Classification Description Notes
Pellegrini Stieda Calcification adjacent to the medial femoral condyle Avulsion of the origin of the medial collateral ligament
Reverse Segond Small avulsed fragment from medial tibial plateau Medial Collateral Ligament avulsion with high rates of disruption of the posterior cruciate ligament, MCL and medial meniscus
Fibular Styloid Avulsion Small fragment (mm) superomedial to the styloid


Arcuate complex inserts on the fibular styloid. Implies posterolateral corner instability
Lateral Fibular Head avulsion Larger fragment (1.5-2.5 cm) displaced 2 – 4 cn from fibular head Conjoined tendon inserts on the lateral fibular head.  Implies posterolateral corner instability
Segond fracture Small avulsed fragment from the lateral tibial plateau Lateral Capsular Ligament avulsion. High rates of Anterior Cruciate Ligament and meniscal tears



Gottsegen, C. J., et al. (2008). “Avulsion Fractures of the Knee: Imaging Findings and Clinical Significance.” Radiographics 28(6): 1755-1770.