Patella extremely intense pain and swelling. The patella can be tracked back into the groove with an extension of the knee, and therefore sometimes returns into the proper position on its own. A "patella alta" is a high-riding (superiorly aligned) patella. An attenuated patella alta is an unusually small patella that develops out of and above the joint. A "patella baja" is a low-riding patella. A long-standing patella baja may result in extensor dysfunction. The kneecap is prone to injury because of its particularly exposed location, and fractures of the patella commonly occur as a consequence of direct trauma onto the
Composition of the human body viewed on an atomic and molecular scale as shown in this article. The estimated gross molecular contents of a typical 20-micrometre human cell is as follows: Body composition can also be expressed in terms of various types of material, such as: There are many species of bacteria and other microorganisms that live on or inside the healthy human body. In fact, 90% of the cells in (or on) a human body are microbes, by number (much less by mass or volume). Some of these symbionts are necessary for our health. Those that neither help nor harm humans are called commensal