Spinous Process-splitting Laminoplasty Research Articles

Midline spinous process splitting laminoplasty in a newborn with thoracolumbar epidural hematoma: a bone-sparing procedure based on anatomy and embryology.

Spinal epidural hematoma (SEH) is a rare condition leading to spinal cord compression after trauma, surgery, or other. In 40% of the cases, the cause is unknown or unidentified. Due to the absence of specific symptoms, the diagnosis is often delayed. The mainstay of treatment is urgent evacuation of the hematoma. The choice of the surgical technique is surgeon-dependent and ranges from simple decompression and hematoma evacuation to variable combinations of decompression and reconstruction of the posterior spinal arch. To our knowledge, we describe the youngest case in the literature of a thoracolumbar SEH in a newborn with hemophilia A which was evacuated by spinous process splitting laminoplasty (SPSL). SPSL was chosen to avoid damaging the primary ossification centers, preserve the paravertebral musculature, and evade the sequelae of multilevel laminectomies. In our opinion, this technique should be propagated in the pediatric population for accessing the posterior and posterolateral spinal canal.

Impact of cervical sagittal parameters and spinal cord morphology in cervical spondylotic myelopathy status post spinous process-splitting laminoplasty.

No standard strategy exists for managing cervical spondylotic myelopathy (CSM). The efficacy of spinous process-splitting laminoplasty, its impact on cervical alignment change and the incidence of postoperative neck pain remain unclear. We analyzed the parameters of cervical alignment and cord morphology in CSM. The radiographic parameters investigated were pre- and postoperative C2-C7 lordosis (CL), C2-C7 sagittal vertical axis (CSVA), T1 slope (TS), TS minus CL (TS - CL) and cervical spinal cord morphology. Myelopathy severity was measured using two different functional scores. Statistical analysis was performed to determine significant differences between preoperative and follow-up radiological findings and change in functional scores. This retrospective study comprised 85 CSM patients from a single institute, with a minimum follow-up of 24months. Overall, 63.5% (n = 54) of patients had improvement in their postoperative cervical lordotic alignment; 36.5% (n = 31) developed progressive aggravation of the cervical kyphotic alignment. Pearson correlation analysis showed that CSVA, TS and T1-CL were independent predictors of CL curve change. Based on the receiver operating characteristic curve, the cutoff value for CSVA was 2.89cm with a postoperative visual analog scale (VAS) > 4. The cutoff value of the TS - CL was 20 degrees with a postoperative VAS > 4. CSVA, TS and TS - CL had a significant association with variation in CL. CSVA and TS - CL had a significant association with postoperative neck pain. CSVA, T1 slope and T1-CL are good predictors of postoperative degenerative kyphotic change and neck pain. Careful consideration of their preoperative cutoff values can improve postoperative outcomes. IV. These slides can be retrieved under Electronic Supplementary Material.

Cervical Laminoplasty: The History and the Future.

Cervical laminoplasty was developed as an alternative to cervical laminectomy for treatment of cervical myelopathy, in which hinges are created to lift the lamina. Various techniques of laminoplasty have since been developed after two prototype techniques: Hirabayashi’s open-door laminoplasty and Kurokawa’s spinous process splitting (double-door) laminoplasty. Several in vitro studies report superior biomechanical stability of the cervical spine after laminoplasty compared with laminectomy. In clinical situation, randomized control studies are scarce and superiority of one procedure over another is not uniformly shown. Lack of hard evidence supporting the purported advantages of laminoplasty over laminectomy, that is, reduced rate of postoperative instability and kyphosis development, while preserving range of motion (ROM), has been a weak selling point. Currently, laminoplasty is performed by majority of spine surgeons in Japan, but is rarely performed in the United States and Europe. Recent development in laminoplasty is preservation of muscle attachment, which enabled dynamic stabilization of the cervical spine by neck extensor muscles. After treatment with new laminoplasty techniques with active postoperative neck ROM exercises, postoperative instability, kyphosis, axial neck pain, and loss of ROM seems minimal. Well-designed clinical trials to show the effectiveness and long-term outcome of this surgical procedure are warranted.

