ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION - THE EFFECT OF TIBIAL TUNNEL PLACEMENT ON RANGE OF MOTION

In 111 patients who had anterior cruciate ligament reconstructions, po stoperative radiographic measurements of anterior to posterior and med ial to lateral location of the tibial tunnels were correlated with the final range of motion achieved. In the 25 patients with extension def icits of 100 or more, placement of the tibial tunnel was more anterior (average, anterior 23% of the tibia) than in the remaining 86 patient s with extension deficits of < 10-degrees (average, anterior 29% of ti bia). This difference was statistically significant with P < 0.001. Lo gistic regression analysis revealed that the more anterior the placeme nt of the tibial tunnel, the greater the loss of both flexion (P = 0.0 1) and extension (P = 0.002). In the 21 patients with full extension b ut flexion < 130-degrees, placement of the tibial tunnel tended to be more medial (average, medial 40% of the tibia) than in the 65 patients without flexion deficit (average, medial 45% of the tibia). We conclu de that placement of the tibial tunnel in the ''eccentric,'' anteromed ial position may contribute to the development of flexion and extensio n deficits after anterior cruciate ligament reconstruction.