A novel technique to correct kyphosis in cervical myelopathy due to continuous-type ossification of the posterior longitudinal ligament

Abstract

<jats:sec> <jats:title>OBJECTIVE</jats:title> <jats:p>Although posterior decompressive surgery is widely used to treat patients with cervical myelopathy and multilevel ossification of the posterior longitudinal ligament (OPLL), a poor outcome is anticipated if the sagittal alignment is kyphotic (or K-line negative). Accordingly, it is mandatory to perform anterior decompression and fusion in patients with cervical kyphosis. However, it can be difficult to perform anterior surgery because of the high risk of complications. This present report proposes a novel “greenstick fracture technique” to change the K-line from negative to positive in patients with cervical myelopathy, OPLL, and kyphotic deformity.</jats:p></jats:sec> <jats:sec> <jats:title>METHODS</jats:title> <jats:p>Four patients with cervical myelopathy, continuous-type OPLL, and kyphotic sagittal alignment (who were K-line negative) were indicated for surgery. Posterior laminectomy and lateral mass screw insertions using a posterior approach were performed, followed by anterior surgery. Multilevel discectomy and thinning of the OPLL mass by bur drilling was performed, then an intentional greenstick fracture at each disc level was made to convert the cervical K-line from negative to positive. Finally, posterior instrumentation using a rod was carried out to maintain cervical lordosis.</jats:p></jats:sec> <jats:sec> <jats:title>RESULTS</jats:title> <jats:p>MRI showed complete decompression of the cord by posterior migration in all cases, which had been caused by cervical lordosis. Restoration of neurological defects was confirmed at the 1-year follow-up assessment. No specific complications were identified that were associated with this technique.</jats:p></jats:sec> <jats:sec> <jats:title>CONCLUSIONS</jats:title> <jats:p>A greenstick fracture technique may be effective and safe when applied to patients with cervical myelopathy, continuous-type OPLL, and kyphotic deformity (K-line negative). However, further studies with more cases will be required to reveal its generalizability and safety.</jats:p></jats:sec>

Review of Radiological Parameters, Imaging Characteristics, and Their Effect on Optimal Treatment Approaches and Surgical Outcomes for Cervical Ossification of the Posterior Longitudinal Ligament

“…Moreover, some researchers have suggested that dynamic factors stimulate the progression of OPLL, and stabilization of the range of motion can reduce the progression of OPLL. [54][55][56][57][58][59] There are options for posterior decompression and fixation if it is difficult to directly remove OPLL by the anterior approach for any reason, especially when combined with kyphosis. Katsumi et al 59 evaluated whether laminoplasty with instrumented fusion (posterior decompression and fusion [PDF] group) suppresses the progression of OPLL in comparison with stand-alone laminoplasty (LP group), using their novel OPLL volume analysis with 3-dimensional CT.…”

Anterior controllable antidisplacement and fusion surgery for the treatment of multilevel severe ossification of the posterior longitudinal ligament with myelopathy: preliminary clinical results of a novel technique

“…The posterior decompression surgery can safely achieve the decompression of the spinal cord that results from extensive OPLL. However, there are limitations in posterior decompression surgery, it does not always produce the expected space for cases with a highly narrowed spinal canal or a bad lordosis [16,17]. Furthermore, the posterior decompression surgery is accused of higher incidence of C5 palsy, postoperative kyphotic change, and postoperative progression of the ossified OPLL lesion in many studies [18][19][20].…”

Consensus statement on diagnosis and treatment of cervical ossification of posterior longitudinal ligament from Asia Pacific Spine Society (APSS) 2020

“…Then anterior surgery can be added priorly to correct the curvature. 51 The combined approach can be performed in one-stage or two-stages. Though it combines the advantages of direct and indirect decompressions, its high risk should be paid attention.…”