Do we need to fix the anterior fracture component in insufficiency fractures of the pelvis? A biomechanical comparison on an FFP type IIIc fracture in an osteoporotic pelvic bone model.

There is a growing understanding of the specific characteristics of insufficiency fractures of the pelvis and of general requirements for the treatment of affected patients with focus on early mobilization and effective pain reduction as the main goals of therapy. While there is consensus on the significance of achieving stability of the dorsal pelvic ring structures there is still an open discussion about the potential benefits of additional stabilization of an anterior fracture component. Within a biomechanical test setup, two established methods of dorsal fracture fixation were tested under axial loading (25-1200 N; 1000 test cycles) on an explicit osteoporotic bone model (n = 32) with a standardized FFP type IIIc fracture with and without additional fixation of the anterior fracture component. Dorsal fixation was performed with and long and a short 7.3 mm cannulated screw in S1 in one group (n = 16), and a trans sacral bar with an additional short 7.3 mm cannulated screw in S1 in the other group (n = 16). Half of the samples received a 7.3 mm cannulated retrograde transpubic screw for anterior fixation. The fixation with the trans sacral bar and the additional anterior screw fixation showed the highest rate of stability (p = 0.0014), followed by the double SI-screw fixation with stabilization of the anterior fracture (p = 0.0002). During testing, we observed the occurrence of new sacral fractures contralateral to the initial fracture in 22/32 samples. The results let us assume that stabilization of an additional anterior fracture component relevantly improves the stability of the entire ring construct and might prevent failure of the dorsal stabilization or further fracture progression.

The effect of losartan on the development of post-traumatic joint stiffness in a rat model.

Post-traumatic joint stiffness (PTJS) is accompanied by a multidimensional disturbance of joint architecture. Pharmacological approaches represent promising alternatives as the traumatic nature of current therapeutic standards may lead to PTJS' progression. Losartan is an auspicious candidate, as it has demonstrated an antifibrotic effect in other organs. Forty-eight Sprague Dawley rats were randomized into equally sized losartan or control groups. After a standardized knee trauma, the joint was immobilized for either 2 weeks (n = 16), 4 weeks (n = 16) or 4 weeks with re-mobilization for an additional 4 weeks (n = 16). Pharmacotherapy with losartan or placebo (30 mg/kg/day) was initiated on the day of trauma and continued for the entire course. Joint contracture was measured alongside histological and molecular biological assessments. There were no significant biomechanical changes in joint contracture over time, comparing short-term (2 weeks) with long-term losartan therapy (4 weeks). However, comparing the formation of PTJS with that of the control, there was a trend toward improvement of joint mobility of 10.5° (p 0.09) under the influence of losartan. During the re-mobilization phase, no significant effect of losartan on range of motion (ROM) was demonstrated. At a cellular level, losartan significantly reduced myofibroblast counts by up to 72 % (4 weeks, p ≤ 0.001) without effecting the capsular configuration. Differences in expression levels of profibrotic factors (TGF-ß, CTGF, Il-6) were most pronounced at week 4. The antifibrotic properties of losartan are not prominent enough to completely prevent the development of PTJS after severe joint injury.

Is there a correlation between pelvic incidence and orientation of the acetabulum? An analysis based on a three-dimensional statistical model of the pelvic ring.

The pelvic ring is a complex anatomical structure building up the connection between the trunk and the legs. Whilst there is a broad discussion in the literature about the dynamic interaction between spine, pelvis and the hip joints, there is still little information about the relation and interaction of the constant pelvic parameters. Based on a three-dimensional (3D) statistical model consisting of 150 uninjured and bony healthy pelves (100 Europeans, 50 Japanese; 81 males, 69 females; average age 74.3 years ± 17.5 years) an evaluation of pelvic incidence (PI) and acetabular orientation in anteversion and inclination was performed and potential correlations of these intraindividual constant parameters were investigated. Pelvic incidence is defined as the angle between the perpendicular to the sacral plate at its midpoint and the line connecting this point to the middle axis of the femoral heads. Acetabular anteversion is defined as the angle between the perpendicular to the best-fit plane on the acetabular rim and the coronal plane measured in strict lateral view. Acetabular inclination is defined as the angle between the perpendicular to the best-fit plane on the acetabular rim and the sagittal plane in strict frontal view. Data were further analysed with regard to different subgroup's age, sex and ethnicity. A positive correlation between PI and acetabular anteversion could be demonstrated. Further, PI and also the acetabular parameters anteversion and inclination were found to be significantly higher in the European individuals than in the Asian. The results of the present study demonstrate a relation between the anatomical configuration of the constant pelvic parameters building up the connection points to the next proximal respectively caudal skeleton section. The findings might lead to more comprehensive treatment strategies in case of trauma or degenerative pathologies of the pelvis in the future.

