Anterior Slope Correction-Flexion Osteotomy in Traumatic Genu Recurvatum

Construct stability in anterior open wedge osteotomy: Assessing 3D-printed polylactic acid wedges against cortical bone

BACKGROUND

This in-vitro biomechanical study aimed to assess whether using a wedge as a gap filler in anterior open wedge osteotomy of the proximal tibia reduces load on the screw-plate construct and to evaluate if a 3D-printed polylactic acid wedge offers similar biomechanical stability like a bone wedge.

METHODS

Twenty-four cadaveric proximal tibiae were randomly assigned to one of three groups: TomoFix plate alone as control group, TomoFix plate with a bone wedge, and TomoFix plate with a 3D-printed polylactic acid wedge. The specimens were subjected to axial loads of 400 N, 800 N, and 1200 N for 1000 cycles. Compression depth and axial stiffness were measured to assess stability.

FINDINGS

There were no significant differences in overall compression depth or axial stiffness between the groups (p > 0.05). At 1200 N, hinge fractures occurred in 6 of 8 specimens in the control group, compared to 0 of 8 in the wedge groups. Both bone and polylactic acid wedges improved construct stability, with the polylactic acid wedge performing comparably to the bone wedge.

INTERPRETATION

Gap fillers, whether bone or polylactic acid wedges, may contribute construct stability in anterior open wedge osteotomy of the proximal tibia. The 3D-printed polylactic acid wedge may be biomechanically comparable to the bone wedge, suggesting its potential as an alternative in clinical applications.

Anterior Open-Wedge Osteotomy to Correct Sagittal and Coronal Malalignment in a Case of Failed High Tibial Osteotomy and Failed Posterior Cruciate Ligament Reconstruction

Anterior open-wedge high tibial osteotomy of the proximal tibia is a reliable surgical procedure to treat genu recurvatum secondary to decreased posterior tibial slope. It is also useful in cases of posterior cruciate ligament (PCL) deficiency, especially after a failed PCL reconstruction procedure as reversal of posterior tibial slope is a common risk factor for failure of PCL reconstruction. In some knee joints, reversed tibial slope may be associated with varus or valgus deformity. We describe correction of reverse posterior slope along with varus deformity, which may result from a poorly performed high tibial osteotomy leading to failure of reconstructed PCL. In our technique, both of the above deformities are corrected simultaneously, thereby addressing the sagittal and coronal malalignments of the knee with one osteotomy.

The Original Technique for Tibial Deflexion Osteotomy During Revision Anterior Cruciate Ligament Reconstruction: Surgical Technique

The original technique for tibial deflexion osteotomy (TDO) was first described by Henri Dejour during the Lyon knee meeting in 1991 to reduce excessive posterior tibial slope during second revision anterior cruciate ligament reconstruction (ACLR). The technique is nowadays increasingly performed during first-revision ACLR in patients at risk for graft retear. This Technical Note describes and updates the original TDO technique.