Radiographic and perioperative outcomes following anterior thoracic vertebral body tethering and posterior lumbar spine tethering: a pilot series.

BACKGROUND AND CONTEXT:  In patients with adolescent idiopathic scoliosis (AIS) of main thoracic and lumbar spine regions, combined anterior thoracic vertebral body tethering and posterior lumbar spine tethering (ATVBT/PLST) is a novel non-fusion treatment option for growth modulation and conservation of motion. METHODS:  Fourteen patients with AIS who underwent ATVBT/PLST with at least 2-year follow-up were included. Primary outcomes included quality of life as assessed by SRS-22 instruments, radiographic analysis, and revision operations. We secondarily reported perioperative metrics and post-operative opiate morphine equivalents (OME). Clinical success was defined as patients who achieved skeletal maturity with ≤ 30° curve magnitude of both their main thoracic and thoracolumbar/lumbar curves and who did not undergo posterior spine instrumentation and fusion (PSIF). RESULTS: Patients had a mean age of 11.6 years (range 10-14 years), majority were girls (92%), and mean follow-up was 3.0 years (range 2-4.8 years). All patients were skeletally immature with a Risser ≤ 2. Included curves were Lenke 1C, 3C, or 6C. Mean preoperative curve magnitudes were 53° ± 8° (range 45°-65°) main thoracic and 49° ± 9° (range 40°-62°) thoracolumbar/lumbar curves. At most recent follow-up, patients had a mean main thoracic curve of 29° ± 8° (range 15°-40°) and a mean thoracolumbar/lumbar curve of 20° ± 15° (range 4°-35°). 50% required a revision operation. Cable breakage occurred in 43%, which did not always require revision. One patient progressed to thoracic fusion, but no patient underwent lumbar fusion. Patients had a mean SRS-22 outcome score of 4.2 ± 0.4. CONCLUSIONS: ATVBT/PLST is a potential alternative to spine fusion for select immature patients with AIS at a minimum 2-year follow-up. ATVBT/PLST potentially offers motion conservation at the cost of a higher revision rate. Further study and reporting of results are necessary to refine indications and techniques, which in turn will improve outcomes of this procedure. LEVEL OF EVIDENCE: Level IV-Case series without comparative group.