dGEMRIC as a tool for measuring changes in cartilage quality following high tibial osteotomy:A feasibility study

SummaryObjectiveThe high tibial osteotomy (HTO) is an effective strategy for treatment of painful medial compartment knee osteoarthritis. Effects on cartilage quality are largely unknown. Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) enables non-invasive assessment of cartilage glycosaminoglycan content. This study aimed to evaluate if dGEMRIC could detect relevant changes in cartilage glycosaminoglycan content following HTO.DesignTen patients with medial compartment osteoarthritis underwent a dGEMRIC scan prior to HTO, and after bone healing and subsequent hardware removal. A dGEMRIC index (T1Gd) was used for changes in cartilage glycosaminoglycan content, a high T1Gd indicating a high glycosaminoglycan content and vice versa. Radiographic analysis included mechanical axis and tibial slope measurement. Clinical scores [Knee Osteoarthritis Outcome Scale (KOOS), visual analogue score (VAS) for pain, Knee Society Clinical Rating System (KSCRS)] before, 3 and 6 months after HTO and after hardware removal were correlated to T1Gd changes.ResultsOverall a trend towards a decreased T1Gd, despite HTO, was observed. Before and after HTO, lateral femoral condyle T1Gd was higher than medial femoral condyle (MFC) T1Gd and tibial cartilage T1Gd was higher than that of femoral cartilage (P < 0.001). The MFC had the lowest T1Gd before and after HTO. Clinical scores all improved significantly (P < 0.01), KOOS Symptoms and QOL were moderately related to changes in MFC T1Gd.ConclusionsdGEMRIC effectively detected differences in cartilage quality within knee compartments before and after HTO, but no changes due to HTO were detected. Hardware removal post-HTO seems essential for adequate T1Gd interpretation. T1Gd was correlated to improved clinical scores on a subscore level only. Longer follow-up after HTO may reveal lasting changes.ClinicalTrials.gov registration ID: NCT01269944

Effects of pretension in reconstructions of the anterior cruciate ligament: clinical, biomechanical and computer model analyses

This study consists of a contextual analysis of a group of Central Anatolian Neolithic settlements that includes the sites of Aşıklı Höyük, Canhasan III, Çatalhöyük,Erbaba, and Canhasan I, and can be dated between 8500 and 5500 Calibrated BC. These settlements are characterised by a spatial organisation in which buildings are grouped in neighbourhood clusters and in which an estimated 30 to 40 households would have lived. These neighbourhoods lack streets, and the buildings within them were accessed from the roof level. The study explores the social significance of this form of organisation of settlement space at a number of levels. First, the nature of the individual buildings and how these related to household is investigated. Second, non-domestic features in these settlements, such as sub-floor burials, are contextualised in order to identify status differentiation between buildings. Third, the scale and composition of clustered neighbourhoods is studied, to arrive at a better understanding of their significance. Finally, the manner in which neighbourhoods in a settlement related to one another and the ways in which settlements were part of larger settlement systems is considered. In this manner new light is shed on the social structure of these Central Anatolian Neolithic communities</p

Effects of pretension in reconstructions of the anterior cruciate ligament: clinical, biomechanical and computer model analyses

Contains fulltext : 146607.pdf (Publisher’s version ) (Open Access)125 p

Mechanism of bone incorporation of beta-TCP bone substitute in open wedge tibial osteotomy in patients.

Contains fulltext : 47508.pdf (publisher's version ) (Closed access)A histological study was performed of bone biopsies from 16 patients (17 biopsies) treated with open wedge high tibial osteotomies for medial knee osteoarthritis. The open wedge osteotomies were filled with a wedge of osteoconductive beta tricalcium phosphate (beta-TCP) ceramic bone replacement. At the time of removal of the fixation material, core biopsies of the area where the beta-TCP was located were taken at different follow-up periods (6-25 months). beta-TCP resorption, bone ingrowth and bone remodelling were studied. We hypothesized that the incorporation and remodelling process occurs similarly as in animals. Histology showed a good resorption of the beta-TCP with complete incorporation and remodelling into new bone. The different phases as described in animal studies were found. A correlation was found between histological findings and radiological assessment. In conclusion, beta-TCP appeared to be a bone replacement material with optimal biocompatibility, resorption characteristics and bone conduction properties for the clinical use

Anterior Open-Bite Diagnosis And Treatment

BACKGROUND: The opening wedge approach to high tibial osteotomy (HTO) is perceived to have some advantages relative to the closing wedge approach but it may be associated with delayed and nonunions. Because nonunions evolve over months, it would be advantageous to be able to identify risk factors for and early predictors of nonunion after medial opening wedge HTO. QUESTIONS/PURPOSES: We sought to determine whether (1) preoperatively identifiable patient factors, including tobacco use, body mass index > 30 kg/m(2), and degree of correction, are associated with nonunion, and (2) a modified Radiographic Union Score for Tibial Fractures (RUST) score, taken at 6 weeks and 3 months, would be predictive for delayed or nonunion after medial opening wedge HTO. METHODS: The medical records and radiographs of 185 patients, 21 bilateral cases, treated with a medial open wedge HTO using the TomoFix((R)) device were retrospectively evaluated. For all patients, demographic data regarding risk factors were collected from their records. Diagnosis for delayed or nonunion was already done earlier for standard medical care by the orthopaedic surgeon based on clinical and radiographic grounds. For the retrospective radiographic evaluation, a modified RUST score was used in which each tibial cortex is scored by one observer. Logistic regression analysis was used to identify preoperative and postoperative predictive factors for developing delayed or nonunion. In the series, a total of 19 patients (9.2%) developed clinically delayed/nonunion of whom 10 patients (4.9%) developed a nonunion. RESULTS: Smoking was identified as a risk factor for developing delayed/nonunion (19% for smokers versus 5.4% for nonsmokers; p = 0.005; odds ratio, 4.1; 95% confidence interval, 1.5-10.7). By contrast, body mass index, lateral cortical hinge fracture, age, infection, and degree of correction were not risk factors. Patients with delayed/nonunion had lower RUST scores at all time points when a radiograph was taken compared with the total study group. CONCLUSIONS: The RUST score at 6 weeks and 3 months after surgery and the use of tobacco were identified as predictive factors for development of delayed union and nonunion after open wedge HTO. Based on these results, we now actively try to stop patients from smoking and these data are helpful in doing that. The RUST score may be of use to identify which patients are at risk for developing a delayed union so that interventions may be offered earlier in the course of care. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence

Valgus bracing in patients with medial compartment osteoarthritis of the knee. A gait analysis study of a new brace.

Contains fulltext : 51655.pdf (publisher's version ) (Closed access)A new valgus brace was evaluated in 15 patients with medial osteoarthritis of the knee and a varus leg axis. Significant improvement of pain and function were found after 6 weeks of brace treatment. Gait analysis showed that the brace had a tendency of lowering the peak varus moment about the knee. This effect was more profound in the presence of higher initial varus deformity angle of the knee. Furthermore, bracing led to a small decrease of knee extension at the end of the swing phase and an increase of walking velocity. The mechanisms identified by gait analysis in this study may be of clinical importance for future developments in brace treatment