Effect of posterior decompression extent on biomechanical parameters of the spinal cord in cervical ossification of the posterior longitudinal ligament

Abstract BACKGROUND Surgery for thoracic ossification of the posterior longitudinal ligament (T-OPLL) is still challenging, and factors for good surgical outcomes are unknown. OBJECTIVE To identify factors for good surgical outcomes with prospective and comparative study. METHODS Seventy-one consecutive patients who underwent posterior decompression and instrumented fusion were divided into good or poor outcome groups based on ≥50% and <50% recovery rates for the Japanese Orthopaedic Association score. Preoperative, intraoperative, and postoperative findings were compared in the 2 groups, and significant factors for a good outcome were analyzed. RESULTS Patients with a good outcome (76%) had significantly lower nonambulatory rate and positive prone and supine position tests preoperatively; lower rates of T-OPLL, ossification of the ligamentum flavum, high-intensity area at the same level, thoracic spinal cord alignment difference, and spinal canal stenosis on preoperative magnetic resonance imaging; lower estimated blood loss; higher rates of intraoperative spinal cord floating and absence of deterioration of intraoperative neurophysiological monitoring; and lower rates of postoperative complications (P < .0005). In multivariate logistic regression analysis, negative prone and supine position test (odds ratio [OR]: 17.00), preoperative ambulatory status (OR: 6.05), absence of T-OPLL, ossification of the ligamentum flavum, high-intensity area at the same level (OR: 5.84), intraoperative spinal cord floating (OR: 4.98), and lower estimated blood loss (OR: 1.01) were significant factors for a good surgical outcome. CONCLUSION This study demonstrated that early surgery is recommended during these positive factors. Appropriate surgical planning based on preoperative thoracic spinal cord alignment difference, as well as sufficient spinal cord decompression and reduction of complications using intraoperative ultrasonography and intraoperative neurophysiological monitoring, may improve surgical outcomes.

Download Full-text

Extensive Cervicothoracic Laminoplastic Decompression of the Spinal Cord: A New Method of Posterior Decompression for Thoracic Myelopathy Caused by Ossification of the Posterior Longitudinal Ligament

OPLL ◽

10.1007/978-4-431-67046-9_22 ◽

1997 ◽

pp. 185-192 ◽

Cited By ~ 1

Author(s):

Nobuyuki Tsuzuki ◽

Yasuyoshi Wadano ◽

Shin-ichi Kikuchi

Keyword(s):

Spinal Cord ◽

Posterior Longitudinal Ligament ◽

New Method ◽

Thoracic Myelopathy ◽

Posterior Decompression

Download Full-text

Efficacy of posterior decompression and fixation based on ossification-kyphosis angle criteria for multilevel ossification of the posterior longitudinal ligament in the thoracic spine

Journal of Neurosurgery Spine ◽

10.3171/2017.12.spine17549 ◽

2018 ◽

Vol 29 (2) ◽

pp. 150-156 ◽

Cited By ~ 3

Author(s):

Hiroshi Uei ◽

Yasuaki Tokuhashi ◽

Masashi Oshima ◽

Masafumi Maseda ◽

Masahiro Nakahashi ◽

...

Keyword(s):

