ACL Re-Tear

A number of factors can contribute to the failure of the initial ACL reconstruction. These cases are often complex, with many subtleties that require an expert in complex knee surgery like Dr. Mayo to treat. He will perform a thorough physical examination, analysis of prior surgical details, as well as current imaging scans to determine how to best treat your injury. Some of the things he will assess are:

Incorrect Tunnel Position or Size

During ACL reconstruction, tunnels are drilled into the tibia and femur to accommodate the graft that will serve as your new ACL. If these tunnels are not correctly positioned, it can compromise the biomechanics of the knee joint, leading to graft failure and instability. This may require completely new tunnels be drilled, or in some cases the existing tunnels be filled with bone prior to the revision ACL reconstruction.

Anatomical Factors

Certain anatomical factors can influence the success of ACL reconstruction. For instance, a steep tibial slope (the angle at which your tibia slopes backwards) can increase the strain on your ACL graft, raising the risk of re-tear. If the amount of slope is excessive, you may need a procedure to cut your tibia to change the slope.

Knee Laxity

Increased knee laxity or looseness in the joint can put additional stress on the reconstructed ACL, heightening the risk of failure. It is critical to determine what is causing the increased laxity, such as subtle injuries to other structures in the knee, which may need to be fixed as well.

Need for Lateral Extra-Articular Procedures

In some cases, the initial ACL surgery might have failed to address issues beyond the ACL, like injuries to the lateral (outer) structures of the knee called the posterolateral corner. Failure to address these associated injuries can compromise the success of ACL reconstruction. This is often done in ACL revision surgery to provide an extra piece of stability to prevent a third injury.

Ligamentization of the Graft

“Ligamentization” is the process by which the graft transforms into tissue resembling a natural ligament. If this process is incomplete or delayed, it can lead to graft failure. Sometimes this can happen with no apparent reason, but when it does can lead to a continued loose feeling of the knee.

Early Return to Sport

Returning to sport before your knee has fully recovered can put undue stress on the reconstructed ACL, leading to a re-tear. The graft takes several months to remodel into a ligament that is strong enough to undergo the stresses of competitive sports. If you returned prior to this happening, it may be an increased chance of reinjury. Additionally, getting back prior to you having adequate strength and coordination will put both your knees at risk for injury.

Unforeseeable Causes

Even when the surgery is performed perfectly and all precautions are taken, there are still cases where the ACL can re-tear. This might be due to factors beyond the surgeon’s control, like a high-impact injury.

Before performing a revision ACL surgery, your knee surgeon Dr. Ben Mayo will carry out a thorough evaluation to identify why the initial surgery failed and tailor a surgical plan to address these factors. This might involve:

• Detailed imaging studies to assess the tunnel positions, the tibial slope, and the overall anatomy of your knee
• Evaluating your previous rehabilitation process and your activities since the initial surgery
• Considering whether additional procedures, like a lateral extra-articular tenodesis, are required to enhance the stability of your knee

Revision ACL surgery can be more challenging than the initial reconstruction due to factors like scar tissue, compromised bone quality due to tunnel malposition, and decreased patient morale. However, with meticulous preoperative planning and skilled surgical execution, it’s possible to restore function and stability to your knee.

An ACL re-tear doesn’t mean the end of your athletic journey. While it presents a challenging situation, a thorough evaluation and a carefully planned revision surgery can put you back on the path to recovery. Dr. Ben Mayo’s commitment to individualized care ensures you receive a treatment strategy that’s specifically designed to address your unique needs.