Review: femoral tunnel placement for PCL reconstruction in relation to the PCL fibre bundle attachments

Accurate placement of the femoral tunnel position is an important aspect of cruciate ligament reconstruction surgery. However, a wide range of positions have been described in the literature for the femoral tunnels for posterior cruciate ligament (PCL) reconstruction, and there is no consensus regarding the optimal placement. It was hypothesised that some of the prior studies used femoral PCL graft tunnels that were outside of the anatomical attachments. A systematic review and descriptive anatomical study in vitro were undertaken. Fifty articles that described PCL reconstruction since 1917 were reviewed; the description of the femoral tunnel placement was reproducible from only 20 of these. A right, distal femur was disarticulated and the PCL attachment was dissected; the centres of the anterolateral and posteromedial bundles were marked and confirmed to be close to the mean published data. The tunnel positions described in the 20 papers were also marked. The descriptions of 15 of the 20 anterolateral and 4 of the 5 posteromedial bundle tunnel centres were close (within +/- 2 mm deep and +/- 01:00 o'clock) to the anatomical centres of the bundle attachments. Other tunnels were placed either deeper or shallower than the anatomical attachments. The mean positions were: 7 mm from the articular cartilage at 1 o'clock for the anterolateral bundle, and 8 mm from the cartilage at 3 o'clock for the posteromedial bundle, in a right knee. It was concluded that it was not possible to replicate the tunnel positions used in most of the literature because of inadequate descriptions. Most of the usable descriptions of the anterolateral bundle position were close to the anatomical centre, but some tunnels were placed non-anatomically. A reproducible system for description of the femoral tunnel positions should be used.