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The pelvic coordinate system (CS) plays an important role in total hip replacement (THR). It is defined by the mid-sagittal plane (MSP) and the so-called anterior pelvic plane (APP) comprising the anterior superior iliac spines (ASISs) and the pubic tubercles (PTs).

The most essential improvement of modern hip resurfacing arthroplasty is the metal-on-metal bearing as well as the integration of a procedure for the exact and repeatable positioning of the femoral component through a specific mechanical alignment instrument. Nevertheless, the main reasons for early implant failure are mal-positioning of the femoral component and notching of the femoral neck during femoral head preparation.In the context of an in vitro study, in each case six DUROM-Hip resurfacing prostheses were implanted in artificial femora with the prosthesis-specific mechanical alignment instrument, as well as under navigation control. The aim of the study was to evaluate the functionality and accuracy of a computer-assisted planning and navigation system on the basis of a navigation module library from Surgitaix AG (Aachen, Germany), as well as a comparison with the prosthesis-specific mechanical alignment instrument.The main angulation error between planning and navigation of the stem-shaft angle was 0.2+/-1.2 degrees for the navigation system and 6.5+/-4.1 degrees for the mechanical alignment instrument, the main anterior offset error was 1.2+/-1.2 mm vs. -0.83+/-4.1 mm. The mean time for all five planning and navigation steps was 17+/-1.2 min vs. 14+/-0.8 min. The main distance error between planning and navigation was 1.9+/-0.6 mm for the navigation system, and 5.3+/-2.4 mm for the mechanical alignment instrument. Femoral notching was not observed for navigational or conventional positioning.The computer-assisted fluoroscopic planning and navigation system for hip resurfacing showed, within the scope of this in vitro study, first promising experiences. The system approves a practicable planning with a high accuracy in implementation. Nevertheless, the potential benefit has to be evaluated in further clinical studies, especially from the perspective of a possible integration of this navigation system into the clinical workflow. Further studies should consider a fluoroscopy-assisted range of motion assessment under consideration of an additional cup-module to enhance the postoperative range of motion after hip resurfacing procedures.

Background The current surgical therapy of midfacial fractures involves internal fixation in which bone fragments are fixed in their anatomical positions with osteosynthesis plates and corresponding screws until bone healing is complete. This often causes new fractures to fragile bones while drilling pilot holes or trying to insert screws. The adhesive fixation of osteosynthesis plates using PMMA bone cement could offer a viable alternative for fixing the plates without screws. In order to achieve the adhesive bonding of bone cement to cortical bone in the viscerocranium, an amphiphilic bone bonding agent was created, analogous to the dentin bonding agents currently on the market. Methods The adhesive bonding strengths were measured using tension tests. For this, metal plates with 2.0 mm diameter screw holes were cemented with PMMA bone cement to cortical bovine bone samples from the femur diaphysis. The bone was conditioned with an amphiphilic bone bonding agent prior to cementing. The samples were stored for 1 to 42 days at 37 degrees C, either moist or completely submerged in an isotonic NaCl-solution, and then subjected to the tension tests. Results Without the bone bonding agent, the bonding strength was close to zero (0.2 MPa). Primary stability with bone bonding agent is considered to be at ca. 8 MPa. Moist storage over 42 days resulted in decreased adhesion forces of ca. 6 MPa. Wet storage resulted in relatively constant bonding strengths of ca. 8 MPa. Conclusion A new amphiphilic bone bonding agent was developed, which builds an optimizied interlayer between the hydrophilic bone surface and the hydrophobic PMMA bone cement and thus leads to adhesive bonding between them. Our in vitro investigations demonstrated the adhesive bonding of PMMA bone cement to cortical bone, which was also stable against hydrolysis. The newly developed adhesive fixing technique could be applied clinically when the fixation of osteosynthesis plates with screws is impossible. With the detected adhesion forces of ca. 6 to 8 MPa, it is assumed that the adhesive fixation system is able to secure bone fragments from the non-load bearing midfacial regions in their orthotopic positions until fracture consolidation is complete.

