Management of atraumatic chin-on-chest deformity in newly diagnosed multiple myeloma: illustrative case.

backgroundPatients with multiple myeloma (MM) are commonly managed by multidisciplinary oncology teams in concordance with the neurological, oncological, mechanical, and systematic decision framework. Surgery is indicated for mechanical instability and/or neurological deficits. In neurologically intact and mechanically stable patients, chemo- and radiotherapy alone are often the mainstay treatment. OBSERVATIONS: A 66-year-old male patient presented with a kyphotic chin-on-chest deformity due to undiagnosed spinal MM. He experienced progressive neck pain and difficulty with activities of daily living (ADLs). Imaging revealed systematic bony element destruction and burst deformities at T1-2 with cervicothoracic central canal stenosis. Due to his disease burden and neurological preservation, spinal alignment was initially achieved via halo traction and immobilization, allowing him to begin systemic therapy almost immediately after diagnosis and improving vertebral bone density and construct integrity prior to surgery. He underwent C2-T10 decompression and instrumented fusion with cement augmentation. At 12 months postoperatively, the patient reported improvement in symptomology and ADLs without radiographic evidence of hardware failure or spinal instability. LESSONS: Spinal MM with instability can be successfully managed with gradual deformity realignment and external orthosis before surgery in a neurologically intact patient with a significant disease burden. https://thejns.org/doi/10.3171/CASE2441.