A novel technique for sublaminar-band-assisted closure of pedicle subtraction osteotomy

Abstract

Sagittal imbalance is a spinal deformity with multifactorial etiology, associated with higher risk of low back pain, disability and poor health-related quality of life [1, 2]. Pedicle subtraction osteotomy (PSO) is the most commonly performed osteotomy to increase lumbar lordosis and gain a balanced spine on the sagittal plane in adults with sagittal imbalance [3, 4]. PSO is a technically demanding procedure and poses significant risk on the patient, especially in the elderly [5], including mortality from bleeding and perioperative complications. Insufficient correction has demonstrated to be a risk factor for poor results and reoperation [6–9]. Some key aspects for the successful execution of a PSO for sagittal imbalance are preoperative planning with calculation of the amount and site of needed correction, a team approach with advanced hemodynamic and neurophysiological intraoperative monitoring, adequate pelvic fixation, effective closure of the osteotomy, intraoperative measurement of the amount of correction obtained and adequate selection of the upper limit of instrumentation [10–15]. Though usually a combination of forces directly applied to the spine, bending of the table and application of forces through pedicle screws allows for straightforward closure of the osteotomy, in some cases a good reduction is difficult to obtain due to sclerosis of the vertebral body where the osteotomy is performed or bone fragility, with risk of implant failure when high modulus forces are applied through pedicle screws. In this paper, we present a novel technique based on application of forces through the osteotomy with sublaminar bands in help closure of the osteotomy and increase the stiffness of the final construct around the PSO.