Utility of early postoperative radiographs after posterior spinal fusion for adolescent idiopathic scoliosis.

STUDY

DESIGN

Retrospective.

OBJECTIVE

Evaluate the ability of serial full-length spine radiographs to detect clinically significant implant-related (IR) and non-implant-related (NIR) radiographical abnormalities in the first 6 months after routine posterior spinal fusion for adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA: Patients with AIS are exposed to repeated doses of ionizing radiation during the course of their treatment with potential consequences for their long-term health. Postoperative algorithms for AIS often involve frequent standing plain radiographs during the first 6 months after surgery to detect IR and NIR abnormalities that may impact a patient's clinical course. However, the actual clinical utility of such repeated spine radiographs has not been studied.

METHODS

Retrospective chart and radiographical review was conducted at a single institution for patients with AIS after posterior spinal fusion between 2007 and 2012. Radiographical abnormalities identified on full-length spine radiographs or additional imaging modalities in the first 6 postoperative months were grouped into IR or NIR findings. The findings were considered clinically significant if they resulted in a deviation from an anticipated postoperative course or additional interventions.

RESULTS

For 129 patients, 761 full-length spine radiographs were obtained in the first 6 postoperative months. Eight patients (11 radiographs) had IR or NIR abnormalities, with only 2 of these considered clinically significant. Seven of the remaining 121 were identified to have IR or NIR abnormalities using other imaging modalities, with 2 considered clinically significant. The sensitivity and specificity of a full-length spine radiograph for detecting a clinically significant abnormality was 50% and 95%, respectively.

CONCLUSION

Routine full-length spine radiographs used with high frequency in the first 6 months after posterior spinal fusion rarely detected a radiographical abnormality that resulted in a meaningful change to a patient's clinical management. Blanket postoperative screening algorithms should be reconsidered to minimize patient radiation exposure.