A compliance real-time monitoring system for the management of the brace usage in adolescent idiopathic scoliosis patients: a pilot study

Adolescent idiopathic scoliosis (AIS) is a three-dimensional deformity of the spine and it affects 1 ~ 3% of children between 10 and 16 years of age [1]. Brace treatment has been widely used for growing patients with curves larger than 25°, but smaller than 45° ~ 50°. And it has emerged as the only proven method of non-operative treatment [2].

The outcome of brace treatment depends on many factors such as age, gender, bone maturity, curve pattern, curve magnitude, and compliance [3]. Among them, compliance is a significant one for patients to achieve a satisfactory outcome of brace treatment. In order to better understand the role of compliance in brace treatment success, the comprehensiveness and accuracy of the measuring methods must be guaranteed.

Historically, patient compliance was measured subjectively by conducting questionnaires, reviewing a patient diary, or simply asking patients and their parents [4‐8]. These subjective measurements were arguably inaccurate and could result in mistaken conclusions about brace treatment effectiveness [9]. Therefore, electronic devices were developed to measure medication compliance objectively. The electronic solution can be divided into three categories: temperature-based systems [2, 10‐18], force-based systems [19‐24], and force and temperature-combined systems [9]. A temperature-based system, with its temperature sensors, can record the brace wearing time (quantity) of the patients accurately, but cannot measure the wearing tightness (quality). In comparison, a force-based system or a force and temperature-combined system, with their respective monitors, can record both the wearing quantity and the wearing quality.

Some scholars have already applied compliance temperature/force monitors to the brace treatment of AIS patients in clinical practice [2, 9, 10, 13‐18, 20‐22]. The monitored data was firstly stored in the electronic device and then downloaded at the patients’ routine clinical visits (range 3 ~ 6 months). In this way, both clinicians and patients/parents could know how much time and how well the orthosis is worn after the analysis of the acquired data. However, the data only revealed the quantity and/or quality of brace usage during the past period before the patients returned to the clinic, so that patients were not able to make improvements in time. Therefore, it is better to find a way to measure patient compliance in real time, so as to improve AIS patients’ compliance with orthoses.

Mobile health (mHealth) is the practice of medical and public health supported by mobile devices such as phones, tablets, personal digital assistance, and wireless infrastructure [25]. The development of mHealth and popularization of smartphones enable patients to use mobile medical devices to collect their health data in real time, deliver and share the data with their doctors remotely, and receive feedback from the clinicians in time [26]. Some mHealth applications have been studied and applied to spine surgery patients in recent years [26‐28]. However, to our knowledge, few studies had implemented an mHealth-based intervention to manage the brace usage in AIS patients. Hence, the objective of this study is to describe and evaluate a compliance real-time monitoring system of the brace usage in AIS patients.

This study was approved by the ethics committee of West China Hospital of Sichuan University and informed consent was obtained from the patients and their parents. All methods were carried out in accordance with relevant guidelines and regulations.

A total of 30 AIS patients were enrolled in this study. Among them, there was one patient who found her data logger detached from the brace and broken, the other patient could not upload the data from her data logger to the smartphone. Therefore, 28 patients (5 males and 23 females) were included in the final analysis. The mean patient age was 12.4 ± 1.5 years (range: 10 ~ 15 years). The follow-up period of all patients was 6 months. The mean baseline brace force was 1.23 ± 0.28 N (range: 0.82 ~ 1.95 N). The mean measured force was 0.79 ± 0.29 N (range: 0.25 ~ 1.60 N). The mean quality compliance was 64.8 ± 22.2% (range: 29.2 ~ 127.7%). The prescribed time of all patients was 23 h. The mean measured time was 14.1 ± 2.9 h (range: 6.8 ~ 18.7 h). The mean quantity compliance was 61.3 ± 12.6% (range: 29.8 ~ 81.6%).

Details of measured force, quality compliance, measured time, and quantity compliance for each patient were listed in Table 1. The quality compliance during the first 3 months of treatment was significantly lower than the latter 3 months of treatment (49.1% vs. 80.5%, P<0.05). Similarly, the quantity compliance of the first 3 months was significantly less than that of the latter 3 months (52.3% vs. 70.3%, P<0.05).

In this study, 96.4% (27/28) patients are satisfied with the use of the monitoring system, among whom 21.4% (6/28) are very satisfied and 75.0% (21/28) are somewhat satisfied. There was only one patient who was somewhat dissatisfied with the system.

The measuring method of compliance is a key element in the accuracy of reported compliance. Previous studies used subjective ways such as questionnaires and diaries to measure the time that the brace has been worn during daily activities [4‐8]. But the validity of such compliance data was questionable because patients may often overestimate their brace wearing time [10, 30]. With advances in technology, electronic devices were utilized to measure compliance. The most common of such devices were temperature and pressure/force sensors. The temperature sensors were proved to be effective to monitor wearing time [2, 10‐18], but they could not measure the level of wearing tightness. Nicholson et al. [10] reported that the mean temperature at the skin-brace interface was 32.8 ± 1.6 °C. So, another limitation of the temperature sensors is that their accuracy may be affected when the ambient temperature reaches 30 ~ 40 °C level. In this study, the thin film force sensor was chosen to monitor the patient compliance. The primary advantage of this sensor is its ability to monitor wearing quantity and quality simultaneously. In addition, this small force sensor can be installed at any position of the brace surface and is easy to mount/dismount without destructing the corrective mechanism of the brace.

