Cobb angle below the fracture. The Cobb angle is the preferred method of measuring post-traumatic kyphosis in a recent meta-analysis of traumatic spine fracture classifications. Scoliosis cases with Cobb angles between 40 and 50 degrees at skeletal maturity progress at an average of 10 to 15 degrees during a normal lifetime. Cobb angles of more than 50 degrees at skeletal maturity progress at about 1 to 2 degrees per year. Those with Cobb angle of more than 60° usually have respiratory complications. Cobb angle The Cobb angle, named after the American orthopedic surgeon John Robert Cobb (1903–1967), was originally used to measure
Six degrees of freedom the interaction with its environment and cannot be commanded. (Pitching motion of a vessel at sea) Transitional type also exists in some vehicles. For example, when the Space Shuttle operates in space, the craft is described as fully-direct-six because its six degrees can be commanded. However, when the Space Shuttle is in the earth's atmosphere for its return, the fully-direct-six degrees are no longer applicable for many technical reasons. "Six degrees of freedom" also refers to movement in video game-play. First-person shooter (FPS) games generally provide five degrees of freedom: forwards/backwards, slide left/right, up/down (jump/crouch/lie), yaw (turn left/right), and pitch