Measuring Foot Abduction Brace Wear Time Using a Single 3-Axis Accelerometer

Abstract

The recommended treatment for idiopathic congenital clubfoot deformity involves a series of weekly castings, surgery, and a period of bracing using a foot abduction brace (FAB). Depending on the age of the child, the orthotic should be worn for periods that reduce in duration as the child develops. Compliance is vital to achieve optimal functional outcomes and reduce the likelihood of reoccurrence, deformity, or the need for future surgery. However, compliance is typically monitored by self-reporting, which is time-consuming to implement and lacks accuracy. This study presents a novel method for objectively monitoring FAB wear using a single 3-axis accelerometer. Eleven families mounted an accelerometer on their infant’s FAB for up to seven days. Parents were also given a physical diary that was used to record the daily application and removal of the orthotic in line with their treatment. Both methods produced very similar measurements of wear that visually aligned with the movement measured by the accelerometer. Bland Altman plots showed a −0.55-h bias in the diary measurements and the limits of agreement ranging from −2.96 h to 1.96 h. Furthermore, the Cohens Kappa coefficient for the entire dataset was 0.88, showing a very high level of agreement. The method provides an advantage over existing objective monitoring solutions as it can be easily applied to existing FABs, preventing the need for bespoke monitoring devices. The novel method can facilitate increased research into FAB compliance and help enable FAB monitoring in clinical practice.

Sensors for Human Physical Behaviour Monitoring

“…Compliance with foot abduction brace (FAB) wear is important for the treatment of congenital clubfoot deformity, but self-reporting is time-consuming and inaccurate. Griffiths et al [10] proposed a new method for objectively monitoring FAB wear using a single three-axis accelerometer. The method was tested on 11 families, and the measurements from the accelerometer and the physical diary were very similar, with a high level of agreement.…”

Objective Methods of Monitoring Usage of Orthotic Devices for the Extremities: A Systematic Review

“…The 23 studies that were included in the review included three randomised controlled trials [31][32][33] and 20 observational studies [21,[34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52] (Table 1). Seven studies collected data from healthy participants [34,35,38,39,[42][43][44][45], fifteen studies recruited patients [21,[31][32][33]36,37,41,[46][47][48][49][50][51][52], and one study included data from both healthy and patient participants [40]. The sample size of the included studies ranged from two to 124.…”

“…The sample size of the included studies ranged from two to 124. Five studies used upper limb orthoses [21,34,39,45,46], two used hip orthoses [33,47], and sixteen used lower limb orthoses [31,32,[35][36][37][38][40][41][42][43][44][48][49][50][51][52]. The included studies were conducted in a variety of geographical regions.…”

“…The included studies were conducted in a variety of geographical regions. The majority were conducted in Europe-five in the United Kingdom [32,36,37,42,44], three in the Netherlands [34,40,41], three in Germany [35,38,48], two in Switzerland [21,46], and one in Portugal [39]. Out of the remaining nine studies, seven were conducted in the United States of America [31,45,47,[49][50][51][52], one in China [33], and one in Australia [43].…”

“…Out of the remaining nine studies, seven were conducted in the United States of America [31,45,47,[49][50][51][52], one in China [33], and one in Australia [43]. Studies employed orthoses used for a wide range of medical conditions, including diabetes [32,[40][41][42]48,52], clubfoot [31,37,49,50], postoperative care after shoulder surgery [21,45,46], carpel tunnel syndrome [39], hip fracture prevention [33], hip dysplasia [47], lower limb fracture recovery [35,51], foot drop [44], and spinal cord injury [36]. Three studies did not mention a specific condition but investigated upper limb orthoses for the impairment of the shoulder, arm or hands [34], foot and lower limb disorders [43], and calf muscle unloading [38].…”