An unusual complication of knee arthroscopy: an extra-articular migrated asymptomatic broken probe from the knee joint.

In large knee arthroscopy series, the complication rate has been reported to be between 2% and 8%. Although preventable in most cases, the incidence of instrument breakage remains approximately 3%. Despite this relatively frequent occurrence, few case reports have been published regarding these complications. In this case report, a patient carried a broken probe tip in her popliteal muscle belly for 5 years without symptoms. During arthroscopy, when the C-arm was temporarily not available, a probe tip had broken off and was left behind in the knee joint. It migrated through a popliteal hiatus into the popliteal fossa, and lodged in the medial head of the gastrocnemius muscle. When knee pain occurred 5 years later, the piece was located with fluoroscopy and was recovered without complications. This is the first such case reported in the English medical literature.