Operative treatment for adult spinal deformity (ASD) provides significant improvement in health-related quality of life at minimum three-year follow-up (mean 4.1 years), suggesting that the benefits of surgery for ASD remain durable long term. This is the key message to come out of a recent study which was published in the Journal of Neurosurgery: Spine by Elias Elias (University of Virginia, Charlottesville, USA) et al.
The researchers note that the findings of this prospective multicentre analysis “should prove useful for counselling, cost-effectiveness assessments, and efforts to improve the safety of care”.
They state that longer term durability is important given the invasiveness, complications, and costs of these procedures and so the aim of the study was to assess minimum three-year outcomes and complications of ASD surgery.
Operatively treated ASD patients were assessed at baseline, follow-up, and through mailings. Patient-reported outcome measures (PROMs) included scores on the Oswestry Disability Index (ODI), Scoliosis Research Society–22r (SRS-22r) questionnaire, mental component summary (MCS) and physical component summary (PCS) of the SF-36, and numeric rating scale (NRS) for back and leg pain.
Complications were classified as perioperative (≤ 90 days), delayed (90 days to two years), and long term (≥ two years). Analyses focused on patients with minimum three-year follow-up.
Out of a total of 569 patients, 427 (75%) with minimum three-year follow-up (mean ± standard deviation [range] 4.1 ± 1.1 [3–9.6] years) had a mean age of 60.8 years and 75% were women. Operative treatment included a posterior approach for 426 patients (99%), with a mean ± standard deviation (SD) 12 ± 4 fusion levels. Anterior lumbar interbody fusion was performed in 35 (8%) patients, and 89 (21%) underwent three-column osteotomy.
The study found that all PROMs improved significantly (p<0.001) from baseline to last follow-up, including scores on ODI (45.4 to 30.5), PCS (31 to 38.5), MCS (45.3 to 50.6), SRS-22r total (2.7 to 3.6), SRS-22r activity (2.8 to 3.5), SRS-22r pain (2.3 to 3.4), SRS-22r appearance (2.4 to 3.5), SRS-22r mental (3.4 to 3.7), SRS-22r satisfaction (2.7 to 4.1), NRS for back pain (7.1 to 3.8), and NRS for leg pain (4.8 to 3).
Degradations in some outcome measures were observed between the two-year and last follow-up evaluations, but the magnitudes of these degradations were modest and arguably not clinically significant, note the researchers.
Overall, 277 (65%) patients had at least one complication, including 185 (43%) perioperative, 118 (27%) delayed, and 56 (13%) long term. Notably, the 142 patients who did not achieve three-year follow-up were similar to the study patients in terms of demographic characteristics, deformities, and baseline PROMs and had similar rates and types of complications.
Speaking to Spinal News International, Elias said: “Adult spinal deformity patients present with significant pain and disability, that affect their quality of life and end up with marked functional impairment and neurological deficits.
“We already know that deformity surgeries have short-term benefits at least for the first one or two years, but what about the long-term durability of the outcome? As spine surgeons, we should take into consideration the high cost, the invasiveness, and the early and delayed complications of this procedure and justify to the patient the reason we are offering the surgical option.
“Our paper is one of the largest prospective studies conducted among 11 different sites in the United States to assess the outcomes and the rates and types of complications associated with adult spinal deformity surgery. We were able to demonstrate that the durability of the good outcome was maintained at a mean of four-year follow-up despite the associated complication rates.
“We should remember that after all, adult spinal deformity surgery is a journey for both the patient and the surgeon. The ride is bumpy but the outcome is satisfactory.”