Pleiotropic Long-Term Effects of Atorvastatin on Posttraumatic Joint Contracture in a Rat Model.

The antifibrotic effect of atorvastatin has already been demonstrated in several organ systems. In the present study, a rat model was used to investigate the effect of atorvastatin on posttraumatic joint contracture. Forty-eight Sprague Dawley rats were equally randomized into an atorvastatin group and a control group. After initial joint trauma, knee joints were immobilized for intervals of 2 weeks (n = 16) or 4 weeks (n = 16) or immobilized for 4 weeks with subsequent remobilization for another 4 weeks (n = 16). Starting from the day of surgery, animals received either atorvastatin or placebo daily. After euthanasia at week 2, 4 or 8, joint contracture was determined, histological examinations were performed, and gene expression was assessed. The results suggest that the joint contracture was primarily arthrogenic. Atorvastatin failed to significantly affect contracture formation and showed a reduction in myofibroblast numbers to 98 ± 58 (control: 319 ± 113, p < 0.01) and a reduction in joint capsule collagen to 60 ± 8% (control: 73 ± 9%, p < 0.05) at week 2. Gene expression of α-smooth muscle actin (α-SMA), collagen type I, transforming growth factor ß1 (TGF-ß1) and interleukin-6 (IL-6) was not significantly affected by atorvastatin. Atorvastatin decreases myofibroblast number and collagen deposition but does not result in an improvement in joint mobility.

[Minimally invasive stabilization of fragility fractures of the pelvis with transsacral bar and retrograde transpubic screw]. / Minimal-invasive Stabilisierung von Fragilitätsfrakturen des Beckens mittels transsakralem Stab und retrograder transpubischer Schraube.

OBJECTIVE: Stabilization of fragility fractures of the pelvis (FFP) using a minimally invasive technique. Insertion of a transsacral rod into the transsacral corridor of S1. Insertion of a retrograde transpubic screw through the superior branch of the pubic bone. INDICATIONS: Uni- or bilateral displaced fragility fractures of the sacrum or sacroiliac joint. Nondisplaced fractures of the sacrum or sacroiliac joint in case of nonsuccessful conservative treatment. Uni- or bilateral fractures of the superior branch of the pubic bone, which are present in combination with a posterior pelvic instability. CONTRAINDICATIONS: Fragility fractures of the pelvis, which can be successfully treated conservatively. Absence of transsacral corridor in sacral body S1. Major displacement, nonreducible fractures of the superior branch of the pubic bone. Soft tissue infection at insertion site of implants. SURGICAL TECHNIQUE: The transsacral bar is inserted under fluoroscopic control from ilium to ilium through the transsacral corridor of the sacral body S1. The retrograde transpubic screw is inserted from the pubic tubercle through the superior branch of the pubic bone past the acetabulum into the body of the ilium. POSTOPERATIVE MANAGEMENT: An early mobilization with weight bearing of both lower extremities as tolerated by the patient is allowed. Conventional radiographs for control of the position of the implants and fractures are taken after mobilization RESULTS: In all, 64 patients with FFP type II, FFP type III or FFP type IV were stabilized with a transacral bar osteosynthesis in the posterior pelvis. In 32 patients (50%), additional sacroiliac screws were inserted. In 29 patients (45.3%) the transsacral bar osteosynthesis was combined with a transpubic retrograde screw. Median length of hospital stay was 17.5 days. In all, 20 patients (31.3%) suffered general, 10 patients (15.6%) suffered surgery-related complications, and 41 patients (64.1%) were mobile in the room or on the ward at discharge. One-year mortality was 10.9%. The values of the SF­8 Physical and Mental Component Scores, Parker Mobility Score and Numeric Rating Scale were moderate, yet comparable with the values of patients of the same age.

