Major complications in primary adult deformity surgery: Risk factors and clinical outcomes at one institution with 2-6 follow-up
The goals of our study were 1) identify risk factors for the development of major complications, and 2) determine if major complications precluded a successful ultimate clinical outcome. We analyzed 124 consecutive primary adult deformity patients from one institution and identified age >60 yrs, =3 comorbidities, fusion to sacrum, history of cancer, and osteoporosis as significant predictors of a major complication. Irrespective of developing a major complication, patients experienced significant clinical improvement from baseline in ODI and SRS scores at 2-6yrs.
We hypothesize the following: 1) there exist certain identifiable patient and surgery-related risk factors for developing a major complication, and 2) patients who sustain a major complication are at greater risk for less clinical improvement at 2-6 yrs post-operatively compared with minor-only and no complications groups.
Assessment of 124 consecutive, primary adult deformity patients with a minimum age of 40 yrs treated at a single institution from 2002-2006. All complications were identified and classified as either major or minor (Glassman, Spine, 2007). Risk factors for complications and their effect on ODI and SRS clinical outcomes were assessed.
120 females (age: 56 yrs, range 40-81) and 4 males met inclusion criteria. Diagnosis was adult scoliosis in 85% (105/124), degenerative scoliosis in 11% (14/124), hi-grade spondylolisthesis in 3% (4/124), and 1 kyphosis. There was 1 surgery-related death, no blindness or major neurologic deficits. The prevalence of complications was: 15% major (19/124) and 15% minor-only (19/124). Risk factors for major complications included age >60 yrs (p=0.002), =3comorbidities (p=0.006), osteoporosis (p=0.01), history of cancer (p=0.03), and fusion to sacrum (p=0.01). All groups (major, minor, and no complications) experienced statistically equivalent and significant improvement in SRS and ODI clinical outcomes from baseline (Table 1). Patients with major complications had similar SRS and ODI scores at baseline and at 2-6yrs follow-up were not statistically different than the minor-only and no complications groups (p>0.05).
Major complications can be expected in 15% of patients undergoing spinal fusion for primary adult deformity surgery. Older patients with osteoporosis, a history of cancer, =3 comorbidities, or fused to sacrum are predisposed to developing a major complication. The occurrence of a major complication does not have a negative impact on ultimate clinical outcome.
Surgeons should inform older patients with osteoporosis, a history of cancer, =3 comorbidities, or who will be fused to sacrum that their risk for major complications is higher, but that they ultimately do no worse than those who avoid major complications, provided there is no blindness or permanent neurologic deficit.
Table 1. Within group comparisons (preop vs final)*