Arthroscopy joint by a portal on the outer border of the patella. It is not clear if these examinations were of deceased or of living patients. Pioneering work began as early as the 1920s with the work of Eugen Bircher. He published several papers in the 1920s about his use of arthroscopy of the knee for diagnostic purposes. After diagnosing torn tissue, he used open surgery to remove or repair the damaged tissue. Initially, he used an electric Jacobaeus thoracolaparoscope for his diagnostic procedures, which produced a dim view of the joint. Later, he developed a double-contrast approach to improve visibility.
Effect of spaceflight on the human body Effect of spaceflight on the human body Venturing into the environment of space can have negative effects on the human body. Significant adverse effects of long-term weightlessness include muscle atrophy and deterioration of the skeleton (spaceflight osteopenia). Other significant effects include a slowing of cardiovascular system functions, decreased production of red blood cells, balance disorders, eyesight disorders and a weakening of the immune system. Additional symptoms include fluid redistribution (causing the "moon-face" appearance typical in pictures of astronauts experiencing weightlessness), loss of body mass, nasal congestion, sleep disturbance, and excess flatulence. The engineering problems associated with leaving Earth and developing