Anatomical evaluation of the transpubic screw corridor based on a 3D statistical model of the pelvic ring.

Retrograde transpubic screw fixation is a common procedure for the treatment of anterior pelvic ring fractures. With its sparing surgical approach and significant pain relief after screw fixations allowing early mobilisation, it has gained importance especially in the treatment of insufficiency fractures in elderly patients. However, positioning of transpubic screw osteosynthesis is not always possible due to narrowness and curvature of the screw corridor. The aim of the present study was to evaluate availability and length of the screw corridor using a 3D statistical model of the pelvic ring consisting out of 150 uninjured pelves. Virtual bore probes with a diameter of 7.5 mm were analysed as to accessibility, length and grey value distribution in Hounsfield Unit (HU). A transpubic corridor with a diameter of ≥ 7.5 mm was available in 185 of 300 investigated superior pubic rami with mean screw length of 131.7 mm. Accessibility of the screw corridor was higher in males than in females. However, screw length showed no systematic differences between the sexes or ethnicities. Analysis of the grey value distribution demonstrated the strongest bone to be located at the lateral ilium and the supraacetabular region.

Dexamethasone Inhibits the Pro-Angiogenic Potential of Primary Human Myoblasts.

Tissue regeneration depends on the complex processes of angiogenesis, inflammation and wound healing. Regarding muscle tissue, glucocorticoids (GCs) inhibit pro-inflammatory signalling and angiogenesis and lead to muscle atrophy. Our hypothesis is that the synthetic GC dexamethasone (dex) impairs angiogenesis leading to muscle atrophy or inhibited muscle regeneration. Therefore, this study aims to elucidate the effect of dexamethasone on HUVECs under different conditions in mono- and co-culture with myoblasts to evaluate growth behavior and dex impact with regard to muscle atrophy and muscle regeneration. Viability assays, qPCR, immunofluorescence as well as ELISAs were performed on HUVECs, and human primary myoblasts seeded under different culture conditions. Our results show that dex had a higher impact on the tube formation when HUVECs were maintained with VEGF. Gene expression was not influenced by dex and was independent of cells growing in a 2D or 3D matrix. In co-culture CD31 expression was suppressed after incubation with dex and gene expression analysis revealed that dex enhanced expression of myogenic transcription factors, but repressed angiogenic factors. Moreover, dex inhibited the VEGF mediated pro angiogenic effect of myoblasts and inhibited expression of angiogenic inducers in the co-culture model. This is the first study describing a co-culture of human primary myoblast and HUVECs maintained under different conditions. Our results indicate that dex affects angiogenesis via inhibition of VEGF release at least in myoblasts, which could be responsible not only for the development of muscle atrophy after dex administration, but also for inhibition of muscle regeneration after vascular damage.

Trans-sacral bar osteosynthesis provides low mortality and high mobility in patients with fragility fractures of the pelvis.

Operative treatment of osteoporosis-associated fragility fractures of the pelvis (FFP) and the sacrum is advocated with immobilizing or longstanding pain, fracture progression and displacement. We analyzed clinical outcomes regarding mobility, quality of life, and mortality of patients with FFP treated with trans-sacral bar (TB) osteosynthesis through S1. Demographics, clinical data, and operation-related data of patients with an FFP treated with TB were acquired from chart review. We assessed mortality, quality of life (EQ-5D), mobility, and residential status at follow-up. Seventy-nine females and six males with a median age of 78.0 years (IQR 73-84) were included, median follow-up was 3.2 years. Medical complications during hospitalization occurred in 28%. Operative revision was carried out in 15% of patients. One-year survival was 90.4%, this was associated with shorter preoperative and total length of stay in hospital (p 0.006 and 0.025, respectively). At follow-up, 85% lived at home and 82% walked with or without walking aid. Higher EQ-5D was reached with higher mobility status and living at home (p < 0.001 and < 0.001, respectively). TB osteosynthesis is an adequate and reliable method for fixation of FFP in the posterior pelvic ring to ensure timely mobilization. Shorter preoperative and total length of stay had lower mortality rates, advocating a standardized management protocol to limit time delay to operative therapy. Patients treated with TB osteosynthesis had low 1-year mortality of less than 10%.

