Sigmoid perforation after medial migration of lag screw in gamma nailing.

Medial lag screw migration in Gamma nailing is a rare complication. In an 84-year-old woman, the medial migration of the lag screw into the pelvic was observed 8 weeks after intramedullary osteosynthesis of a trochanteric fracture by Gamma nailing. Total hip replacement was performed after removal of the Gamma nail. Twelve weeks later, the patient developed a sepsis and was revised for retroperitoneal abscess formation extended to the interested hip region. The reason for the retroperitoneal abscess was the undetected sigmoid perforation due to the migrated lag screw. After radical surgical and antibiotic therapy, the complication could be handled with a satisfactory clinical outcome.