Outcomes of percutaneous pedicle screw stabilization for metastatic spine disease: a 10-year experience

OBJECTIVE Unstable pathological spine fractures are common in patients with cancer. Minimally invasive percutaneous instrumentation has emerged as a less traumatic alternative to conventional open spinal fixation. As cancer patient survival continues to improve, the long-term durability of this strategy and the likelihood of achieving segmental fusion remain insufficiently studied. This study aimed to describe the clinical, oncological, and surgical characteristics, including outcomes and facet fusion rates, in patients with metastatic spine disease undergoing percutaneous pedicle screw fixation at a tertiary cancer center. METHODS This retrospective cohort study evaluated patients treated using percutaneous pedicle screws and rods between 2014 and 2023. Patients without bone grafting and with postoperative imaging follow-up of more than 30 days were included. Demographic, clinical, oncological, surgical, and radiological data were collected. Postoperative CT scans were used to assess hardware breakage, screw loosening, and facet fusion, which was defined as complete bone bridging between adjacent vertebrae. RESULTS A total of 109 patients (114 constructs) were evaluated. Most patients were nonsmokers, White, and obese, with a high prevalence of prior radiotherapy and low-grade epidural tumor at the unstable level. Short constructs (1 level above and below the affected vertebra) were used in 60% of cases. Cement augmentation of pedicle screws was performed in 97% of procedures. Postoperative CT scans demonstrated some degree of cement extravasation in 85.7% of cases, but all were asymptomatic. Pain significantly improved postoperatively (visual analog scale score improvement from 6.1 to 2.5; p < 0.01). Hardware failure occurred in 6.1% of cases (n = 7), and 12.3% (n = 14) required reintervention. Segmental facet fusion occurred in 44.7% of patients, although the number of facets fused per number of facets fixed remained low at all time points: 7% at 6 months, 10% at 1 year, and 24% at 2 years. CONCLUSIONS Percutaneous pedicle screw and rod constructs provide effective and durable spinal stabilization with low complication rates and significant pain reduction. Segmental facet fusion was observed in nearly half of the patients in this study, but clinical benefits and hardware durability were independent of radiographic evidence of arthrodesis.