Trends of inpatient spine augmentation: 2001-2008

Abstract

Background and purpose: Vertebroplasty and kyphoplasty are 2 minimally invasive spine augmentation procedures currently used in the management of vertebral compression fractures. Our aim was to examine the NIS data base to identify trends in spine augmentation procedures over time.

Materials and methods: Patients were identified from the NIS data base by using primary diagnosis codes (ICD-9-pathologic vertebral fracture, 733.13) and procedures codes (ICD-9-other repair of bone, 78.49; vertebroplasty, 81.65; kyphoplasty, 81.66). Means and their corresponding standard errors were compared for statistically significant differences by using the Z-test.

Results: Between 2001 and 2008, >240 000 inpatient spine augmentations were performed in the United States. From 2001 to 2008, there was a 741% increase in the number of hospital discharges for patients who underwent a spine augmentation, but the year-to-year rate of increase has been declining since 2001. From 2004 to 2008, >50 000 inpatient verterbroplasties and >152 000 inpatient kyphoplasties were identified. Compared with vertebroplasty, kyphoplasty patients were less often admitted from the emergency department (33% versus 56%, P < .001), had shorter postaugmentation hospital stays (2.3 versus 3.1 days, P < .001), had fewer comorbidities at presentation (1.4 versus 1.6, P < .01), and were less likely to be discharged to a long-term facility (28% versus 43%, P < .001).

Conclusions: Significant differences were noted in multiple comparisons between vertebroplasty and kyphoplasty, including length of hospital stay and discharges to long-term facilities. However, these findings may simply reflect differences in practice patterns rather than real differences in efficacy between the procedures.

Fig 1.

A, Graph shows trend over time for spine augmentation discharges. It demonstrates a steady increase (741%) in the number of discharges from 2001 to 2008 (P < .001). B, Graph shows trend over time for vertebroplasty and kyphoplasty discharges from 2004 to 2008. It demonstrates a 427% increase in vertebroplasty discharges and a 470% increase in kyphoplasty discharges over the 4-year period.

Fig 2.

A, Graph shows trend over time for discharges to long-term facilities for spine augmentations from 2001 to 2008. It demonstrates a steady increase in discharges to long-term facilities from 2003 to 2008 (P < .02). B, Graph shows trend over time for discharges to long-term facilities for vertebroplasty and kyphoplasty from 2004 to 2008. It demonstrates the increase in discharges to long-term facilities for kyphoplasty procedures (P < .02) and the relatively constant level of discharges to long-term facilities for vertebroplasty.