Purpose In the treatment of midface fractures, the fragments are immobilized using screws and plates for osteosynthesis until reunion has occurred. This method involves drilling holes for the insertion of the screws, which can be associated with additional fracturing of the corresponding bone owing to the complex architecture and thin layers of facial bone. To alleviate this problem, new adhesive techniques for fixing the plates for osteosynthesis have been investigated, mitigating the detrimental effects of screw hole drilling. In the present experimental study, the strength of this adhesive bond and its resistance to hydrolysis were investigated. Materials and Methods To determine the adhesive bonding strength, a tension test was implemented. Osteosynthesis plates with screw holes 1.3 mm in diameter were fixed to cortical bone samples of bovine femur using ultraviolet (UV) light-curing polymethylmethacrylate bone cement. To facilitate bonding, the surface of the bone was conditioned with an amphiphilic bonding agent before cementing. UV light curing was implemented using either a conventional UV unit, such as is used in dentistry, or with a specialized UV unit with a limited emission spectrum but high luminosity. Reference control samples were prepared without application of the bone bonding agent. After this procedure, the samples were stored for 1 to 7 days at 37°C submerged in 0.9% saline solution before being subjected to the tension test. Results Without the bone bonding agent, the bonding strength was 0.2 MPa. The primary average bonding strength at day 0 was 8.5 MPa when cured with the conventional UV unit and 14 MPa for the samples cured with the specialized UV unit. An almost constant average bond strength of 8 and 16 MPa was noted for all samples stored up to 7 days after curing with the conventional and specialized UV unit, respectively. Conclusion With the development of a new bone bonding agent, a method is now available to promote the bonding between the hydrophilic bone surface and the hydrophobic polymethylmethacrylate bone cement by creating an interlayer that is beneficial for adhesion. In the present in vitro study, the strength of this bond and its resistance to hydrolysis were investigated. This new method could have clinical bearing in cases in which conventional fixation with screws and plates is limited, such as can occur in comminuted fractures. The observed average bonding strengths of 8 to 16 MPa support the implementation of this technique in nonload-bearing regions such as the midface, facilitating immobilization until the bone reunion is complete.

Die Anzahl an notwendigen Revisions-und Wechseloperationen nach Hufttotalendoprothesen steigt kontinuierlich (◘ Abb. 4.1) [1, 2]. Nicht verhindern lasst sich der damit verbundene Knochenverlust im Azetabulum und am Femur [3]. Die Wiederherstellung von anatomisch knochernen Verhaltnissen und biomechanisch korrekter Implantatlage ist eine grose Herausforderung, die auf unterschiedliche Weise angegangen werden kann. Fur die Revision des Azetabulums wurden z. B. grose zementfreie Pfannen (sog. Jumbo-Pfannen), Revisionsringe, Stutzschalen und schlussendlich auch Keramiktransplantate verwendet. Diese Methoden stellen zwar die Biomechanik wieder her, fuhren aber nicht zum Wiederherstellen des Knochenlagers. Andere Methoden, wie z. B. Medialisierung der Pfanne oder Implantation in einem hoheren Huftzentrum, konfigurieren eine Situation, die nicht der normalen Biomechanik entspricht. Alternativ konnen Knochendefekte durch modulare porose Metallaugmentationen uberbruckt werden. Als Hauptziel bei der Hufttotalendoprothesenrevisionsoperation sollte neben dem Wiederherstellen der biomechanischen Physiologie immer auch die Wiederherstellung des Knochenlagers im Vordergrund stehen, um im Falle einer weiteren Revision wieder anatomische knocherne Verhaltnisse vorzufinden, die eine neuerliche Implantation ermoglichen. Dieses Kapitel behandelt den Einsatz von Allografts aus der Knochenbank zum Erreichen dieses Ziels.

Cemented femoral stems have shown decreased longevity compared to cementless implants in hip revision arthroplasty. The aim of this study was to evaluate the effect of an amphiphilic bonder on bone cement stability in a biomechanical femur expulsion test. A simplified hip simulator test setup with idealised femur stem specimens was carried out. The stems were implanted into bovine femurs (group 1: no bonder, n=10; group 2: bonder including glutaraldehyde, n=10; group 3: bonder without glutaraldehyde, n=10). A dynamic loading (maximum load: 800 N; minimum load: 100 N; frequency: 3 Hz; 105 cycles) was performed. Subsequently, the stem specimens were expulsed axially out of their implant beds and maximum load at failure was recorded. The static controls showed a mean maximum load to failure of 4123 N in group 1, 8357.5 N in group 2 and 5830.8 N in group 3. After dynamic loading, the specimens of group 2 reached the highest load to failure (8191.5 N), followed by group 3 (5649.5 N) and group 1 (3462 N), respectively. In group 2, we observed nine periprosthetic fractures at a load of 8400 N without signs of interface loosening. Application of an amphiphilic bonder led to a significant improvement of bonding stability, especially when glutaraldehyde was added to the bonder. This technique might offer an increased longevity of cemented femur revision stems in total hip replacement.

Wear of ultra-high-molecular-weight polyethylene (UHM-WPE) inlays is associated with aseptic loosening in total knee replacement (TKR). The aim of this study was to investigate the in vitro performance of a TKR system that combines several measures to decrease UHMWPE wear. Tests were carried out on a BPK-S Integration system (RD, P. Brehm Chirurgie-Mechanik, Weisendorf, Germany) according to ISO 14,243-1 in a knee joint simulator. Calf serum with a high protein concentration of 30 g/l was chosen as the test lubricant. PE wear was measured gravimetrically. Particle analysis was performed by scanning electron microscopy, with measurement of particle size and shape. Low mean wear rates of 1.20 mg per million cycles were found for the fixed bearing type and 2.47 mg per million cycles for the rotating-platform bearing design. Anteroposterior deflection was low. The contact areas for both types of bearings were large and showed a constant pattern throughout the test. Backside wear was obvious on rotating platforms. Particle analysis revealed equally sized and round-shaped particles in both types of bearings (fixed, 0.35 microm; mobile, 0.32 microm). In conclusion, the combination of design features and surface modifications of the BPK-S integration TKR system leads to low gravimetric UHMWPE wear.

