray analyses demonstrated that rapamycin treatment inhibits callus formation after two weeks of fracture healing. The radiologically observed lack of callus formation was confirmed by histomorphometric analyses, which revealed a significantly diminished callus size and a reduced amount of bone formation when compared with vehicle-treated controls. Biomechanical testing further demonstrated that rapamycin significantly reduces torsional stiffness of the callus. Interestingly, this effect was associated with decreased vessel formation; a diminished proliferation of osteoblasts, endothelial cells and periosteal cells; and a reduced VEGF expression in hypertrophic chondrocytes. After five weeks treatment, however, the negative impact of rapamycin on fracture healing was overcome. CONCLUSIONS AND IMPLICATIONS: Thus, rapamycin initially delays fracture healing, most probably by inhibiting cell proliferation and neovascularization in the callus. These undesirable effects should be considered when rapamycin is administered to patients sustaining bone fractures.

A new technique for internal fixation of femoral fractures in mice: impact of stability on fracture healing.

Mouse models are of increasing interest to study the molecular aspects of fracture healing. Because biomechanical factors greatly influence the healing process, stable fixation of the fracture is of interest also in mouse models. Unlike in large animals, however, there is a lack of mouse models which provide stable osteosynthesis. The purpose of this study was therefore to develop a technique for a more stable fixation of femoral fractures in mice and to analyze the impact of stability on the process of fracture healing. The new technique introduced herein includes an intramedullary pin and an extramedullary metallic clip. Ex vivo biomechanical analysis revealed a significantly higher implant stiffness of our pin-clip technique when compared with previously described intramedullary fixation techniques. In vivo, we studied the course of healing after the more stable fixation with our pin-clip technique and compared the results with that observed after unstable fixation with the pin-clip technique after cutting the clip. After 2 and 5 weeks of fracture healing radiological analysis demonstrated that the more stable fixation with the pin-clip technique results in a significantly higher union rate compared to the unstable fixation. Torsional stiffness at 5 weeks was almost 3-fold of that measured after unstable fixation. Histomorphological analysis further showed that fractures stabilized with the pin-clip technique healed with a smaller periosteal callus area, an increased fraction of bone and a reduced amount of fibrous tissue. Of interest, the pin-clip fixation showed reliable union after 5 weeks, whereas the unstable pin fixation did not regularly achieve adequate fracture healing. In conclusion, we introduce a novel, easily applicable internal osteosynthesis technique in mice, which provides rotational stability after femoral fracture fixation. We further show that a more stable osteosynthesis significantly improves the process of fracture healing also in mice.

Monoclonal antibody to tumor necrosis factor-alpha modulates hepatocellular Ca2+ homeostasis during hemorrhagic shock in the rat.

Tumor necrosis factor-alpha (TNF-alpha) is a key mediator of shock-induced cellular and humoral inflammatory cascades. The present study investigated the role of TNF-alpha in oxidative membrane injury and altered hepatocyte Ca2+ regulation, both of which are critical steps in cellular dysfunction during ischemia/reperfusion events. Hemorrhagic shock was induced by bleeding male Sprague-Dawley rats (200-250 g, n=6/group) to a mean arterial blood pressure of 40 mmHg for 60 min. Rats were resuscitated with 60% of shed blood and twice the shed blood volume as Ringers' lactate. At the end of hemorrhage and 60 min after resuscitation, hepatocytes were isolated by liver collagenase perfusion. Hepatocyte Ca2+ uptake (Ca2+up) and Ca2+ membrane flux (Ca2+flux) were determined by 45Ca2+ incubation techniques. Hepatocyte reduced/oxidized glutathione and lipid peroxidation were determined fluorometrically. Both hemorrhage and hemorrhage/resuscitation significantly increased hepatocyte Ca2+up and Ca2+flux. The monoclonal chimeric mouse gamma1 TNF-alpha antibody (TN3gamma1.19.12; 20 mg/kg b.w.) given with resuscitation significantly decreased hepatocyte Ca2+up and Ca2+flux and prevented hepatocyte lipid peroxidation. These findings suggest that oxidative membrane injury could be the result of TNF-alpha modulation of hepatocellular Ca2+ regulation during hemorrhage/resuscitation.

