I had a total hip replacement almost 10 years ago. I evidently have a customized lateral flare cementless femoral stem. I understand the cementless part, but what does it mean to have a lateral flare?

Over the years it's been shown that the shape and design of the joint replacement implant plays a big role in the success or failure of the surgery. At first, hip joint implants had more of a straight stem. The stability of the implant depended on the support of the inside edge of the bone.

This concept has been changed to a lateral flare femoral stem. The outer or lateral side of the implant flares out making one side wider and more angled. This brings the part of the implant that rests on the bone up higher supported by an additional column of bone.

The extra lateral contact area creates a wider base of support. Studies show this design gives a more physiologic or natural distribution of the load during standing and walking activities. This feature allows for a more even loading pattern on both sides of the upper part of the femur.