O3234: Juvenile OCD Lesions of the Talar Dome in Surgical and Injured Populations. a Comparison of Return to Baseline, Epidemiology, and Lesion Morphology

Background: Osteochondritis dissecans (OCD) of the talus is the third most frequently affected anatomical location. The exact etiology of these lesions is not completely understood; however, acute traumatic insult or repetitive chronic loading are frequently attributed as causal mechanisms. In juvenile OCD lesions of the talus, assessment of return to baseline activity has not been described based on surgical intervention or a history of injury. Our purpose is to investigate differences in morphology and return to baseline activity between injured vs. non-injured patients, and those treated surgically vs. non-operatively.

Methods: This was a review of an OCD registry at the home institution from 2015-2022. Patients aged 10-18 years with a diagnosis of a talar dome OCD lesion were included. Patients were excluded with inadequate follow up to determine treatment outcomes. Patients without MRI imaging were also excluded. Analysis composed injury vs. no injury and surgical vs. non-operative. Lesion morphology was measured and assessed using coronal and sagittal images on T1 MRI. Consistency of interobserver observations for MRI measurements was evaluated with the intraclass correlation coefficient (ICC).

Results: 68 (59% female) patients met criteria with average age of 12.8 ± 2.6 years. 51 (75%) of patients had a history of injury and 25 (37%) underwent surgery as definitive treatment. Return to baseline did not significantly differ between non-injured and injured patients (p=0.62). Definitive treatment was similar for both injury groups as was injury severity based on Berndt and Harty Classification. More patients with injuries had lesions located medially (n=2, 4% vs. 0%) or anteriorly (n=6, 12% vs. 0%) but these differences were insignificant (p=0.15). Sagittal lesion width was significantly greater in uninjured patients compared to injured patients (14.3 ± 4.6mm vs. 12.1 ± 3.3mm, p=0.04), with lesion area nearing significance as well (median 94.4 range 22.1-205.2 vs. median 78.6 range 17.6-157.1, p=0.056). Time to return to baseline did not significantly differ between surgical and non-operative groups (p=0.15). More surgical patients failed definitive management compared to the no surgery group (n=11, 46% vs. n=5, 29%, p=0.02), however, lesion severity of surgical patients was significantly greater based on Berndt and Harty Classification (p=0.003). All results can be found in Table 1. All ICC values were above 0.80, indicating excellent reliability between observers.

Conclusion: This is the first study to date that assesses return to baseline activity for OCD lesions of the juvenile talar dome. Return to baseline was typically achieved in 5 months but did not differ between patients with history of injury and those with no antecedent injury, nor did it differ between surgical and non-surgical patients. However, lesion size was greater in non-injured patients compared to injured patients, suggesting that repetitive motions may produce microtrauma over a greater area than a single, isolated traumatic event.