The iHAND MPS-I project builds on decades of structured follow-up at the Wilhelmina Children’s Hospital through the Sylvia Tóth Center. This has resulted in the availability of an extensive amount of clinical and imaging data. Using this unique cohort, we are conducting a series of retrospective studies to better understand upper extremity disorders in children with Mucopolysaccharidosis type I (MPS-I).

As part of this work, we examine the prevalence, surgical outcomes, recurrence rates, and histopathological findings of carpal tunnel syndrome and trigger fingers. These analyses provide more accurate data on the timing of development, identify factors that influence disease progression, and support surgical planning and follow-up strategies.

In addition, we study the extensive archive of systematically collected upper extremity X-rays to investigate skeletal growth and deformities. This includes establishing MPS-I-specific reference values for bone age, cortical thickness, and bone dimensions, as well as analyzing bowing of the radius and ulna and deformities of the wrist. Together, these efforts will generate an age-specific reference values overview for bone growth in MPS-I and a severity classification for skeletal deformities that can be applied in both clinical care and research.

By integrating these findings, the iHAND MPS-I project will deliver the largest systematic overview of upper extremity pathology in MPS-I to date, advancing our ability to predict disease progression and improve care for affected children.