The Effect of Anti-Gravity Treadmill on Balance in Acute Phase of Post-Operative Knee Rehabilitation

Abstract

Background: An anti-gravity treadmill has been used in orthopedic and neurological rehabilitation. However, little literature on its use in post-operative knee rehabilitation is available. Objectives: The purpose of this investigation was to study an effect of anti-gravity treadmill on balance in an early phase of post-operative knee rehabilitation. Methods: Forty-nine patients who underwent knee surgery participated in this study (study design: cohort study; level of evidence: level II). At one week post-operatively, each patient was tested for timed single leg stance (SLS) on surgical knee on a floor. Patients were placed onto either AlterG group (AG) or control group (CG) after the test based on their pain level. The patients in AG underwent a balance exercise on AlterG, with the pressure adjusted to a pain-free or minimal pain level, once a day at least 5 days a week. Those in CG underwent their balance exercise on a floor in the same manner. All patients were tested again for SLS at 2 week post-operatively. The lengths of SLS were recorded and analyzed. Results: The lengths of SLS were 38.8 seconds and 19.9 seconds for CG and AG, respectively, at 1 week post-operatively. They improved to 50.5 seconds (CG) and 35.0 seconds (AG) at 2 week post-operatively. There was statistically significant between-group difference at both 1 week and 2 week post-operatively. However, there was no significant between-group difference in improvement from week 1 to week 2. Conclusions: A use of anti-gravity treadmill may have a positive effect on balance in an acute phase of post-operative knee recovery in patients who had an increased level of pain during full weight-bearing immediately after knee operation.