Evaluation of the relationship between trochlear and patellar morphology and patellar chondromalacia with magnetic resonance imaging.

It was aimed to investigate the relationship between magnetic resonance imaging (MRI) measurements of trochlear and patellar morphology and grade 3-4 patellar chondromalacia. Grade 3-4 patellar chondromalacia group, and an age- and sex-matched control group with normal patellar joint cartilage were comprised. For trochlear morphology evaluation in MRI; sulcus angle, trochlear angle, lateral trochlear inclination angle and medial trochlear inclination angle were measured. For patellar morphology evaluation; patella trochlear ratio, insall-salvati ratio, modified Insall- Salvati ratio and Blackburne-Peel ratio were measured. Obtained measurements were statistically analyzed according to demographic characteristics. One hundred and twenty-five patients with chondromalacia and 125 controls participated. The sulcus angle and the trochlear angle were significantly higher in the patellar chondromalacia group (p<0.05). The lateral trochlear inclination angle was significantly less in the patellar chondromalacia group (p=0.011). There was no significant difference between the groups in terms of medial trochlear inclination angle (p=0.520). There was no significant difference between the groups in terms of patella-trochlear ratio (p=0.617). Insall-Salvati ratio was significantly higher in the patellar chondromalacia group (p=0.003). Modified Insall-Salvati ratio was significantly lower in the patellar chondromalacia group (p=0.001). The rate of Blackburne-Peel was significantly higher in the patellar chondromalacia group (p=0.004). Measurements of sulcus angle, trochlear angle, lateral trochlear inclination angle, Insall-Salvati ratio, modified Insall-Salvati ratio, Blackburne-Peel ratio have diagnostic value for grade 3-4 chondromalacia.