“Constitutional varus significantly contributes to varus osteoarthritis,” said P-J Vandekerckhove, M.D., a physician with the Department of Vascular Surgery, Sint-Andriesziekenhuis, Tielt, Belgium. “Patients with constitutional varus seem to be more at risk in developing end-stage OA, and this population seems to be a target population for early OA and possible preventive strategies.”
Among 315 patients with unilateral end-stage medial osteoarthritis of the knee, Vandekerckhove and colleagues made a correlation in the coronal plane between medial end-stage OA and the contralateral non-arthritic side.
The researchers performed an analysis of the mechanical lateral distal femoral angle, the medial proximal tibial angle and the joint line conversation angle to determine the knee joint line orientation. Results were compared between the overall population, the male population and the female population.
Vandekerckhove noted patients with more osteoarthritis had a higher rate of constitutional varus. When comparing this result between men and women, results showed a progressive contribution of constitutional varus with more OA among men.
“If you look in men on the osteoarthritic side of more than 6 degrees, up to 60 percent of men had constitutional varus,” Vandekerckhove said. “In patients who had more than 12 degrees of varus, the constitution was even 100 percent.”