Most surgeons would agree that any concern a patient has is an important worry to solve. Understanding the process of what is happening to you is all part of patient education. So whenever possible, take your courage in hand and ask what’s on your heart and mind.
As you have just experienced, patients who have a total hip replacement can end up having a second or revision surgery because of a failed implant. Occasionally the revision surgery fails. And in rare cases, patients end up with three or four attempts at a successful hip replacement. Fortunately no one loses a limb because of these problems.
The surgeon does his or her best to find the right implant that will work for you. Bone loss from repeatedly inserting and removing implants can be a problem. The operated leg can end up being shorter than the uninvolved limb. Such a leg length discrepancy alters your biomechanics and gait (walking) pattern and can create additional pain.
To combat this problem, surgeons and manufacturers of joint replacements have worked together to design a modular implant. These implants are somewhat adustable to offset leg length differences from bone loss. This feature allows for improved joint movement that mimics normal motion more closely than previous less adjustable implants.
The modular units (like a modular home) come with interchangeable parts that can be assembled and adjusted at the time of the surgery. A prosthetic femoral stem component is made up of a body, a neck, and a stem. The height of the neck is adjustable (high or low) and the stem can be made longer or shorter according to what the patient needs. For patients with bone loss, the newer revision implants don’t require cement to hold them in place. Instead, the surgeon can use hardware or fixation devices such as pins, wires, and screws to secure them.
The separate pieces of the modular implant are held together with a modular connection and that connector has a taper junction and an engaged-fit junction. Femoral stem fractures are a problem at these modular junctions. Implant manufacturers have worked with surgeons to find a design strong enough to withstand the forces at the intersection between two component parts.
If you are not a good candidate for the modular implant (or any other appropriate implant for your situation), the surgeon could fuse the hip. Hip fusion stops all motion at the joint so although there are limitations in movement and function, the limb is saved. So don’t be afraid to ask your surgeon just what are your options and the most likely plan of care that best suits your goals, dreams, and desires.