Restoration of a painless hip joint capable of bearing weight by uncemented implantation of a rotationally stable, modular revision stem anchored in the diaphysis. Prosthetic stem loosening with osteolytic bone defects (defect classification types I–III according to Paprosky), material failure with broken prosthesis, sub-and/or periprosthetic femoral fractures, and tumors. Extensive osteolysis preventing diaphyseal anchorage of the prosthetic stem. Transgluteal approach to the hip joint. Removal of the loose prosthetic stem and, if cemented, the bone cement as well. Excision of intramedullary granulation tissue. Reaming of the medullary cavity with flexible reaming shafts and formfit, uncemented implantation of the star-shaped modular revision stem with diaphyseal press-fit. If there is extensive loss of metaphyseal bone stock, augmentation with autogenous-allogenic bone should be performed. Mobilization on two underarm crutches from the 1st postoperative day. Removal of the Redon drains after 48 hours. Partial loading with 20 kg for 6 weeks postoperatively. If plain radiographs show unchanged seating of the prosthesis after 6 weeks, loading can be increased by 10 kg per week until full weight bearing is achieved; thrombosis prophylaxis is continued throughout. Radiologic checkups will be done after 3, 6, and 12 months. After that, the patient should be checked annually. Forty-five patients (N = 48 prostheses) with an average age of 67.2 years (min/max: 42.4–87.4 years) were investigated. The average implantation time of the Modular revision prosthesis MRP-TITAN revision stem was 4.7 years (min/max: 1.0–9.0 years). The Harris hip score for Paprosky bone defect types I–III had increased from 25.6 preoperatively to 71.4 postoperatively at the time of the final follow-up (p 3 0.05). Extensively defective bone was diagnosed preoperatively in 32 patients (1Paprosky IIB). Plain radiographs showed stable anchorage without migration in 44 patients. In one case, the stem (implantation time 2.36 years) was replaced due to increasing axial subsidence (15 mm). Good integration of bone graft with subsequent defect regeneration was seen in all patients with bone trans-plant (N = 30). Postoperative dislocation occurred in six patients and required closed reduction in four cases. Open reduction was performed in two patients, whereby the external rotation angle of the prosthetic neck was corrected without dismantling the distally anchored prosthetic stem components. The mechanical failure rate over the follow-up period of 9 years was 1 out of the 48 prospectively investigated prostheses. The rate of survival according to Kaplan-Meier was 97%.

Even following the introduction of the “third generation” cementing technique, an improvement of the fixation of the acetabular component similar to that of the femoral has not been shown in clinical studies. The goal of the present study was to achieve a better stability with the use of an amphiphilic bonder while preserving the mechanically important subchondral sclerosis. In a total of 20 sheep, a cemented total hip replacement was implanted. In the treatment group (n = 10), the implantation was carried out following surface conditioning of the acetabular bed with an amphiphilic bonder. All the sheep were followed for 9 months. To assess the biocompatibility, the osseous ingrowth at the cement–bone interface was depicted with the help of an in vivo fluorescent marking of the osteoblasts. Additionally, conventional radiographs were obtained over the course of treatment. Finally, the ovine pelvic regions were split following a standardized technique allowing for histological evaluation of the cement–bone interfaces. The acetabular components of the treatment group revealed a stable cement–bone compound. In the control group, the implants were easily dislodged from their beds. This finding was consistent with the radiological and histological results, which had revealed increased, progressive lytic radiolucent lines and the interposition of fibrous tissue at the cement–bone interface in the control group compared to the treatment group. The bonder was biocompatible. Following the application of the bonder, the cemented acetabular components revealed an improved stability without signs of inflammation or neoplasia in a viable acetabular osseous bed. With the help of this technique, the in vivo longevities of cemented acetabular components can be increased in the clinical setting without sacrificing the biomechanical relevant subchondral sclerosis.

