Tibial Tubercle-Sparing Anterior Closing Wedge Osteotomy With Cross-Screw Fixation to Correct Pathologic Posterior Tibial Slope

Anterior cruciate ligament reconstruction failure remains a commonly seen outcome despite advances in technique and graft options. Recent studies have shown that the declination of the tibial plateau slope in the sagittal plane affects the in situ stress on the anterior cruciate ligament. The native posterior tibial slope has been described to range from 7° to 10°. However, several authors have suggested that a posterior tibial slope >12° should be considered pathologic. Given the recent evidence, our institution has begun performing a tibial tubercle–sparing anterior closing wedge proximal tibial osteotomy with cross screw fixation to decrease sagittal plane tibial slope.
Technique Video Video 1 This video details a tibial tubercle anterior wedge osteotomy to correct a pathologic posterior tibial slope with cross-screw fixation. The patient should be positioned supine on a radiolucent flat top table. The C-arm should be placed on the contralateral side of the operative extremity. Radiolucent triangles are helpful for positioning. The incision is typically 6 to 8 cm beginning at the tibial tubercle and proceeds distally. The osteotomy start point is just distal to the tibial tubercle aiming toward the proximal tibiofibular joint on the lateral radiograph. Breakaway pins and a parallel guide are used to guide the trajectory of the proximal and distal pins. The use of fluoroscopy is recommended to ensure the pins are coplanar on the lateral view. The distal pins are then inserted in a similar fashion to the proximal pins based on preoperative measurements of the necessary osteotomy size. The tips of the distal pins should intersect the proximal pins. The posterior cortex should not be violated. The breakaway pins are then broken off and the pins are used as a cutting guide for the osteotomy. After the bone wedge is removed, the knee should be extended to close the osteotomy gap. K-wires are then used to guide the trajectory of the 4.5mm cannulated crossing screws for fixation. A 3.2-mm drill is used to drill bicortically, followed by a 4.5-mm tap to facilitate screw passage. An anterior trajectory of the screws is recommended.