Long-term outcomes after posterior spine fusion for adolescent idiopathic scoliosis

Purpose of review To summarize recent literature regarding long-term follow-up after spinal fusion for patients with adolescent idiopathic scoliosis. In particular, this review includes a review of research which provides insight into long-term results after fusion using pedicle screw stabilization, a relatively new technique for which long-term follow-up is only recently available. Recent findings The literature increasingly uses patient-derived questionnaires to report outcomes. Minor residual scoliosis after fusion does not adversely affect outcomes and is well tolerated by patients without causing functional limitations. In contrast, patients who are leaning forward after fusion ('positive sagittal balance') do worse as measured by validated outcomes instruments. Although patients who undergo long fusion have higher rates of disc degeneration on magnetic resonance imaging compared with the general population, this degeneration is most often clinically silent. Summary The best available evidence suggests that most patients do well after posterior fusion for adolescent idiopathic scoliosis, although outcomes are adversely affected if patients develop positive sagittal balance. Continued surveillance will determine whether accelerated degeneration at unfused levels becomes symptomatic at longer-term follow-up or remains clinically silent.