The goal of this study was to evaluate the diagnostic performance of 3-Tesla MRI for the assessment of degenerative meniscal tears in clinical practice. In patients with chronic knee pain, a negative history of acute trauma and a mean age of 52 years, 3-Tesla MRI were performed a few days prior to arthroscopy. In 86 menisci, diagnostic values of 3-Tesla MRI for the detection of degenerative tears were evaluated using arthroscopy as reference standard. The MRI classification, for meniscus diagnostics, described by Crues was used. At arthroscopy, all tears identified (19 horizontal, 7 complex, 3 radial) were degenerative as confirmed by histological examination. MRI grade II lesions had a prevalence of 24% and a rate of 24% of missed tears, whereas grade I lesions were not associated with a torn meniscus at arthroscopy. For meniscal tears, (grade III) sensitivity and specificity of 3-Telsa MRI was 79 and 95% for both menisci, 86 and 100% for the medial meniscus, and 57 and 92% for the lateral meniscus. The best diagnostic performance was found for complex tears, horizontal tears showed relatively good results, poor results were documented for radial tears. For the medial meniscus, where horizontal and complex tears were more prevalent, 3-Tesla MRI shows a higher accuracy than for the lateral meniscus. Particularly with regard to the medial meniscus, 3-Tesla MRI could be effectively used when a degenerative tear is suspected. Nevertheless, in regard to a remarkable number of false positive and false negative findings the diagnostic value of a 3-Tesla MRI investigation should not be overestimated.

This is a prospective review of 135 HA-coated ABG I total hip arthroplasty (THA) systems with a mean clinical and radiographic follow-up of 8.5 years. The 5-year survival rate was 85%, but 22% of the patients were dissatisfied. Revision THA was already indicated in 28% of the patients, with 26% indicated for cup loosening. PE wear was detected by x-ray in 42%. Disproportionate substantial wear with an average linear loss of 2.6 mm at the inner rim of the insert was observed in 23% of the cases. The mean annual wear rate was calculated 0.1–0.25 mm/year. Laboratory examination of the retrieved PE revealed polishing, cracks, and subsurface delamination. Radiographic evidence of acetabular cysts were found to be excessive granuloma during surgery. Polarization microscopy revealed debris particles phagocytized by reticuloendothelial cells. Results confirm the general opinion that aseptic osteolysis is a cell-mediated process driven by the presence of particles generated from wear debris. The findings also suggest that the main reasons for the failure of the first-generation ABG hip system were an insufficient locking mechanism and poor PE congruency, and not solely poor PE quality.

BackgroundOne of few persisting problems of cemented total knee arthroplasty (TKA) is aseptic loosening of tibial component due to degradation of the interface between bone cement and metallic tibial shaft component, particularly for surface cemented tibial components. Surface cementation technique has important clinical meaning in case of revision and for avoidance of stress shielding. Degradation of the interface between bone cement and bone may be a secondary effect due to excessive crack formation in bone cement starting at the opposite metallic surface.MethodsThis study was done to prove crack formation in the bone cement near the metallic surface when this is not coated. We propose a newly developed coating process by PVD layering with SiOxto avoid that crack formation in the bone cement. A biomechanical model for vibration fatigue test was done to simulate the physiological and biomechanical conditions of the human knee joint and to prove excessive crack formation.ResultsIt was found that coated tibial components showed a highly significant reduction of cement cracking near the interface metal/bone cement (p < 0.01) and a significant reduction of gap formation in the interface metal-to-bone cement (p < 0.05).ConclusionCoating dramatically reduces hydrolytic- and stress-related crack formation at the prosthesis interface metal/bone cement. This leads to a more homogenous load transfer into the cement mantle which should reduce the frequency of loosening in the interfaces metal/bone cement/bone. With surface coating of the tibial component it should become possible that surface cemented TKAs reveal similar loosening rates as TKAs both surface and stem cemented. This would be an important clinical advantage since it is believed that surface cementing reduces metaphyseal bone loss in case of revision and stress shielding for better bone health.

One of the main causes of cup loosening in cemented total hip replacement is the lack of a hydrolysis stable compound between the hydrophobic bone cement and the hydrophilic acetabular bone stock. Thus, the long-term adhesive strength between bone and bone cement is decreased resulting in premature aseptic loosening. Accordingly, an amphiphilic bonding system was developed to prevent hydrolytic debonding in the interface bone-to-bone cement.Polyethylene cups were cemented in cadaver sheep hips. The hips were prepared with (n = 10) a multilayer bonding system as well as with an improved monolayer bonding system with (n = 10) and without (n = 10) UV-light hardening. The hips were dynamically loaded (10(6) cycles; 3 Hz; upper/lower load 1,500/200 N) and afterwards turned out with a defined strength to determine the interface compound strength. Dynamically loaded cemented cups without using the bonding system (n = 10) function as a control group.The interface adhesive strength improved significantly by a factor of 1.9 (using the multilayer bonding system) compared to the unconditioned ones (Por = 0.05); for the monolayer bonding system without (with) UV-light hardening the compound strength was 11.9-fold (or =22.2-fold) higher (Por = 0.001).The bonding system significantly improves the adhesive strength between bone and bone cement in cemented cup arthroplasty.

