Low back pain as the presenting sign in a patient with primary extradural melanoma of the thoracic spine - A metastatic disease 17 Years after complete surgical resection

Primary spinal melanomas are extremely rare lesions. In 1906, Hirschberg reported the first primary spinal melanoma, and since then only 40 new cases have been reported. A 47-year-old man was admitted suffering from low back pain, fatigue and loss of body weight persisting for three months. He had a 17-year-old history of an operated primary spinal melanoma from T7-T9, which had remained stable for these 17 years. Routine laboratory findings and clinical symptoms aroused suspicion of a metastatic disease. Multislice computed tomography and magnetic resonance imaging revealed stage-IV melanoma with thoracic, abdominal and skeletal metastases without the recurrence of the primary process. Transiliac crest core bone biopsy confirmed the diagnosis of metastatic melanoma. It is important to know that in all cases of back ore skeletal pain and unexplained weight loss, malignancy must always be considered in the differential diagnosis, especially in the subjects with a positive medical history. Patients who have back, skeletal, or joint pain that is unresponsive to a few weeks of conservative treatment or have known risk factors with or without serious etiology, are candidates for imaging studies. The present case demonstrates that complete surgical resection alone may result in a favourable outcome, but regular medical follow-up for an extended period, with the purpose of an early detection of a metastatic disease, is highly recommended

Teacher professional knowledge and classroom management: on the relation of general pedagogical knowledge (GPK) and classroom management expertise (CME)

Due to the need for measurement instruments that allow an investigation of teachers' situational cognition and thus go beyond the limited scope of classical paper-and-pencil-tests, we ask how a specific video-based measurement of teachers' classroom management expertise can provide additional information when compared with an established paper-and-pencil-test that broadly covers mathematics teachers' general pedagogical knowledge. For this, we apply the general pedagogical knowledge test previously developed in the Teacher Education and Development Study-Mathematics (TEDS-M) comprising knowledge of structuring lessons ('structure'); motivating students and managing the classroom ('motivation/classroom management'); dealing with heterogeneous learning groups ('adaptivity'); and assessing students ('assessment'). Using test data of 188 novice teachers, advanced beginners, and expert teachers, we raise questions regarding the two tests' (1) structural relations, (2) expert-novice differences, and (3) predictive validity. Findings: (1a) classroom management expertise can be empirically separated from general pedagogical knowledge, although the two constructs are positively inter-correlated (medium effect size), (1b) classroom management expertise is more highly correlated with pedagogical knowledge of classroom management than with pedagogical knowledge of 'adaptivity', 'structure', and 'assessment', (1c) classroom management expertise is more highly correlated with procedural pedagogical knowledge (cognitive demand 'generate') than with declarative pedagogical knowledge (cognitive demands 'recall' and 'understand/analyze'), (2) novice teachers as well as advanced beginners are outperformed by expert teachers, and (3) classroom management expertise, compared with general pedagogical knowledge, is a stronger predictor for instructional quality aspects of classroom management as rated by students