[Symptoms of Adjustment Disorder after an accidental injury: risk and protective factors]. / Symptome einer Anpassungsstörung nach einer Unfallverletzung: Risiko- und Schutzfaktoren.

Symptoms of Adjustment Disorder after an accidental injury: risk and protective factors Objectives: The identification of protective and risk factors for symptoms of adjustment disorder (AD) after an accident injury. Methods: In this prospective long-term study, data from 73 patients with ankle and lower leg fractures were analyzed. Symptoms of AD were assessed at enrollment (T0), 1 month (T1) and 12 months (T2) after injury. In addition, questionnaires regarding adverse childhood experiences, coping strategies and the number of stressors during the last year were obtained. The Structured Clinical Interview for DSM-IV (SCID) was conducted at T1 and T2. Results: 4.1 % of patients met the criteria for AD at T1 and 2.7 % at T2. Acceptance coping predicted a lower level of AD symptoms 1 year after the injury (ß = -.42, p <.001). Conclusions: It could be confirmed that the selection of coping strategies predicts the level of AD symptoms 12 months after the injury. The results show that acceptance is a protective factor for AD and contribute to a better understanding of a little-researched diagnosis.

Early posttraumatic stress symptoms and levels of distress in trauma patients treated in the resuscitation room: an exploratory study.

BACKGROUND: The aim of the present study was to investigate the incidence of psychological distress and posttraumatic stress symptoms in trauma patients who have been recruited from the resuscitation room. Further, we wanted to explore risk factors for posttraumatic stress symptoms, taking different accident types into account. METHODS: Our sample consisted of 45 patients who have been treated in the resuscitation room and were interviewed within the first ten days after treatment. Type of accident, third party fault, previous mental health problems and pretraumatic stress were examined. Patients were interviewed with respect to their currently felt distress regarding the accident. Posttraumatic stress symptoms were measured with the German version of the Impact of Event Scale. Injury severity was assessed by means of the Injury Severity Score. RESULTS: Our exploratory and cross-sectional project reveals that more severe injuries were associated with higher distress. However, posttraumatic stress symptoms were predicted by high distress and being involved in a car accident, but not by injury severity. CONCLUSIONS: We identified two potential risk factors for the development of posttraumatic stress in trauma patients recruited from the resuscitation room: Being involved in a car accident and high distress. TRIAL REGISTRATION: The project has been registered at the Study Center of Mental Disorders (SPE) at the University Medical Center Mainz (No: 92072014 ).

Asymmetry of the pelvic ring evaluated by CT-based 3D statistical modeling.

The human pelvis is a complex anatomical structure that consists of the innominate bones, sacrum and coccyx to form the pelvic ring. Even though considered to be a symmetric entity, asymmetry of the pelvic ring (APR) might occur to alter its anatomy, function, or biomechanics or to impact assessment and treatment of clinical cases. APR and its assessment is complicated by the intricate anatomy of the pelvic ring. There is only limited information and understanding about APR with no established evaluation methods existing. The objective of the present study was to adopt CT-based 3D statistical modeling and analysis to assess APR within the complex anatomy of the pelvic ring. We were interested to establish a better understanding of APR with knowledge and applications transferred to human anatomy, related research, and development subjects and to clinical settings. A series of 150 routine, clinical, pelvic CT protocols of European and Asian males and females (64 ± 15 (20-90) years old) were post-processed to compute gender- and ancestry-specific 3D statistical models of the pelvic ring. Evaluations comprised principal component analysis (PCA) that included size, shape, and asymmetry patterns and their variations to be assessed. Four different CT-based 3D statistical models of the entire pelvic ring were computed according to the gender and ancestry specific groups. PCA mainly displayed size and shape variations. Examination of additional PCA modes permitted six distinct asymmetry patterns to be identified. They were located at the sacrum, iliac crest, pelvic brim, pubic symphysis, inferior pubic ramus, and near to the acetabulum. Accordingly, the pelvic ring demonstrated not to be entirely symmetric. Assessment of its asymmetry proved to be a challenging task. Using CT-based 3D statistical modeling and PCA, we identified six distinct APRs that were located at different anatomical regions. These regions are more prone to APRs than other sites. Minor asymmetry patterns have to be distinguished from the distinct APRs. Side differences with regard to size, shape, and/or position require to be taken into account. APRs may be due different load mechanisms applied via spine or lower extremity or locally. There is a need for simpler and efficient, yet reliable methods to be routinely transferred to human anatomy, related research, and development subjects and to clinical settings.

