[Retroperitoneal lipoblastoma in an infant. A case report]. / Lipoblastoma retroperitoneal en un lactante. Caso clínico.

INTRODUCTION: Lipoblastoma is a benign neoplasia of the adipose tissue. It is a rare conditionand almost exclusively presents in children under 3 years old. It usually occurs in extremities as a painless volume increase of progressive growth, with the definitive diagnosis being established by pathological and cytogenetic analysis. The treatment of choice is complete resection, and follow-up period of up to five years is recommended due to a recurrence of up to 25%. OBJECTIVE: To present an unusual location of this uncommon condition in an infant, and review the related literature. CASE REPORT: A sixteen-month child with an increase in abdominal growth of six-months progression, associated with a decreased food intake, and with no other symptoms. The imaging study revealed a lipoid-like image compromising almost the entire abdominal cavity, very suggestive of lipoblastoma. A resection was performed on an 18cm diameter retroperitoneal tumour that rejected the adjacent organs. Histological analysis was enough to confirm diagnosis without the need for cytogenetic analysis. The follow-up showed no recurrence of the disease. CONCLUSION: Given the rarity of this disease and its unusual presentation, we communicate this clinical case, in order to be considered in the differential diagnosis of abdominal mass in chilhood.

Intracellular proliferation of S. aureus in osteoblasts and effects of rifampicin and gentamicin on S. aureus intracellular proliferation and survival.

Staphylococcus aureus is the most clinically relevant pathogen regarding implant-associated bone infection and its capability to invade osteoblasts is well known. The aim of this study was to investigate firstly whether S. aureus is not only able to invade but also to proliferate within osteoblasts, secondly to delineate the mechanism of invasion and thirdly to clarify whether rifampicin or gentamicin can inhibit intracellular proliferation and survival of S. aureus. The SAOS-2 osteoblast-like cell line and human primary osteoblasts were infected with S. aureus EDCC5055 and S. aureus Rosenbach 1884. Both S. aureus strains were able to invade efficiently and to proliferate within human osteoblasts. Immunofluorescence microscopy showed intracellular invasion of S. aureus and transmission electron microscopy images could demonstrate bacterial division as a sign of intracellular proliferation as well as cytosolic bacterial persistence. Cytochalasin D, the major actin depolymerisation agent, was able to significantly reduce S. aureus invasion, suggesting that invasion was enabled by promoting actin rearrangement at the cell surface. 7.5 µg/mL of rifampicin was able to inhibit bacterial survival in SAOS-2 cells with almost complete elimination of bacteria after 4 h. Gentamicin could also kill intracellular S. aureus in a dose-dependent manner, an effect that was significantly lower than that observed using rifampicin. In conclusion, S. aureus is not only able to invade but also to proliferate in osteoblasts. Invasion seems to be associated with actin rearrangement at the cell surface. Rifampicin is effective in intracellular eradication of S. aureus whereas gentamicin only poorly eliminates intracellularly replicating bacteria.

Cholinergic nerve fibers in bone defects of a rat osteoporosis model and their regulation by implantation of bone substitution materials.

OBJECTIVES: Bone is innervated by autonomic nervous system that consists of sympathetic and parasympathetic nerves that were recently identified in bone. Thus we asked whether parasympathetic nerves occur in bone defects and at the interface of substitution materials that were implanted for stabilization and improvement of healing in an osteoporosis animal model. METHODS: Osteoporosis was induced in rats by ovariectomy and deficiency diet. A wedge-shaped osteotomy was performed in the metaphyseal area of femur. Eight different implants were inserted that were based on calcium phosphate cement, iron, silica-mineralized collagen, and modifications with strontium. Nerves were identified by immunohistochemistry with antibodies against vesicular acetylcholine transporter (VAChT), tyrosine hydroxylase (TH) and protein gene product 9.5 (PGP 9.5) as neuronal marker. RESULTS: Cholinergic nerves identified with VAChT immunostaining were detected in defects filled with granulation tissue and in surrounding mast cells. No immunolabeling of cholinergic nerves was found after implantation. The general presence of nerves was reduced after implantation as shown by PGP 9.5. Sympathetic nerves identified by TH immunolabeling were increased in strontium functionalized materials. CONCLUSION: Since cholinergic innervation was diminished after implantation a further increase in the compatibility of substitution materials to nerves could improve defect healing especially in osteoporotic bone.

