Video Presented by: Jiayi Luo, MD | Chuan Ye, MD | Long Yang, MD | Zhanyu Wu, MD | Qiang Zou, MD | Siwei Luo, MD

This technique can be applied in high tibial osteotomy (HTO) procedures to facilitate the incorporation of subchondral microfracture drilling via the primary surgical incision. The anatomical landmark used for localization is the junction between the tibial tuberosity and the patellar tendon, which is readily exposed through the standard HTO approach.

The optimal timing for transtibial microfracture drilling is immediately after insertion of the osteotomy guide pins, which does not significantly prolong the operative time. In fact, once the surgeon is familiar with the technique, the procedure may even shorten the overall operative duration by eliminating the need for separate arthroscopic portals or additional exposure.

Our anatomical studies identified the ideal entry point for the microfracture targeting K-wire to be on the medial border of the junction between the tibial tuberosity and the patellar tendon. Preoperative imaging can be used to estimate this point, typically located 2.0–2.5 cm medial to the edge of the patellar tendon. A 2.0 mm Kirschner wire is inserted at an angle of 15–20 degrees, ensuring that the first fluoroscopic confirmation avoids penetration of the posterior tibial cortex. Once optimal positioning is confirmed, the wire is advanced to penetrate both the tibial and femoral subchondral bone.

Subsequent microfracture drilling is performed using a custom-designed guide device developed by our team, ensuring consistent angle, spacing, and depth of penetration.

Indications for this technique include patients with advanced medial compartment knee osteoarthritis undergoing medial open-wedge HTO. The transtibial microfracture approach promotes cartilage regeneration and facilitates intraosseous decompression, thereby contributing to pain relief and biological joint preservation.

By utilizing this innovative method, medial tibial subchondral microfracture drilling can be performed safely and efficiently through the standard HTO incision, without the need for additional arthroscopic intervention.