Spinal Cord ◽

Vertebral Body ◽

Thoracic Spine ◽

Free Space ◽

Posterior Longitudinal Ligament ◽

Kyphosis Angle ◽

Posterior Decompression ◽

Significant Difference ◽

The Mean ◽

Spinal Cord Decompression

OBJECTIVEThe range of decompression in posterior decompression and fixation for ossification of the posterior longitudinal ligament in the thoracic spine (T-OPLL) can be established using an index of spinal cord decompression based on the ossification-kyphosis angle (OKA) measured in the sagittal view on MRI. However, an appropriate OKA cannot be achieved in some cases, and posterior fixation is applied in cases with insufficient decompression. Moreover, it is unclear whether spinal cord decompression of the ventral side is essential for the treatment of OPLL. In this retrospective analysis, the efficacy of posterior decompression and fixation performed for T-OPLL was investigated after the range of posterior decompression had been set using the OKA.METHODSThe MRI-based OKA is the angle from the superior margin at the cranial vertebral body of the decompression site and from the lower posterior margin at the caudal vertebral body of the decompression site to the prominence of the maximum OPLL. Posterior decompression and fixation were performed in 20 patients. The decompression range was set so that the OKA was ≤ 23° or the minimum if this value could not be achieved. Cases in which an OKA ≤ 23° could and could not be achieved were designated as groups U (13 patients) and O (7 patients), respectively. The mean patient ages were 50.5 and 62.1 years (p = 0.03) and the mean preoperative Japanese Orthopaedic Association (JOA) scores were 5.9 and 6.0 (p = 0.9) in groups U and O, respectively. The postoperative JOA score, rate of improvement of the JOA score, number of levels fused, number of decompression levels, presence of an echo-free space during surgery, operative time, intraoperative blood loss, and perioperative complications were examined.RESULTSIn groups U and O, the mean rates of improvement in the JOA score were 50.0% and 45.6% (p = 0.3), the numbers of levels fused were 6.7 and 6.4 (p = 0.8), the numbers of decompression levels were 5.9 and 7.4 (p = 0.3), an echo-free space was noted during surgery in 92.3% and 42.9% of cases (p = 0.03), the operative times were 292 and 238 minutes (p = 0.3), and the intraoperative blood losses were 422 and 649 ml (p = 0.7), and transient aggravation of paralysis occurred as a perioperative complication in 2 and 1 patient, respectively.CONCLUSIONSThere was no significant difference with regard to the recovery rate of the JOA score between patients with (group U) and without (group O) sufficient spinal cord decompression. The first-line surgical procedure of posterior decompression and fixation with the range of posterior decompression set as an OKA ≤ 23° before surgery involves less risk of postoperative aggravation of paralysis and may result in a better outcome.

Download Full-text

Risk Factors for Ineffectiveness of Posterior Decompression and Dekyphotic Corrective Fusion with Instrumentation for Beak-Type Thoracic Ossification of the Posterior Longitudinal Ligament: A Single Institute Study

Neurosurgery ◽

10.1093/neuros/nyw130 ◽

2017 ◽

Vol 80 (5) ◽

pp. 800-808 ◽

Cited By ~ 17

Author(s):

Shiro Imagama ◽

Kei Ando ◽

Zenya Ito ◽

Kazuyoshi Kobayashi ◽

Tetsuro Hida ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Compression ◽

Supine Position ◽

Posterior Longitudinal Ligament ◽

Cord Compression ◽

Intraoperative Ultrasonography ◽

Posterior Decompression ◽

Motor Paralysis ◽

Severe Motor

Abstract BACKGROUND: Thoracic ossification of the posterior longitudinal ligament (T-OPLL) is treated surgically with instrumented posterior decompression and fusion. However, the factors determining the outcome of this approach and the efficacy of additional resection of T-OPLL are unknown. OBJECTIVE: To identify these factors in a prospective study at a single institution. METHODS: The subjects were 70 consecutive patients with beak-type T-OPLL who underwent posterior decompression and dekyphotic fusion and had an average of 4.8 years of follow-up (minimum of 2 years). Of these patients, 4 (6%; group R) had no improvement or aggravation, were not ambulatory for 3 weeks postoperatively, and required additional T-OPLL resection; while 66 (group N) required no further T-OPLL resection. Clinical records, gait status, intraoperative ultrasonography, intraoperative neurophysiological monitoring (IONM), plain radiography, computed tomography and magnetic resonance imaging findings, and Japanese Orthopaedic Association (JOA) score were compared between the groups. RESULTS: Preoperatively, patients in group R had significantly higher rates of severe motor paralysis, nonambulatory status, positive prone and supine position test, no spinal cord floating in intraoperative ultrasonography, and deterioration of IONM at the end of surgery (P < .05). In preoperative radiography, the OPLL spinal cord kyphotic angle difference in fused area, OPLL length, and OPLL canal stenosis were significantly higher in group R (P < .05). At final follow-up, JOA scores improved similarly in both groups. CONCLUSION: Preoperative severe motor paralysis, nonambulatory status, positive prone and supine position test, radiographic spinal cord compression due to beak-type T-OPLL, and intraoperative residual spinal cord compression and deterioration of IONM were associated with ineffectiveness of posterior decompression and fusion with instrumentation. Our 2-stage strategy may be appropriate for beak-type T-OPLL surgery.