Short-term glucocorticoid treatment causes spinal osteoporosis in ovariectomized rats.

PURPOSE: In humans, glucocorticoid-induced osteoporosis is the most common cause of medication-induced osteoporosis. Recent clinical data suggest that glucocorticoid therapy increases the risk of vertebral fractures within a short treatment period. Therefore, this study aimed at investigating vertebral bone in a rat model of glucocorticoid-induced postmenopausal osteoporosis. METHODS: Fifty Sprague-Dawley rats were randomly assigned into three groups: 1) untreated controls, 2) Sham-operated group, and 3) ovariectomized rats treated with glucocorticoid (dexamethasone) for 3 months (3M) after recovery from bilateral ovariectomy. Osteoporotic bone status was determined by means of the gold standard dual energy X-ray absorptiometry (DEXA) scan. Vertebral bodies were examined using µCT, histological analysis, mRNA expression analysis, and biomechanical compression testing. Further systemic effects were studied biochemically using serum marker analysis. RESULTS: Dexamethasone treatment showed at 3M a significantly lower bone mineral density in ovariectomized rats compared to Sham-operated control (p < 0.0001) as analyzed in vivo by DEXA. Furthermore, Z scores reached levels of -5.7 in the spine indicating sever osteoporotic bone status. Biomechanical testing of compression stability indicated a lower functional competence (p < 0.0001) in the spine of treated rats. µCT analysis showed significant reduction of bone volume density (BV/TV%; p < 0.0001), significantly enhanced trabecular spacing (Tb.Sp; p < 0.0001) with less trabecular number (Tb.N; p < 0.001) and complete loss of trabecular structures in glucocorticoid-treated ovariectomized rats. Histological analysis by osteoblast and osteoclast activities reflected a higher bone catabolism reflected by osteoclast counts by TRAP (p < 0.019) and lower bone catabolism indicated by ALP-stained area (p < 0.035).Serum analysis showed a significant increase in osteocalcin (p < 0.0001), osteopontin (p < 0.01) and insulin (p < 0.001) at 3M. Expression analysis of molecular markers in the vertebral body revealed lower expression in tenascin C in the OVX-steroid animals at 3M. CONCLUSIONS: Short-term glucocorticoid treatment of ovariectomized rats indicates according to DEXA standards a severe osteoporotic bone status in vertebral bone. Nonetheless, dysfunctional bone anabolism and enhanced bone catabolism are observed. Alterations of bone extracellular matrix proteins that correlate to inferior mechanical stability and affected microstructure were noticed and suggest further investigation. Treatment with dexamethasone was also seen to affect insulin and osteopontin levels and thus osteoblast function and maturation. This described animal model presents a recapitulation of clinically obtained data from early phase glucocorticoid-induced osteoporosis observed in patients.

[Fractures of the thoracic and lumbar spine in children and adolescents]. / Frakturen der Brust- und Lendenwirbelsäule im Wachstumsalter.

BACKGROUND: Only 1.5-2% of all fractures in children and adolescents are fractures of the thoracic and lumbar spine. Treatment is most often conservative. This study compares the own experience with the recent literature. MATERIAL AND METHODS: Over a 48 month period all patients with fractures of the thoracic and lumbar spine, younger than 16 years were included prospectively. Of the patients 67 underwent follow-up investigations after 3-36 months. RESULTS: The average age of the patients was 11.9 years. Sports (53%) and traffic (28%) accidents were most frequent. Fractures most often appeared in the mid-thoracic (47%) and thoracolumbar spine (41%). Operative treatment was performed in 9 cases (10.4%). Secondary loss of alignment was not observed neither after conservative nor operative treatment. Neurological deficits (n=2) did not completely improve. CONCLUSIONS: Most fractures of the thoracic and lumbar spine heal fast and without any sequelae. Unstable fractures of type B and C (exclusively occurring as a result of traffic accidents) need operative stabilization as in adults.

