Bone–Tendon–Bone ACL Plastic

Abstract

The bone–tendon–bone ACL operation with the Diamond TwinS® technology represents a very elegant procedure. There are five diamond tools necessary. As a first step, the patellar bone-graft cylinder is taken out, together with one-third of the patellar tendon and its bony anchorage with part of the tuberositas patellae. Following the outside-in technique, a transverse cylinder is taken out from the lateral femoral condyle, immediately above the lateral collateral ligament. The patellar tendon is thread through the channel with the bone chip from the tuberositas longitudinally once or twice split, and the bone cylinder is carefully hammered into the lateral femoral condyle. Care has been taken so that the fiber layer below glides over the distal rim of the cylindrical defect. With the K-wire guide, one or – for the double bundle procedure – two cylindrical twin defects are ground with the diamond tool through the tibial head. The patellar tendon is carefully thread through the channel and, since the patellar tendon is longer than the original AC ligament, the fiber bundles of the tendon are sandwich-like pressed by the graft. The graft was taken out from the lateral condyle and is now ground flat on one side, while the bone cylinder is hammered until it appears at the level of the tibial plateau. During the whole process, the tendon is pulled distally over the edge of the tibia. The bony anchorage of the tendon is than carefully sutured to the periosteum of the tibia. As a last step, a bone cylinder is gathered from the iliac crest with the largest of the five diamond tools in an orthograde manner for filling the defect in the patella. Care has to be applied not to damage the lateral femoral cutaneous nerve. The result is an absolutely stable ACL. Rehabilitation can start at least 4 weeks after the intervention (Fig. 9.1a–c). In animal experiments, the bone healing of the double bundle plastic could be shown at the 4-week stage (Fig. 2.17a–e).