Freddie Fu - ACL Reconstruction Surgery

ACL Reconstruction Surgery

The anterior cruciate ligament (ACL) is responsible for normal knee function including running, cutting, and pivoting. The ACL consists of two functional bundles (the anteromedial (AM) and the posterolateral (PL)) named for their insertion sites on the tibia. They are joined by a septum of connective tissue and function synergistically in providing both anterior-posterior translation and rotational stability to the knee. Wide variation exists from person to person in the size and length of the ACL and insertion sites.

ACL reconstruction is one of the most common procedures in orthropaedic surgery. A.W. Mayo Robson of Leeds, UK first performed the first known ACL reconstruction in the year 1895 on a 41-year old miner. At this time, ACL surgery was an open procedure. In 1938, Palmer first suggested double-bundle ACL reconstruction, which went largely unrecognized until recent times. Thereafter, conversion from open to arthroscopic procedures became standard with the advent of modern technologies.

Regarding the surgical procedure, one of the most challenging technical problems that Dr. Fu and other orthopaedic surgeons encountered in the 1980s was soft tissue fixation to bone. In 1986, Dr. Fu’s Pitt research team along with researchers at Tufts and MIT developed the world’s first bone anchor. Mitek manufactured the first FDA approved bone anchor, and today there are many other bone anchor manufacturers. Over 1.5 million bone anchors are now used on a yearly basis worldwide. Artificial ligament prosthesis was in vogue for ACL reconstruction in the 1980s. His study in 1987 showed the effect of wear particles from artificial ligaments that can be harmful to the joint surface. Because of this study and the complications noted, artificial ligaments are no longer used.

In 1987 Dr. Fu was awarded a Whitaker Foundation Grant for “Glenohumeral Stability: A Dynamic Model”. This led to further joint kinematics studies and to his current collaborations on ACL surgery with Dr. Scott Tashman in the Pitt Biodynamics Lab. Dr. Fu has performed over 6,000 ACL surgeries since 1982 and is a world leader in anatomic reconstruction of the ACL.

Most ACL reconstruction techniques focused solely on single bundle reconstruction. Traditionally, ACL reconstructions were performed non-anatomically by placing the graft outside of the native insertion sites. ACL reconstruction performed non-anatomically may alter the native kinematics of the knee joint has caused concern for the long-term health of the knee joint over time. Recent research has suggested that anatomic double-bundle ACL reconstruction better restores the native kinematics of the knee joint by comparison to traditional, non-anatomical single bundle techniques.

Anatomy forms the foundation for orthopaedic surgery. Surgical reconstruction of the ACL should therefore be performed anatomically. In Pittsburgh, anatomical ACL reconstruction is defined as the functional restoration of the ACL to its native dimensions, collagen orientation, and insertion sites. Collectively, the goal of anatomic ACL is to provide the patient with the best potential for a successful outcome.

Performing anatomical single- or double-bundle ACL reconstruction requires an in-depth understanding of the native ACL anatomy, as well as an understanding of the ‘Double-Bundle Concept.’ In Pittsburgh, there are four fundamental principles for performing anatomic ACL reconstruction: 1) Appreciate the patient’s native anatomy; 2) Tailor each surgery to the patient’s individualized anatomy and needs; 3) Restore the anatomy by placing the tunnels and grafts in the center of the patient’s native ACL footprints; and 4) Restore function by tensioning the grafts to mimic the native ACL as closely as possible.

The clinical outcomes of anatomic single-bundle versus anatomic double-bundle are not yet fully understood. In that regard, Dr. Freddie Fu, along with Principal Investigators Dr. Scott Tashman and Dr. James Irrgang have received a $2.9 million RO1 grant from the National Institutes of Health (NIH) for a randomized controlled level-I clinical trial and are the only institution in the world to be comparing anatomic single to double-bundle ACL reconstruction in this fashion.