Clinical considerations for spinal surgery in the osteoporotic patient: A comprehensive review

Abstract

Osteoporosis is a skeletal condition characterized by low bone mineral density (BMD). Common in older patients undergoing spinal fusion, it is a significant risk factor for instrumentation failure and related complications. The objective of this review is to articulate clear suggestions for screening and medical/surgical management strategies in patients with osteoporosis. A thorough review of the literature was conducted using PubMed. Varied search terms were applied to yield published manuscripts on osteoporosis and spine surgery. Biomechanical studies and studies conducted in animal models were excluded. Screening should be considered in those that present with multiple risk factors for low BMD. Dual-energy x-ray absorptiometry (DEXA) remains the gold standard, but Hounsfield Units (HU) have emerged as a powerful complement to DEXA. While both bisphosphonates and teriparatide have been investigated in the perioperative setting and have a positive impact on outcomes, teriparatide maintains an advantage in comparative studies. Surgical treatment need not be postponed. Standard surgical modifications such as using multiple points of fixation, varied fixation equipment, anterior/posterior instrumentation, and modified screw design/trajectories should all be considered. However, recent clinical studies focus on cement augmentation and expandable pedicle screws. All have been shown to improve bone-screw interface strength, but extravasation remains a risk of cement augmentation, and hydroxyapatite cement (HAC), while an emerging alternative to polymethyl methacrylate (PMMA), is not as well investigated in the setting of osteoporosis. Furthermore, research on expandable pedicle screws is limited. To conclude, optimizing spine surgery outcomes in the osteoporotic patient is possible with a thorough preoperative workup, medical management, and a tailoring of the surgical technique. This is especially important when performing complex spinal instrumentation.

Keywords: DEXA; Osteopenia; Osteoporosis; Spinal instrumentation; Spine surgery.