Relationship between the pivot shift and the configuration of the lateral tibial plateau.

Twenty patients with a chronic anterior cruciate ligament tear were studied. First they were interviewed on the preoperative history of unexpected giving way (pivot shift), then they were tested for clinical pivot shift sign, and last, the configuration of the lateral tibial plateau was studied using magnetic resonance imaging. A connection could be noticed between the history of instability symptoms and the pivot shift sign at clinical examination (P less than 0.001). Interestingly, there was also a link between the instability history and the configuration of the lateral tibial plateau (P = 0.0021), and, further, between the clinical pivot shift sign and the configuration of the lateral tibial plateau (P = 0.0002). The variation in the shape of the convexity of the lateral tibial plateau seems to be associated with the symptoms and prognosis of the patients with rupture of the anterior cruciate ligament.