Noboru Hosono

Neck and shoulder pain after laminoplasty. A noticeable complication.

Study Design The authors retrospectively analyzed the prevalence and features of neck and shoulder pain (axial symptoms) after anterior interbody fusion and laminoplasty in patients with cervical spondylotic myelopathy. Objectives To reveal the difference in prevalence of postoperative axial symptoms between anterior interbody fusion and laminoplasty and to clarify the pathogenesis of axial symptoms after laminoplasty. Summary of Background Data Outcome of the cervical surgery is evaluated on neurologic status alone; axial symptoms after laminoplasty rarely have been investigated. Such symptoms, however, are often severe enough to interfere with a persons daily activity. Methods Ninety‐eight patients had surgery for their disability secondary to cervical spondylotic myelopathy. Of those patients, 72 had laminoplasty, and 26 had anterior interbody fusion. The presence or absence of axial symptoms was investigated before and after surgery. The duration, severity, and laterality of symptoms were also recorded. Results The prevalence of postoperative axial symptoms was significantly higher after laminoplasty than after anterior fusion (60% vs. 19%; P < 0.05). In 18 patients (25%) from the laminoplasty group, the chief complaints after surgery were related to axial symptoms for more than 3 months, whereas in the anterior fusion group, no patient reported having such severe pain after surgery. Conclusions The prevalence and severity of axial symptoms after laminoplasty proved to be higher and more serious than has been believed. Such symptoms should be considered in the evaluation of the outcome of cervical spinal surgery.

C5 palsy after decompression surgery for cervical myelopathy: Review of the literature

Study Design. A literature review was conducted to integrate and compile available reports on postoperative C5 palsy. Objectives. To review the clinical features, possible pathogenesis, and procedures for treatment and prevention of postoperative C5 palsy as a complication of surgery for cervical compression myelopathy. Summary of Background Data. Although postoperative C5 palsy develops in approximately 5% of patients after decompression surgery of the cervical spine, its pathogenesis and the options for prevention and treatment remain unidentified and many controversies exist. Method. We reviewed and analyzed papers published from 1986 to 2002 regarding C5 palsy as a postoperative complication. Statistical comparisons were made when appropriate. Results. Postoperative C5 palsy is reported to occur in an average of 4.6% of patients after surgery for cervical compression myelopathy. No significant differences were noted between patients undergoing anterior decompression and fusion and laminoplasty, nor were distinctions apparent between unilateral hinge laminoplasty and French-door laminoplasty, or between cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament. Two theories were put forth to account for the pathogenesis of C5 palsy: nerve root injury and segmental spinal cord disorder. Neither of these hypotheses has been consistently supported and evidence to refute each hypothesis can be found in the literature. Recently, surgeons have advocated foraminotomy combined with laminoplasty to prevent or treat C5 palsy, but further studies into the efficacy of this procedure are needed. Although patients with C5 palsy generally have a good prognosis for neurologic and functional recovery, those with severe paralysis require significantly longer recovery times when compared to more mild cases. Conclusion. The incidence of postoperative C5 palsy has been reported at 4.6% after surgery for cervical compression myelopathy and this value has not varied with different surgical procedures or disease etiologies. The pathogenesis of postoperative C5 palsy remains unclear at the present time. Patients with postoperative C5 palsy generally have a good prognosis for functional recovery, but the severely paralyzed cases required significantly longer recovery times than the mild cases.

Neurologic Complications of Surgery for Cervical Compression Myelopathy

Neurologic complications resulting from surgery for 384 cases of cervical myelopathy (cervical soft disc herniation, spondylosis, ossification of the posterior longitudinal ligament) were reviewed. Surgical procedures performed included 134 anterior interbody fusions (Cloward or Robinson-Smith technique), 70 subtotal corpectomies with strut bone graft, 85 laminectomies, and 95 lamino-plasties. Twenty-one patients (5.5%) sustained neurologic deterioration related to surgery. The deterioration was classified into two types on the basis of the neurologic signs observed: deterioration of spinal cord function or of nerve root function. Manifestations of the former varied from weakness of the hand to tetraparesis. Paralysis of the deltoid and biceps brachii muscles was an exclusive feature of deterioration in the nerve root group. Causes of this paralysis included malalignment of the spine related to graft complications, and a tethering effect on the nerve root following major shifting of the spinal cord after decompression. The causes of deterioration of the cord function included spinal cord injury during surgery, malalignment of the spine associated with graft complication, and epidural hematoma.

Laminoplasty versus subtotal corpectomy. A comparative study of results in multisegmental cervical spondylotic myelopathy.

