Knee instability before and after high tibial osteotomy

Area of Science:

• Orthopedic Surgery
• Biomechanics
• Knee Joint Research

Background:

• Knee joint instability and varus/valgus deviation are key factors in arthrotic knee conditions.
• Accurate measurement of knee joint stability is crucial for surgical planning.

Purpose of the Study:

• To evaluate knee joint instability and varus/valgus deviation in arthrotic knees compared to normal knees.
• To assess the impact of high tibial osteotomy on knee instability and patient outcomes.
• To determine optimal surgical strategies for varus malalignment correction.

Main Methods:

• Utilized three-point measurement technique (Edholm et al. 1976, 1977) to assess knee joint stability.
• Compared instability and varus/valgus deviation in arthrotic knees versus normal knees.
• Analyzed changes in instability following high tibial osteotomy for varus malalignment.

Main Results:

• Arthrotic knees showed no significant difference in instability compared to normal knees.
• Significant differences in varus/valgus deviation were observed between arthrotic and normal knees.
• High tibial osteotomy for varus malalignment led to a significant increase in knee instability.
• Instability increases exceeding 2 degrees were linked to significantly poorer subjective surgical outcomes.

Conclusions:

• Shortening lateral stabilizing structures of the knee joint is recommended during high tibial osteotomy for varus malalignment.
• Preoperative instability thresholds for successful outcomes require further investigation.