Discussion
segmental artery injury, vessel injury, pain, lumbar OVCFs, Roland-Morris disability, thoracic OVCFs
PERIOSTEUM, NERVE ROOT LESION
The most important finding of the present randomized controlled trial was that in patients with lumbar OVCFs, balloon kyphoplasty by unilaterally extrapedicular approach could yield effective pain relief, adequate cement infusion, short operation time, less fluoroscopy exposure, and comparable risk of cement leakage and vessel injury, compared with the procedure by the unilaterally transpedicular approach.The unilaterally extrapedicular approach for kyphoplasty has prevailed over the past years in treating thoracic OVCFs [The cement infiltration by the unilaterally extrapedicular approach brought out additional advantages over the transpedicular approach. In this study, compared to the control group, more cement was injected inside the target vertebral body in the treatment group. We deduce that the achievement of satisfactory cement infusion is highly associated with an advantageous puncture site and angle. In previous studies, several extrapedicular approaches have been proposed. Ryu et al. [The most common concerns about the extrapedicular approach are puncture-related injuries involving segmental artery injury and nerve root lesions. Heo et al. [As all kyphoplasty procedures in this study were carried out by an experienced surgeon, no significant clinical differences have been shown between the two approaches. Actually, the learning curve of the extrapedicular approach is much longer than that of the transpedicular approach for inexperienced practitioners. It will take more time and fluoroscopy to reach the optimal insertion point on the periosteum and verify the occurrence of malposition and cement leakage. As the experience begins to accumulate, the procedure of kyphoplasty by extrapedicular approach could be performed with much shorter time and less fluoroscopy exposure.This study had several limitations. First, the surgeon involved in the surgical procedure was unblinded to participants, which may lead to performance bias. Second, there was no assessment of the quality of life (e.g., Roland-Morris disability questionnaire scores, short-form 36 physical component summary score), which may reach insufficient conclusions. Third, this study compared only unilaterally extrapedicular and transpedicular approaches. The clinical significance would be elevated if the bilaterally transpedicular approach could be taken into comparison.