The reproducibility of radiographic measurement of lateral meniscus horn position

Purpose: The objective of our investigation was to evaluate whether it is possible to locate and reproduce the tibial insertion areas of the anterior and posterior horns of the lateral meniscus on preoperative radiographs. Methods: In 20 tibia heads, we prepared anterior and posterior horn insertions and marked their circumference with radiopaque steel balls of 1.6 mm in diameter. Standardized anteroposterior and lateral radiographs were made. On these radiographs, different landmarks were defined, their distances measured (tibial width and depth, distance from lateral tibia border to meniscus insertion midpoint, distance from anterior tibia border to meniscus insertion midpoint, distance from anterior and lateral tibia border to lateral intercondylar spine), and ratios determined. Results: The anterior horn midpoint is located at 45.1% +/- 1.3% of tibial width and 41.9% +/- 3.2% of fibial depth, and the posterior horn midpoint is located at 49.8% +/- 1.9% of tibial width and 72.1% +/- 2.3% of tibial depth. The statistical analysis of these measures showed a precise and constant positioning of the lateral meniscus insertions on the tibia plateau. We also found constant topographic relations to the lateral intercondylar spine. Conclusions: Anterior and posterior lateral meniscus horn insertions can be determined on radiographs with a high precision and reproducibility. Clinical Relevance: We have developed a technique for precise radiographic fibial horn determination in lateral meniscus transplantation.