Comparison of Habitual Versus Recurrent Patellar Dislocation in Children and Adolescents: Differences in Radiological Features

Background: Recurrent patellar dislocation (RPD) and habitual (HPD) in flexion are frequently encountered children adolescents. Purpose: To compare the radiological features of RPD HPD Study Design: Cross-sectional study; Level evidence, 3. Methods: Imaging data were collected from patients aged 9 to 15 years who received surgical treatment for or at a single institution between June 2015 September 2020. The prevalence trochlear dysplasia, tibial tubercle lateralization, lower limb rotational deformity was assessed through hip/knee/ankle computed tomography (CT) using following quantitative indicators: depth index, lateral inclination, sulcus angle, tubercle–trochlear groove (TT-TG) distance, ratio TT-TG distance femoral width, anteversion external rotation angle. morphology trochlea patella graded on knee CT Dejour Wiberg classification. Insall-Salvati index Caton-Deschamps used evaluate height view radiographs. limbs malalignment, mechanical distal angle medial proximal measured weightbearing full-length analyzed compared groups. Results: Enrolled (21 knees) diagnosed with 18 (22 RPD. age first significantly younger group (7.6 ± 3.4 vs 11.2 1.4 years; P = 0.003). Knees had higher proportion type C dysplasia (57.1% 4.5%; < .005) 3 (66.7% 9.1%; .001). There statistically significant differences groups (HPD RPD: 1.1 1.7 2.2 1.5 mm; .039), (170.3° 13.7° 157.3° 16.0°; .007), (1.1 0.2 1.3 0.2; .034), (31.3° 7.8° 38.4° 8.5°; .009). Conclusion: Patients presented poorer development, height, less RPG group.