Footprint measurement methods for the assessment and classification of foot types in subjects with Down syndrome: a systematic review

Background: Musculoskeletal disorders, especially in the feet, are common in people with Down syndrome (DS). Evaluation of podiatric footprints is important to prevent and manage orthopedic symptoms. The reliability of a wide variety of footprint measurement methods has been evaluated in healthy people, but few studies have considered the specific morphotype features of the feet in subjects with DS. The aim of this systematic review was to identify the podometric measurement tools used to typologically classify the footprints in the population with DS. Methods: The following electronic databases were searched for studies describing footprint measurement tools to assess and classify the foot types in patients with DS published from inception to December 2020: PubMed, Web of Science, CINAHL, and Scopus. Articles were initially searched by screening titles and abstracts. Potentially relevant studies were then further screened by reviewing full texts. Studies that met the inclusion criteria were included in the review. Results: Of the 122 articles identified by the search strategy, 14 full texts were retained to assess for eligibility, of which 11 studies met the inclusion criteria and were included. All the studies used footprint measurement methods to classify the foot types in subjects with DS, but only two studies assessed the reliability of those methods for the population with DS. The footprint measurement tools identified were a podoscope, a pressure-sensitive mat, a PressureStat^TM carbon paper, and a 3D scanner. The Arch Index was the most common footprint measurement analyzed (seven studies). Two studies used the “gold standard” indexes that include Hernández-Corvo Index, Chippaux-Smirak Index, Staheli Index, and Clarke Angle to measure footprints. Conclusions: There is a need to determine the reliability and validity of the footprint measurement methods used for clinical classification of the foot types in subjects with DS. This can contribute to an early diagnosis of foot abnormalities that would help to reduce mobility impairments, improving the quality of life of patients with DS.