Performance of cementitious systems containing calcined clay in a chloride-rich environment: a review by TC-282 CCL.

In this review by TC- 282 CCL, a comprehensive examination of various facets of chloride ingress in calcined clay-based concrete in aggressive chloride-rich environments is presented due to its significance in making reinforced concrete structures susceptible to chloride-induced corrosion damages. The review presents a summary of available literature focusing on materials characteristics influencing the chloride resistance of calcined clay-based concrete, such as different clay purity, kaolinite content and other clay minerals, underscoring the significance of pore refinement, pore solution composition, and chloride binding mechanisms. Further, the studies dealing with the performance at the concrete scale, with a particular emphasis on transport properties, curing methods, and mix design, are highlighted.

External Sulfate Attack on Cementitious Binders: Limitations and Effects of Sample Geometry on the Quantification of Expansion Stress.

The hollow cylinder method was used to estimate the expansion stress that can occur in concrete due to the crystallisation pressure caused by the formation of ettringite and/or gypsum during external sulphate attack. Hardened cement paste hollow cylinders prepared with Portland cement were mounted in stress cells and exposed to sodium sulphate solutions with two different concentrations (3.0 g L SO and 30.

Experimental Carbonation Study for a Durability Assessment of Novel Cementitious Materials.

Durability predictions of concrete structures are derived from experience-based requirements and descriptive exposure classes. To support durability predictions, a numerical model related to the carbonation resistance of concrete was developed. The model couples the rate of carbonation with the drying rate.

[Amputation of the leg with impaired circulation. The orthopaedic surgeon's view].

Despite therapeutic improvements in the treatment of arterial circulatory problems of the leg, several tens of thousands of amputations are performed every year. The amputation is not the end of the treatment but is the beginning of the rehabilitation. Decisive criteria for a successful rehabilitation are the quality of the leg-stump, the immediate and early care, and an adequate artificial leg.

Cementless CUT femoral neck prosthesis: increased rate of aseptic loosening after 5 years.

Background: Bone-saving hip arthroplasty techniques, which facilitate revision, are gaining importance as the number of hip replacements in younger patients increases.

Patients And Methods: 123 CUT femoral neck prostheses (ESKA Implants, Lübeck, Germany) were implanted in 113 patients (average age 53 years) between 1999 and 2002. After a mean follow-up of 5 (3-7) years, we determined the state of 120 prostheses; 3 patients could not be located.

[Medium-term results of the cementless femoral neck prosthesis CUT].

Aim: The present work aims at evaluating the clinical and radiological midterm results of the femoral neck prosthesis CUT.

Method: 67 femoral neck prostheses of the type CUT were implanted in 63 patients between 4/1999 and 5/2003 (average age 56 years). At an average follow-up time of 5.

[The femoral neck prosthesis CUT. Three- to six-year results].

Background: As the number of younger patients undergoing total hip arthroplasty is growing steadily, bone-saving implantation techniques are increasingly gaining in importance.

Methods: Fifty-six femoral neck prostheses (type CUT, ESKA Implants, Lübeck, Germany) were implanted in 50 patients between 1999 and 2002 (average age 49 years). After a mean follow-up of 4.

[Long-term results with the Harris-Galante press-fit-cup].

Aim: The present work aims at evaluating the clinical and radiological long-term results of the Harris-Galante press-fit cup.

Method: At an average follow-up time of 9.5 years (min.

Strength and voluntary activation of the quadriceps femoris muscle at different severities of osteoarthritic knee joint damage.

Objective: Improvements of quadriceps motor deficits represent a major therapeutical target in knee osteoarthritis (OA). In the present study, we investigated changes in quadriceps function at different stages of osteoarthritic cartilage damage.

Methods: Measurements of quadriceps voluntary activation (VA) and maximum voluntary contraction (MVC) were performed by a twitch interpolation technique and the total muscular capacity (TMC) was calculated as the ratio of MVC and VA.

Higher susceptibility to Fas ligand induced apoptosis and altered modulation of cell death by tumor necrosis factor-alpha in periarticular tenocytes from patients with knee joint osteoarthritis.

The aim of the present study was to investigate the expression of Fas in periarticular tenocytes of patients with osteoarthritis (OA) and to study their susceptibility to Fas ligand-mediated apoptosis. Tendon samples were obtained from the quadriceps femoris muscle of patients with knee OA and used for histological evaluation, for immunohistochemical detection of Fas, and to establish tenocyte cultures. The expression of Fas mRNA was determined by quantitative PCR.

Osteoclast-independent bone resorption by fibroblast-like cells.

To date, mesenchymal cells have only been associated with bone resorption indirectly, and it has been hypothesized that the degradation of bone is associated exclusively with specific functions of osteoclasts. Here we show, in aseptic prosthesis loosening, that aggressive fibroblasts at the bone surface actively contribute to bone resorption and that this is independent of osteoclasts. In two separate models (a severe combined immunodeficient mouse coimplantation model and a dentin pit formation assay), these cells produce signs of bone resorption that are similar to those in early osteoclastic resorption.

Kinesthetic sense of the shoulder in patients with impingement syndrome.

A proprioceptive deficit is an important determinant of disability in various shoulder disorders, such as instability and osteoarthrosis. In 15 patients with impingement syndrome stage II (Neer 1983), who were treated by arthroscopic subacromial decompression, we measured movement sense by determining threshold levels for the perception of motion of the shoulder. The patients were placed in a specially designed chair allowing continuous passive motion of the shoulder joint, while avoiding cutaneous, auditory and visual stimuli.

Quadriceps muscle function after high tibial osteotomy for osteoarthritis of the knee.

