Introducing Increased Lateral Tibial Height and Decreased Medial Meniscal Bone Angle as Independent Risk Factors for...

Area of Science:

• Orthopedic surgery
• Biomechanics
• Radiology

Background:

• Tibiofemoral rotational malalignment is a known risk factor for recurrent patellar dislocation (RPD).
• While femoral morphology's link to RPD is studied, the association between RPD and tibial plateau/meniscus geometries remains unclear.
• This study investigates tibial and meniscal geometries as potential contributors to RPD.

Purpose of the Study:

• To examine the association between tibial plateau and meniscus geometries and recurrent patellar dislocation (RPD).
• To identify independent anatomical risk factors for adult RPD, beyond traditional measures like TT-TG distance and TFA.
• To evaluate the diagnostic performance of these anatomical parameters in predicting RPD.

Main Methods:

• Retrospective case-control study of 50 adult RPD patients and 50 matched controls.
• Knee MRI scans assessed lateral tibial slope (LTS), medial tibial slope (MTS), lateral tibial height (LTH), medial tibial depth (MTD), medial meniscal bone angle (MMBA), TT-TG distance, and TFA.
• Multivariate logistic regression and ROC analysis identified independent risk factors and assessed predictive ability.

Main Results:

• Significant differences in LTS, LTH, MMBA, MTS-LTS, MTS:LTS ratio, TT-TG distance, and TFA were observed between RPD patients and controls.
• Logistic regression identified LTH (OR 0.409), MMBA (OR 1.456), and TT-TG distance (OR 0.752) as independent RPD risk factors.
• Combined LTH, MMBA, and TT-TG distance showed excellent predictive ability (AUC 0.888, sensitivity 82%, specificity 88%).

Conclusions:

• Decreased lateral tibial slope, increased lateral tibial height, decreased medial meniscal bone angle, and increased slope differences are associated with RPD.
• Increased LTH and decreased MMBA are independent risk factors for adult RPD, even after adjusting for TT-TG distance and TFA.
• Combining LTH, MMBA, and TT-TG distance offers a highly accurate method for predicting adult RPD.