FIGURE 1:

A compromise of the lateral structures is suspected in those patients who have had a prior lateral side procedure, a knee dislocation, or a prior ACL reconstruction procedure that has failed. It is also highly suspected following a PCL tear.

The internal and external rotation (Fig 1) dial tests can be used to assist in the diagnoses of severe lateral rotary instability . The point is that the greater the degree of lateral rotary instability and the more evidence supporting a compromise of the lateral supporting structure, the more likely it is that an "isolated" intra-articular ligament reconstruction will fail.

Therefore, the greater the evidence of severe instability and the greater the evidence of compromise of the lateral structures, the more likely it is that the surgeon should add a lateral stabilizing procedure to the intra-articular procedure.