Posterior Decompression and Fusion with Vertical Pressure Procedure in the Treatment of Multilevel Cervical OPLL with Kyphotic Deformity.

OBJECTIVE

To report the outcomes and feasibility of a new technique to change K-line (-) to K-line (+) via only a posterior approach to treat multilevel non-continuous cervical ossification of the posterior longitudinal ligament (C-OPLL) with kyphotic deformity.

METHODS

In this study, 17 consecutive cases of patients who underwent vertical pressure procedure (VP) combined with posterior cervical single-open-door laminoplasty and instrumented fusion from January 1, 2017 to December 31, 2019 were enrolled. The following radiographic parameters: C2-C7 Cobb angle, local Cobb angle, extent of OPLL, and the distance from OPLL to the K-line(DK) were measured and analyzed. Clinically, the JOA score, VAS-N and VAS-A, NDI, and complications were collected from medical records to evaluate the clinical outcomes.

RESULTS

All 17 cases shifted from K-line (-) to K-line (+).Comparing the preoperative images to the final follow-up images, the mean C2-7 Cobb angle changed from -6.94° ± 8.30° to 8.18° ± 4.43°, and the local Cobb angle altered from -9.12° ± 8.68° to 6.65° ± 6.11°. The mean DK increased from -2.64 ± 1.52 mm to 3.09 ± 2.19 mm. One patient showed C5 palsy and recovered within 3 months. The mean JOA score increased from 8.88 ± 2.11 to 14.71 ± 1.36. The average NDI decreased from 20.65 ± 7.80 to 8.94 ± 4.93. The mean VAS-N and VAS-A decreased from 3.44 ± 1.80 and 4.69 ± 1.97 to 1.25 ± 0.86 and 1.38 ± 1.16. All patients were followed up for at least 1 year.

CONCLUSION

A new technique added to posterior decompression and fusion (PDF), the vertical pressure procedure effectively corrects K-line (-) to K-line (+) and avoids the shortcomings of conventional anterior decompression and fusion (ADF) as well as PDF to provide a relatively safe and adequate decompression, cervical realignment. It pronounced satisfactory clinical outcome for extensive non-continuous OPLL with kyphotic deformity even though OPLL remains ventral to the spinal cord.