Prolonged infection at the tibial bone tunnel after anterior cruciate ligament reconstruction.

A 24-year-old man with severe atopic dermatitis underwent anterior cruciate ligament (ACL) reconstruction of the right knee seven years earlier but developed a surgical site infection. The infection did not heal after removal of the metal implants, and a fistula eventually developed. This condition was left untreated for six years before he was referred to our hospital. Magnetic resonance imaging showed fluid in the tibial bone tunnel and extensive bone marrow edema surrounding the bone tunnel. Based on these findings, abscess formation within the tibial bone tunnel and osteomyelitis spreading to the proximal tibia were suspected. During the surgery, a portion of artificial ligament and non-absorbable suture were observed in the bone tunnel, and the infection healed immediately after removal of this complex. When surgical site infection occurs after ACL reconstruction, it is important to completely remove all artificial materials as early as possible.