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.