Anatomical Components Associated With Increased Tibial Tuberosity-Trochlear Groove Distance

Area of Science:

• Orthopedic surgery
• Biomechanics
• Anatomy

Background:

• Increased tibial tuberosity-trochlear groove (TT-TG) distance is a significant indicator for medial tibial tubercle transfer in managing lateral patellar dislocation (LPD).
• Changes in TT-TG distance result from various anatomical factors.

Purpose of the Study:

• To identify anatomical components contributing to an increased TT-TG distance.
• To quantify the contribution of each component to pinpoint the most influential factor.

Main Methods:

• A case-control study involving 80 patients with recurrent LPD and 80 matched controls.
• Comparison of TT-TG distance and related anatomical parameters: tibial tubercle lateralization (TTL), trochlear groove medialization, femoral anteversion, tibiofemoral rotation (TFR), tibial torsion, and mechanical axis deviation (MAD).
• Statistical analysis including Pearson correlation and stepwise multivariable linear regression to identify predictors of TT-TG distance.

Main Results:

• Significant differences between LPD and control groups in TT-TG distance, TTL, TFR, and MAD (P < .001).
• TT-TG distance positively correlated with TTL (r = 0.376), femoral anteversion (r = 0.166), TFR (r = 0.574), and MAD (r = 0.415).
• Stepwise analysis identified higher TTL, excessive knee external rotation (TFR), and knee valgus (MAD) as significant predictors of increased TT-TG distance, with TFR being the most prominent.

Conclusions:

• Tibial tubercle lateralization (TTL), tibiofemoral rotation (TFR), and mechanical axis deviation (MAD) are key anatomical contributors to increased TT-TG distance.
• Tibiofemoral rotation (TFR) emerged as the most prominent component influencing TT-TG distance.
• Understanding these associations can aid in surgical planning for LPD.