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61.
62.
M. Petri E. Liodakis M. Hofmeister F. J. Despang M. Maier P. Balcarek C. Voigt C. Haasper J. Zeichen D. Stengel C. Krettek K. H. Frosch H. Lill M. Jagodzinski 《Archives of orthopaedic and trauma surgery》2013,133(2):209-213
Introduction
Patellar dislocation is a common knee injury with mainly lateral dislocations, leading to ruptures of the medial patellofemoral ligament in most of the cases. Even though several prognostic factors for patellofemoral instability have been identified so far, the appropriate therapy for patients with patellar dislocation remains a controversial issue. The purpose of this study was to compare the outcome after conservative or operative treatment in patients after first-time patellar dislocation.Patients and methods
This randomized controlled clinical trial was designed multicentric including patients from six German orthopaedic and trauma departments. Twenty patients with a mean age of 24.6 years with first-time traumatic patella dislocation were included and randomized into either a conservative arm or an operative arm. Plain X-ray images of the knee joint (a.p. and lateral view and tangential view of both patellae) were performed in all cases prior to therapy to exclude osteochondral fragments requiring refixation. An MRI was recommended, but not compulsory. Patients were consulted after 6, 12, and 24 months with a questionnaire including the criteria of the Kujala score, recurrent dislocation, and satisfaction.Results
The mean Kujala score of the conservative vs operative treatment group was 78.6 vs 80.3 after 6 months (p = 0.842), 79.9 vs 88.9 after 12 months (p = 0.165), and 81.3 vs 87.5 after 24 months (p = 0.339). Redislocation rate after 24 months was 37.5 % in the conservative group and 16.7 % in the operative group (p = 0.347). Due to the small number of patients that could be included, no significant difference between the groups could be detected. We see a tendency towards better results after operative treatment.Conclusion
Our multicentric prospective randomized controlled trial revealed no significant difference between conservative and operative treatment for patients after first-time traumatic patellar dislocation. However, a tendency towards a better Kujala score and lower redislocation rates for patients with operative treatment was observed. The small number of patients is a limiting factor of the study, leading to results without statistical significance. A meta-analysis including other study′s level I data is desirable for the future. 相似文献63.
Daniel Guenther Alexandra Oks Max Ettinger Emmanouil Liodakis Maximilian Petri Christian Krettek Michael Jagodzinski Carl Haasper 《International orthopaedics》2013,37(8):1605-1611
Purpose
Collagen I hydrogels are widely used as scaffolds for regeneration of articular cartilage defects. We hypothesised that ingrowth might be improved by removing the superficial layer of a compressed hydrogel. The control group consisted of the original unmodified product.Methods
The migration of human bone marrow stromal cells (hBMSCs) into the hydrogel was evaluated by confocal microscopy. We quantified the DNA concentration of the hydrogel for each group and time point and evaluated the chondrogenic differentiation of cells.Results
After one week, the detectable amount of cells at the depth of 26–50 μm was significantly higher in the modified matrix (MM) than in the non-modified matrix (NM) (p = 0.011). The maximum depth of penetration was 75 μm (NM) and 200 μm (MM). After three weeks, the maximum depth of penetration was 175 μm (NM) and 200 μm (MM). Likewise, at a depth of 0–25 μm the amount of detectable cells was significantly higher in the MM group (p = 0.003). After 14 days, the concentration of DNA was significantly higher in the samples of the MM than in the control group (p = 0.000). Staining of histological sections and labelling with collagen II antibodies showed that a chondrogenic differentiation of cells in the scaffold can occur during in vitro cultivation.Conclusions
Removing the superficial layer is essential to ensuring proper ingrowth of cells within the compressed hydrogel. Compressed hydrogels contribute better to cartilage regeneration after surface modification. 相似文献64.