Use sagittal reconstruction CT for making decisions regarding the surgical strategy for cervical ossification of the posterior longitudinal ligament

Use sagittal reconstruction CT to verify the surgical strategy for cervical ossification of the posterior longitudinal ligament (OPLL). A retrospective study of 161 patients (106 males and 55 females) who had undergone surgery for OPLL from July 2007 to November 2010 was performed. The mean age at surgery was 54.5 years (range from 26 to 77 years). The mean follow-up period was 28 months (12 - 54 months). There were 40 patients accept anterior approach surgeries (anterior group) which include 14 cases of anterior cervical corpectomy and fusion and 26 cases of anterior cervical discectomy and fusion. There were 120 patients accept posterior approach surgeries (posterior group) which was spinous process-splitting laminoplasty for cervical myelopathy using coralline hydroxyapatite. One patient accepted combined anterior and posterior approach. According to the sagittal reconstruction CT, the main reason for spinal cord compression was cervical disc herniation in anterior group, and OPLL in posterior group. The level of spinal cord compression was 1 to 2 levels in anterior group, and 1 to 5 levels in posterior group with a major of 2 to 4 levels. As the classification of OPLL, segmental type and circumscribed type were major of segmental type in anterior group and all of the four types were in posterior group, the distribution of each type was average. The patients of posterior group were classified into two groups according to the modified K-line classification, and clinical results were compared between the two groups. The modified K-line was defined as a line that connects the midpoints of the spinal canal at C(2) and C(7) on sagittal CT myelography. Compression to the spinal cord did not exceed the K-line in the modified K-line(+) group and did exceed it in the modified K-line(-) group. Clinical data were compared using t-test or χ(2) test. Correlation analysis was used to determine the relationships of C(2)-C(7) angulation between sagittal reconstruction CT and neutral position X-ray. The patient of anterior group had better recovery rate of the JOA score (72% ± 27%) than the posterior group (59% ± 35%) at the latest follow-up (t = 2.238, P = 0.027). In posterior group, the patients of modified K-line(+) group had better recovery rate of the JOA score (63% ± 37%) than the K-line(-) group (49% ± 30%) at the latest follow up (t = 2.150, P = 0.034). The C(2)-C(7) angulation on sagittal reconstruction CT was 11° ± 9° which has significantly correlated with the C(2)-C(7) angulation on neutral position X-ray which was 10° ± 10° (r = 0.947, P < 0.01). Considering the selection of surgical approach, it should be combined with the main clinical diagnosis for spinal cord compression, the level of compression, the classification of OPLL and the kyphotic alignment of the cervical spine. The modified K-line is a simple and practical tool for making decisions regarding the surgical strategy for cervical OPLL patients.

A case of retroodontoid pseudotumor after cervical spinous process-splitting laminoplasty

A case of retroodontoid pseudotumor after cervical spinous process-splitting laminoplasty

An ultrastructural study on the ligamentum flavum of the cervical spine in patients with ossification of the posterior longitudinal ligament

Some histological analyses of the ossification of the posterior longitudinal ligament (OPLL) have been reported, but no ultrastructural studies of the ligamentum flavum (LF) in patients with OPLL have been published to date. To understand the pathology of the ossification of the spinal ligament, we examined, by electron microscopy, ultrastructural changes in the LF in cases of OPLL and made a comparison with the LF in cervical spondylotic myelopathy (CSM). Subjects were three men and two women with cervical OPLL who underwent longitudinal spinous process-splitting laminoplasty. During surgery, a small piece of the LF was collected from C2-C3 to C7-T1 and was then analyzed by light and electron microscopy. We observed atrophic elastic bundles with a two-layer structure and disarrangement, a partially torn area, the disappearance of microfibrils, and an enlarged interstitium with an irregular alignment of collagen fibrils. We observed some properties of a cell preceding its death: the initial phase may be the disappearance of the plasma-membrane, followed by the scattering of many organellae around its degenerated nucleus. Finally, many extracellular plasma membrane-invested particles that resemble matrix vesicles remain there without phagocytosis. These results suggest that ultrastructural abnormalities exist in the spinal ligament in cases of ossification of the spinal ligament.

