The intravertebral cleft in painful long-standing osteoporotic vertebral compression fractures treated with percutaneous vertebroplasty: diagnostic assessment and clinical significance.

STUDY DESIGN

Prospective follow-up study.

OBJECTIVE

Evaluation of the diagnostic assessment and clinical significance of the intravertebral cleft in painful, long-standing osteoporotic vertebral compression fractures (OVCFs) treated with percutaneous vertebroplasty (PVP).

SUMMARY OF BACKGROUND DATA

Patients with painful OVCFs with intravertebral clefts provide a unique and possibly superior indication for PVP. However, comparative studies are scarce, and the results are conflicting. The extent of the difference attributable to interobserver variation in the identification of an intravertebral cleft is currently unknown.

METHODS

A total of 102 patients received PVP for 197 painful long-standing OVCFs and were prospectively observed, using a pain-intensity numerical-rating scale for back pain, the 36-Item Short Form Health Survey quality-of-life questionnaire, and routine spinal radiographs. Three experienced examiners retrospectively examined all preoperative radiographs and magnetic resonance imaging (MRI) T1-weighted and short-tau-inversion-recovery (STIR) sequences and the direct postoperative computed tomographic scans for the presence of an intravertebral cleft. Disagreements were re-examined and discussed for consensus.

RESULTS

Interobserver agreement for the detection of an intravertebral cleft was moderate on preoperative radiography (κ, 0.55-0.59) and substantial on preoperative MRI (κ, 0.71-0.79) and postoperative computed tomography (κ, 0.67-0.85). On the basis of consensus, 42 (21.3%) clefts were detected. The associated sensitivity of preoperative radiography was low (31.7%-48.8%), but the specificity was high (94.7%-99.3%). The diagnostic performance of preoperative MRI T1-weighted and STIR sequences was excellent, with both high sensitivity (85.7%-88.1%) and high specificity (89.7%-98.1%). Pain decrease and increase in quality of life obtained from PVP were ultimately comparable with patients without intravertebral clefts but was obtained more gradually during the first postoperative year. An intravertebral cleft was a strong risk factor for the occurrence of cortical cement leakage (odds ratio, 4.29; 95% confidence interval, 1.51-12.2; P = 0.006).

CONCLUSION

There is variation between observers in the identification of an intravertebral cleft, and the identification of an intravertebral cleft is not always straightforward. For preoperative assessment, we recommend MRI with T1-weighted and STIR sequences. Regarding patient-reported outcome, patients with long-standing OVCFs with intravertebral clefts benefit from PVP, but, compared with patients with OVCFs without intravertebral clefts, the benefit obtained was not superior and may be delayed.