Migration of anterior spinal rod from the dorsolumbar spine to the knee: an unusual complication of spinal instrumentation.

Abstract

A retrospective case report. The objective of the present article is to report an unusual complication of spinal instrumentation. Migration of spinal implants to distant site is quite unusual, and literature till date has only 2 case reports. For the first time, we are reporting a case of anterior spinal rod migration from the dorsolumbar spine to the knee joint in a young male patient after 4 years of its fixation following spinal injury. A 38-year-old man presented with pain, swelling, and restriction of movement of left knee joint. On clinical examination, a hard movable rod was palpable which was suspected to be a metallic foreign body initially. The detailed history of the patient revealed anterior spinal fixation following posttraumatic injury of L1 vertebra 4 years back. Radiograph showed a metallic rod lying around the knee joint with absence of anterior rod of dorsolumbar spine. The suspicion of migration of the rod was confirmed by surgical exploration. After 1 week of removal of the rod, patient became totally asymptomatic with normal full range of movement of the knee joint. Though rare, migration of implants from the spine to the distant sites is always a possibility and may have severe complications too. We stress the need of long-term follow-up with clinical examination and radiographs to prevent missing such a complication.