ACL reconstruction: Effect of bone dowel on tibial tunnel enlargement

PurposeTo evaluate prospectively if the impaction of a bone dowel in the tibial tunnel prevents the tunnels from enlarging beyond their original diameter.MethodsSeventeen patients underwent arthroscopically assisted ACL reconstruction with hamstring autologous graft. All patients underwent CT of the knee on the day of surgery, at 3 months and 12 months post-op.ResultsOn the day of surgery, the median cross-sectional areas of the tunnels were 77.0 and 79.0 mm2, respectively at 15 mm and 20 mm from the tip of the posterior wall of the tunnel. At 3 months, the median cross-sectional areas of the tunnels were 70.0 and 65.0 mm2, at 15 mm and 20 mm. At 12 months post-op, the median cross-sectional areas of the tunnels were 69.0 and 69.0 mm2. The median enlargement of the tunnels between 3 months and 12 months post-op was 0.0 mm2 at 15 mm and − 2.0 mm2 at 20 mm.ConclusionsThe impaction of an autologous bone dowel in the tibial tunnel during hamstring ACL reconstruction keeps the tunnels from enlarging beyond their original diameter, and there is no further enlargement of the tunnels after 3 months post-op.