Prediction of Spinal Canal Expansion Following Cervical Laminoplasty: A Computer-Simulated Comparison Between Single and Double-Door Techniques

Laminoplasty was simulated using a computer-assisted technique to assess the amount of canal expansion. This study was designed to clarify the relationship between laminoplasty opening size and increase in sagittal canal diameter, increase in canal area, and the angle of the opened lamina following laminoplasty, and to determine whether a spinous process-splitting laminoplasty achieves the similar canal expansion as a single open-door method. Single and double-door cervical laminoplasty (SDCL and DDCL, respectively) have been widely used in the treatment of multilevel stenotic conditions. However, the relationship between laminoplasty opening size and spinal canal expansion following laminoplasty, and the comparison of postoperative spinal canal expansion between single and double-door techniques have not been well investigated. SDCL and DDCL, based on preoperative computerized tomography scans of 34 patients who had undergone the laminoplasty surgery, were simulated using a computer-assisted technique. Laminoplasty with an opening size of 6, 8, 10, 12, 14, 16, and 18 mm were simulated to determine the amount of canal enlargement with the various opening size. Sagittal diameter, canal area, and lamina angle were increased steadily following either single or double-door laminoplasty with the door opened from 6 to 18 mm. Significant positive correlation was found between laminoplasty opening size and increase in sagittal diameter (R2 = 0.969 and P = 0.001 in SDCL; R2 = 0.926 and P < 0.001 in DDCL), increase in canal area (R2 = 0.961 and P < 0.001 in SDCL; R2 = 0.937 and P < 0.001 in DDCL), and lamina angle (R2 = 0.959 and P < 0.001 in SDCL; R2 = 0.943 and P < 0.001 in DDCL). No significant correlation was observed between preoperative sagittal diameter and increase in sagittal diameter of the spinal canal, whereas significant positive correlation was found between preoperative cross-section area and increase in cross-section area of the spinal canal. The differences between postoperative canal increase in sagittal diameter and canal area for the single versus double-door technique were statistically significant when the door was opened by more than 12 mm (P < 0.05). Our investigation provides insight into canal expansion after laminoplasty. The increased amount of canal following laminoplasty can be predicted by the regression equations. This may allow preoperative determination of the optimal size of the opening needed to establish adequate canal space for the spinal cord. Both single and double-door techniques of laminoplasty provide sufficient room for posterior migration of the spinal cord, although gaining different canal expansion.

Kinetic Analysis of the Cervical Spinal Cord in Patients After Spinous Process-Splitting Laminoplasty Using a Kinematic Magnetic Resonance Imaging Technique

An in vivo flexion-extension magnetic resonance imaging study. To evaluate the kinetic changes of the cervical spinal cord after laminoplasty in patients with cervical myelopathy. Laminoplasty for cervical myelopathy increases the space occupied by the spinal cord, leading to a decompressive effect on the cord. However, there are few reports on kinetic changes of the spinal cord following this surgical procedure, by which it may contribute to an improvement of clinical symptoms. Patients who underwent spinous process-splitting laminoplasty (n = 40) and control group (n = 20) were enrolled in the study. Cervical spines of the subjects were examined from maximum extension to maximum flexion using a magnetic resonance imaging scanner. Sagittal T1-weighted images were obtained at 12 different angle positions. Images were analyzed with respect to the distance and alignment disparity between the dorsal edge of the vertebral column and the center of the cord at each disc level using National Institutes of Health Image software. Spinal cords of patients after laminoplasty were dorsally shifted in the enlarged spinal canal at neutral, extension, and flexion positions. Alignment changes of the cord during flexion-extension movements of the cervical spine were dissociated from those of the vertebral column because of smaller changes in the cord alignment. Spinous process-splitting laminoplasty increases the degree of freedom of the spinal cord.

Investigation of axial symptoms after cervical laminoplasty, using questionnaire survey