Download Full-text

Resection of Beak-Type Thoracic Ossification of the Posterior Longitudinal Ligament from a Posterior Approach under Intraoperative Neurophysiological Monitoring for Paralysis after Posterior Decompression and Fusion Surgery

Global Spine Journal ◽

10.1055/s-0036-1579662 ◽

2016 ◽

Vol 6 (8) ◽

pp. 812-821 ◽

Cited By ~ 15

Author(s):

Shiro Imagama ◽

Kei Ando ◽

Zenya Ito ◽

Kazuyoshi Kobayashi ◽

Tetsuro Hida ◽

...

Keyword(s):

Spinal Cord ◽

Posterior Approach ◽

Japanese Orthopaedic Association ◽

Posterior Longitudinal Ligament ◽

Intraoperative Neurophysiological Monitoring ◽

Neurophysiological Monitoring ◽

Posterior Decompression ◽

Fusion Surgery ◽

Additional Surgery ◽

Clinical Records

Study Design Prospective clinical study. Objective Posterior decompression and fusion surgery for beak-type thoracic ossification of the posterior longitudinal ligament (T-OPLL) generally has a favorable outcome. However, some patients require additional surgery for postoperative severe paralysis, a condition that is inadequately discussed in the literature. The objective of this study was to describe the efficacy of a procedure we refer to as “resection at an anterior site of the spinal cord from a posterior approach” (RASPA) for severely paralyzed patients after posterior decompression and fusion surgery for beak-type T-OPLL. Methods Among 58 consecutive patients who underwent posterior decompression and fusion surgery for beak-type T-OPLL since 1999, 3 with postoperative paralysis (5%) underwent RASPA in our institute. Clinical records, the Japanese Orthopaedic Association score, gait status, intraoperative neurophysiological monitoring (IONM) findings, and complications were evaluated in these cases. Results All three patients experienced a postoperative decline in Manual Muscle Test (MMT) scores of 0 to 2 after the first surgery. RASPA was performed 3 weeks after the first surgery. All patients showed gradual improvements in MMT scores for the lower extremity and in ambulatory status; all could walk with a cane at an average of 4 months following RASPA surgery. There were no postoperative complications. Conclusions RASPA surgery for beak-type T-OPLL after posterior decompression and fusion surgery resulted in good functional outcomes as a salvage surgery for patients with severe paralysis. Advantages of RASPA include a wide working space, no spinal cord retraction, and additional decompression at levels without T-OPLL resection and spinal cord shortening after additional dekyphosis and compression maneuvers. When used with IONM, this procedure may help avoid permanent postoperative paralysis.

Download Full-text

Intraoperative ultrasonographic evaluation of posterior decompression via laminoplasty in patients with cervical ossification of the posterior longitudinal ligament: correlation with 2-year follow-up results

Journal of Neurosurgery Spine ◽

10.3171/2010.3.spine09680 ◽

2010 ◽

Vol 13 (1) ◽

pp. 47-51 ◽

Cited By ~ 18

Author(s):

Atsushi Seichi ◽

Hirotaka Chikuda ◽

Atsushi Kimura ◽

Katsushi Takeshita ◽

Shurei Sugita ◽

...

Keyword(s):

Spinal Cord ◽

Characteristic Curve ◽

Posterior Longitudinal Ligament ◽

Intraoperative Ultrasonography ◽

Posterior Decompression ◽

First Choice ◽

Maximal Thickness ◽

Type 3

Object The aim in this prospective study was to determine the morphological limitations of laminoplasty for cervical ossification of the posterior longitudinal ligament (OPLL) by using intraoperative ultrasonography and to investigate correlations between ultrasonographic findings and 2-year follow-up results. Methods Included in this study were 40 patients who underwent double-door laminoplasty for cervical myelopathy due to OPLL. Intraoperative ultrasonography was used to evaluate posterior shift of the spinal cord after the posterior decompression procedure. To determine the decompression status of the cord, the authors classified ultrasonographic findings into 3 types on the basis of the presence or absence of spinal cord contact with OPLL after decompression: Type 1, noncontact; Type 2, contact and apart; and Type 3, contact. Patients were divided accordingly into Group 1, showing Type 1 or 2 findings, representing sufficient decompression; and Group 2, showing Type 3 findings with insufficient decompression. Preoperative sagittal alignment of the cervical spine (C2–7 angle) and preoperative maximal thickness of OPLL were compared between groups. The authors also investigated the morphological limitations of laminoplasty and 2-year follow-up results by using the Japanese Orthopedic Association (JOA) scoring system. Results According to receiver operating characteristic curve analysis, an OPLL maximal thickness > 7.2 mm was a cutoff value for insufficient decompression. However, sufficient or insufficient decompression did not correlate with 2-year results, as determined by JOA scores. The C2–7 angle had no impact on ultrasonographic findings. Conclusions Laminoplasty has a morphological limitation for thick OPLLs, and a thickness > 7.2 mm represents a theoretical cutoff for residual cord compression after laminoplasty. According to 2-year results, however, laminoplasty can remain the first choice for any type of multiple-level OPLL.

