Lower Limb Deformity and Gait Deviations in Patients with X-Linked Hypophosphatemia

In a recent report, Gabriel T. Mindler and colleagues were able to show, for the first time to their knowledge, that lower limb deformity (such as mechanical axis deviation, lateral bending, and malrotation), body mass index (BMI), and X-linked hypophosphatemia (XLH)-specific features, such as enthesopathies, “negatively affected gait quality among adolescents and adults with XLH.” This conclusion was based on a retrospective assessment of skeletal deformities, osteoarthritis, pseudofractures, and enthesopathies in radiographs of lower limbs.

The study, published in Frontiers in Endocrinology, included laboratory examination and gait analysis results from a total of 29 patients with confirmed XLH, which was then compared to a control cohort of 76 healthy reference individuals.

According to the study, patients with XLH had a lower gait quality when compared to healthy controls (gait deviation index [GDI] = 65.9% ± 16.2). Furthermore, about 48.3% of the study’s participants had a greater lateral trunk lean at presentation, “commonly referred to as waddling gait,” the authors supplied. Additionally, a higher BMI and lower limb mechanical axis deviation were both associated with lower gait scores and greater lateral trunk lean. Finally, patients with radiologic signs of enthesopathies had a lower GDI.

Ultimately, the study’s authors concluded that “patients with XLH require a comprehensive and adequate treatment in a multidisciplinary setting,” and further suggested that “assessment of lower limb deformities and gait deviations should be implemented in future diagnostic and therapeutic studies to address this important aspect of disease burden in XLH patients.”