Background context Cervical laminoplasty is a good strategy for cervical myelopathy, but some postoperative patients complain of obstinate axial symptoms after surgery, that is, nuchal pain, neck stiffness, and shoulder pain. It was reported that these symptoms proved to be more serious than has been believed and should be considered in the evaluation of the outcome of cervical spinal surgery. However, axial symptoms are sometimes recognized before surgery, or also after corpectomy. Addressing this issue becomes complicated. Purpose We investigate the difference in axial symptoms before and after laminoplasty and discuss the characteristics of these symptoms as a surgical complication. Study design/setting We conducted a questionnaire survey and reviewed the medical records of respondents. Patient sample All of the 180 patients who underwent a spinous process-splitting laminoplasty for cervical myelopathy caused by degenerative disease in our institution from 1993 until 2002 and were followed for 2 years or longer after surgery. Outcome measures Self-report measures and functional measures. The questionnaire elicited information as follows: the location and characteristics of pre- and postoperative symptoms, frequency and duration of postoperative symptoms, and impairment in activities of everyday living, analgesic use, and the duration of use of cervical orthosis after surgery. Methods We divided axial symptoms into four characteristics based on previous reports: “pain,” “heaviness,” “stiffness,” and “other.” An illustration of the upper back on which respondents could mark each characteristic was utilized to acquire information about the location of axial symptoms. The following information was gathered from medical records and statistically analyzed: whether postoperative axial symptoms were related or not, age, sex, neurological findings, the period of cervical orthosis, surgery time, blood loss, with or without reconstruction surgery of the semispinalis cervicis muscle, and preoperative axial symptoms. Results For all of the 51 respondents, the average time since surgery was 4.1 years at the time of investigation; 42 patients complained of postoperative axial symptoms; 26 patients stated the duration of symptoms after surgery to be “more than 2 years.” The surgical outcome of this group, however, did not differ from that of the 2-year-or-less group. Axial symptoms, which accounted for 13.3% of all answers about postoperative impairment of everyday living, were similar to hand numbness. Of respondents with postoperative axial symptoms, 52.2% stated the frequency of affliction to be “all day long,” but 34.8% replied “rarely” to frequency of use of analgesics. Axial symptoms in the nuchal region increased from 45.2% to 48.6% after surgery. “Stiffness” was the most common characteristic before and after surgery, but “pain” significantly increased from 24.6% before surgery to 38.4% after surgery. We speculate that the principal manifestation of axial symptoms might be pain and that the nuchal region might be the predominant region for axial symptoms. There was no significant difference in age, blood loss, operative time, sex, duration of use of cervical orthosis, reconstructive surgery, and preoperative symptoms between two groups—those who complained of` axial symptoms after surgery, and those who did not. Conclusions In this survey, axial symptoms were not usually so severe as to require analgesic use and did not worsen the Japanese Orthopaedic Association score after surgery; symptoms were, however, considered to continuously affect everyday life as much as hand numbness. Regarding their features, we speculate the main characteristics of axial symptoms might be pain and that the nuchal region might be the predominant region for axial symptoms. Our data are consistent with the hypothesis that laminoplasty is not, as such, an effective treatment for axial neck pain and that axial symptoms may in fact be worsened by the procedure.

Cervical posterior laminoplasty operation using coralline hydroxyapatite

To study the results of using coralline hydroxyapatite (CHA) in cervical posterior laminoplasty operation. Two hundred and fifty-six patients underwent cervical spinous process-splitting laminoplasty using CHA. All patients had been followed up over 3 months. One hundred and forty-two patients were followed up at least 2 years. All patients had spinal stenosis at least at 3 levels or OPLL. The average follow up time was 34.6 months. The CHA grafts were stable between the split spinous processes. The union rate of CHA was 83.5%. After operation, the spinal cord moved dorsally, and the anteroposterior compression ratio had been improved from 0.19 to 0.42. No apparent kyphosis occurred. The JOA score improvement rate was 58.3%. There were 24 patients (17%) with axial symptom. Cervical posterior laminoplasty operation using coralline hydroxyapatite may achieve good results.

正中縦割式と片開き式椎弓形成術の比較

正中縦割式と片開き式椎弓形成術の比較

頚椎黄色靭帯石灰化症を合併した脊髄症の１例

We report a case of a 76-year-old man with cervical spondylotic myelopathy acconpanied by calcification of the ligamentum flavum. The patient complained of numbness with bilateral fingers and precise motion disturbance a year and a half ago, and expressed conspicuous spastic gaits three months ago. MRI scanning showed spinal canal stenosis and CTM revealed calcification of the ligamentum flavum especially at C3/4. We performed spinous process-splitting laminoplasty, which decreased their symptoms.Under a scanning electron microscope, we examined the surgical specimen extracted from the ligamentum flavum. It included shaped crystalline structures extensively. Results of chemical composition analysis suggested crystal as calcium pyrophosphate dihydrate (CPPD), but did not confirm the existence of hydroxyapatites (HAP).

