429 - The National Burden of Revision Spinal Fusion: A Focus on Patient Char...

#429 The National Burden of Revision Spinal Fusion: A Focus on Patient Characteristics and Complications

Oral Posters: Quality of Spine Care

Presented by: H. Bae

Author(s):

S. Rajaee (1)
H.W. Bae (2)
L.E. Kanim (3)

(1) Tufts University School of Medicine, Boston, MA, USA
(2) Cedars-Sinai Spine Center, Department of Surgery, Div of Orthopaedics, Los Angeles, CA, USA
(3) Spine Research Foundation/Cedars-Sinai Spine Center, Los Angeles, CA, USA

Abstract

Background: Frequency of spinal fusions performed annually in the U.S. is increasing rapidly. This study presents national trends in revision spinal fusion along with a comprehensive comparison of co-morbidities, inpatient complications and surgical factors in revision spinal fusion to primary fusion. We hypothesized that revision fusions have increased at a lower rate than primary fusions, and that refusion discharges are associated with a higher rate of comorbidities and complications.

Methods: Using the nationwide inpatient sample, we performed a retrospective cohort analysis and compared trends in revision versus primary spinalfusion from 2002 to 2009 and compared the comorbidity burden of primary versus revision spinal fusion. Using multiple variable logistic regression techniques, factors that were independently associated with revision fusion relative to primary fusion were presented.

Results: In 2009, there were 410,158 primary spinal fusion discharges and 22,128 refusion discharges. Refusions represented 5.1% of the total number of annual fusions performed (vs. 5.3% in 2002). From 2002 to 2009, primary fusions increased at a higher rate than refusions (56.4% vs 51.0%) (p< 0.05). Length of stay and hospital charges were higher for refusion discharges (4.2 days vs. 3.8 days , p< 0.0001; $91,909 vs. $87,161, p< 0.0001). In 2009, BMP was used more in refusion cases than primary cases (39.7% vs 27.6%), while interbody devices were used less in refusion cases (41.7% vs 56.4%) (p< 0.05). In the multiple variable logistic regression model for all spinal fusions, depression (odds ratio, 1.53; p < 0.0001), psychotic disorders (odds ratio, 1.49; p < 0.0001), deficiency anemias (odds ratio, 1.35; p < 0.0001) and smoking (odds ratio, 1.10; p < 0.01), occurred more frequently in revision spinalfusion discharges, adjusting for other variables. The most common primary diagnosis was ICD9 996.49 (mechanical complication of internal orthopedic device, implant and graft) for cervical, thoracic and lumbar refusion.

Conclusion: The national refusion rate has increased at a lower rate than primary fusions from 2002 to 2009. Length of stay and hospital charges were higher for refusions, while inpatient mortality was less.