Received 5 March 2011, Accepted 24 March 2011, Available online 23 June 2011. Spontaneous pneumomediastinum is defined as free air within the mediastinum, not associated with trauma. Causes include exercise, drugs, asthma, vomiting, difficult labour and Valsalva maneuvers. Itâs a rare, usually benign and self-limited condition, more prevalent in young males.
A youth bouncing on a trampoline. A trampoline is a device consisting of a piece of taut, strong fabric stretched over a steel frame using many coiled springs. People bounce on trampolines for recreational and competitive purposes.
Here are the steps to follow on how to set up a trampoline: 1  Begin by setting up the legs. 2  Look for long and curved pieces that come with little holes on their ends that are pointing downwards. 3  Join the sections altogether and this could take up a lot of time. It should not be difficult to identify which bars are for the legs. 2  They are short and often come with a 90-degree bend right in the middle. 3  Put them altogether and set aside. 4  Look for long and curved pieces that come with little holes on their ends that are pointing downwards.