Unusual presentation of spinal cord compression related to misplaced pedicle screws in thoracic scoliosis

Utilization of thoracic pedicle screws is controversial, especially in the treatment of scoliosis. We present a case of a 15-year-old girl seen 6 mont hs after her initial surgery for scoliosis done elsewhere. She complained o f persistent epigastric pain, tremor of the right foot at rest, and abnorma l feelings in her lens. Clinical examination revealed mild weakness in the right lower extremity, a loss of thermoalgic discrimination, and a forward imbalance. A CT scan revealed at T8 and T10 that the right pedicle screws w ere misplaced by 4 mm in the spinal canal. At the time of the revision surg ery the somatosensory evoked potentials (SSEP) returned to normal after scr ew removal. The clinical symptoms resolved 1 month after the revision. The authors conclude that after pedicle instrumentation at the thoracic level a spinal cord compression should be looked for in case of subtle neurologic findings such as persistent abdominal pain, mild lower extremity weakness, tremor at rest, thermoalgic discrimination loss, or unexplained imbalance.