RELATIONSHIP BETWEEN THE KNEE AND HINDFOOT AXES IN PATIENTS WITH SEVERE KNEE OSTEOARTHRITIS.

OBJECTIVE

To evaluate the correlation between knee axis and hindfoot axis in patients with advanced gonarthrosis, and the association between ankle function and angular deformities.

METHODS

72 patients were enrolled in the study: 66% were women, and mean age was 58.7 years. The anatomical axis of the knee and hindfoot were measured by short knee radiographs and long axial view of the hindfoot.

RESULTS

Among the study group, 79.2% presented varus knee (mean 15º ± 7.69º) and 20.8% valgus (mean 15.9º ± 7.7º). 63.9% had hindfoot varus (mean 8.5º ± 6.07º) and 36.1% valgus (mean 3.9º ± 3.92º) (p < 0.05). The mean value for the American Orthopaedic Foot and Ankle Society (AOFAS) score was 74.26 points, and values were significantly higher among patients with hindfoot varus (p < 0.05). We found no correlation between gender or AOFAS score and knee and hindfoot axes, nor between deformities in the knee and hindfoot axes (p > 0.05). The subgroup genu valgum - hindfoot varus presented a moderate correlation (r = 0.564; p < 0.05).

CONCLUSION

We found no association between the anatomical axes of the knee and hindfoot. Patients with gonarthrosis and hindfoot varus presented a better ankle function. Level of Evidence II, Prognostic Studies - Investigating the Effect of a Patient Characteristic on the Outcome of Disease.