US Patent 7758648 Stabilized, adjustable expandable implant and method

An expandable medical implant with a length along its expandable dimension that has a first tubular member with a connection end including a first set of protrusions and an opposite skeletal interface end. Also, the expandable implant has a second tubular member with a connection end including a second set of protrusions configured to engage with the connection end of the first tubular member. The second tubular member including an opposite end opposite from the connection end. The first set of protrusions includes a flank with a negative flank angle such that the flank is positively loaded when the implant is compressively loaded along its length.