Symptoms of adjustment disorder and smoking predict long-term functional outcome after ankle and lower leg fracture.

OBJECTIVE: To examine the psychological, social, behavioural and injury-related factors impacting functional outcome in patients with ankle or lower limb fracture one year post-operation. METHODS: In this prospective study 66 patients with ankle or lower leg fracture were recruited and followed up one year post-operation. Possible associations between predictors and functional outcome were explored by regression analyses. Functional outcome was assessed with the American Orthopedic Foot and Ankle Society Ankle-Hindfoot Score. RESULTS: Linear regression models revealed that smoking and elevated symptoms of adjustment disorder were associated with lower functional outcome one year post-operation. Fracture type, depressive symptoms and quality of relationship had no effect on functional outcome. A second linear regression revealed that preoccupations were correlated with functional outcome. CONCLUSION: Smoking and symptoms of adjustment disorder, specifically preoccupations, are associated with functional outcome one year post-operation in patients recovering from ankle or lower leg fractures. The results support the notion that differences in functional recovery are attributable to psychological and behavioural factors rather than to fracture type. Psychological, fracture-specific, symptoms play a role in functional recovery rather than general affective symptoms.

Detecting the Effects of the Glucocorticoid Dexamethasone on Primary Human Skeletal Muscle Cells-Differences to the Murine Cell Line.

Skeletal muscle atrophy is characterized by a decrease in muscle fiber size as a result of a decreased protein synthesis, which leads to degradation of contractile muscle fibers. It can occur after denervation and immobilization, and glucocorticoids (GCs) may also increase protein breakdown contributing to the loss of muscle mass and myofibrillar proteins. GCs are already used in vitro to induce atrophic conditions, but until now no studies with primary human skeletal muscle existed. Therefore, this study deals with the effects of the GC dexamethasone (dex) on primary human myoblasts and myotubes. After incubation with 1, 10, and 100 µM dex for 48 and 72 h, gene and protein expression analyses were performed by qPCR and Western blot. Foxo, MuRF-1, and MAFbx were significantly upregulated by dex, and there was increased gene expression of myogenic markers. However, prolonged incubation periods demonstrated no Myosin protein degradation, but an increase of MuRF-1 expression. In conclusion, applying dex did not only differently affect primary human myoblasts and myotubes, as differences were also observed when compared to murine cells. Based on our findings, studies using cell lines or animal cells should be interpreted with caution as signaling transduction and functional behavior might differ in diverse species.

Effect of bone sialoprotein coating on progression of bone formation in a femoral defect model in rats.

PURPOSE: In orthopedic and trauma surgery, calcium phosphate cement (CPC) scaffolds are widely used as substitute for autologous bone grafts. The purpose of this study was to evaluate bone formation in a femoral condyle defect model in rats after scaffold-coating with bioactive bone sialoprotein (BSP). Our hypothesis was that BSP-coating results in additional bone formation. METHODS: In 20 Wistar rats, defects of 3.0 mm diameter were drilled into the lateral femoral condyles of both legs. BSP-coated scaffolds or uncoated control scaffolds were implanted into the defects. After 4 and 8 weeks, five rats of each group were euthanized, respectively. µCT scans and histological analyses were performed. The ratio of bone volume-total volume (BV/TV) was analyzed and histological sections were evaluated. RESULTS: At week four, bone fraction reached 5.2 ± 1.7% in BSP-coated scaffolds and 4.5 ± 3.2% in the control (p = 0.06). While bone fraction of the BSP-group did not change much between week four and eight [week eight: 5.4 ± 3.8% (p = 0.53)], there was a tendency towards an increase in the control [week eight: 7.0 ± 2.2% (p = 0.08)]. No significant difference in bone fraction were observable between BSP-coated and uncoated scaffolds at week eight (p = 0.08). CONCLUSIONS: A significant superiority of BSP-coated scaffolds over uncoated scaffolds could not be proven. However, BSP-coating showed a tendency towards improving bone ingrowth in the scaffolds 4 weeks after implantation. This effect was only short-lived: bone growth in the control scaffolds tended to outpace that of the BSP-group at week eight.

