Anatomical validation of ultrasound-guided retrolaminar block for the treatment of symptomatic vertebral fragility fractures.

OBJECTIVE: This study aimed to evaluate the anatomical feasibility and the injectate spread pattern of an ultrasound-guided retrolaminar injection in a cadaveric model as a potential approach for targeting the dorsal ramus/medial branch region in patients with symptomatic vertebral fragility fractures (VFs). MATERIALS AND METHODS: Bilateral ultrasound-guided retrolaminar injections were administered at the T9 level in 10 fresh human cadavers. A total of 20 injections were administered using 10 mL of saline solution mixed with 0.02% methylene blue. The distribution of the injectate between the lamina and the erector spinae muscles was assessed both sonographically and through anatomical dissection. RESULTS: In all specimens, dye spread was observed along the retrolaminar plane, extending into the paraspinal region. The craniocaudal spread involved a mean of 5 ± 0.8 vertebral levels. The distribution remained predominantly medial, without consistent extension into the paravertebral, foraminal, or epidural spaces. These findings suggest consistent anatomical access to the retrolaminar region, where the dorsal rami and medial branches are located. CONCLUSION: Ultrasound-guided retrolaminar injection demonstrated consistent anatomical spread of the injectate along the retrolaminar plane in a cadaveric model. These findings support the feasibility of targeting the posterior elements and the dorsal ramus/medial branch region in patients with symptomatic vertebral fragility fractures. Further prospective clinical studies are required to determine the analgesic efficacy, safety, and potential clinical role of this technique in these patients.