fig4 b illustrates a top view of locking screw 400 looking down at the top side of head 402 as illustrated in fig4 a locking screw 400 generally includes a body 401 and a generally conical head 402 that tapers into a generally cylindrical shaft 404 ending at a tip 406 screw 400 further includes two generally continuous threads 1001 and 1002 intertwined in a double helix format threads 1001 and 1002 extend over the majority of locking screw 400 from tip 406 along the length of shaft 404 onto head 402 in particular embodiments screw 400 may be formed by carving threads 1001 and 1002 out of a blank this may enable head 402 to be low profile so as to minimize the profile thickness of the plate screw interface when screw 400 is engaged within a fixation plate 500 as shown in fig5 each double helix thread 1001 and 1002 may generally be defined by a leading flank 410 411 a trailing flank 412 413 and a crest 414 415 connecting the outer edge of respective leading flank 410 411 to the corresponding outer edge of trailing flank 412 413 each thread includes a root 416 417 it will be understood by one skilled in the art that since threads 1001 and 1002 are overlapping and helical in nature the descriptions previously provided with respect to the characteristics.