[Operative treatment of rhizarthritis: comparison of ligament reconstruction according to Epping with trapezectomy and interposition of pyrocarbon spacers as replacement of the trapezium]. / Operative Versorgung der Rhizarthrose: Vergleich der Resektionssuspensionsarthroplastik mit der Trapezektomie und Interposition eines Pyrocarbonspacers als Trapeziumersatz.

BACKGROUND: Rhizarthritis is the most common form of arthritis of the hand with a frequency of 10% and conservative as well as surgical methods of treatment are available. The aim of this study was to compare the results of resection suspension arthroplasty according to Epping with trapezium replacement using pyrocarbon spacers. MATERIAL AND METHODS: Between January 2001 and December 2008 a total of 84 patients were surgically treated for rhizarthritis in our clinic. Of these patients 12 were treated with other surgical procedures, 40 with resection suspension arthroplasty according to Epping and 32 with pyrocarbon spacers as trapezium replacement. The patients were examined in a retrospective study and success of treatment was evaluated according to the Buck-Gramcko criteria. RESULTS: According to the evaluation criteria over 80% of patients in both collectives achieved very good or good operative results with the same degree of satisfaction. CONCLUSION: The results of this study confirm the value of resection suspension arthroplasty according to Epping for surgical treatment of rhizarthritis. Using trapezectomy with interposition of pyrocarbon spacers good or very good results can be achieved in the majority of cases. Essential points of criticism are the current material cost of 930 Euros and 4 dislocations in our collective but with good multiaxial movement and loading capacity. Comparable results using alternative procedures indicate that the results of further studies and long-term results will be decisive for establishment of this operational procedure.

[Traumatic physeal separations of the distal tibia. Occurrence, forms, treatment strategies]. / Traumatische Wachstumsfugenlösungen der distalen Tibia. Aufkommen, Formen, Behandlungsstrategien.

Traumatic physeal separations (SH I/II) of the lower extremities are rare. Complications are reported in 2.2-39.6%. The current study is intended to provide recent data concerning epidemiology and treatment decisions in physeal separation of the distal tibia. All patients who suffered a physeal separation of the distal tibia in a 36-month period were included in a multicenter study. Age, gender, mechanism of injury, classification, therapeutic decision, and early complications were recorded online. There were 150 cases (64.6% male, 35.4% female, average age 11.8 years). The most frequent mechanism of injury was sportive activity (42%); 76% of cases needed reduction. Antecurvation was tolerated up to 10° (p=0.0021) and valgus up to 7° (p=0.0155). Tolerance ranges up to 5° of retrocurvation and varus were not statistically significant. The investigation confirmed epidemiological data of former studies. For the first time data concerning the treatment reality of physeal separations of the distal tibia were recorded. They consistently follow the recommendations of the appropriate literature.

[Intramedullary nailing of periprosthetic femoral fractures after revision for total knee endoprosthesis. Treatment of periprosthetic femoral fractures by inserted knee endoprostheis with intramedullary shaft by in situ lengthening of the prosthesis with specially prepared slotted hollow nails]. / Marknagelung periprothetischer Femurfrakturen nach Revisions-Knietotalendoprothese. Behandlung periprothetischer Femurfrakturen bei einliegender Knieendoprothese mit intramedullärem Stiel durch In-situ-Verlängerung der Prothese mit einem sonderangefertigten geschlitzten Hohlnagel.

