LAUSR

PurposeTo investigate the effects of early patellar dislocation on the tibial tubercle location.MethodsSixty knees from 30 healthy 1-month-old New Zealand white rabbits were randomly divided into two groups of 30 knees each. Group A (control group) comprised the left knees, which underwent no surgical procedures. Group B comprised the right knees, which underwent patellar dislocation surgery. Computed tomography (flexion 0°) was performed preoperatively and 6 months post-operatively. Measurements included the tibial tuberosity–trochlear groove distance (TT–TG) and tibial tubercle lateralization.ResultsNo significant difference in the TT–TG or tibial tubercle lateralization was found between the two groups preoperatively. Six months post-operatively, however, the mean TT–TG in Group A (no patellar dislocation) and Group B (patellar dislocation) was 1.0 ± 0.4 and 3.0 ± 0.7 mm, respectively (p < 0.05). The mean tibial tubercle lateralization also showed a significant difference between Groups A and B at 6 months post-operatively (0.5 ± 0.1 and 0.6 ± 0.0, respectively; p < 0.05).ConclusionsEarly patellar dislocation can lead to tibial tubercle lateralization and an increased TT–TG. Clinically, early intervention for adolescent patients with patellar dislocation will be important.Level of evidenceProspective comparative study, Level II.