Splinters are foreign bodies which are fully or partially embedded in your skin. Also splinter can be defined as a fragment of a larger object, especially wood, or a foreign body which can penetrate or it is purposely injected into your body. This foreign body must be lodged inside the tissue to be considered as a splinter. Splinters are usually wood, but plastic material, glass and metal can be also considered as splinters. There are some cases when splinters have to be removed by medical professionals, especially when splinters are lodged under a fingernail or toenail or they are deeply embedded in them. Most people who have splinters are able to remove them without medical help. They are usually found when they penetrate the skin and this is usually happening in the foot or hand. Almost always, even fully embedded foreign bodies can have a unique sensation for you. Also it is known that splinters are full of germs. If splinters are not remove or if they do not work their way out themselves, then this can cause an infection. You should avoid rubbing hands on wooden surfaces such as toys, railings, playground equipment, outdoor furniture and picnic tables. You should wear shoes on docks, boardwalks and decks and when wading in water. You should clear of bushes and plants with spikes or thorns. You should wear shoes or slippers after glass breaks on the floor. There are rare cases when people can become infected with splinters from some unusual sources. It is said that the most common foreign bodies which are contracted by people fall into 2 official classes – nonbiological and biological splinters. In biological splinters are included wood, teeth, fish spines and bone. In the nonbiological splinters are included plastic, pencil graphite, fishhooks, aluminum, metal and glass. The most common cases of exotic foreign bodies include stingray spines, insect stings, sea urchins and even grenade shrapnel.
Here are some signs and symptoms which you can feel or notice when you have splinters :
- In the most cases, splinter is fairly obvious. Person, who has splinter, feels a pain and he has a sense that a foreign body is embedded in his skin. Also in many cases the individual can see the splinter under or in the skin. 
- Also the affected person can have only a small flow of blood or no bleeding at all.
- The affected person may or not may be able to feel the splinter or a tip of it.
- There are some cases when splinter is not noticed until the affected person develops infections. When the infection develops, then the area becomes tender, warm, swollen and red.
- A small speck or line under the skin, usually on the hands or feet
- Pain at the location of the splinter
- A feeling that something is stuck under the skin
In the most cases, splinters do not need care of a health care provide. You need to call a health care provider if the splinter is deep in the skin or the wound is bleeding heavily or you cannot remove the entire splinter. Also, if the splinter is under the toenail or fingernail, then talk with your health care provider. 
Here are can mentions some causes of splinters:
- When you are handling an object this can cause a small portion to dislodge as you are applying friction to some object and these examples can include falling and sliding on wooden floors, metalworking and woodworking. 
- Also it is known that the protective thorns of plants can cause splinters to lodge in your skin while you are gardening. 
- Also butchers can end up with a small splinter of bone penetrating into your skin. 
- Your foot can be injured when you slide forward or you step on a foreign body (some examples of this action can include stepping on shards of glass or walking on a rough wooden deck or boardwalk). 
Types of foreign bodies: There are many types of foreign bodies which can stuck into your skin such as
- Plastic FBs
- Pencil lead (graphite)
- Fishhooks: May have a barbed point that makes removal difficult
- Fiberglass spicules
- Metallic FBs: tacks, pins, sewing needles, nails, BBs and bullets
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