Two major complications of hip replacement are loosening and infection. Reliable differentiation between these pathological processes is difficult since both may be accompanied by similar symptoms. Our aim was to assess the diagnostic ability of triple-phase bone scanning (TPBS) and positron-emission tomography (PET) to detect and differentiate these complications in patients with a hip arthroplasty. Both TPBS and PET were performed in 63 patients (92 prostheses). The radiotracer for PET imaging was 18F-fluorodeoxyglucose (FDG). Image interpretation was performed according to qualitative and quantitative criteria although the final diagnosis was based upon either surgical findings or clinical follow-up. The sensitivity, specificity and accuracy of PET was 0.94, 0.95 and 0.95 respectively, compared with 0.68, 0.76 and 0.74 for TPBS. We found that an image interpretation based exclusively upon quantitative criteria was inappropriate because of its low selectivity. The histological examination indicated that increased periprosthetic uptake of FDG in patients with aseptic loosening was caused by wear-induced polyethylene particles and the subsequent growth of aggressive granulomatous tissue.

Background Artificial joint replacement of hip (HPRO) and knee (KPRO) are 2 of about 20 categories of operative procedures of the surveillance of surgical site infection (SSI) as stated by nosocomial infections surveillance systems in the United States and in Germany. Periprosthetic SSI can manifest itself after a long period. Methods Seven hundred fifty-six orthopedic patients from 2 centers were evaluated after HPRO (n = 508) or KPRO (n = 248). SSI was recorded during hospitalization and for 12 month postdischarge. The surveillance regimen was extended by also sending patients a questionnaire after 12 months postdischarge. All complaints were followed up by contacting the patients and any clinicians and general practitioners (GPs) involved. Stratified infection rates and standardized infection ratio (SIR) were calculated and compared with reference data of the national surveillance system. Results The total response rate to the postal questionnaire survey was 85.2%. SSI was recorded in 16 patients (3.15%) after HPRO; 12 were detected by predischarge surveillance, and the 4 cases found postdischarge were all organ/space SSI. In total, only 1 SSI was detected after KPRO before discharge and none after discharge (SSI rate 0.40%). Time between discharge and detection of SSI cases ranged from 8 days to 8 months. SIR of HPRO was 1.25 and SIR of KPRO was 0.36. Conclusion Because 25% of SSIs after HPRO occurred after discharge and all were organ/space SSI, highlights the importance of postdischarge surveillance of nosocomial infections (NIs). Because all SSIs were reported already by current surveillance, the extended postdischarge surveillance appears to be unnecessary. The pursuit of shorter hospital stay after surgery may challenge the methods of surveillance systems in future.

This case report demonstrates that active legionellosis is not always characterised by pulmonary symptoms and specific radiomorphological findings. Whereas the initial clinical presentation, as described in the literature, includes fever, cough, expectoration, extrapulmonary organ changes or typical laboratory findings, atypical manifestations such as reactive arthritis must be considered.

Medical implants and prostheses (artificial hips, tendono- and ligament plasties) usually are multi-component systems that may be machined from one of three material classes: metals, plastics and ceramics. Typically, the body-sided bonding element is bone. The purpose of this contribution is to describe developments carried out to optimize the techniques , connecting prosthesis to bone, to be joined by an adhesive bone cement at their interface. Although bonding of organic polymers to inorganic or organic surfaces and to bone has a long history, there remains a serious obstacle in realizing long-term high-bonding strengths in the in vivo body environment of ever present high humidity. Therefore, different pretreatments, individually adapted to the actual combination of materials, are needed to assure long term adhesive strength and stability against hydrolysis. This pretreatment for metal alloys may be silica layering; for PE-plastics, a specific plasma activation; and for bone, amphiphilic layering systems such that the hydrophilic properties of bone become better adapted to the hydrophobic properties of the bone cement. Amphiphilic layering systems are related to those developed in dentistry for dentine bonding. Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body. The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m). This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body.

The instability of the upper and the lower ankle joint represents a serious problem in patients with fibular aplasia. None of the previous techniques demonstrated at least sufficient results. In this report we present a new technique of malleolus externus plasty applied in a 5 1/2-year-old boy with fibular aplasia (type II according to Coventry and Johnson or type Ib according to Achtermann and Kalamchi) with a 6 cm length deficiency of the lower leg and 1 cm of the upper leg. Furthermore, he showed a tibial antecurvation deformity of 20 degrees, a fourth ray foot with adduction deformity of the hindfoot, cutane syndactyly D 2-4, and a hallux varus. This new technique works on the following principle. A triangular iliac crest transplant is implanted with an apophysis and the annexing fascia glutealis, including the osseous part of the transplant, in the lateral distal tibia in a way that the growing apophyseal part lays distally covering the lateral talus. Gluteal fascia annexed to the apophysis was used for the reconstruction of a lateral tendon. Using a ring fixator the transplant is fixed and coincidentally the lower leg lengthened and the axis corrected. The axis deformity and the leg-length deficiency of 7 cm were equalized. The fixator could be removed after 6 months. Radiologically, an entire integration of the iliac crest transplant was found. Magnetic resonance imaging showed it had sufficient circulation. The reexamination 2.5 years later demonstrated a simultaneous growth of the malleolus externus and the distal tibia and stable ankle joints with sufficient mobility and full weight-bearing capability. For support of the foot the boy uses ready-made shoes with curved arch supports. In conclusion, using this new technique an individually adapted lateral malleolus with growth-potential can be constructed that stabilizes the foot and the ankle joints. Thus, reluxations of the foot specifically in relation to lengthening of lower legs can be avoided with concurrent preservation of the range of movement of the ankle joint.