BACKGROUND: With the increasing number of revision operations after knee replacement a growing incidence of periprosthetic femoral fractures which are difficult to treat is observed. MATERIAL AND METHODS: This retrospective study describes the operating procedure for osteosynthetic treatment of periprosthetic femoral fractures using a specially made slotted hollow nail which is engrafted with the purpose of in-situ lengthening of the prosthesis and thus becomes stably clamped. From 1999 to 2008 our patients have included 9 who were treated by this method. There were 5 male and 4 female patients with an average age of 63.4 years (range 47­80 years). Prerequisites for the performance of this operation are stability of the prosthesis and knowledge of the type of prosthesis or exact preoperative planning based on CT measurement of the thickness and length relationships. RESULTS: It was possible to conduct a clinical and radiological follow-up examination of all 9 patients after an average time of 29.1 months (range 10­64 months). In all cases load-bearing stabilization of the fracture was confirmed. CONCLUSION: In-situ coupling of an endoprosthesis with a slotted hollow nail represents a valuable treatment option for periprosthetic fractures.

[Do paediatric and adult surgeons follow different approaches to physeal fractures?]. / Haben Kinderchirurgen und Erwachsenenchirurgen unterschiedliche Therapieansätze bei der Behandlung von Wachstumsfugenlösungen?

INTRODUCTION: The treatment of paediatric fractures is the concern of several different surgical specialties. There has been no scientific investigation on the different concepts of paediatric (PS) and adult surgeons (AS). METHODS: 62 paediatric traumatologists were asked concerning their experience with physeal fractures of the leg, including ten cases. RESULTS: Growth disturbances was estimated to be more rare by PS. On evaluation of the examples there were no significant differences in the judgement of degree and direction of the displacement. For displaced fractures, PS rather preferred closed reduction and immobilisation, whereas AS favoured osteosynthesis. DISCUSSION: There were no basic differences between PS and AS in the treatment of lower limb fractures. AS tend to act more invasively. At the same time they are more concerned about growth disturbances.

[Minimally invasive management of Choledochal Cyst in pediatric age]. / Manejo mínimamente invasivo de Quiste de Colédoco en edad pediátrica.

INTRODUCTION: The choledochal cyst (also bile duct cyst) is a rare condition. It is important to know its clinical presentation, diagnosis, and treatment alternatives, which allow a resolution with low morbidity. OBJECTIVE: to report the clinical diagnosis together with the laparoscopic techniques for the mana gement of the bile duct cyst. CLINICAL CASES: Case 1: 4-year-old preschooler with history of recurrent abdominal pain. Abdominal ultrasound showed a choledochal cyst. Blood amylase levels 111 IU / L. Other tests were normal. Case 2: 5-year-old preschooler with a 5-days history of abdominal pain, vomiting, and diarrhea. He was admitted due to acute pancreatitis (blood lipase 947 IU / L, blood amylase 217 IU / L). Abdominal CT scan reported a lobulated cystic lesion in the hilum of the liver. Case 3: 3-year-old preschooler with recurrent abdominal pain and a 3-day history of epigastric pain and vomiting. Blood amylase and lipase levels were 248 IU / L and 253 IU / L, respectively, diagnosing acute pancreatitis. Abdominal CT scan showed a finding suggestive of a common bile duct cyst. In all 3 cases, the magnetic resonance cholangiopancreatography reported a type I choledochal cyst. All pa tients underwent laparoscopic surgery, performing cyst resection, and hepaticoduodenostomy. One case presented pneumobilia without requiring specific management, the other two did not present incidents and all remain asymptomatic in the follow-up period that was longer than one year after surgery. CONCLUSIONS: In the choledochal cyst, clinical suspicion and timely diagnosis with imaging studies and minimally invasive surgery are important, which allow optimal results in the medium- and long term.

[Acute compartment syndrome of the lower leg as an interdisciplinary complication after long duration intervention in the lithotomy position]. / Das lagerungsbedingte Kompartmentsyndrom des Unterschenkels als Komplikation nach Eingriffen in Steinschnitt-Position.

