ABSTRACT
Femoral cross-pin fixation in anterior cruciate ligament (ACL) reconstruction has
a potential for neurovascular injury, thus a “safe zone” must be defined for safe
pin passage with this technique. In this anatomic study, femoral-sided, arthroscopic-assisted
ACL reconstruction using the TransFix system (Arthrex, Naples, Fla) was performed
on five fresh extended thigh and lower leg cadavers. Using a goniometer, five cross-pin
guidewires were sequentially drilled at 0°, −20°, −40°, +20°, and +40°, using the
parallel to floor line as 0°. Negative was defined as starting the pin more posteriorly,
and positive was defined as starting the pin more anteriorly. Distance from the pin
to the peroneal nerve, saphenous nerve, and femoral artery was measured after pin
placement, and measurements were averaged. The peroneal nerve was at minimal risk
with average distance to the guide pin of 1.87, 2.13, 2.45, 2.74, and 3.05 cm at −40°,
−20°, 0°, +20°, and +40°, respectively. The saphenous nerve was an average distance
of 2.19, 1.98, 1.41, 1.42, and 1.29 at −40°, −20°, 0°, +20°, and +40°, respectively.
The femoral artery was an average distance of 1.81, 1.51, 0.78, 0.46, and 0.08 cm
at −40°, −20°, 0°, +20°, and +40°, respectively. Based on this anatomical study, the
absolute neurovascular safe zone during cross-pin guidewire placement is from +20°
(0° parallel to floor line) and −40° (lowering guide more posterior).
