A randomized trial comparing 2 techniques of balloon kyphoplasty and curette use for obtaining vertebral body height restoration and angular-deformity correction in vertebral compression fractures due to osteoporosis

Abstract

Background and purpose: Vertebral compression fractures often result in pain and vertebral deformity. We compared 2 different balloon kyphoplasty techniques both using intraoperative curettage.

Materials and methods: Adults 50 years of age or older with osteoporosis and 1 acute VCF were randomized to undergo bilateral BKP in which the curette was used first (n = 57) followed by inflatable bone tamps or in which IBTs were used first, followed by curettage and a second IBT inflation (n = 55).

Results: Mean procedure duration was 33.5 and 36.8 minutes, and fluoroscopy duration was 3.8 and 3.7 minutes for the CF and IBTF groups, respectively. Two-thirds of VCFs were wedge-shaped, and one-half had dynamic mobility. Anterior height restored postoperatively was 2.28 mm (95% CI, 1.49-3.08 mm; P < .001) and 2.78 mm (95% CI, 1.89-3.66 mm; P < .001) for CF and IBTF groups, representing ∼35% and 39% of lost height restored, but group differences were not significant (P = .4). Intraoperative anterior height gain attributed to dynamic mobility was 2.96 mm (95% CI, 1.92-4.00 mm; P < .001) and 3.05 mm (95% CI, 2.10-4.00 mm; P < .001); additional height attributed to IBT inflation was 1.09 mm (95% CI, 0.77-1.41 mm; P < .001) and 1.25 mm (95% CI, 0.68-1.82 mm; P < .001), representing a 37% and 41% increase. There was no significant height loss on IBT removal and cementation. Both groups had improved pain and ambulation. Asymptomatic leakage occurred in 15% of VCFs. There was 1 nonserious device-related hematoma (IBTF group). One new clinical VCF occurred in each group, but they were not device-related.

Conclusions: Both techniques resulted in significant vertebral body height and pain improvement. Procedure and adverse event data demonstrated safe curette use in conjunction with balloon kyphoplasty procedures.

Trial registration: ClinicalTrials.gov NCT00810043.

Figures

Fig. 1.

Patient accountability.

Fig. 2.

Primary end point of absolute height restored at index vertebrae as a percentage of adjacent normal vertebrae. Group means and 95% confidence intervals are shown for measurements at the posterior, anterior, and midpoint of index vertebral bodies for each group at baseline and at 48 hours postoperatively by using standing lateral x-ray films.

Fig. 3.

Index vertebral body height gain in millimeters. CF (A) and IBTF (B) group means and 95% confidence intervals are shown for vertebral body height improvement (compared with preoperative) in millimeters, measured at the posterior, anterior, and midpoint of index vertebral bodies after prone positioning (postural reduction), IBT inflation, cementation, and postoperative steps. Preoperative and postoperative assessments used standing lateral x-rays, and intraoperative assessments used lateral fluoroscopic images.

Fig. 4.

Index vertebral body kyphosis angle. CF (A) and IBTF (B) group means and 95% confidence intervals are shown for kyphotic angulation improvement (compared with preoperative) of index vertebral bodies measured as the angle between the inferior and superior endplates of index vertebrae after prone positioning (postural reduction), IBT inflation, cementation, and postoperative steps. Preoperative and postoperative assessments used standing lateral x-rays, and intraoperative assessments used lateral fluoroscopic images.

Fig. 5.

Case illustration of kyphosis correction for each step in the kyphoplasty procedure. A, Preoperative T2 short-τ inversion recovery MR imaging. B, Preoperative standing x-ray. C, Intraoperative postural reduction without bolsters. D, Intraoperative postural reduction with a bolster. E, Intraoperative first balloon inflation. F, Intraoperative curette and second balloon inflation. G, Intraoperative cement placement. H, Postoperative standing x-ray.

Fig. 6.

Case illustration of a nonmobile fracture. A, Preoperative standing x-ray. B, Intraoperative postural reduction with a bolster. C, Intraoperative first balloon inflation. D, Intraoperative curette and second balloon inflation. E, Intraoperative cement placement. F, Postoperative standing x-ray.

Fig. 7.

Case illustration of nonmobile fracture and use of curette. A, Intraoperative postural reduction with a bolster. B, Intraoperative first balloon inflation. C, Intraoperative curette usage (used bilaterally but image shows use only on 1 side). D, Intraoperative second balloon inflation. E, Anteroposterior (AP) film of C. F, AP film of D. G, Intraoperative cement placement. H, Postoperative standing x-ray.

Fig. 8.

Postoperative back pain and ambulation. A, Group means and 95% confidence intervals are shown for the back pain numeric rating scale (0–10) measured at baseline and discharge. Paired t test P values for comparison with baseline are shown for each group. B, Percentage of patients in each ambulation category is shown for baseline and at discharge for each group. Stuart-Maxwell P values comparing postoperative status with baseline are shown for each kyphoplasty group.