Migrating shrapnel: a rare cause of knee synovitis.

Unlabelled: Shrapnel injuries in soft tissues often do not require surgical excision. Metals that remain embedded in the surrounding tissue are not thought to cause significant damage and the patients are generally asymptomatic. This case presentation describes a patient who sustained a penetrating shrapnel injury to his thigh, where the metal fragment was not removed. However, more than 20 years later, the patient developed knee synovitis. On X-ray the shrapnel was seen in the suprapatellar pouch. An arthroscopy was preformed and the shrapnel was removed with full healing of the patient.

Conclusion: although nonsurgical treatment of shrapnel in soft tissues is the treatment of choice in many cases, late migration is possible, causing distal symptoms and may require surgical excision.