Does reconstruction of posterior ligamentous complex with extensor musculature decrease axial symptoms after cervical laminoplasty?

The authors retrospectively determined the prevalence of neck and shoulder symptoms (axial symptoms) after expansive laminoplasty with reattachment of spinous process and extensor musculature in patients with cervical myelopathy. To determine the prevalence of both preoperative and postoperative axial symptoms of expansive laminoplasty when they occur after expansive laminoplasty. Several clinical reports have noted that laminoplasty for cervical myelopathy produces positive clinical outcomes. However, recent reports have pointed out that complications from laminoplasty, such as axial symptoms, may be severe enough to interfere with daily activities. The authors used a modified spinous process-splitting laminoplasty, which involved reattaching the spinous process with extensor musculature after enlarging the spinal canal by use of the French window method. Postoperative axial symptoms were investigated in 173 of 214 patients (80.1%) who underwent expansive laminoplasty between January 1989 and December 1998. The patients included 121 men and 52 women, and their average age was 61.5 years. The presence or absence and grade of axial symptoms before and after laminoplasty were investigated. The severity and duration of complications were also recorded, along with differences between age, sex, spinal alignment, and cervical diseases. Neck and/or shoulder stiffness worsened in 15% of the patients and declined in 21%. Neck pain worsened in 10% of the patients and improved in 11%. Neck and/or shoulder stiffness worse than moderate was recognized in 14.4% of the patients. Neck pain worse than moderate was recognized in 5% of the patients. In the 137 patients who had no axial pain before surgery, only 13 patients experienced such symptoms after surgery, and in most cases these symptoms were minimal. In only 1 case, significant postoperative neck pain arose de novo as a result of this surgery. In 88 patients who had no neck and/or shoulder stiffness before surgery, only 16 patients experienced such symptoms after surgery, and in most cases these were minimal. A similar pattern held true for each of the other grades of preoperative axial symptoms. The recovery rate score (Japanese Orthopedic Association) was 47.5 +/- 32.3 in the patients whose axial symptoms were worse than moderate and 60 +/- 28.9 in patients whose axial symptoms were less than mild. This difference was significant (P < 0.05). Laminoplasty is an appropriate operation for cervical spondylotic myelopathy and did not, in this study, seem to have any significant influence on the development or resolution of axial symptoms.

T-Saw laminoplasty for the management of cervical spondylotic myelopathy: clinical and radiographic outcome.

Independent evaluation of 18 patients with multilevel cervical spondylotic myelopathy who underwent threadwire T-saw laminoplasty. Assess the efficacy of midline T-saw laminoplasty in non-Japanese patients based on clinical and radiographic criteria. Spinous process-splitting laminoplasty has been well accepted in Japan. The results in non-Japanese patients are unknown. A single physician performed independent clinical and radiographic evaluations at latest follow-up (mean, 24 months). In addition to a patient self-assessment questionnaire, objective measures included physical examination, Pavlov's ratio, sagittal canal diameter (by computed tomography), cord compression index, cervical lordosis, range of motion, and complications. Progression of myelopathy was arrested in all patients. Patients reported improvement in strength (78%), dexterity (67%), numbness (83%), pain (83%), and gait (67%). Bowel and bladder compromise resolved in five of six patients. The mean Nurick score improved from 2.7 to 0.9 (P < 0.001), and the mean Robinson pain score improved from 2.0 to 0.89 (P = 0.002). No patient required narcotic analgesics at latest follow-up compared with eight before laminoplasty. Objectively, 68% of patients with motor weakness regained normal strength (P = 0.001), whereas 50% regained normal sensation (P = 0.003). Radiographic canal expansion was verified by a statistically significant increase in the mean Pavlov ratio and osseous sagittal computed tomographic measurements. The mean cord compression index improved from 0.49 to 0.61 (P = 0.01). There was no significant change in mean cervical lordosis. Graft dislodgment or segmental instability did not occur. Complications included: infection (n = 1) and persistent postoperative motor root lesion at C5 (n = 1). T-saw laminoplasty appears to be a safe and effective method of arresting the progression of myelopathy and allowing marked functional improvement in most patients with multilevel cervical spondylotic myelopathy. [Key Words: cervical spine, decompression, laminoplasty, myelopathy, spondylosis]

