Comparison of plantar-pressure distribution and clinical impact of anatomically shaped sandals, off-the-shelf sandals and normal walking shoes in patients with central metatarsalgia
Metatarsalgia is one of the most frequent pathological conditions of the foot and ankle. Numerous studies exist on plantar-pressure characteristics in various types of shoes. However, to the best of our knowledge, plantar-pressure distribution and clinical effects in sandals has not as yet been the the focus of any study.
Twenty-two patients (42 feet) with central metatarsalgia were assessed. Time and distance until symptom occurrence in terms of metatarsalgia were evaluated for normal walking shoes (WS), standard sandals (SS) and anatomically shaped, custom-made sandals with a metatarsal pad (AS). Pain intensity was measured with the visual analogue (VAS), and clinical assessment was performed with the American Orthopaedic Foot and Ankle Society (AOFAS) score for the respective shoes. Additionally, plantar-pressure distribution was assessed with the emed-at platform (Novel GmbH) and the F-scan insole system (Tekscan Inc.), respectively.
The average walking distance until symptoms occurred was 1,894 m [standard deviation (SD) 1,196 m) for WS, 1,812 m (SD 1,079 m) for SS and 3,407 m (SD 1,817 m) for AS (p < 0.01). Mean duration until occurrence of symptoms was 22.3 min (SD 14.9 min) for the WS, 21.8 min (SD 13.4 min) for the SS and 42.0 min (SD 23.0 min) for the AS (p < 0.01). Plantar-pressure parameters were significantly reduced in the forefoot region for the AS compared with the other walking devices.
The results of this study reveal that a modified standard sandal can significantly influence the onset of metatarsalgia, as increased walking time and distance in these patients was observed.