O3261: Incidence of tibial tubercle fractures in patients with and without Osgood-Schlatter disease

Background: Patients with Osgood-Schlatter disease (OSD) may be at increased risk of tibial tubercle fractures due to the underlying weakness of the tibial tubercle apophysis relative to the patellar tendon as a result of repetitive microtrauma. Prior literature estimates that approximately 23% of patients with tibial tubercle fractures have a history of OSD, however, there remains a paucity of robust literature that analyzes the relationship between OSD and tibial tubercle fractures. The purpose of this study is to analyze the incidence of tibial tubercle fractures in patients with and without Osgood-Schlatter disease. We hypothesized that the incidence of tibial tubercle fractures would be higher in those with a previous diagnosis of OSD relative to those without a diagnosis of OSD.

Methods: A retrospective cohort analysis of the PearlDiver (PearlDiver Technologies, Colorado Springs, CO) database was performed by querying all patients diagnosed with Osgood-Schlatter disease between January 1, 2010 and April 30, 2021. An experimental cohort of 4,222 patients was captured using using International Classification of Diseases, Ninth Revision (ICD-9), Tenth Revision (ICD-10) billing codes, and age as inclusion/exclusion criteria. This cohort was compared against a randomly generated cohort of 990,109 patients without a diagnosis of OSD. Student’s t¬-test and ¬chi-square analyses were used to compare the demographics and comorbidities between the experimental and control cohorts. Multivariable logistic regressions, controlling for residual differences in age, sex, and obesity, were used to compare rates of tibial tubercle fractures, which were calculated at 1-, 3-, 6-, and 12-months after the diagnosis of OSD was made.

Results: Patients with a recent history of OSD were found to have higher rates of tibial tubercle fractures at all measured time points (p < 0.001). The incidence of tibial tubercle fractures in the OSD group was 852.7 cases per 100,000 person-years compared to 0.61 cases per 100,000 person-years in the control group (p < 0.001). Obesity was also associated with an increased risk of sustaining a tibial tubercle fracture within these patient populations.

Conclusion: We report a significantly higher incidence of tibial tubercle fractures among patients with OSD compared to controls. This increase was most significant at three months following OSD diagnosis, however, held true for all measured time points. Additionally, patients with obesity were noted to have increased incidence of tibial tubercle fractures regardless of an OSD diagnosis. Our findings regarding the increased incidence of tibial tubercle fractures in patients with OSD supports prior assumptions that have previously been unsubstantiated. This information may be useful to counsel patients and their families on the risk of tibial tubercle fracture after being diagnosed with OSD and may influence clinicians’ recommendations regarding follow-up for patients with OSD.