68. Incidence of Surgical Site Infection Following Adult Spinal Surgery and Analysis and Prevalence of Risk Factors

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Proceedings of the NASS 24th Annual Meeting / The Spine Journal 9 (2009) 1S-205S

67. Scoliosis Research Society Morbidity and Mortality of Adult Scoliosis Charles Sansur, MD1, Jeffrey Coe, MD2, Justin Smith, MD, PhD3, Christopher Shaffrey, MD4, Sigurd Berven, MD5, Paul Broadstone, MD6, Theodore Choma, MD7, Michael Goytan, MD, FRCSC8, Hilali Noordeen, MD9, Raymond Knapp10, Robert Hart, MD11, Reinhard Zeller, MD, FRCSC12, William Donaldson, MD13, David Polly, Jr., MD14, Joseph Perra, MD15, Oheneba Boachie-Adjei, MD16; 1University of Virginia, Charlottesvile, VA, USA; 2Campbell, CA, USA; 3University of Virginia, Charlottesville, VA, USA; 4Charlottesville, VA, USA; 5University of California, San Francisco, San Francisco, CA, USA; 6Erangler Medical Center, Chattanooga, TN, USA; 7University of Missouri-Columbia, Columbia, MO, USA; 8University of Manitoba, Winnipeg, Manitoba, Canada; 9Stanmore, Middlesex, United Kingdom; 10Orlando, FL, USA; 11Portland, OR, USA; 12Hospital for Sick Children, Totonto, Ontario, Canada; 13University of Pittsburgh, Pittsburgh, PA, USA; 14University of Minnesota, Minneapolis, MN, USA; 15 Twin Cities Spine Center, Minneapolis, MN, USA; 16Hospital for Special Surgery, New York, NY, USA BACKGROUND CONTEXT: The Scoliosis Research Society (SRS) has maintained a morbidity and mortality index to track their complication rates. Due to the large number of cases reported in the SRS database, this review has the potential to be the most comprehensive reported assessment of the operative and perioperative morbidity and mortality (M&M) for patients undergoing surgery to treat degenerative and idiopathic adult scoliosis (AS). PURPOSE: The SRS M&M database was reviewed to obtain an assessment of complication incidence in adult scoliosis patients, and to determine if complication rate was influenced by various clinical parameters. STUDY DESIGN/SETTING: Retrospective review of large case series. PATIENT SAMPLE: Patient sample was composed of 2555 individauls with degenerative scoliosis, and 2425 with idiopathic scoliosis. OUTCOME MEASURES: Overall complication rate. Influence of complication according to: age, type of scoliosis, history of revision surgery, use of osteotomy, and surgical approach. METHODS: The SRS M&M database was queried to identify cases of AS from 2004-2007. Complications were identified and analyzed based on patient age, type of scoliosis, use of osteotomy, revision surgery status, and surgical approach. Age was stratified into less than or equal to 60 and greater than 60. Surgical approach was stratified into: anterior only, posterior only, anterior and posterior, and unspecified. RESULTS: 4980 cases of AS were submitted from 2004-2007. There were a total of 521 complications (10.5%). The most common complications were dural tear 142 (2.9%), superficial wound infection 46 (0.9%), deep wound infection 73 (1.5%), implant complication 80 (1.6%), acute neurologic deficits 49 (1.0%), delayed neurologic deficits 41 (0.5%), epidural hematoma 12 (0.2%), wound hematoma 22 (0.4%), pulmonary Embolus 12 (0.2%), pulmonary complication 31 (0.5%), deep venous thrombosis 9 (0.2%). There were 17 deaths making the mortality rate (0.3%). Age and scoliosis type did not result influence the complication rate (P50.32, 0.20). Patients who underwent osteotomies, who were having Clinical Category

No. Cases

No. Complications, (%)

P Value

Degenerative Scoliosis Idiopathic

2555 2425

281 (11.0%) 240 (9.9%)

