Disc associating axial pain were indicated by PLL resection in ACDF surgery

The generation and tissue origination of disc-associated axial pain is still under exploration. This study was performed to evaluate disc-associated axial pain and to explore whether it originates in the disc or its surrounding components.

A 6-year series of 88 single-level Smith-Robinson disc and posterior longitudinal ligament (PLL) resections performed to treat single-level cervical spondylotic myelopathy was retrospectively examined. All single-level anterior disc decompressions were performed under local infiltration anesthesia; the PLL was not anesthetized to avoid cervical cord block. The patients were grouped by disc level. The centered foci of the pain localization were subjectively recorded before, during, and after the operation. Radiological examinations (plain X-ray, computed tomography, and magnetic resonance imaging) were performed before and after the operation to diagnose the compression and evaluate the decompression.

All 88 patients who underwent single-level PLL resection had no intraoperative pain responses except during resection of the PLL. Their provoked pain responses were similar to their familiar pain responses. The axial pain disappeared postoperatively. Complications developed in six patients (6.8 %). All patients recovered well, and the absence of the axial pain was maintained at the 12-month follow-up.

Preoperative axial pain due to single-level disc protrusion was triggered and aggravated only during PLL resection and disappeared postoperatively. This implies that the intervertebral PLL could be the site of origination of axial pain. Axial pain from the PLL at different disc levels had different distributions.