Pretibial cyst formation after anterior cruciate ligament surgery with soft tissue autografts

Four cases of subcutaneous pretibial ganglion, with direct communication to the tibial tunnel after autologous reconstruction of the anterior cruciate ligament (ACL) with hamstrings or iliotibial band, are reported. Tibial graft fixation was with a staple in three cases, and with a screw and soft tissue washer in one. The average time to ganglion development was 44 months, and all occurred more than 2 years after ACL surgery. At the time of cyst development, no patient had subjective or objective knee instability. No patient had evidence of tibial tunnel enlargement. All ganglion communicated with the tibial tunnel. This communication was shown with magnetic resonance imaging in two cases, which showed the origin at the joint. Three patients elected to have the ganglion removed; in each of these there was a direct communication with the tibial tunnel. Additionally, hardware was removed in all cases, and local autologous bone grafting of the tibial tunnel aperture was done in two. Minimum follow-up after surgical excision was 2 years, without evidence of recurrence.