[Opening-wedge osteotomy of the proximal tibia]

Area of Science:

• Orthopedic surgery
• Biomechanics
• Medical device technology

Background:

• Gonarthrosis and varus deformity are common in middle-aged and elderly populations.
• Accurate correction of the mechanical limb axis is crucial for successful knee joint surgery.
• Traditional osteotomy methods may have limitations in achieving optimal correction and stability.

Purpose of the Study:

• To evaluate the accuracy of correction and short-term outcomes of opening-wedge tibial osteotomy.
• To assess the efficacy of using allograft and a modified Puddu plate fixation.
• To determine the procedure's impact on knee arthritis and varus deformity.

Main Methods:

• Retrospective evaluation of 33 osteotomies in 30 patients (average age 54) with gonarthrosis and varus deformity.
• Preoperative and intraoperative planning based on the limb mechanical axis using X-ray imaging.
• Medial approach tibial osteotomy fixed with allograft and a modified T-plate, aiming for axis intersection at 62% of the lateral articular space.

Main Results:

• Achieved an average mechanical axis intersection at 60.2% of the lateral articular space, with a mean deviation of 2.1 degrees from the planned 62%.
• Lysholm scores improved by an average of 23 points, with 94% of joints showing good outcomes (≥20-point improvement).
• Complications occurred in 6% of joints, including tibial plateau fissure, pseudoarthrosis, and superficial infection.

Conclusions:

• Opening-wedge tibial osteotomy with modified Puddu plate and allograft is an effective and precise method for correcting the lower extremity axis.
• The procedure is simple, associated with few complications, and preserves tibial plateau-diaphysis alignment.
• This technique is not recommended for corrections exceeding 16 degrees; alternative fixation like LCP plates may be considered for larger corrections.