Genotype-Specific Postural Control Deficits in Hemophilia A: Insights from Center of Pressure Analysis Beyond Radiographic Arthropathy

Hemophilia is an X-linked inherited bleeding disorder characterized by joint hemorrhages and progressive arthropathy. While mutation type is known to influence disease severity, its impact on postural balance strategies has remained unclear. This cross-sectional study investigated the relationship between gene mutation type and postural control in hemophilia A patient using center of pressure (CoP) analysis and radiographic joint assessment with the Pettersson score. Thirty-five participants were divided into an INV group (intron 22 or intron 1 inversion of the F8 gene) and a NonINV group (other mutations). While the Pettersson scores and traditional time-domain CoP parameters (sway area, velocity) were comparable between groups, frequency domain analysis revealed a significant difference. INV group exhibited significantly higher energy content above 2 Hz in the anteroposterior direction compared to NonINV group. This genotype-specific spectral signature emerged despite comparable radiographic arthropathy and conventional CoP metrics, suggesting that frequency-domain CoP analysis can uncover subclinical postural adaptations in hemophilia A. These findings highlight the need for targeted proprioceptive training in this specific subpopulation to prevent subclinical instability and potential falls.