副木是一種低溫成形的塑膠醫材，放入攝氏60度C 的熱水中約數分鐘便可軟化，此時副木可直接在人體上成型，而當其溫度低於50度C或室溫時，便可以定型，定型後的副木如同石膏般堅硬，有良好的支撐效果，比石膏輕巧許多，而且方便拆卸，有利換藥及清潔皮膚，而副木本身是塑膠成品，可以以冷水清洗，保持衛生。由於副木有良好的延展性及可塑性，可以完全依個人身體部位曲線成型，故穿戴起來會比較合身舒適。此外副木再加熱後，便可以不斷修改，非常經濟實惠。

The Orthopedic splint is a kind of plastic medical material formed at low temperature. It can be softened by placing it in hot water of 60°C for a few minutes. At this time, the orthopedic splint can be directly formed on the human body. When its temperature is lower than 50°C or room temperature, after cooling, the orthopedic splint is as hard as cast, and has a excellent supporting effect, moreover, the weight is much lighter than cast, and is easy to disassemble, which is beneficial to dressing or cleaning. As the orthopedic splint is a plastic product, which can be washed with cold water. Because of the good formability, it can be completely shaped according to the body, so it will be more comfortable to wear. In addition, after reheated, it can be continuously modified, which is very economical.