Acquired von Willebrand disease (aVWD) is a rare bleeding disorder that mimics congenital VWD in previously healthy individuals; it is most frequently associated with monoclonal gammopathy. Hemostatic therapy of aVWD is challenging due to the extremely shortened half-life of endogenous and exogenous VWF. High-dose intravenous immunoglobulin (ivIG) is recommended as the treatment of choice, usually rapidly normalizing coagulation; but in case of failure, alternative treatment options are not well explored. We report successful major orthopedic surgery in a 61-year-old woman with multiple myeloma IgG lambda and aVWD. IvIG alone failed to correct hemostasis. However, ivIG pretreatment improved the VWF ristocetin cofactor (VWF:RCo) half-life from only 1.5 hr to more than 4 hr, allowing desmopressin infusions twice daily to maintain sufficient VWF:RCo levels. Because of diminishing desmopressin effect, we attempted for the first time in aVWD a continuous VWF/FVIII infusion (Haemate HS), 2.1-2.7 FVIII U/kg/hr or 51-64 U/kg/day, respectively 4.6-6.0 VWF:RCo U/kg/hr or 110-145 U/kg/day) to reach constant factor levels. The steady-state clearance was 2.4 mL/kg/hr for FVIII:C and 13.5 mL/kg/hr for VWF:RCo. During surgery, VWF:RCo, FVIII:C, and PFA-100 closure time were normalized. Until day 5, VWF:RCo was kept above 50%, from day 6 to 10 at least 30% activity were attained. FVIII:C levels were always >70%. The clinical course was uneventful without bleeding. Two weeks after hip surgery the patient was discharged from the hospital without complaints. The therapy described can be recommended as safe and feasible for further evaluation in aVWD patients who are hyporesponsive to ivIG treatment alone. Continuous VWF/FVIII infusion can improve substitution therapy in aVWD.

In recent years, many biochemical markers were tested with the aim of developing a tool for the early detection and monitoring of osteoarthritis (OA). Apart from chondral markers, we also evaluated osseous markers from the synovial fluid to obtain more comprehensive information, and we compared the levels in relation to the severity of OA. In this prospective, cross-sectional study, synovial fluid samples were obtained from 73 patients with OA of the knee joint prior to operation and after the joint was flushed with 50 ml of normal saline. All patients underwent surgery and were classified in accordance with the Outerbridge and the Noyes classification. The measured biochemical markers included pyridinoline (PD), deoxypyridinoline (DPD), N-telopeptide (NTx), carboxyterminal propeptide of collagen-1 (PICP), matrix metalloproteinases (MMP-1 and MMP-3), and tissue inhibitor of MMPs (TIMP-1). The marker levels were normalized against the total protein content and were compared with the Outerbridge and the Noyes classification. For the majority of markers, the correlation coefficient was below r=0.3, with large 95% confidence intervals. The highest correlation coefficients were obtained from DPD and TIMP-1. In relation to the Outerbridge classification, DPD revealed high values only in stage IV. The overall results indicate that the majority of the tested markers are unspecific with regard to the different stages of OA. The two markers with the highest correlation coefficients showed no major sensitivity to detect OA at an initial stage. However, they might give additional information to clinical and radiological findings with regard to the severity of the disease.

Fifty-one patients with septic arthritis of the knee were reviewed retrospectively. Twenty-seven patients had been treated by arthroscopic lavage and debridement, 24 patients by open arthrotomy with subtotal synovectomy. The patients were staged according to the duration of preoperative symptoms and to the intraoperative spread of the inflammatory process. With early onset of therapy (less than 5 days) and without osseous involvement arthroscopic treatment led to an effective resolution of infection with better functional results than open arthrotomy.

