For decades surgeons and prosthetists have been working in tandem to create a more comfortable prosthetic experience for amputees. In the 1920's a Hungarian surgeon developed a groundbreaking procedure which has revolutionized the way many perform below knee amputations. For those who have the ability to plan the time and date of their amputation, or if one is in need of a revision surgery, discussing the benefits of the Ertl (bone bridge) with your surgeon is worthwhile.
In the intact human leg, the tibia and fibula bones connect at the ankle. This connection not only completes the "bone circuit" but also increases the stability and strength of the structure. With most bk amputations, the tibia and the fibula bones are severed. A skin flap is brought over the bones, creating the residual limb. The tibia and fibula bones are left unconnected.
With the standard below knee amputation, the tibia and fibula bones are structurally weakened. Over time and with prosthetic stresses, the bones can rub creating pain, discomfort and fractures. This is commonly referred to as "chopsticking." Although certainly not impossible, it is difficult and painful for individuals with this type of amputation to bear weight directly on the bottom of the stump.
With an amputation done using the Ertl procedure, the tibia and fibula are joined by a piece of bone screwed into place. The bones eventually fuse giving the resulting residual limb a wider base. The wider base makes it easier for the amputee to bear weight. Amputees who have undergone the Ertl procedure do not experience as many difficulties maintaining a comfortable prosthetic fit. The structural integrity of the amputated limb is nearly restored to its pre-amputated strength because the bone circuit is reconnected.
The bone bridge procedure has some initial drawbacks. First, it requires more surgical skill to perform than the basic amputation and not all surgeons are competent with the procedure. Because of the increased complexity, the patient is in the operating room and under anesthesia for a longer period of time.
In our experience, amputees who have undergone an Ertl procedure have fewer prosthetic issues. Because volume fluctuations are minimal, the prosthetic fit is more consistent and the amputee is less reliant upon socks to obtain a comfortable socket. The bone bridge is able to bear weight, affording the individual the ability to put direct pressure onto the bottom of the limb. If you have questions about the Ertl procedure, we encourage you to talk with your surgeon to determine if it is appropriate.