Does the lateral intercondylar ridge disappear in ACL deficient patients?

Abstract

The aim of this study was to determine whether there is a difference in the presence of the lateral intercondylar ridge and the lateral bifurcate ridge between patients with sub-acute and chronic ACL injuries. We hypothesized that the ridges would be present less often with chronic ACL deficiency. Twenty-five patients with a chronic ACL injury were matched for age and gender to 25 patients with a sub-acute ACL injury. The lateral intercondylar ridge and lateral bifurcate ridge were scored as either present, absent, or indeterminate due to insufficient visualization by three blinded observers. The kappa for the three observers was .61 for the lateral intercondylar ridge and .58 for the lateral bifurcate ridge. The lateral intercondylar ridge was present in 88% of the sub-acute patients and 88% of the chronic patients. The lateral bifurcate ridge was present in 48% of the sub-acute and 48% of the chronic patients. This matched-pairs case-control study was unable to show a difference in the presence of the femoral bony ridges between patients with acute and chronic ACL injuries. The authors would suggest looking for the ridges as a landmark of the native ACL insertion site during ACL reconstruction in both acute and chronic ACL injuries.

Fig. 1

Arthroscopic anteromedial portal view of the right knee in 90° of flexion. Both the lateral intercondylar ridge and lateral bifurcate ridge are present

Fig. 2

Arthroscopic anteromedial portal view of the right knee in 90° of flexion. The lateral intercondylar ridge is present, but the lateral bifurcate ridge is absent

Fig. 3

Arthroscopic anteromedial portal view of the right knee in 90° of flexion. Both the lateral intercondylar ridge and lateral bifurcate ridge are absent

Fig. 4

Three-dimensionally reconstructed CT-scan of the right femur of a subject without ACL injury. Both the lateral intercondylar ridge and the lateral bifurcate ridge can be identified