Oxyradical-mediated hepatocellular Ca2+ alterations during hemorrhagic shock and resuscitation.

Both altered Ca2+ homeostasis and injury by oxygen-free radicals (OFR) are pivotal mechanisms of cellular dysfunction. The purpose of this study was to evaluate the role of OFR and xanthine oxidase in hepatocellular Ca2+ dysregulation following hemorrhagic shock and resuscitation. Anesthetized rats were bled to a mean arterial blood pressure of 40 mm Hg for 60 min and then resuscitated with 60% of shed blood and 3-fold the shed blood volume as lactated Ringer's for another 60 min. Total Ca2+ uptake (Ca2+(up)), rate of Ca2+ influx (Ca2+(in)), and membrane Ca2+(flux) (Ca2+(flux)) were determined in isolated hepatocytes using 45Ca2+ incubation techniques. Hepatocyte oxidant injury was fluorometrically determined by thiobarbituric acid-reactive substances, oxidized, and reduced glutathione. Hemorrhage/resuscitation significantly increased Ca2+(up), Ca2+(in), and Ca2+(flux) compared with sham-operated rats. Continuous administration of superoxide dismutase or catalase (60,000 IU/kg body weight) during resuscitation substantially decreased Ca2+(up), Ca2+(in), Ca2+(flux), and oxidant injury. Pretreatment with allopurinol (50 mg/kg/day for 2 days) significantly inhibited enhanced plasma xanthine oxidase activity and hepatocyte glutathione oxidation, however, it did not prevent hepatocellular Ca2+ dysregulation. These data suggested a significant role of oxyradicals in ischemia/reperfusion-induced Ca2+ overload, however, xanthine oxidase activation seemed not to be a main source of these radicals.

[New aspects for minimally invasive interventions in orthopedic trauma surgery]. / Neue Aspekte für minimal invasive Eingriffe in der Unfallchirurgie.

The minimally invasive method has gained complete acceptance for the treatment of diaphyseal fractures. In the majority of cases, this procedure is combined with stabilization of the fracture with insertion of an intramedullary implant. In cases of metaphyseal fracture, use of minimally invasive techniques depends on the extent of simultaneous involvement of the articular surface. For joint fractures, the main goal is anatomic reconstruction. At the same time as these less invasive surgical procedures and markedly improved methods of visualization have evolved, the implants themselves have also advanced. The standard implant of the future for plate osteosynthesis will be the interlocking plate. Minimally invasive surgical techniques will certainly continue to gather ground in the future for the entire field of accident surgery. Reduction of the surgical approach means less postoperative pain for the patient, earlier mobilization, and shortening of hospital stay and the whole process of rehabilitation.

[Fractures of the acetabulum: complications and joint replacement]. / Azetabulumfrakturen: Komplikationen und Endoprothetik.

Acetabular fractures assume a special role amongst the fractures of the pelvis, because they involve a major weight-bearing joint. As those fractures mostly result from exposure to great force, and because of their location in an anatomically complex region, a high rate of complications has to be anticipated. Besides general and perioperative complications long-term consequences, especially post-traumatic arthrosis, are relevant problems when it comes to treating fractures of the acetabulum. The primary reconstruction of the acetabulum, as well as a possibly necessary prosthetic replacement of the hip joint, makes high demands on the diagnostic and operative capabilities of the attending physician. Exact knowledge of the specific risks and pitfalls for each type of fracture and for the specific surgical techniques is crucial for a successful treatment. Due to the much worse long-term outcome when compared to primary total hip replacement in patients with osteoarthritis, acetabular fractures should, regardless of the patient's age, whenever possible be treated by operative reconstruction.

Proper coding of the Abbreviated Injury Scale: can clinical parameters help as surrogates in estimating blood loss?