INTRODUCTION: The positioning-related compartment syndrome of the lower leg after long-duration operations in the lithotomy position -represents a rare complication. The aim of this retrospective study was to draft recommendations to avoid this rare complication by reviewing the cases with positioning-related compartment syndromes in our own patient data. PATIENTS / MATERIAL AND METHODS: From January 1996 to February 2009, 3 women and 1 man with an average age of 38 years (24 to 55 years) were treated with a medial and lateral dermatofasciotomy with opening of lower leg loges due to a clinically manifested compartment syndrome of the -lower leg after long-duration operations in the -lithotomy position. RESULTS: In all 4 patients a dermatofasciotomy with opening of the lower leg compartments could -avoid considerable secondary damage of the limb. A long-duration lithotomy position in connection with obesity, a low positioning of the head as well as nicotine abuse are only some of the risk factors contributing to the development of a positioning-related compartment syndrome. An epidural anaesthesia bears the risk of a protracted diagnosis. CONCLUSION: The positioning-related compartment syndrome represents a rare but considerable complication after long-duration operations in the -lithotomy position. It is a clinical complication and the inducing and exponentiation risk factors as well as the clinical symptoms should be known by the treating team. If the operation time is expected to be longer than 3 hours, we recommend written information to the patient concerning this complication. Consequent postoperative controls of risk patients are obligatory. An epidural anaesthesia bears the risk of a protracted diagnosis. In the case of suspected compartment syndrome we recommend early dermatofasciotomy in order to avoid -irreversible damage to the limb.

Enhanced alpha 1(I) mRNA expression in frozen shoulder and dupuytren tissue.

The purpose of this study has been to investigate collagen I and III synthesis during the fibrosing stage of frozen shoulder and Dupuytren samples in comparison to normal capsule tissue. - By using the quantitative PCR significantly increased levels of alpha 1(I) mRNA transcription in samples of frozen shoulder (p = 0.016) and Duypuytren (p = 0.041) could be demonstrated, whereas alpha 2(I) and alpha 1(III) chains have shown the same mRNA levels as in normal capsule tissue. - Despite an enhancement of alpha 1(I) mRNA transcription in frozen shoulder and Dupuytren samples the intracellular precursor procollagen I and extracellular mature collagen I was detected immunohistochemically in reduced levels. - The structural alteration of collagen I assembly might be caused by disturbed post-translation from the polypeptide chains into the triple helices procollagen I though alpha 1(I) mRNA transcription was significantly increased and alpha 2(I) mRNA transcription was in normal range. Fibroblasts might release high quantities of free alpha 1(I) polypeptide chains or (alpha 1(I)) 3 homotrimer into the extracellular space during the fibrosing stage of frozen shoulder and Dupuytren disease. - In all samples neither differences of alpha 1(III) mRNA transcription nor differences of immunohistochemical staining intensity of collagen III could be seen. This might result from apoptosis of myofibroblasts in the final phase of the fibrosing processes. - The stimulating effect of insulin-like growth factor type I (IGF-I) to induce fibrosis in connective tissue such as scarlet is known. In all patients suffering from frozen shoulder and Dupuytren disease the serum IGF-I level was in a normal range and the IGF-I receptor - (IGFR-I) mRNA transcription in the samples was also in the same level compared with normal capsule tissue.

[Distal radius fracture - a goalkeepers' injury in children and adolescents]. / Die Distale Radiusfraktur - eine Torwartverletzung bei Kindern und Jugendlichen.

INTRODUCTION: Fractures of the distal radius are the most frequent fractures of longbones during childhood and adolescence. A rare mechanism of injury is the attempt of a soccer goalkeeper to save the ball, shot with high velocity. MATERIAL AND METHODS: Reports of all children and adolescents up to the age of 14, suffering from a distal radius fracture from a three year period were evaluated retrospectively and this particular mechanism of injury was identified. All patients were reinvestigated after at least 10 months clinically. RESULTS: Amongst 516 distal radius- and distal forearm fractures, there were 213 (41.3 %) sports injuries. 61(28.6 %) of them resulted from playing soccer, with 48 (78.7 %) after a fall. 13 distal radius fractures were identified as a goalkeepers injury by a sharply shot ball. We found 6 buckle fractures, 4 complete fractures, 2 physeal separations Salter II and 1 metaphyseal greenstick fracture. At the time of the last follow up investigation all injured had regained their level of sports. DISCUSSION: Injuries to the lower extremities are most frequent in soccer. The ball itself may lead to fractures and dislocations of the hand and finger skeleton, even not unfrequently to distal radius fractures. Wrist protectors and an adequate behaviour in game and training may contribute to their avoidance.