0.20

No Osteotomy Osteotomy

3887 1093

376 (9.7%) 145 (13.3%)

0.0006

No Revision Revision

3973 1007

392 (9.9%) 129 (12.8%)

0.006

Anterior Only Posterior Only Anterior and Posterior Unspecified

611 3154 804 409

53 (8.7%) 325 (10.3%) 102 (12.7%) 40 (9.85%)

0.03*

* Complication rate was significantly higher in anterior and posterior group when compared to the combination of anterior only and posterior only groups. Table.

revision surgery, and who were undergoing anterior and posterior surgery had significantly higher rates of complication (P50.0006, 0.006, 0.03). CONCLUSIONS: The rate of complications for treatment of AS is 10.5%. Complication rate is significantly higher in patients undergoing osteotomies, revision procedures, and combined anterior/posterior approaches. Complication rate is not influenced by age or scoliosis type. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. doi: 10.1016/j.spinee.2009.08.081

68. Incidence of Surgical Site Infection Following Adult Spinal Surgery and Analysis and Prevalence of Risk Factors Albert Pull Ter Gunne, MD, David Cohen, MD, MPH; Johns Hopkins University, Baltimore, MD, USA BACKGROUND CONTEXT: A surgical site infection (SSI) is a common complication after spinal surgery. It occurs between 0.7 and 12% of patients and leads to higher morbidity, mortality and healthcare costs. Small patient group and case-control research has been performed to identify risk factors for SSI. The design of these studies make it impossible to perform sub-group and post-hoc analysis and determine absolute patient risks. We performed a high volume cohort study to identify risk factors for postoperative wound infection, that may result in strategies to reduce the risk for SSI. PURPOSE: To asses the incidence and indentify risk factors for SSI in adult spine surgery population. STUDY DESIGN/SETTING: Retrospective study, within the spine division of the orthopaedic department of our institution, between June 1996 and December 2005. PATIENT SAMPLE: All 3174 adult patients who underwent orthopaedic spinal surgery at our institution between June 1996 and December 2005. Patients who developed a postoperative wound infection were compared to the rest of the cohort. OUTCOME MEASURES: SSI after orthopaedic spinal surgery. Infections were also stratified into deep or superficial SSI for further analysis. METHODS: Retrospectively, we abstracted all 3174 electronic patient record. Individual patient and perioperative characteristics were stored in an electronic database. RESULTS: In total, 132 (4.2%) patients were found to have a SSI with 84 having deep based infection. Estimated blood loss over 1 liter (p50.017), history of prior SSI (p50.012) and diabetes (p50.050) were found to be independent statistically significant risk factors for SSI. Obesity (p50.009) was found to significantly increase the risk of superficial infection, while anterior spinal approach decreased that risk (p50.010). Diabetes (p50.033), obesity (p50.047), previous SSI (p50.009) and longer surgeries (2-5 hours (p50.023) and 5 or more hours (p50.009)) were found to be independent significant risk factors for deep SSI. CONCLUSIONS: SSI is commonly seen after spinal surgery. A prior SSI, diabetes and obesity all increased the risk of SSI. Higher EBL and longer operative times also increase risk of different types of SSI while anterior approaches to the spine were associated with the lowest risk of SSI. In obese diabetic patients, pre-operative weight reduction could be considered to decrease a patient’s risk of SSI: as well a surgeon should chose operative strategies that attempt to minimize blood losses and operative times while utilizing an anterior surgical approach when feasible. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. doi: 10.1016/j.spinee.2009.08.082

69. ‘‘Morphologic Change of Modic Change’’: A Sign on the Postoperative Spondylodiscitis in Patients with Modic Change of Degenerative Spine Wei Chiang Liu, MD1, Kyeong Hwan Kim, MD, PhD1, Gun Choi1, Sang-Ho Lee, MD, PhD, FRCS1, Jin Wook Choi2, Hyeon Seon Park, MD3,