Background: During anterior cruciate ligament reconstruction, proper
femoral tunnel placement is important. The purpose of the present study was to
characterize the osseous anatomy of the femoral intercondylar notch.
Methods: We studied the morphology of the femoral intercondylar
notch in 200 human femora from skeletally mature donors, with specific
attention being paid to the morphology of the ridge on the lateral wall of the
intercondylar notch and the posterolateral rim of the intercondylar notch. The
distances from the posterolateral rim of the intercondylar notch to the
lateral intercondylar ridge and from the posterolateral rim of the
intercondylar notch to the inlet of the intercondylar notch (notch depth) were
measured at the nine, ten, and eleven o'clock positions for right knees and at
the one, two and three o'clock positions for left knees.
Results: The lateral intercondylar ridge was present in 194 femora
and absent in six. The mean distance from the posterolateral rim of the
intercondylar notch to the lateral intercondylar ridge was 9.0, 11.0, and 12.7
mm at the nine, ten, and eleven o'clock positions in right knees and the one,
two, and three o'clock positions in left knees, respectively. We observed
three different types of morphology of the posterolateral rim of the
intercondylar notch. The morphology of the posterolateral rim of the
intercondylar notch was distinct in 183 of 200 specimens. A distinct, straight
border (type 1) was seen in 175 femora (87.5%); a distinct, V-shaped border
(type 2) was seen in eight (4%); and an indistinct border (type 3) was seen in
seventeen (8.5%).
Conclusions: The morphology of the femoral intercondylar notch
varies little. Occasionally, the posterolateral rim of the intercondylar notch
is not well-defined. In these knees, accurate placement of commercial femoral
tunnel aiming guides may be difficult.
Clinical Relevance: This improved knowledge of the morphology of the
intercondylar notch may assist the surgeon in placing the femoral tunnel in
the proper location when performing anterior cruciate ligament
reconstruction.