Einleitung Auch bei strenger Indikation hat das laterale Release (LR) der Patella in bis zu 30% Komplikationen wie Rezidiv der Hyperkompression oder mediale Patella-Instabilitat. Daher wurde statt der Durchtrennung eine z-Verlangerung des lateralen Retinakulum-Kapsel-Komplexes (LV) propagiert. Hypothese LV reduziert die Komplikationen des LR bei gleicher Schmerzreduktion. Methode 08/2006–09/2008 wurden 28 Patienten (21 w, 7 m, Durchschnittsalter 42,5 Jahre) mit HKS der Patella, abwechselnd entweder mittels LR (14 Patienten) oder LV (14 Patienten) uber eine einheitliche laterale parapatellare Hautinzision operiert. Operateur, Wundverschluss und Rehabilitationsschema waren gleich. Praoperativ, nach 3, 6, 12 und 24 Monaten erfolgte eine Dokumentation mittels Fragebogen zu Schmerz und Funktion (Kujala Score: 0–100 Punkte), mit Hilfe einer Visual Analog Scala zu Schmerzen (VAS, 0–10 Punkte), Untersuchung zur Hyperkompression (passiver Patella Tilt: positiv-negativ (PPT) und mediale Patella Verschieblichkeit: 0–4 Quadranten (MLV) nach Kolowich), Stabilitat (Gravitation-Subluxations-Test nach Nonweiler: positiv-negativ (GST)) und Quadrizepsatrophie (Oberschenkelumfang in cm, 10 cm oberhalb der Patella). Dies erfolgte durch zwei Personen, ohne Wissen uber das operative Vorgehen. Ergebnisse Die mittlere Nachkontrollzeit betrug beim LR 21,4 Monate (m) und bei LV 21,7 m (Range jeweils 18–24 m). Von praoperativ zur letzten Kontrolle anderten sich die Variablen wie folgt: Kujala Score verbesserte sich signifikant fur LR (p 0,05). Bei der MLV fur LR anderte sich der Mittelwert von 0,4 Quadranten (Q) zu 2,5 Q (Range, 1–4Q), fur LV von 0,4 zu 1,6 Q (Range, 0,5–2 Q), mit signifikantem Unterschied (p Diskussion LR und LV eignen sich zur Therapie des HKS der Patella. Allerdings zeigt die LV eine kontrolliertere mediale Patella Verschieblichkeit (niedrigere Range der Werte bei MLV) ohne mediale Instabilitat und ohne deren Risikofaktor einer Quadrizepsatrophie, was durch das Erhalten der Kontinuitat des Retinakulum-Kapsel-Komplexes erklart wird. Die Auswirkungen dieser Unterschiede zeigen sich auch in den besseren subjektiven Bewertungen (Kujala Score). Bis zum GOTS-Jahreskongress wird die prospektive Studie abgeschlossen sein (alle Patienten werden bis Juni 2010 mindestens 24 Monate nachkontrolliert sein) und damit ein gultigeres Studienergebnis zu berichten sein.

In a prospective study C-reactive protein (CRP) and interleukin-6 (IL-6) measurements were taken serially in 30 patients before and after 20 total hip arthroplasties (THR) and 10 total knee arthroplasties (TKR). There were no peri- and postoperative complications. Postoperatively the IL-6 serum concentration increased rapidly and peaked 6 h postoperatively at maximum levels (399+/-140 pg/ml). There was a mean half-life of 15 h and thereafter a rapid return to normal concentrations. In comparison, the postoperative CRP concentration rose more slowly and reached maximum levels (138+/-54 mg/l) on the second postoperative day. There was thereafter a slow descent with a mean half-life of 62 h. There was no significant difference between the patients with THR and those with TKR (P0.05). IL-6 is therefore a superior marker for the inflammatory phase after THR and TKR.

We present the early results of 142 uncemented femoral stem revisions using the modular MRP-Titan system. There were 70 cases with marked preoperative femoral bone defects (Paprosky type 2C and type 3); and bone grafts were used in 31 cases. At a mean follow-up of 2.3 years five cases were re-revised due to dislocation and two due to aseptic loosening. The mean Harris hip score improved from 37.4 preoperatively to 92.4. In 122 cases progressive bone regeneration on X-ray was seen; and no further osteolysis was observed.

Fifty-nine patients with spondylodiscitis (SD) of the thoracic and/or lumbar spine were followed-up clinically and radiologically [X-ray, computed tomography (CT), magnetic resonance imaging (MRI)] over a mean time of 2.2 years (1–6.5 years). All patients without abscess formation (n = 35) were treated conservatively. Out of the group with abscess formation (n = 24) 6 patients were also treated conservatively, 11 were drained under CT control and 7 were operated. At time of diagnosis, “signs of florid inflammation” were seen in 60% of the roentgenograms, in 93% of the CTs and in all of the MRIs. The sensitivity to differentiate between SD with and without abscess formation was 85% by MRI and 69% by CT. “Signs of regressive inflammation” and “signs of increasing osseous consolidation”, essential facts for starting remobilization, could first be seen using CT 6 weeks after onset of therapy. Using MRI these signs were seen with a considerable delay at 12 weeks. Clinically, only 3 of the 59 analyzed patients developed recurrent SD. In conclusion, MRI is the radiological method of choice for establishing the diagnosis of SD, in particular with regard to differentiating between cases with and without abscess formations. In contrast, CT is superior for performing success control after treatment. Therapeutically, conservative, minimal-invasive and operative procedures are not rival but rather complementary.