A comparative study of surgical results was used to determine the tratment of choice for multisegmental cervical spondylotic myelopathy, forty-one patients who received subtotal corpectomy and strut grafting (SCS) and forty-tow undergoing laminoplasty were followed up for at least 2 years after surgery. Regarding factos known to affect surgical prognosis (age at surgery, duration of symptoms, severity of neurologic deficit, anteroposterior canal diameter, transverse area of the cord at the site of maximum compression, number of levels invoived), the two groups were statistically comparable with each other. The sevenity of neurologic deficits was assessed by the Japaneses Orthopaedic Association scale. Results were evaluated in terms of postoperative score and recovery rate, The difference between the recovery rate and final score between the two groups was not statistically significant. Surgical complications were more frequent in the subtotal corpectomy and strut grafting group than in the laminoplasty group. The most frequent complications encountered in the subtotal corpectomy and strut grafting group were related to bone grafting. Spinal aligment worsened in six patients of the laminoplasty group, but none of them suffered from neurologic deterioration, Another disadvantage of subtotal corpectomy and strut grafting was the longer postoperative period of bed rest needed to secure graft stability. We conclude that laminoplasty should be the treatment of choice for multisegmental cervical spondylotic myelopathy when neurologic results, incidence of complications, and postoperstive treatment are taken into consideration.

Kinematics of the subaxial cervical spine in rotation in vivo three-dimensional analysis

Study Design. Kinematics of the upper cervical spine during head rotation were investigated using three-dimensional magnetic resonance imaging (MRI) in healthy volunteers. Objectives. To demonstrate in vivo intervertebral coupled motions of the upper cervical spine. Summary of Background Data. Although various in vivo and in vitro studies have identified the normal movement patterns of the upper cervical spine, no previous studies have accurately analyzed in vivo three-dimensional intervertebral motions of the upper cervical spine during head rotation. Methods. Fifteen healthy volunteers underwent three-dimensional MRI of the upper cervical spine using a 1.0-T imager in progressive 15° steps during head rotation. Segmented three-dimensional MRIs of each vertebra in the neutral position were superimposed over images taken at other positions, using voxel-based registration. Relative motions between occiput (Oc) and atlas (C1) and between C1 and axis (C2) were measured and described with 6 degrees of freedom by rigid body Euler angles and translations. Results. Mean (± SD) maximum angles of axial rotation in Oc–C1 and C1–C2 were 1.7 ± 1.5° and 36.2 ± 4.5° to each side, respectively. Increases in angle of axial rotation in C1–C2 became smaller with increased head rotation, indicating axial rotation in C1–C2 displayed nonlinear motion. Coupled lateral bending with axial rotation was observed in the direction opposition to that of axial rotation in Oc–C1 (mean, 4.1 ± 1.4°) and C1–C2 (mean, 3.8 ± 3.0°). Coupled extension with axial rotation occurred at both C0–C1 (mean, 13.3 ± 4.9°) and C1–C2 (mean, 6.9 ± 3.0°). Conclusions. We developed an innovative in vivo three-dimensional motion analysis system using three-dimensional MRI. In vivo coupled motions of the upper cervical spine investigated using this system supported the results of the previous in vitro study.

Kinematics of the cervical spine in lateral bending: in vivo three-dimensional analysis.

Study Design. Kinematics of the cervical spine during lateral bending were investigated using a novel system of three-dimensional motion analysis. Objectives. To demonstrate in vivo intervertebral coupled motions of the cervical spine during lateral bending of the neck. Summary of Background Data. No previous studies have successfully documented in vivo three-dimensional intervertebral motions of the cervical spine during lateral bending. Methods. Twelve healthy volunteers underwent three-dimensional magnetic resonance imaging (MRI) of the cervical spine in 7 positions with 10° increments of lateral bending. Relative motions of the cervical spine were calculated automatically by superimposing a segmented three-dimensional-MRI of the vertebra in the neutral position over images of each position using volume registration. Results. Mean maximum lateral bending of the cervical spine to one side was 1.6° to 5.7° at each level. Coupled axial rotation opposite to lateral bending was observed in the upper cervical levels (Oc-C1, 0.2°; C1–C2, 17.1°), while in the subaxial cervical levels, it was observed in the same direction as lateral bending except for at C7–T1. Coupled flexion-extension motion was small at all vertebral levels (<1.1°). Conclusions. We succeeded in identifying in vivo coupled motions of the cervical spine in lateral bending for the first time.

Outcome of total en bloc spondylectomy for solitary metastasis of the thoracolumbar spine.

