# A Systematic Review of Insole Sensor Technology: Recent Studies and Future Directions
## 4 Insole Sensor Technology
### Applications
#### 4.7.1 Rehabilitation  
In rehabilitation, electronic systems are highly effective for monitoring and analysis, as they exhibit greater sensitivity to changes in patient improvement than traditional medical observation. Insole sensor systems designed for these applications are especially user-friendly since they do not require controlled environments and are often cost-effective for implementation outside clinical settings. Moreover, these compact and convenient sensors offer practical alternative to larger and more heavy equipment such as force plates, motion capture systems, and instrumented treadmills [16].  
The main recovery application is the rehabilitation of the limb, especially in post-surgery phase. In postoperative recovery the wearables can provide comprehensive monitoring capabilities [1]. Real-time gait detection using wearable sensors offers an unprecedented approach for delivering clinical interventions to individuals with gait impairments (stiffness, balance issues, unsteady and staggering walking, shuffling steps, difficulty starting and stopping movement, and other behaviors). A normal gait pattern indicates repeated gait cycles, and an abnormal gait pattern may suggest a neuron disease, a lower limb motor disfunction, and injuries [3]. The optimal combination of sensors and gait detection methodologies enables the creation of assistive devices that can significantly enhance the effectiveness of rehabilitation and improve the quality of life for people with ambulatory deficits [33]. To this matter the development of algorithms have the ability and capacity to extract data of interest, such as CoP, contact time, and cadence, parameters that are commonly associated to development of diseases [5].  
To demonstrate the importance of WT in rehabilitation, in a study [25], there was utilized seven IMU sensors and a pair of plantar pressure insoles to collect walking data from both healthy individuals and patients with hemiplegia. Adding to the previous study, the works of [PERSON] et al. [5] and [PERSON] et al. [3] present several examples of how important it is to gather and analyze various metrics such as pressure, joint angular velocity, stride interval, swing interval, stance interval of both feet, and acceleration of subjects with and without diseases to monitoring the status and conditions. Diseases such as Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis is referred in the previous work. [PERSON] et al. [1] also confirm that limb and movement disorders allow motion sensors to be used, such as postural instability (including falls) of patients with [PERSON]'s disease. This kind of equipment can be helpful for diabetics by monitoring foot pressure, temperature, humidity alterations of foot ulcers in daily life [3].  
In conclusion, we can say with some certainty that the more data, the better. However, in rehabilitation, there are many diseases and pathologies to consider; therefore, it is very difficult to collect data, and there is no basis for comparison to analyze and make assumptions. [PERSON] et al. [5] have noted the following: \"To extract the effect of a specific disease on patients' gait from multiple diseases fusion, it is necessary to track the gait of different patients for a long time and continuously analyze the gait of the same patient.\"