Exposure to radial extracorporeal shockwaves induces muscle regeneration after muscle injury in a surgical rat model.

The leading cause of training interruption in sport is a muscle injury, for which the standard treatment is nonsteroidal anti-inflammatory drugs (NSAIDs). To find alternative treatments, we investigated whether the radial extracorporeal shockwave application (rESWT) could stimulate muscle regeneration. A lesion with complete rupture (grade III muscle tear) was set in the musculus rectus femoris of 12-week-old Wistar rats, and the NSAID diclofenac, rESWT, or a combined therapy were applied on day 0, 3, and 5 directly following the surgery. Rats were euthanized at 2, 4, and 7 days after surgery and the area of muscle lesion was excised for histological and gene expression analysis to determine the progress in the healing of damaged fibers and tissue regeneration. The best effect on muscle regeneration was observed in the group treated with rESWT alone. Monotherapy by diclofenac showed a smaller but still positive effect and lowest effects were detected when both therapies were applied. rESWT alone demonstrated a significant upregulation of the muscle markers MyoD and myosin. The presence of myosin gene expression indicated newly formed muscle fibers, which was confirmed by hematoxylin and eosin staining. Seven days after injury the amount of mononucleated cell decreased and regenerating fibers could be detected. This effect is most pronounced in the group treated with rESWT alone. In our study, shockwaves demonstrated the best effect on muscle regeneration. Therefore, we recommend prospective clinical studies to analyze the effect of rESWT after sports trauma to improve muscle regeneration and to shorten the rehabilitation.

Minimal-invasive stabilization of anterior pelvic ring fractures with retrograde transpubic screws.

BACKGROUND: In the vast majority of patients with pelvic ring lesions, there is a combination of fractures of the posterior and anterior pelvic ring. Anterior fractures are painful and contribute to loss of stability of the pelvic ring. For these reasons, stabilization of pubic rami fractures is recommended together with posterior pelvic ring fixation. Retrograde transpubic screw osteosynthesis enjoys increasing acceptance due to its minimal invasive technique and adequate stability. PATIENTS AND METHODS: We retrospectively reviewed the results of 158 retrograde transpubic screw osteosyntheses in 128 patients with pelvic ring lesions including a pubic ramus fracture. Sixty-three patients suffered a high-energy injury, 65 a fragility fracture of the pelvis. RESULTS: One hundred and forty-six screws (92.4%) were inserted through a percutaneous procedure. There were no vascular, neurological or urological complications. Fifty-nine screws (39%) yielded an excellent reduction with less than one cortical width of displacement. Slight secondary displacement was seen in 33 of these fractures (55.9%). Early surgical complications were seen in 16 screws (10.1%): suboptimal pathway in 10, local hematoma in 4 and local infection in 3. Early revision surgery was done in 7 screws (4.4%). Median follow-up was 27.6 weeks, 83 screws (52.5%) had a follow-up of more than 6 months. During follow-up, 7.6% of screws loosened. Operative revision was performed in 13%. 75 fractures (90.3%) with a follow-up of ≥ 6 months showed radiographic evidence of healing. There was no difference in the healing rate of high-energy and fragility fractures. Nonunion rate was not dependent on the quality of primary reduction, secondary displacement, or screw loosening. Infection (p 0.001) and surgery ≥ 6 months after trauma (p 0.02) more often led to nonunion. CONCLUSION: Retrograde transpubic screw osteosynthesis is a reliable method for splinting pubic rami fractures in high and low energy pelvic trauma. Although a slight secondary fracture displacement is seen in most cases, it does not affect fracture healing. Retrograde transpubic screw is a adequate minimal-invasive osteosynthesis to stabilize the anterior pelvic ring, especially in fragility fracture of the pelvis. Delayed operation (> 6 months) and infection show higher rate of nonunion.

Calf Blood Compound (CFC) and Homeopathic Drug Induce Differentiation of Primary Human Skeletal Muscle Cells.

