e/Polyaxial screw

Information
has gloss	eng: A polyaxial screw is used for connecting vertebrae to rods in spinal surgery. It is essentially a screw whose spherical head is enclosed on a housing, which allows the screw a range of motion along several different axes relative to the housing. The ball joint allows the surgeon some flexibility in placing the screws.
lexicalization	eng: polyaxial screw
instance of	c/Implants