Level of injury and surgical approach affect DVT risk after spinal trauma repair

Lumbar spine injuries requiring an anterior surgical approach may substantially increase the risk for thromboembolic complications.

Factors associated with an increased risk of deep venous thromboembolism after total hip and knee arthroplasty also increase the risk of the disease after surgery for spinal trauma, a retrospective study found. However, the surgical setting and level of the injury also affect patients' risks, the study authors said.

Patrick Platzer, MD, and colleagues at the University of Vienna Medical School, Austria, reviewed the records for all patients treated for significant skeletal and non-skeletal spinal injuries at Vienna General Hospital between 1980 and 2004. Data for all patients were contained in the hospital's trauma registry.

After applying exclusion criteria, 978 patients treated at an average age of 40 years were included in the study. Of these, 727 patients underwent surgery for spinal fractures, 205 for spinal fractures with dislocation and 46 due to discoligamentous instabilities. Also, 466 patients had isolated injuries and 512 had concomitant injuries, according to the study.

Overall, 522 patients (53%) showed preoperative lower extremity neurological deficits, including motor or sensory defects, or both. Of these, 441 patients (84%) showed complete recovery postoperatively and 81 patients (16%) showed incomplete recovery.

Postoperatively, 792 patients (81%) received antithrombotic prophylaxis consisting of low-molecular-weight heparin and 153 patients (16%) also received graduated compression stockings. Another 21 patients received compression stockings only, and 12 patients received no prophylaxis.

The researchers found that 22 patients (2.2%) developed symptomatic thromboembolic complications after surgery despite receiving antithrombotic prophylaxis. This included four women and 18 men followed for an average 17 days postop. Of these 22 patients, 17 had clinical signs of deep venous thromboembolism (DVT) and four of these patients subsequently developed pulmonary embolism (PE). In addition, five patients experienced PE without prior signs of DVT, according to the study.

Six patients died after experiencing PE, the authors noted.

Regarding general risk factors for such complications, "19 of 22 patients declared regular smoking, seven patients suffered from adipositas, and two patients had a relevant bleeding disorder," the authors wrote.

"Regression analysis also showed that thromboembolic complications were seen more frequently in patients with surgical procedures at the lumbar spine and in patients who underwent [an] anterior spinal approach," they reported. Patients with lower extremity motor defects also had a higher incidence of DVT, they added.

"The combination of these factors in particular, injury of the lumbar spine requiring anterior surgical approach, may substantially increase the risk of developing thromboembolic complications postoperatively," they noted.

For more information:
Platzer P, Thalhammer G, Jaindl M, et al. thromboembolic complications after spinal surgery in trauma patients. Acta Orthop. 2006;77:755-760.