A review of the foot function index and the foot function index – revised

Abstract

BackgroundThe Foot Function Index (FFI) is a self-report, foot-specific instrument measuring pain and disability and has been widely used to measure foot health for over twenty years. A revised FFI (FFI-R) was developed in response to criticism of the FFI. The purpose of this review was to assess the uses of FFI and FFI-R as were reported in medical and surgical literature and address the suggestions found in the literature to improve the metrics of FFI-R.MethodsA systematic literature search of PubMed/Medline and Embase databases from October 1991 through December 2010 comprised the main sources of literature. To enrich the bibliography, the search was extended to BioMedLib and Scopus search engines and manual search methods. Search terms included FFI, FFI scores, FFI-R. Requirements included abstracts/full length articles, English-language publications, and articles containing the term "foot complaints/problems." Articles selected were scrutinized; EBM abstracted data from literature and collected into tables designed for this review. EBM analyzed tables, KJC, JM, RMS reviewed and confirmed table contents. KJC and JM reanalyzed the original database of FFI-R to improve metrics.ResultsSeventy-eight articles qualified for this review, abstracts were compiled into 12 tables. FFI and FFI-R were used in studies of foot and ankle disorders in 4700 people worldwide. FFI Full scale or the Subscales and FFI-R were used as outcome measures in various studies; new instruments were developed based on FFI subscales. FFI Full scale was adapted/translated into other cultures. FFI and FFI-R psychometric properties are reported in this review. Reanalysis of FFI-R subscales' confirmed unidimensionality, and the FFI-R questionnaires' response categories were edited into four responses for ease of use.ConclusionThis review was limited to articles published in English in the past twenty years. FFI is used extensively worldwide; this instrument pioneered a quantifiable measure of foot health, and thus has shifted the paradigm of outcome measure to subjective, patient-centered, valid, reliable and responsive hard data endpoints. Edited FFI-R into four response categories will enhance its user friendliness for measuring foot health.

Adult-Acquired Flatfoot Deformity and Age-Related Differences in Foot and Ankle Kinematics During the Single-Limb Heel-Rise Test

“…The revised Foot Function Index, a valid and reliable self-report measure of foot function, was used to describe functional status. 2 The arch height index (AHI) was calculated for all participants to determine foot posture. Briefly, the AHI was calculated by dividing the height of the dorsum of the foot by the truncated foot length (defined as the length from first metatarsal joint line to the back of the heel).…”

Foot orthoses in the management of chronic subtalar and talo crural joint pain in rheumatoid arthritis

“…Pain is used as a primary outcome measure in many such studies because it is the reason most patients seek treatment and for which practitioners prescribe orthoses [20]. The Foot Function Index (FFI) is indicated for the assessment of treatment outcomes in rheumatology [21] and has been used in a number of trials involving the assessment of orthoses in rheumatoid feet. SooHoo et al [22] performed a study which demonstrated increased responsiveness of foot and ankle specific outcomes tools compared to the SF-36.…”

Effectiveness of Graston Soft Tissue Mobilization Technique with Static Stretching in Subjects with Plantar Fasciitis

“…Foot Function Index Pain Subscale (FFI) for functional disability: 30,31 The FFI was used to obtain information on the impact of the patients' foot pain on their daily activities. It was found to be a valid and reliable scale for measuring foot pain, disability and activity restriction in orthopedic interventional trials and in patients with plantar fascitis.…”