Journal of Pediatric Orthopaedics - 2026-08-11 - Journal Article
Is D-Dimer Associated With Disease Severity and Contralateral Slip Risk in Slipped Capital Femoral Epiphysis?
Kurk MB, Albayrak K, Aydin A, Kayis G, Akpinar E
Topics
Key Takeaway
D-dimer levels were significantly higher in SCFE patients versus obese and healthy controls (P<0.001) and correlated with contralateral slip development, improving contralateral slip prediction AUC from 0.80 to 0.87 when added to Southwick angle difference and MOBS, though this AUC gain was not statistically significant (P=0.18).
Summary Depth
Choose how much analysis to show on this article page.
Summary
This single-center retrospective cohort study evaluated whether serum D-dimer levels correlate with SCFE severity and contralateral slip risk in 25 unilateral SCFE patients compared to obese and healthy controls. D-dimer was significantly elevated in SCFE versus both control groups, was higher in unstable and acute-on-chronic cases, and positively correlated with CRP and NLR while negatively correlating with MOBS and interhip Southwick angle difference. Adding D-dimer to a model combining age, MOBS, and Southwick angle difference improved AUC from 0.80 to 0.87, but this improvement did not reach statistical significance (DeLong test P=0.18).
Key Limitation
The sample size of 25 patients is insufficient to power multivariable logistic regression or ROC comparisons, making all predictive model conclusions exploratory and potentially spurious.
Original Abstract
BACKGROUND
To evaluate D-dimer levels in patients with slipped capital femoral epiphysis (SCFE), to investigate their association with disease severity and the development of contralateral slip, and to assess their contribution to existing predictive models.
METHODS
In this single-center retrospective cohort study, 25 patients with unilateral SCFE diagnosed between January 2020 and April 2024 were included. The control group consisted of age- and sex-matched obese individuals and healthy subjects with normal body mass index (BMI). Clinical variables (age, sex, BMI, stability according to the Loder classification, and chronicity); laboratory parameters [complete blood count, neutrophil-to-lymphocyte ratio (NLR), inflammatory markers including C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), and coagulation parameters including prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, and D-dimer]; and radiographic measurements [Southwick angle, interhip angle difference, posterior sloping angle (PSA), and modified Oxford bone score (MOBS)] were analyzed. Subgroup analyses based on stability and chronicity were performed, and correlations between D-dimer levels and clinical, laboratory, and radiographic parameters were assessed. Multivariable logistic regression models were constructed to predict contralateral slip, and model performance was evaluated using receiver operating characteristic (ROC) curve analysis.
RESULTS
D-dimer levels were significantly higher in the SCFE group compared with both obese and healthy control groups (P<0.001). D-dimer showed positive correlations with CRP and NLR and negative correlations with the MOBS and the interhip Southwick angle difference. Higher D-dimer levels were observed in unstable and acute-on-chronic cases (P<0.001). During a mean follow-up of 24 months, patients who developed contralateral slip had significantly higher D-dimer levels (P=0.002). The addition of Southwick angle difference to a baseline model including age and MOBS increased the AUC from 0.73 to 0.80, while further inclusion of D-dimer improved the AUC to 0.87. However, the increase in AUC after addition of D-dimer was not statistically significant according to the paired DeLong test (P=0.18).
CONCLUSION
D-dimer levels are associated with disease severity and the risk of contralateral slip in SCFE. Incorporation of D-dimer into established clinical and radiographic parameters improved predictive model performance. These findings support the role of inflammatory and microvascular processes in the pathogenesis of SCFE and suggest that D-dimer may serve as a useful adjunct biomarker for risk stratification.
LEVELS OF EVIDENCE
Level III-retrospective cohort study.