Introduction: Each year millions of people are treated for hip, knee or foot surgery which require rehabilitation programs that typically involve limited or controlled weight bearing on an affected limb. Weight bearing reduces edema & facilitate rapid rehabilitation.

Current weight-bearing instruction protocols involve non-quantitative guidelines, based on the patient’s amount of discomfort while walking or subjective perception. However, the interpretation of these instructions is inaccurate and subjective, and varies among clinicians and patients.

New biofeedback technology concepts are beginning to be implemented in the rehabilitation process. The Smart-Step system is a new weight bearing monitoring system that assists clinicians and physical therapists to accurately assess, train and monitor patients’ weight bearing capabilities.

Purpose: To assess the effectiveness of the SmartStep system in guiding weight bearing restrictions, and to assess the effectiveness of the SmartStep system as a tool to reeducate full weight bearing.

Material and Methods: 8 Patients in the Orthopedic rehabilitation department & 5 patients in the orthopedic physiotherapy out-patient clinic, post orthopedic surgery with FWB instructions were randomly divided into Study & Control groups.

During treatment, the patients were trained by the PT in FWB according to the instruction of the surgeon. Data of age and body weight was collected from all patients. Patients in both study groups used the SmartStep System. This system consists of an in-shoe inflatable insole, pressure sensors and a control unit for data storage. The control unit provides also an audio signal whenever the patient was bearing body weight at a recommended and pre-calibrated level.

Results: The mean age and body weight were 62±12 years and 76±15 kg in the study group and 65±15 years and 70±13 kg in the control group.

Data obtained in both groups (in kg) during the pre-test and during the gait tests was converted into percentage of the patients BW. The means of the differences between the pre-test results and the gait test results in both groups were 9 + 6.7% and 1.5 + 6% in the study and control group, respectably (p=0.0002).

Conclusions: The new Smartstep system was proved to be a useful tool in assisting gait rehabilitation since its biofeedback system enhances and improves weight bearing over the affected limb in cases where FWB is recommended.

Introduction: The regulation of balance during upright standing involves continuous muscular activity, associated with body sway. In single stance standing, the base of support is narrower compared to double stance, resulting in an increased body sway and emphasizing the role of individual muscles in regulating the sway motion. In this study, we investigated the effect of Tibialis Anterior (TA) fatigue on body sway during standing on one leg on ten able-bodied subjects.

Methods: Foot ground reaction forces, goniometry of the ankle joint, and EMG of the TA were all measured simultaneously in two tests. Each test lasted 30 sec. During which the subjects were required to stand as still as possible with their dominant leg on a forceplate and the contralateral knee flexed upward at 90 deg approximately, and their hands resting on their waists. The tests were separated by a 4 min isotonic fatiguing effort of the TA, indicated by a significant decrease of the mean power frequency (MPF).

Results: The EGM root mean square (RMS) started off at 45% MVC but, towards the end of the effort, significantly increased to 52% MVC, the latter determined in non-fatigue condition. Compared to the non-fatigue state, the following significant (p< 0.05) sway changes took place in the fatigue state: force RMS increased from 2.61 to 3.90 N and from 3.77 to 5.01 N in the mediolateral (ML) and vertical directions, respectively. The center of pressure (CoP)

RMS in the ML direction increased from 0.57 to 0.68 cm. The EMG RMS in the TA increased from 4.15 to 5.58 and the MPF decreased from 107.6 to 96.7 Hz in the fatigued state.

Discussion: An interesting finding was revealed by comparing the variations of the ankle angle to those of the center of pressure in the anterior-posterior direction taking place during standing. During the non-fatigue test the CoP moved gradually posteriorly, while the goniometer indicated an ankle change towards dorsiflexion. These obviously two opposing trends necessitate compensatory angular adjustments at the knee and/or hip joints. However, during the fatigue test, the posterior excursion of the CoP was accompanied by a consistent change in the ankle, towards plantar flexion. This seems to suggest that in the fatigue state the redundancy of the musculoskeletal system is reduced, increasing the degree of correction between ankle angle and CoP.