The Results of Spinous Process-splitting Laminoplasty Using Heterograft Spinous Process Spacer

The Results of Spinous Process-splitting Laminoplasty Using Heterograft Spinous Process Spacer

血液透析患者における頚椎黄色靭帯石灰化症の２症例

This report describes two hemodialysis patients with cervical myelopathy due to calcification of the ligamentum flavum. The patients were male aged 59 and 57 who had been hemodialysed for 2 years and 3 months, and 22 years respectively. Their chief complaint were gait and precise motion disturbance. Computed tomography after myelography clearly showed the calcified lesion of the yellow ligament, which markedly compressed the spinal cord. We performed spinous process-splitting laminoplasty, which decreased their symptoms.Certain hypotheses were studied in the previous report on the causes of the calcification of the ligamentum flavum; for example mobile stress of the yellow ligament, estrogen decrease, and calcium metabolism disorder. Hemodialysis causes calcium metabolism disorder and calcium deposit to soft tissues like the periarticulation, vasculum and subcutis. There has however been no report on the observation of calcification at the yellow ligament.We believe that hemodialysis which causes calcium metabolism disorder is related to the calcification of the ligamentum flavum.

超音波骨メスを利用した棘突起縦割式頚部脊柱管拡大術 : 超音波骨メスの有用性について

超音波骨メスを利用した棘突起縦割式頚部脊柱管拡大術 : 超音波骨メスの有用性について

Expansive Midline T-Saw Laminoplasty (Modified Spinous Process-Splitting) for the Management of Cervical Myelopathy

The authors developed a method of spinous process-splitting laminoplasty using a threadwire saw in a prospective study of 25 patients with cervical myelopathy. This report describes the surgical technique and the results of the expansive midline laminoplasty performed with an threadwire saw. To compare the efficacy of midline, threadwire-saw laminoplasty with that of the original spinous process-splitting laminoplasty. The spinous process-splitting laminoplasty was described by Kurokawa in 1982. Although the procedure has a number of theoretical and practical advantages, it has not been widely used because of technical difficulties. Twenty-five patients who underwent expansive, midline, threadwire-saw laminoplasty from C3 to C7 for cervical myelopathy were studied. The threadwire saw was used to split the spinous processes. The mean follow-up period was 34 months. Neurologic results were evaluated with pre- and postoperative scores, and recovery rates were evaluated by methods described in previous reports using the Japanese Orthopaedic Association scoring system. Radiographic data analyzed included plain radiographs and computed tomography scans. The duration of surgery and the amount of blood lost during this procedure using the threadwire saw were compared with the duration and blood loss that occurred during the original Kurokawa's procedure using a burr. In all cases, good enlargement of the cervical canal was achieved. The mean increase in cervical cross-sectional area was 36.1%, according to computed tomography scans. No dural tears occurred, and no patients experienced any decrease in neurologic function. The neurologic recovery rate was 72%, which was almost same as the neurologic recovery rate in the original procedure. Using the threadwire saw, the mean duration of surgery was 63 minutes shorter and the mean blood loss was 70 cc less than in procedures using burrs. The application of the threadwire saw to split the spinous processes made Kurokawa's procedure simpler, faster, and safer.

Spinous Process-splitting Laminoplasty with an Extended Foraminotomy for Cervical Myelopathy

Spinous Process-splitting Laminoplasty with an Extended Foraminotomy for Cervical Myelopathy

Spinous process-splitting laminoplasty with an extended foraminotomy for cervical myelopathy.

We present the surgical results of a laminoplasty with an extended foraminotomy for cervical myelopathy. We chose spinous process-splitting laminoplasty, because it gave us the opportunity to perform bilateral foraminotomies through the same exposure. An extended foraminotomy means that root decompression is performed as far laterally as possible, using the surgical microscope. We performed this method in 18 patients and experienced favorable clinical results. Neuroradiological evaluations revealed good decompression of the spinal cord postoperatively. Although the operation time needed was longer compared with the original method, the average blood loss was 430 ml and blood transfusion was necessary in five patients. This method can be considered when cervical myelopathy is treated by a posterior approach.