Download Full-text

Comprehensive Expression Profiles of CircRNAs, LncRNAs, and mRNAs in PBMCs from Patients with Ossification of the Posterior Longitudinal Ligament

Molecular Omics ◽

10.1039/d1mo00060h ◽

2021 ◽

Author(s):

Ning Jiang ◽

Kuibo Zhang ◽

Jie Shang ◽

Bin Wang ◽

Junlong Zhong ◽

...

Keyword(s):

Spinal Cord ◽

Expression Profiles ◽

Posterior Longitudinal Ligament ◽

Spinal Disease ◽

Ectopic Ossification

Ossification of the posterior longitudinal ligament (OPLL), one of spinal disease causing to myelopathy, is characterized by the ectopic ossification and narrowing the spinal cord. However, the pathogenesis of OPLL...

Download Full-text

Cervical myelopathy in patients with ossification of the posterior longitudinal ligament

Journal of Neurosurgery Spine ◽

10.3171/2008.10.spi08480 ◽

2009 ◽

Vol 10 (2) ◽

pp. 122-128 ◽

Cited By ~ 35

Author(s):

Macondo Mochizuki ◽

Atsuomi Aiba ◽

Mitsuhiro Hashimoto ◽

Takayuki Fujiyoshi ◽

Masashi Yamazaki

Keyword(s):

Spinal Cord ◽

Conservative Treatment ◽

Spinal Canal ◽

Clinical Course ◽

Posterior Longitudinal Ligament ◽

Treated Group ◽

Spinal Canal Stenosis ◽

Canal Stenosis ◽

Residual Space ◽

Surgical Group

Object The authors assessed the clinical course in patients with a narrowed cervical spinal canal caused by ossification of the posterior longitudinal ligament (OPLL), but who have no or only mild myelopathy. Additionally, the authors analyzed the factors contributing to the development and aggravation of myelopathy in patients with OPLLinduced spinal canal stenosis. Methods Between 1997 and 2004, the authors selected treatments for patients with cervical OPLL in whom the residual space available for the spinal cord was ≤ 12 mm. Treatment decisions were based on the severity of myelopathy at presentation. Twenty-one patients with no or mild myelopathy (defined as a Japanese Orthopaedic Association [JOA] scale score ≥ 14 points) received conservative treatment, with a mean follow-up period of 4.5 years. In 20 patients with moderate or severe myelopathy (JOA scale score < 14 points), the authors performed surgery via an anterior approach. The clinical course in these patients was assessed with the JOA scale and the OPLL types were classified. The authors evaluated the range of motion between C-1 and C-7, the developmental segmental sagittal diameter, the percentage of spinal canal diameter occupied by the OPLL (% ratio), and the residual space available for the spinal cord on cervical radiographs; T2-weighted MR images were examined for high signal changes (HSCs). Results In the conservative treatment group, 8 patients showed improvement, 12 remained unchanged, and 1 patient's condition became slightly worse during the observation period. Fifteen patients in this group had mixedtype, 3 had continuous-type, 2 had localized-type, and 1 had a segmental-type OPLL. In the surgically treated group, there were 12 patients with segmental-type, 10 patients with mixed-type, and 1 with localized-type OPLL. The mean range of motion at C1–7 was 36.4° in the conservatively treated group and 46.5° in the surgical group (p < 0.05). No significant difference was seen between the groups in terms of developmental segmental sagittal diameter, % ratio, or residual space available for the cord. No HSCs were noted in the conservative group, while 17 patients in the surgical group had HSCs (p < 0.05). Conclusions In the present study, the authors demonstrate that the mobility of the cervical spine and the type of OPLL are important factors contributing to the development and aggravation of myelopathy in patients with OPLLinduced spinal canal stenosis. The authors advocate conservative treatment in most patients with OPLLs who have no or only mild myelopathy, even in the presence of spinal canal narrowing.

Download Full-text