Major complications seen in 7.6% of adult spinal deformity surgeries


Excessive blood loss, deep wound infection and pulmonary embolism are the most common complications following adult spinal deformity surgery, a new study has shown. In this multicentre, retrospective, consecutive review of patients undergoing spinal deformity surgery, major complications occurred in 7.6% of the patients.

The results of the study were presented by Frank J Schwab, chief of the Spinal Deformity Service at NYU-Hospital for Joint Diseases, New York, USA, at the SAS11 conference.


“Complications following adult spinal deformity surgery have a reported incidence of 27–80%,” he said. “Understanding risk factors for complications may reduce their occurrence and permit improved operative risk-benefit ratios. The purpose of the study was to identify patient and surgical parameters that correlate with development of major peri-operative complications following adult spinal deformity surgery.”


The analysis included 953 adult spinal deformity patients at eight centres with a minimum follow-up of two years. The investigators identified patients with major peri-operative complications, and a randomisation table was used to select a control group of patients that did not suffer major complications). Data collected included demographics, past medical history, ASA grade, comorbidities, pre-operative lab values, intra/post-operative parameters, and occurrence of peri-operative complication.


The results, Schwab said, showed 99 major complications in 72 patients (7.6%), an average 1.4 per patient. The matched control group cohort consisted of 78 patients. No differences were noted between groups for the following: demographics, pre-op vitals, lab-results, ASA grade, respiratory signs, alcohol or smoking habits, mean operative time, and intensive care unit stay.


Chi-square analysis demonstrated that the complication group exhibited a higher percentage of staging procedures (46% vs. 37%, p=0.011), a higher percentage of anterior/posterior approach (56% vs. 32%, p=0.011) and a greater prevalence of postoperative anaemia (16.7% vs. 6.4%, p=0.04).


The most common complications were:


  • Excessive blood loss, >4L (n=11)
  • Return to operation room for deep wound infection (n=11)
  • Pulmonary embolus (n=10)


“Improved understanding of risk profiles and procedure-related parameters may assist in pre-operative risk-benefit surgical discussions and pre-emptive approaches to reduce major complications. Patients should be counselled that a major complication is more likely to occur in the setting of revision, staged, and anterior/posterior surgery,” Schwab concluded.