Radiological Outcomes in Adolescent Idiopathic Scoliosis Patients More Than 22 Years After Treatment

STUDY DESIGN: Longitudinal cohort.

OBJECTIVES: To evaluate the long-term radiologic outcomes in adolescent idiopathic scoliosis (AIS) patients more than 22 years after treatment.

SUMMARY OF BACKGROUND DATA: Although treatment for AIS is prophylactic and is aimed at preventing curve progression, very few studies report long-term outcomes of treatment.

METHODS: AIS patients treated with Boston brace or posterior spinal fusion (PSF) with Harrington-dorso-transverse traction (DTT) instrumentation from 1983 to 1990 were requested to return to clinic. Subsequently, 36-inch standing radiographs were obtained after patient consent. Cobb angles were compared with pretreatment and immediate posttreatment radiographs. Any evidence of adjacent-level disease or local kyphosis was also noted.

RESULTS: One hundred fifty-nine (78%) of 219 patients were available for follow-up, 66 braced and 93 surgical. There were 85 females with an average age at surgery of 14.3 years and an average age at follow-up of 37.6 years. The mean length of follow-up was 24.5 years (range, 22-30 years). There was a statistically significant curve progression of 2.9° in the PSF group. There was a greater degree of curve progression in the braced group (5.5°), but this was not statistically significant. Proximal segment degeneration was seen in 8 (5%), 2 in the brace cohort and 6 in the PSF cohort. Distal segment degeneration was seen in 26 (16%) patients, 4 treated with brace and 22 treated with PSF. No patient developed proximal junction kyphosis. Three patients in the PSF cohort required additional surgery for distal adding-on. Four patients had a noncontiguous L5-S1 fusion, three from the PSF cohort and one from the braced cohort.

CONCLUSION: In this cohort with an average follow-up of 24.5 years, with 78% available for follow-up, both the braced and surgically treated patients had a very small degree of curve progression, with a small incidence of distal segment degeneration and reoperation.

LEVEL OF EVIDENCE: III.