PURPOSE: The Abbreviated Injury Scale (AIS) requires the estimation of the lost blood volume for some severity assignments. This study aimed to develop a rule of thumb for facilitating AIS coding by using objective clinical parameters as surrogate markers of blood loss. METHODS: Using the example of pelvic ring fractures, a retrospective analysis of TraumaRegister DGU(®) data from 2002 to 2011 was performed. As potential surrogate markers of blood loss, we recorded the hemoglobin (Hb) level, systolic blood pressure (SBP), base excess (BE), Quick's value, units of packed red blood cells (PRBCs) transfused before intensive care unit (ICU) admission, and mortality within 24 h. RESULTS: We identified 11,574 patients with pelvic ring fractures (Tile/OTA classification: 39 % type A, 40 % type B, 21 % type C). Type C fractures were 73.1 % AISpelvis 4 and 26.9 % AISpelvis 5. Type B fractures were 47 % AISpelvis 3, 47 % AISpelvis 4, and 6 % AISpelvis 5. In type C fractures, cut-off values of <7 g/dL Hb, <90 mmHg SBP, <-9 mmol/L BE, <35 % Quick's value, >15 units PRBCs, and death within 24 h had a positive predictive value of 47 % and a sensitivity of 62 % for AISpelvis 5. In type B fractures, these cut-off values had poor sensitivity (48 %) and positive predictive value (11 %) for AISpelvis 5. CONCLUSIONS: We failed to develop a rule of thumb for facilitating a proper future AIS coding using the example of pelvic ring fractures. The estimation of blood loss for severity assignment still remains a noteworthy weakness in the AIS coding of traumatic injuries.

[Practical courses for students can not only improve the teaching quality but can also increase the attractiveness of orthopaedic and trauma surgery]. / Praktische, berufsrelevante Kurse für Studierende können nicht nur die Lehre verbessern, sondern steigern auch die Attraktivität des Faches Orthopädie/Unfallchirurgie.

BACKGROUND: Students often complain about a lack of teaching of practical skills. This may be a cause for the low attractiveness of surgical disciplines. We therefore established a practical course to improve teaching quality to inspire the students for orthopedic and trauma surgery. METHODS: The platforms of the course included the teaching and acquisition of suture techniques, arthroscopy and osteosynthesis techniques. A total of 119 students participated in 9 courses and performed a detailed evaluation. RESULTS: The main motivation to participate was (i) to acquire practical skills (93 %), (ii) to learn about orthopaedic and trauma surgery (66 %) and (iii) to facilitate decision-making for the occupational choice (21 %). 94 % judged the quality of the course as "excellent", and all 119 participants indicated that they would recommend the course to other students. 43 of 45 students, who had not yet decided on their occupational choice, indicated that the course stimulated them for a career in orthopaedic and trauma surgery. CONCLUSION: This course not only can improve the teaching quality but also can increase the attractiveness of muskuloskeletal surgery.

The posterior two-portal approach for reconstruction of scapula fractures: results of 39 patients.

The purpose of this study was to describe the so-called posterior two-portal approach to the scapula in detail and to investigate the clinical outcome of patients with displaced glenoid and scapular neck fractures who were surgically treated using this approach. From February 1992 to August 2008, 39 patients (30 men and nine women; mean age: 53 years) with scapular fractures underwent surgical fixation at our institution. Thirty-three patients had glenoid fractures and six had unstable scapular neck fractures. All patients were treated via the two-portal approach. The reduction was evaluated radiographically, and the clinical results were analysed using the Constant score. The mean follow-up period was 78 months (range: 6-168). In 24 of the 33 glenoid fractures, the reduction was anatomical. The mean Constant score was 82.3 (range: 35-100) points. In one case, an early postoperative wound infection was cured by local revision, and one patient developed posttraumatic osteoarthritis of the acromioclavicular joint after 2 years. Only one patient developed specific glenohumeral degeneration after non-anatomical reduction. The posterior two-portal approach allows for a good visualisation of the posterior scapular neck and the glenoid area, facilitating the reduction and safe internal fixation of dislocated scapular neck and glenoid fractures.