M. Petri M. Omar H. Horstmann S. Brand C. Krettek 《Archives of orthopaedic and trauma surgery》2013,133(3):351-355
We report the 18-year follow-up of a patient who underwent rotationplasty for severe bone loss and infection after an grade IIIC open fracture of the distal femur. The patient is now 49 years old and fully satisfied with his life. During the follow-up period, he has never had significant physical or psychological problems directly concerning the rotationplasty. The analysis of quality of life using the SF36 questionnaire revealed even higher scores than the normal healthy population in seven out of eight sub-categories. Clinical examination revealed bland soft tissues without hyperkeratosis or other signs of maladaptation. Articular and cutaneous proprioception was intact all over the left leg. The active extension/flexion of the prosthetic knee was 0°–0°–100° and 10°–0°–70° of the ankle joint. Manual testing of motor strength revealed grade five of five for dorsiflexion and plantar flexion of the ankle. Gait patterns including climbing slopes and stairs were close to normal. Examination in sports physiology showed lower maximum power of hip and knee muscles compared to the healthy side, but better muscular endurance. These findings emphasize that rotationplasty can be a good alternative to arthrodesis or amputation in trauma patients providing high satisfaction and activity levels in the long-term follow-up. 相似文献
65.
66.
Susanne Abdulla Stefan Vielhaber Sonja Körner Judith Machts Hans-Jochen Heinze Reinhard Dengler Susanne Petri 《Journal of neurology》2013,260(9):2242-2255
The revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) is a well-established rating instrument to assess the functional status of ALS patients. A recent innovation was the addition of three further items designed to improve its sensitivity at lower levels of physical function (ALSFRS-Extension, ALSFRS-EX). Neither the ALSFRS-R nor the ALSFRS-EX has been validated in German yet. The aim of the present study was the validation of the German version of a self-administered form of the ALSFRS-EX. Seventy-six patients participated in the study. Psychometric analysis included reliability assessment and factorial analysis. To evaluate convergent validity, correlations between ALSFRS-EX items and the MRC score, spasticity, tongue movement, pulmonary function, ALSAQ-40 and Borg dyspnoea scales (upright and supine) were performed. Internal consistency as measured by Cronbach’s alpha (total scale 0.868, subscales 0.690–0.938) and corrected item to total correlations (all above 0.50) was high. Test–retest reliability assessed by Spearman’s rho (0.882–0.972) and Cohen’s Kappa (0.63–0.92) was also high. Principal component analysis with varimax rotation yielded a four-factor solution accounting for approximately 79 % of the variance. Clinical parameters were strongly correlated with respective items and subscores of the ALSFRS-EX (muscle strength 0.568–0.833 p < 0.01; spasticity ?0.236 to ?0.376 p < 0.05; tongue movement 0.437–0.818 p < 0.01; pulmonary function 0.485–0.577 p < 0.01). ALSAQ-40 and Borg score correlated highly with the corresponding ALSFRS-EX items. The German self-report version of the ALSFRS-EX possesses very good psychometric properties similar to the original scale including high internal consistency and test–retest reliability as well as excellent convergent validity. 相似文献
67.
68.
Bravin A Keyriläinen J Fernández M Fiedler S Nemoz C Karjalainen-Lindsberg ML Tenhunen M Virkkunen P Leidenius M von Smitten K Sipilä P Suortti P 《Physics in medicine and biology》2007,52(8):2197-2211
The aim of this study was to introduce high-resolution computed tomography (CT) of breast tumours using the diffraction-enhanced x-ray imaging (DEI) technique and to compare results with radiological and histo-pathological examinations. X-ray CT images of tumour-bearing breast tissue samples were acquired by monochromatic synchrotron radiation (SR). Due to the narrow beam and a large sample-to-detector distance scattering is rejected in the absorption contrast images (SR-CT). Large contrast enhancement is achieved by the use of the DEI-CT method, where the effects of refraction and scatter rejection are analysed by crystal optics. Clinical mammograms and CT images were recorded as reference material for a radiological examination. Three malignant and benign samples were studied in detail. Their radiographs were compared with optical images of stained histological sections. The DEI-CT images map accurately the morphology of the samples, including collagen strands and micro-calcifications of dimensions less than 0.1 mm. Histo-pathological examination and reading of the radiographs were done independently, and the conclusions were in general agreement. High-resolution DEI-CT images show strong contrast and permit visualization of details invisible in clinical radiographs. The radiation dose may be reduced by an order of magnitude without compromising image quality, which would make possible clinical in vivo DEI-CT with future compact SR sources. 相似文献
69.
70.
Sergio Bernardi Serena Bertozzi Ambrogio P. Londero Giuliana Gentile Vito Angione Roberto Petri 《World journal of surgery》2014,38(9):2279-2287