Background: Total en bloc spondylectomy (TES) was devised to minimize the incidence of local recurrence following resection of spinal tumor. Successful local control with TES has been reported for patients with primary malignant or aggressive benign spinal tumors. As for metastatic spinal tumors, however, only a few surgeons except for the inventor group have reported the outcome of TES. The purpose of this study was to investigate whether TES could provide radical resection of the tumor in patients with solitary spinal metastases. Methods: Twelve patients underwent TES for a solitary metastatic tumor of the thoracolumbar spine. Primary malignancies included breast cancer in four patients, thyroid cancer in three, renal cell carcinoma in three, lung cancer in one, and unknown in one. All patients were regularly followed up with plain radiographs, computed tomography scans, and magnetic resonance imaging to detect local recurrence. Results: In two of the four cases with paraspinal tumor extension, local recurrences developed at 25 months after surgery. Seven patients have survived for an average of 61 months, while the remaining five died of disseminated metastases with a mean survival of 23 months after surgery. Local recurrences were common in patients with paraspinal extensions. TES for lesions with paraspinal extensions failed to provide curative resection of the tumor. Conclusion: Given the great technical demands and potential risks of TES, the indication for TES with spinal metastases should be limited to cases with solitary lesions that do not extend to the paraspinal area.

Vertebral body replacement with a ceramic prosthesis for metastatic spinal tumors

Study Design This study retrospectively analyzed the clinical outcome of vertebral replacement surgery with our unique ceramic prosthesis for spinal metastases. Objectives To indicate the results of vertebral replacement surgery with a ceramic prosthesis. Summary of Background Data Spinal metastasis often involves the vertebral bodies, of which abnormal fracture causes intractable pain and paresis. For such conditions, laminectomy or irradiation can have no effect because they do not improve spinal stability. Autogenous bone or bone cement are not durable materials, and fatigue fracture of the implanted material, occasionally occurs. We developed a simple prosthesis made of alumina ceramic, a bioinert material, to replace the affected vertebrae. There has not been such a large study to assess vertebral replacement surgery with a ceramic prosthesis. Methods From 1972 to 1993, 90 ceramic prostheses were used in 84 patients with spinal metastasis, and the average follow-up period was 28.2 months. The primary tumor was thyroid cancer in 13 patients, breast cancer in 12, multiple myeloma in eight, renal cell cancer in eight, gastrointestinal cancer in eight, and lung cancer in eight. The clinical symptoms were assessed before and after surgery, and the maintenance of operative gain was investigated. Results Pain relief was achieved in 94% motor function improved in 81%, and ambulation recovered in 64%. There were no serious complications associated with the procedure, and the operative benefit was maintained until the terminal stage in the vast majority of patients. Conclusions In selected patients, vertebral replacement using our prosthesis proved to be a useful procedure, effectively managing the severe spinal pain or neurologic deficits associated with vertebral body destruction.

C3-6 laminoplasty takes over C3-7 laminoplasty with significantly lower incidence of axial neck pain

Five-lamina (C3-7) procedure is the most popular cervical laminoplasty and there have been no studies on the most appropriate number of laminae to be opened. We prospectively reduced the range of laminoplasty from C3-7 to C3-6 in 2002 and compared the outcome of C3-6 laminoplasty (n=37) to that of C3-7 laminoplasty (n=28). In both groups, neurological gain was satisfactory, radiographic changes were minimal, and postoperative MRI indicated sufficient expansion of the dura and the spinal cord. Average operating period was significantly shorter, and length of the operative wound was significantly less in the C3-6 group than in the C3-7 group. Postoperative axial neck pain was significantly rarer after C3-6 laminoplasty than after C3-7 laminoplasty (5.4% vs. 29%, P=0.015). Due to its simplicity and various benefits, C3-6 laminoplasty is a promising alternative to conventional C3-7 laminoplasty for treatment of multisegmental compression myelopathy.

Long-term outcome of laminoplasty for cervical myelopathy due to disc herniation : A comparative study of laminoplasty and anterior spinal fusion

Study Design. A retrospective study was conducted. Objective. To compare the long-term outcomes after laminoplasty and anterior spinal fusion (ASF) for cervical myelopathy secondary to disc herniation. Summary of Background Data. There have been no reports of long-term comparative studies of laminoplasty and ASF for cervical myelopathy due to disc herniation. Methods. Of 21 patients who underwent ASF only between 1984 and 1987, 15 were followed up. Of 22 patients who underwent laminoplasty only between 1987 and 1994, 18 were followed up. There were no significant differences in preoperative prognostic factors between the 2 groups. Average follow-up was 15 years in the ASF group and 10 years in the laminoplasty group. Neurologic and radiologic results were examined. Results. Laminoplasty and ASF provided equal neurologic improvement. In the ASF group, additional surgery was required for bone graft complications in 2 patients and for adjacent spondylosis in 1. In the laminoplasty group, one patient had C5 palsy, and intractable axial pain developed in 5 patients after surgery, but no patients needed additional surgery. Conclusions. Because the 2 procedures provided the same neurologic improvement, the risks of bone graft complication with ASF must be weighed against the risks of chronic neck pain associated with laminoplasty for determining the best technique. Therefore, because our present surgical strategy for cervical myelopathy due to disc herniation, laminoplasty is the procedure of choice except for a patient with single level disc herniation without developmental canal stenosis, who is considered to be a good candidate for ASF.