Cement-Augmented Versus Conventional Pedicle Screws in Surgical Management of Osteoporotic Vertebral Fractures.

objectiveCement-augmented pedicle screws (CAPS) are expected to have fewer complications than conventional pedicle screws (PS), including less risk of postoperative screw loosening and loss of correction. However, use of CAPS has been associated with a risk of other complications, such as cement leakage. In this study, we investigated the usefulness of CAPS for osteoporotic vertebral fractures (OVF) by comparing its surgical outcomes with those of PS.

methodsThe study included 46 patients (PS group, n=29; CAPS group, n=17) who underwent posterior fixation surgery for OVF at our hospital or an affiliated hospital between August 2019 and August 2023 and were followed up for 12 months postoperatively. We collected background information on each patient, including age, sex, body mass index, diagnosis, and whether they were receiving osteoporosis treatment. We also examined the level of the lesion, the range of fixation (1-1, 2-2, 3-3), whether posterior bone grafting was performed, whether anterior column reconstruction was performed, and the corrected angle. We compared surgery-related factors, including the rate of revision surgery within 12 months postoperatively, adjacent vertebral fracture, screw loosening, and loss of angle correction at 12 months postoperatively between the two groups. We also evaluated cement leakage in the CAPS group. Logistic and linear regression analyses were used to evaluate the factors associated with each outcome.

resultsThe Elixhauser Comorbidity Index value was significantly higher in the PS group, (P=0.042), but there were no significant differences between the groups in other factors. Cement leakage was confirmed in seven of the 17 cases in the CAPS group, all of which were asymptomatic. There was no significant difference between the groups in the incidence of adjacent vertebral fractures, screw loosening, or loss of correction. There was also no significant difference in the incidence of early revision surgery between the PS group (7/36 cases) and the CAPS group (7/40 cases). The risk of adjacent vertebral fracture was shown to be significantly higher at the thoracic level than at the thoracolumbar level (odds ratio 34, P=0.043). The risk of thoracic vertebral fracture was significantly higher than that of thoracolumbar vertebral fracture in cases with loss of angle correction (B=1.312, P=0.029). No significant risk factors for screw loosening were identified.

conclusionsThere was no significant difference in surgical outcomes between CAPS and conventional PS when used in posterior fusion surgery for thoracolumbar fractures. However, use of CAPS was associated with a risk of cement leakage. Therefore, the indications for its use should be carefully considered. Long-term, large-scale prospective studies are needed to assess the usefulness of CAPS in more detail.