Die rasante Entwicklung der Computertechnologie hat zu einer Umorientierung von Arbeits- und Verhaltensweisen in vielen Bereichen des taglichen Lebens gefuhrt. Schlagworte wie Internet oder Virtual Reality sind Gegenstand der offentlichen Diskussion und haben grose Auswirkungen auf das Freizeitverhalten des modernen Menschen. Nur indirekt spurbar hingegen ist der Nutzen, den Forschung und Wissenschaft aus der gewaltigen Steigerung der Rechenleistung heutiger Computer in den letzten Jahren gezogen haben. In medizinischer Hinsicht sind dies vor allem neue Diagnoseverfahren und Operationstechniken, die grosere Heilungserfolge ermoglichen. Am Beispiel kunstlicher Huftgelenke soll hier eine Perspektive aufgezeigt werden, wie der Einsatz einer individuellen Operationsplanung und -durchfuhrung in der Zukunft aussehen konnte.

Horner's syndrome after trauma is rare. After visual diagnosis, a search for the cause is urgent due to possible life threatening damage. Intracerebral bleeding and carotid dissection must be excluded. Traumatic Horner's syndrome often seems to be, as in the case described here, caused by a fracture of the first rib. As persistent symptoms are not described, conservative therapy is recommended.

Background Since the 1990s, balloon kyphoplasty has been proven as an effective method of treating patients with painful vertebral compression fractures (VCF). However, due to the low viscosity of the PMMA cement uncontrollable cement leakage with corresponding risks is often the focus of discussions on this procedure. The Radiofrequency Kyphoplasty is an innovative procedure available since 2009, for which an ultra-high viscosity cement is used. It also offers the advantage of over 30 minute’s constant processing time. Objectives For the statistical comparison of the two methods of augmentation clinical and radiological data of 2 larger patient groups were evaluated. Methods As part of the surgical treatment of patients with conservative therapy-resistant osteoporotic vertebral fractures a prospective study of radio frequency kyphoplasty (RFK) was performed between 2009 and September 2010.From the clinical aspect, measurement parameters for efficacy and safety were the course of pain intensity using a visual analogue scale (VAS: 0 to 100 mm) and the Oswestry Disability Score (0-100%). For the radiological outcome the increase in the middle and anterior parts of the treated vertebra and also the reduction of kyphosis after surgery and after 6 months were evaluated. Furthermore, the extent of cement extrusion and the duration of operation time were compared. There were 2 groups of patients chosen with the same indication, and with the same average VAS prior to treatment. For the balloon kyphoplasty (BKP) the Kyphon ® technology was used. For the BKP-group the same parameters like in the first group were evaluated (matched pairs). To compare the data statistically parametric and nonparametric tests were applied. Results For the radio frequency kyphoplasty group (RFK) 114 patients were recruited, and for the balloon kyphoplasty group (BKP) 114 appropriate patients were selected. In 48% of the RFK-patients and in 44% of the BKP-patients more than one vertebral body were treated (thoracic or lumbar). Prior to treatment 84 mm on the VAS were calculated in both groups. The decrease in VAS values was (RFK vs. BKP) immediately after surgery, 58.8 mm vs.54.7 mm (p=0.02), and 73.0 vs. 58.9 mm after 6 months (p Concerning cement leakage a key difference in favor of the radio frequency kyphoplasty was detected (6.1% vs. 27.8%; p Conclusions The RFK has proven to be a clinically very effective procedure that does somewhat better than BKP in long-lasting pain relief. No differences could be detected regarding improvement of functioning and the mean restoration of mid- and anterior vertebral height. As the safety aspect is concerned the RFK offers the advantage of a statistically significant lower proportion of cement extrusion. Disclosure of Interest None Declared

Background There is controversy about how to treat vertebral fractures. Conservative care is the default approach, despite lack of evidence. Radiofrequency kyphoplasty uses ultrahigh viscosity cement to restore spinal posture and stabilize the fracture. Objectives The aims of this study were to compare radiofrequency kyphoplasty to conservative care and assess the usual algorithm of starting all patients on conservative care for 6 weeks before offering surgery. Methods Elderly patients with painful osteoporotic vertebral compression fractures were all treated with 6 weeks of conservative care (analgesics, bracing, and physiotherapy). They were then offered the choice of continuing conservative care or crossing over to radiofrequency kyphoplasty, at 6 and 12 weeks. Clinical success was defined as: 1) VAS pain improvement ≥2, 2) final VAS pain ≤5, 3) no functional worsening on ODI. Results After the initial 6 weeks of conservative care, only 1 of 65 patients met the criteria for clinical success, and median VAS improvement was 0. After 12 weeks of conservative care, only 5 of 38 patients met the criteria for clinical success, and median VAS improvement was 1. At the 6 week follow-up after radiofrequency kyphoplasty, 31 of 33 surgery patients met the criteria for clinical success, and median VAS improvement was 5. Conclusions For the vast majority of patients, conservative care did not provide meaningful clinical improvement. By contrast, nearly all patients who underwent radiofrequency kyphoplasty had rapid substantial improvement. Surgery was clearly much more effective than conservative care and should be offered to patients much sooner. Disclosure of Interest None Declared