Study designRetrospective case series.ObjectiveTo assess the efficacy of preoperative halo-gravity traction (HGT) in the treatment for severe adult kyphosis and scoliosis.Summary of background dataPreoperative HGT improves severe curve magnitude and clinical condition in pediatric spinal deformity. However, the efficacy of HGT on severe adult spinal deformity has rarely been studied.Materials and methodsThis study included 18 patients with severe adult kyphosis and scoliosis (age >= 18) who underwent a preoperative HGT (mean 4 weeks), and subsequent definitive posterior-alone corrective fusion. Etiologies were neurofibromatosis (n=5), adult idiopathic (n=3), multiple vertebral fractures due to osteoporosis (n=1) and multiple myeloma (n=1), degenerative failed back syndrome (n=1), Scheuermann kyphosis (n=1), Marfan syndrome (n=1), and other genetic and connective tissue disorders (n=5). We reviewed baseline demographics, including coronal and sagittal radiographic profiles. The changes in major curve magnitude, pulmonary function tests (PFTs), and nutritional status were assessed between pre- and post-traction and immediate post-definitive corrective surgery.ResultsThere were 11 male and 7 female patients, aged 18-69 years with their major coronal and sagittal curves being 92.0 degrees 25.2 degrees and 111.6 degrees 40.1 degrees, respectively. The major coronal and sagittal curves were reduced by 18.4% and 16.8% after halo-traction, and 54.7% and 44.2% after definitive fusion, respectively. PFTs showed significant increase in %FEV1 and %FVC when comparing pre- and post-traction [43.0%+/- 17.4% vs. 49.6%+/- 18.7%, and 44.8%.+/- 16.7% vs. 54.3%+/- 20.7%, respectively, p<0.01 (n=11)]. Effective weight gain was observed after traction (46.8 +/- 14.5 vs. 49.3 +/- 13.5 kg, p<0.01).Conclusion >Halo-gravity traction (HGT) for severe coronal and sagittal plane spinal deformity in adult patients significantly reduced Cobb angles, improved PFTs, and allowed for effective weight gain in the preoperative period. The use of preoperative HGT is extremely beneficial to optimize the alignment and overall health of severe adult spinal deformity patients before their spinal reconstruction.Level of evidence Level IV.