The influence of compliance is related to many factors. Takemitsu et al. [31] found that age correlated with compliance and younger patients showed higher compliance. Rahimi et al. [3] indicated that patient compliance might be improved if the orthotists would provide the opportunity for patients to choose the preferred appearance and construction. Nicholson et al. [10] considered that psychological feature could alter the amount of orthosis wearing hours. Daytime and nighttime wearing patterns are another two factors that could impact patient compliance, but which one is better is still controversial [2, 9, 10, 21, 23].

If these influential factors with brace treatment were considered, the patient compliance would be improved. Miller et al. [16] designed a randomized clinical trial to evaluate the direct effect of electronic monitoring (temperature probe) on brace-wearing compliance and found that patients, who were aware that their compliance was being monitored, would be more compliant than those who were unaware of such monitoring. A similar relation was found in the study by Karol et al. [15]. In this study, all patients and their parents were told at the beginning of the treatment that sensors embedded into patients’ brace would monitor their wearing time and wearing tightness of the brace. In addition, clinicians provided suggestions for patients/parents according to the actual downloaded compliance data at least once every 3 months since the time when the brace was prescribed. The mean measured time (14.1 ± 2.9 h) and the mean quality compliance (64.8 ± 22.2%) were greater than that in previous studies [16, 32]. The increased compliance seen in this study can be largely attributed to the timely and frequent communication between clinicians and patients/parents. With the aid of the compliance real-time monitoring system, patients or their parents could consult clinicians whenever they had any question about the treatment and receive the professional and individualized guidance from clinicians in time. Additionally, both the quality and quantity compliance during the first 3 months of treatment was significantly lower than the latter 3 months. For one thing, the first 3 months might be a transition period as the patients were getting accustomed to their new braces. For another, the feedback provided by clinicians based on the data of the first 3 months might amplify the Hawthorne effect [16] on these enrolled patients.

Patients and their parents’ attitudes towards electronic monitors are significant to the application and popularization of these monitors. Donzelli et al. [14] investigated the attitudes of 364 parents and patients with regards to the use of temperature sensors. They also found that the mean rate of parents stating a completely or at least partially positive attitude was 94.0% while it was 85.6% among patients. In the present study, the percentage of patients who were very satisfied or somewhat satisfied reaches 96.4%. Such a high satisfaction would be attributed to the following reasons more specifically: (1) patients and their parents could review the historical compliance data and real-time wearing tightness whenever they want, (2) patients and their patients could receive regular professional and individualized advice from clinicians according to the patients’ data, (3) patients or their parents could consult clinicians about the questions they met during the patient’s brace treatment without restrictions of time and place, and (4) minimize the need for in-person visits to the clinic, thus maximize the reduction of patients’ financial and time expense, especially for patients from remote areas.

The main strength of this study is the establishment of an integrated compliance real-time monitoring system that has proved to be efficient for the brace usage management in AIS patients. This system not only allows patients to perform active self-evaluation of their treatment, receive regular individualized guidance, and consult their clinicians online, but also help clinicians to make necessary adjustments timely or find better solutions for diagnosis and treatment. To date, the most commonly prescribed wearing time is 23 h per day, which is generally based on the past clinical experience of clinicians. The optimal wearing tightness of brace treatment is still unknown (being too tight can cause pain and pressure ulcers, while being too loose will compromise therapeutic efficacy). As data are accumulated over time through the compliance real-time monitoring system, it is believed that the ideal values of the wearing time and applied force will be worked out via cognitive computing, predictive analytics, artificial intelligence, and other advanced technologies.

Some limitations still exist. Since this pilot study mainly aimed to validate the feasibility and practicality of the system in question, it did not expect to see dramatic clinical changes in the brace treatment of AIS patients after the system was adopted. That is why only a small sample size of 30 patients was chosen and a short follow-up time of 6 months was investigated. However, this is not enough if the goal of the study is to provide a strong support for a large-scale application of the system in the future. In addition to the present study, at least three tasks will be fulfilled further: an analysis of the clinical and radiographic outcomes of patients who have received the treatment; necessary modifications and upgrading of the system after this initial test (to name a few, more force sensors will be added to improve the accuracy of the monitor, the data collected by the monitor can be uploaded to the cloud system synchronously without extra help from patients or their parents as long as the internet is connected, and the system will automatically send a reminder to patients or their parents on the ideal values of the wearing time and applied force that they can adjust to, based on large-scale computing); evaluations of the updated system with a larger number of patients, control groups and longer follow-up.

The compliance real-time monitoring system, without evaluating the clinical and radiographic outcomes for now, has already shown some feasibility and effectiveness for the management of the brace usage in AIS patients. This system, as a useful tool for online patient management and patient-clinician communication, would be potentially employed on a large scale in future for clinicians to improve the compliance and satisfaction of AIS patients who have received the brace treatment.