[Distraction osteogenesis for adjusting humeral length difference due to premature closure of the proximal growth plate in a simple bone cyst]. / Vorzeitiger Verschluss der proximalen Oberarmwachstumsfuge bei juveniler Knochenzyste. Armlängenausgleich durch Kallusdistraktion.

Complications after pathological fractures of simple bone cysts of the humerus are refracture, cyst recurrence, and in rare cases premature closure of the physeal plate with resulting shortening of the arm. Length discrepancies of the lower limbs beyond physiological limits need early compensation in children as well as adults to avoid interference with the pelvis and spine. However, surgical treatment of length differences of the humerus is usually cosmetic, because even considerable discrepancies do not lead to functional deficits. We report the long-term course of a complicated bone cyst of the proximal humerus and resolving a severe length difference of 7 cm by distraction osteogenesis in a young adult. The cause of the premature physeal closure and the primary therapeutical concept are discussed.

Suprapatellar nailing of tibial fractures-Indications and technique.

Intramedullary nailing is the standard procedure for surgical treatment of closed and Gustilo-Anderson Grade I-II° open fractures of the tibial shaft. The use of intramedullary nailing for the treatment of proximal metaphyseal tibia fractures is frequently followed by postoperative malalignment, whereas plate osteosynthesis is associated with higher rates of postoperative infection. Intramedullary nailing of tibial fractures is generally performed through an infrapatellar approach. The injured extremity must be positioned at a minimum of 90° of flexion in the knee joint to achieve optimal exposure of the correct entry point. The tension of the quadriceps tendon causes a typical apex anterior angulation of the proximal fragment. The suprapatellar approach improves reduction of the fracture and reduces the occurrence of malalignment during intramedullary nailing of extra-articular proximal tibial fractures. The knee is positioned in 20° of flexion to neutralise traction forces secondary to the quadriceps muscle, thus preventing an apex anterior angulation of the proximal fragment. An additional advantage of the technique is that it allows the surgeon to avoid or minimise further soft tissue damage because of the distance between the optimal incision point and the usual area of soft tissue damage.

Fixation performance of an ultrasonically fused, bioresorbable osteosynthesis implant: A biomechanical and biocompatibility study.

Bioresorbable implants may serve as an alternative option for the fixation of bone fractures. Because of their minor inherent mechanical properties and insufficient anchorage within bone bioresorbable implants have so far been limited to mechanically nondemanding fracture types. By briefly liquefying the surface of the biomaterial during insertion, bioresorbable implants can be ultrasonically fused with bone to improve their mechanical fixation. The objective of this study was to investigate the biomechanical fixation performance and in vivo biocompatibility of an ultrasonically fused bioresorbable polymeric pin (SonicPin). First, we biomechanically compared the fused pin with press fitted metallic and bioresorbable polymeric implants for quasi-static and fatigue strength under shear and tensile loading in a polyurethane foam model. Second, fused implants were inserted into cancellous bovine bone and tested biomechanically to verify the reproducibility of their fusion behavior. Finally, the fused pins were tested in a lapine model of femoral condyle osteotomies and were histologically examined by light and transmission electron microscopy. While comparable under static shear loads, fixation performance of ultrasonically fused pins was significantly (p = 0.001) stronger under tensile loading than press fit implants and showed no pull-out. Both bioresorbable implants withstood comparable fatigue shear strength, but less than the K-wire. In bovine bone the ultrasonic fusion process worked highly reproducible and provided consistent mechanical fixation. In vivo, the polymeric pin produced no notable foreign body reactions or resorption layers. Ultrasonic fusion of polymeric pins achieved adequate and consistent mechanical fixation with high reproducibility and exhibits good short-term resorption and biocompatibility.

