Recent studies have established a relationship between surgeon volume and patient outcomes in the field of spine surgery. Given the additional complexity of spinal deformity surgery, especially when spinopelvic fixation is included, younger surgeons without years of experience may be particularly disadvantaged.
Caleb M. Yeung, MD, a former resident in the Department of Orthopaedic Surgery at Brigham and Women’s Hospital, Melvin C. Makhni, MD, MBA, director of Complex Spinal Reconstruction in that department, and colleagues conducted the first study on this question, which they published in Clinical Spine Surgery. They determined spinal deformity cases were indeed associated with high complication rates, although low mortality.
The researchers reviewed 461 cases of posterior spinal instrumented fusion for an adult deformity that spine surgeons submitted to the American Board of Orthopaedic Surgery (ABOS) for the Part II Oral Examination between 2008 and 2017. The average duration of follow-up was 9.4 weeks. 60 cases (13%) included pelvic fixation.
The surgeon-reported data had been independently certified by the hospitals where they performed the procedures.
Overall Complication Rates
Among all patients with spinal deformity, the complication rates were:
- Surgical complication—22%
- Medical complication—17%
- Any complication—32%
Results by Pelvic Fixation or Not
The use of spinopelvic fixation was associated with poorer outcomes in some respects:
- Surgical complication—42% of patients with pelvic fixation vs. 20% of those without (P<0.001)
- Need for reoperation—14% vs. 5% (P=0.036)
- Readmission—17% vs. 7% (P=0.049)
There was no significant difference between patients who underwent pelvic fixation and those who did not with regard to mortality (0 vs. 2 deaths, respectively) or anesthesia complications (1.7% vs. 1.2%).
In adjusted multivariable testing, there was no significantly increased risk of overall complications or surgical complications among patients who underwent pelvic fixation compared with those who did not.
Pelvic Fixation and Specific Complications
With regard to surgical complications, pelvic fixation was associated with higher rates of:
- Fracture—5.0% of patients with pelvic fixation vs. 1.2% of patients without (P=0.038)
- Infection—13% vs. 2% (P<0.001)
Significantly more common medical complications were:
- Respiratory failure—3.3% vs. 1.7% (P<0.001)
- Dermatologic complaints—1.7% vs. 0% (P=0.010)
- Postoperative confusion/delirium—8.3% vs. 2.5% (P=0.017)
- Arrhythmia—3.3% vs. 0.5% (P=0.027)
- Postoperative anemia—10.0% vs. 3.5% (P=0.021)
Interpreting the Findings
Patients who received pelvic fixation were significantly older than those who did not (age 60 vs. 35; P<0.001). That probably accounts for some of the discrepancies in surgical and medical complications (candidates for Board certification were not asked to report comorbid conditions to the ABOS).
Still, these data suggest spine surgeons in early independent practice are likely to encounter difficulties when undertaking adult spinal deformity cases. It’s hoped the findings will inform shared decision-making with patients and prompt newer surgeons to discuss these cases with more senior colleagues.