A bone screw including a housing including a threaded opening defined between first and second legs extending from a base portion of the housing, and a threaded closure member configured to be threaded into the threaded opening of the housing between the first and second legs to secure a connecting member in a channel of the housing. The threaded closure member includes a first thread and a second thread intertwined with the first thread, and the threaded opening includes a first discontinuous thread and a second discontinuous thread intertwined with the first discontinuous thread.