Plasma transglutaminase factor XIII induces microvessel ingrowth into biodegradable hydroxyapatite implants in rats.

Coagulation factor XIII is a member of the transglutaminase-family. Transgluaminases cross-link either fibrin monomers in blood coagulation or extracellular proteins in extracellular matrix formation. In early stages of bone healing migration and proliferation of endothelial cells lead to formation of new vessels. The aim of this study was to investigate the angiogenetic activity of plasma factor XIII in bone defects filled with nanoparticulate hydroxyapatite paste. A critical size defect was created in the tibial head of rats which was not filled in group I. In group II the defect was filled with hydroxyapatite paste, and in group III with hydroxyapatite paste enriched with factor XIII. Ten days after surgery angiogenesis in the defects was assessed using immunohistochemistry and confocal laser scanning microscopy. Ac16 antibody was used to detect activation of factor XIII into factor XIIIA. In defects without biomaterial (group I) vessel-rich connective tissue and diffuse distribution of capillaries was observed. In defects filled with pure hydroxyapatite (group II) formation of capillaries was limited to the host bone-hydroxyapatite interface. In contrast, addition of plasma factor XIII to hydroxyapatite (group III) stimulated formation of vessels within the biomaterial. The current study reveals that factor XIII can improve angiogenesis in hydroxyapatite.

[Allocating and scheduling operating room time]. / Zuweisung und Planung von Operationsraumkapazitäten Maximierung der Operationsraumeffizienz am Beispiel einer deutschen Universitätsklinik.

During the past decade many scientific advances have been made concerning the development of methodologies to maximize efficiency of surgical facilities through allocating and scheduling of operating rooms. In this article such a methodology is described. Using the analysis of historical data of surgical activity in a facility, future demand is predicted and planned. Part of the methodology includes principles and rules needed for the daily organization and operative management of surgical facilities. They are also derived from the same science and therefore the basis for rational and structured decision making. Medical aspects such as patient safety and free choice of day for surgery have higher priority than the economic goal of maximizing operating room efficiency.

[Fractures of the scaphoid tubercle]. / Die Frakturen des Tuberculum ossis scaphoidei.

BACKGROUND: Avulsion fractures of the scaphoid tubercle (Herbert type A1) are rare. Recommendations in the literature focus on a four to six week plaster immobilization including the thumb. Surgery is recommended in case of additional injuries to the carpus. MATERIAL AND METHODS: In a retrospective investigation including a 36 month period we reviewed acute fractures of the scaphoid and avulsion fractures of the scaphoid tubercle. RESULTS: We found 81 acute scaphoid fractures, four of them (4.9 %) were isolated tuberculum avulsions. Three cases were extra-, one case an intraarticular fracture. The first were treated conservatively, the last with a percutaneous screw. CONCLUSIONS: Following our own experiences with those rare injuries we recommend a differentiation of the fracture type into extraarticular injuries where conservative treatment should still be performed and intraarticular fractures where percutaneous screw osteosynthesis should be discussed.

[Micro-CT analysis of cancellous bone fragments from the distal radius fracture zone in osteoporosis]. / Mikro-CT Analyse spongiöser Fragmente aus der distalen Radiusfrakturzone bei Osteoporose.

The incidence and prevalence of osteoporosis must be considered to continue to increase significantly due to the expected demographic development and environmental changes. In the diagnosis and staging of osteoporosis the three-dimensional bone structure should be as important as the bone mass or the mineral content of the bone. In this study, microfragments were taken from distal radius fracture zones and investigated in Micro-CT scans. Patients in which osteodensitometry of the lumbal spine had revealed osteoporosis in were found to have significantly reduced bone mass, bone density and trabecular thickness. Trabecular fractures which were found in non-osteoporotic patients even in robust trabeculae were detected by the two-dimensional analysis in thin locations and arborizations. Despite some trabeculae turned out to be very small the differences in the histomorphometry and the quality of trabecular fractures in osteoporotic as well as non-osteoporotic patients could be visualized very good in the Micro-CT analysis.