Femoral tunnel placement in Anterior cruciate ligament (ACL)reconstruction

The correct position of the tibial and femoral tunnels for Anterior Cruciate Ligamanet (ACL) reconstruction are generally agreed. However it can be very difficult to acurately reproduce these ideal positions intraoperatively. The correct position of the tibial tunnel is commonly achieved by an outside in aiming device allowing a guide wire to be passed from the proximal tibial cortex into the ACL tibial footprint at the correct trajectory and then the Tibial tunnel drilled with a cannulated drill. The correct placement of the femoral tunnel is more difficult and has been shown to have a larger variability. The current method of femoral tunnel placement is achieved by passing a guide wire either through the tibial tunnel (transtibial technique) already created or through an anteromedial porthole in an inside out manner. Alternatives to these methods are being developed to improve the reproducibility of correct femoral tunnel placement. A new technique where by an outside in method for placement of the femoral tunnel has been developed to circumvent some of the problems seen with the inside out method. This involves using a tibial aiming device and then passing a specially engineered guide wire called a Flip Cutter (trademark) which when in the correct position can deploy a cutting edge to drill the femoral tunnel in a retrograde fashion. It is thought that this technique will allow more consistent, accurate placement of the femoral tunnel which will correspond in a better functioning graft and more stable knee. The exposure will occour only once during the operation.