The use of injections to treat structural muscle injuries is controversially discussed. In our controlled in vitro study, we investigated the biological impact of Actovegin and Traumeel alone and in combination on primary human skeletal muscle cells. Cells were characterized by immunofluorescence staining for myogenic factor 5 (Myf5) and MyoD, and cultured with or without Actovegin and / or Traumeel. The effects of these agents were assayed by cell viability and gene expression of the specific markers MyoD, Myf5, neural adhesion molecule (NCAM), and CD31. Myotube formation was determined by myosin staining. Neither Actovegin nor Traumeel showed toxic effects or influenced cell viability significantly. High volumes of Actovegin down-regulated gene expression of NCAM after 3 days but had no effect on MyoD, Myf5, and CD31 gene expression. High volumes of Traumeel inhibited MyoD gene expression after 3 days, whereas after 7 days MyoD expression was significantly up-regulated. The combination of both agents did not significantly influence cell viability or gene expression. This is the first study demonstrating that Actovegin and Traumeel potentially modulate human skeletal muscle cells. The relevance of these in vitro findings has to be highlighted in further in vivo studies.

Effects of losartan and atorvastatin on the development of early posttraumatic joint stiffness in a rat model.

BACKGROUND: After a trauma, exuberant tissue healing with fibrosis of the joint capsule can lead to posttraumatic joint stiffness (PTJS). Losartan and atorvastatin have both shown their antifibrotic effects in different organ systems. OBJECTIVE: The purpose of this study was the evaluation of the influence of losartan and atorvastatin on the early development of joint contracture. In addition to joint angles, the change in myofibroblast numbers and the distribution of bone sialoprotein (BSP) were assessed. STUDY DESIGN AND METHODS: In this randomized and blinded experimental study with 24 rats, losartan and atorvastatin were compared to a placebo. After an initial joint injury, rat knees were immobilized with a Kirschner wire. Rats received either losartan, atorvastatin or a placebo orally daily. After 14 days, joint angle measurements and histological assessments were performed. RESULTS: Losartan increased the length of the inferior joint capsule. Joint angle and other capsule length measurements did not reveal significant differences between both drugs and the placebo. At cellular level both losartan and atorvastatin reduced the total number of myofibroblasts (losartan: 191±77, atorvastatin: 98±58, placebo: 319±113 per counting field, p<0.01) and the percentage area of myofibroblasts (losartan: 2.8±1.8% [p<0.05], atorvastatin: 2.5±1.7% [p<0.01], vs control [6.4±4%], respectively). BSP was detectable in equivalent amounts in the joint capsules of all groups with only a trend toward a reduction of the BSP-stained area by atorvastatin. CONCLUSION: Both atorvastatin and losartan reduced the number of myofibroblasts in the posterior knee joint capsule of rat knees 2 weeks after trauma and losartan increased the length of the inferior joint capsule. However, these changes at the cellular level did not translate an increase in range of motion of the rats´ knee joints during early contracture development.

Space available for trans-sacral implants to treat fractures of the pelvis assessed by virtual implant positioning.

INTRODUCTION: The use of trans-sacral implants to treat fractures of the sacrum is limited by the variable pelvic anatomy. We were interested in how many trans-sacral implants can be placed per pelvis? If a trans-sacral implant cannot be placed in S1, where is the cortex perforated, and is the use of sacroiliac screws safe in these pelves? MATERIALS AND METHODS: 3D pelvic models were created from CT scans of 156 individuals without fractures (92 European and 64 Japanese, 79 male and 77 female, mean age 66.7 ± 13.7 years). Trans-sacral implants with a diameter of 7.3 mm were positioned virtually with and without a surrounding safe zone of 12 mm diameter. RESULTS: Fifty-one percent of pelves accommodated trans-sacral implants in S1 with a safe zone. Twenty-two percent did not offer enough space in S1 for an implant even when ignoring the safe zone. Every pelvis had sufficient space for a trans-sacral implant in S2, in 78% including a safe zone as well. In S1, implant perforation was observed in the sacral ala and iliac fossa in 69%, isolated iliac fossa perforation in 23% and perforation of the sacral ala in 8%. Bilateral sacroiliac screw placement was always possible in S1. CONCLUSIONS: The use of trans-sacral implants in S1 requires meticulous preoperative planning to avoid injury of neurovascular structures. S2 more consistently offers space for trans-sacral implants.