In patients with osteoarthritis of the knees, quadriceps muscle dysfunction is an early and common clinical feature and an important determinant of disability. In the current study, changes in quadriceps muscle strength and voluntary quadriceps muscle activation after high tibial osteotomies for primary osteoarthritis of the knee in 19 patients were investigated. Quadriceps muscle function was assessed during different degrees of isometric maximum voluntary contraction using a specially built chair.

Strength and motion after hemiarthroplasty in displaced four-fragment fracture of the proximal humerus: 27 patients followed for 1-6 years.

We evaluated 27 patients with shoulder hemiarthroplasty after displaced four-fragment fracture of the proximal humerus after mean 4 (1-6) years. Isometric strength measurements (Kintrex) and three-dimensional motion analysis (Elite-System) were performed on the operated and unoperated shoulders. Clinical assessment was based on Constant's score and Neer's scoring system.

Evaluation of quadriceps strength and voluntary activation after unicompartmental arthroplasty for medial osteoarthritis of the knee.

Introduction: In early and moderate stages of osteoarthritis (OA) of the knee, arthrogenous muscle inhibition (AMI) is an important factor for the initiation and the progression of the disease. Although AMI has been shown to be reduced after physiotherapeutical exercises resulting in significant improvements in disability, implantation of unicondylar knee arthroplasties is much provided in these stages of OA. Therefore, in the present study we investigate changes in quadriceps muscle after implantation of such prostheses as compared to physiotherapeutical treatment, alone.

[History of German orthopedics 1989-2001].

The present article describes essential aspects of the development of German orthopedics from 1989 to 2001. Special attention is given to the unification of the two German orthopedic groups after the political turnaround in the German Democratic Republic and the resultant changes in the landscape of German orthopedics. In addition, further milestones in the development of German orthopedics during the last 10 years are presented, e.

[Comparison of 2 surgical techniques in isolated supraspinatus rupture. A matched-pair study].

The comparison of results after open surgery methods in the repair of rotator cuff ruptures needs homogen patient groups. We compared 34 patients in 2 groups who were treated with open surgery for isolated ruptures of the supraspinatus muscles (lesion type III). Patients in group I were treated with transosseous suture refixation of the supraspinatus, in group II suture anchors (type: Corkscrew) were used.

Development and characteristics of a synovial-like interface membrane around cemented tibial hemiarthroplasties in a novel rat model of aseptic prosthesis loosening.

Objective: Aseptic prosthesis loosening (APL) is related to the formation and aggressive growth of a synovial-like interface membrane (SLIM) between prosthesis and bone. However, investigation of the early phases of SLIM development in humans presents major difficulties. This study was undertaken to develop and characterize the usefulness of a novel animal model of APL that is based on an established model of defined exercise in a running wheel by Wistar rats that have been subjected to intracranial self-stimulation (ICSS).

[Recurrent luxations after arthroscopic refixation of the labrum using suture anchors in traumatic ventral shoulder luxation].

Objective: Recurrence rates after arthroscopic labral reconstruction for anterior shoulder instability are still higher than after open procedures. Therefore, proper selection of patients becomes increasingly important. The aim of this study was to investigate factors influencing recurrence rates after arthroscopic labral repair with suture anchors.

Evaluation of arthroscopic articular cartilage biopsy for osteoarthritis of the knee.

PURPOSE: Arthroscopic evaluation of the articular surface by visualization and palpation has proved to be unreliable; therefore, we investigated arthroscopically procured biopsy specimens and conventional sections by using the same histopathomorphologic techniques and compared the results for possible differences. METHODS: Cartilage biopsy specimens of 1.7 mm in diameter and conventional cartilage sections (pieces of 8 x 2 mm) were removed from the lateral femoral condyle of 53 osteoarthritis patients undergoing total knee arthroplasty.

[Calcifications after operations of the subacromial space].

Objective: Although there are several studies on the development of periarticular calcifications after different operation procedures of the joints, such calcifications have only seldomly been described in connection with operations in the subacromial space. Therefore, the present study was aimed at investigating the incidence of periarticular calcifications after operations in the subacromial space and to assess their clinical relevance.

Patients And Methods: In a retrospective study we examined 152 patients (51 female, 101 male) who had been operated on for primary shoulder impingement by open or arthroscopic procedures.

[Functional changes in the quadriceps femoris muscle in patients with varus gonarthrosis].

In osteoarthritis (OA) of the knee, arthrogenous muscle inhibition (AMI) is considered to be one of the reasons of quadricep muscle weakness. Its influence on functional impairment such as gait alterations, however, still remains unclear. Fourty-seven patients with knee OA (mean age 64 +/- 5.

[3-dimensional image analysis of the shoulder joint--a new method for characterizing parameters of shoulder joint function].

Objective: An exact assessment of shoulder movement is of special importance both in the diagnosis of and in the therapy for different shoulder diseases. Therefore, we developed a feasible method for the analysis of shoulder movement.

Methods: On the basis of an ELITE system and 6 skin markers (marker positions.

[Is unicondylar knee prosthesis a current possibility in primary management of varus gonarthrosis?--A prospective matched-pair study].

Aim: In the present study, we performed a follow-up investigation comparing middle-term results after unicompartmental and bicompartmental knee arthroplasties.

Material And Methods: We used matched pairs with 18 patients in each group. The first group was treated with the unicompartmental slegde prosthesis (Type Wessinghage), the second with the cementless nonconstrained bicondylar prosthesis (Type Natural knee).

[Joint loading as a possible etiology for arthrosis development. Results of animal experiment studies of the rat model].

We review our results with an animal model for investigations on the development of osteoarthritis (OA). This model is based on running exercises of wistar rats performed in a running wheel using intracranial self-stimulation to motivate rats to excessive running. In our studies a total of 49 rats was divided into groups with running exercises of 15 km, 20 km, and 30 km respectively.