BACKGROUND AND OBJECTIVE: Genu varumis a risk factor for the knee osteoarthritis onset. Given the role of exhaustion on the physical condition, understanding physical state fluctuationsin people with genu varum, will give us a good insight for prevention of knee osteoarthritis. The aim of this study was to compare the effect of exhaustive fatigue on body state fluctuations of men with genu varumand normal knees.

METHODS: This quasi-experimentalstudy was performed on 40 healthy male students, including 20 with genu varumand 20 with normal knees (with the average q angle of 25.5±8.0 and 97.8±86.0, respectively). Genu varumdeformitywasmeasured using a caliper and goniometer. Bodyfluctuations were recorded using the force measuring diagram,and Strand modified protocol was used to inducefatigue. 

FINDINGS: There was no significant difference between the two groups after exhaustion in terms of anterior-posterior stability, but there was a significant decrease in medial-lateral stability after exhaustion (genu varum 86.296 mm/sec and normal knee 38.200 mm/sec, pressurecenter shifting,respectively)comparinggenu varumto the normal knee, thesechanges were significant (p=0.04). Interior-exterior stability in both groups,10 minutes after exhaustion was fully recovered.

CONCLUSION: Inside displacementof the line of gravityin genu varumsuffererscan lead to increased volatility of the lateral posture, and since genu varumdeformity causes internal rotation of the leg and turns it into pronation of the subtalar joint inthe weight-bearing position,therefore, these changes in footstructures cancause leg function alterationin control of the internal-external (lateral) balance.