[Subtuberosity anterior closing wedge osteotomy to correct the increased posterior slope of the tibial plateau].

Objective: Reduction of increased reclination of the tibial plateau (posterior slope) to improve the anterior stability of the knee joint.

Indications: Increased posterior reclination of the tibial plateau greater than 12° in combination with recurrent instability after anterior cruciate ligament (ACL) reconstruction.

Contraindications: Hyperextension of more than 15° (relative).

Surgical Technique: Anterior skin incision approximately 8-10 cm above the tibial tuberosity. Insertion of two converging guidewires directly below the patellar tendon ending obliquely in the area of the posterior cruciate ligament (PCL) insertion. Control of the wire position with the image intensifier core. Oscillating saw osteotomy. Removal of the wedge and closure of the osteotomy. Osteosynthesis with interfragmentary screw and medial angle-stable plate.

Postoperative Management: Partial load with 10-20 kg for 2 weeks, then step by step increase in load. Mobility: free.

Results: To date we have operated on 36 patients with recurrent instability after ACL reconstruction (20 men, 16 women, average age 34.4 years) in the manner described in this article. In 25 cases, enlarged bone tunnels were filled with allogeneic bone at the same time. The posterior slope of the tibial plateau could be reduced from an average of 14.5° to 8.8°. In 28 cases another ACL reconstruction was performed after an interval of 4-12 months. The Lysholm score significantly increased from 76.3 points to 89.2 points.