A less-invasive cervical laminoplasty for spondylotic myelopathy that preserves the semispinalis cervicis muscles and nuchal ligament.

OBJECT: Modified cervical laminoplasty techniques have been developed to reduce postoperative axial neck pain and preserve function in patients with cervical spondylotic myelopathy (CSM). However, the previous studies demonstrating satisfactory surgical outcomes had a retrospective design. Here, the authors aimed to prospectively evaluate the 2-year outcomes of a modified cervical laminoplasty technique for CSM that preserves the paravertebral muscles. METHODS: Outcomes were analyzed for 40 patients (22 men and 18 women; mean age, 66.6 years; age range 44-92 years) with CSM who underwent C4-6 laminoplasty with C-3 and C-7 partial laminectomies or C-3 total and C-7 partial laminectomies and received hydroxyapatite spacers. Neurological, pain severity, and spinal radiographic evaluations were performed preoperatively and at 3, 6, 12, 18, and 24 months postoperatively. Plain radiography and MRI of the cervical spine were performed to evaluate the range of motion (ROM), sagittal alignment, and cross-sectional areas of the deep extensor muscles. The extent of bone-spacer bonding and bony union at the gutter was assessed by CT. RESULTS: The mean preoperative Japanese Orthopaedic Association CSM score was 10.2, but it increased to 14.4 by 24 months after surgery. Eleven patients had axial neck pain preoperatively, but only 3 reported mild pain at 24 months, and in all 3 cases the pain was mild. The mean angle of lordosis was 11.7° preoperatively and 12.0° 2 years postoperatively. Although the ROM at the C2-7 levels was significantly reduced 3 months postoperatively, an increasing trend was observed up to 12 months, and 86% of the preoperative ROM was achieved by 2 years postoperatively. The mean paravertebral muscle cross-sectional areas were 833 ± 215 mm(2) preoperatively and 763 ± 197 mm(2) 24 months postoperatively, but the difference was not statistically significant. The rates of bone-spacer bonding and bony union at the gutter were low during the early stages but increased to 90% and 93%, respectively, by 2 years after surgery. CONCLUSIONS: The modified laminoplasty technique used in this study ensured very good neurological status and ROM after 2 years and was associated with low incidences of axial neck pain and serious complications. This simple and easy operative method could benefit future laminoplasty protocols.

Activation of rat nucleus pulposus cells by coculture with whole bone marrow cells collected by the perfusion method.

Cell proliferation and matrix synthesis were compared for rat nucleus pulposus cells cocultured with mesenchymal stem cells (MSCs) or fresh whole bone marrow cells (BMCs), harvested by the perfusion or aspiration methods. Nucleus pulposus cells were isolated from tail intervertebral discs of F344/slc rats, and BMCs were obtained from femora. Proteoglycan synthesis, DNA synthesis, and aggrecan mRNA expression were measured. The level of transforming growth factor-beta in supernatants from the culture system was also measured. Cell number, aggrecan mRNA expression, and uptake of [(35)S]-sulfate and [(3)H]-thymidine by nucleus pulposus cells cocultured with fresh whole BMCs all increased significantly compared with nucleus pulposus cells cocultured with MSCs. TGF-beta secreted by nucleus pulposus cells cocultured with fresh whole BMCs also significantly increased when compared with cocultures with MSCs. The perfusion method was superior to the aspiration method for preventing contamination of BMCs with peripheral red blood cells and lymphocytes, which may cause an autoimmune response in the disc. In conclusion, we suggest that fresh whole BMCs harvested by the perfusion method are more effective for increasing the proliferative and matrix synthesis capacity of nucleus pulposus cells.

Microsurgical bilateral decompression via a unilateral approach for lumbar spinal canal stenosis including degenerative spondylolisthesis.

OBJECT: Surgical outcome and radiographic changes after microsurgical bilateral decompression via a unilateral approach (MBDU) for lumbar spinal canal stenosis during midterm follow-up periods (> 2 years) have not been reported. The authors retrospectively investigated surgical outcomes after MBDU in patients with lumbar degenerative spondylolisthesis with stenosis in comparison with patients with degenerative stenosis during a minimum follow-up period of 2 years. Radiographic changes at the affected intervertebral level were analyzed during that follow-up period. METHODS: Forty-eight patients (23 in the spondylolisthesis group, 25 in the degenerative stenosis group) were included in the study. The average follow-up period was 46 months (range 24-71 months). Surgical outcome was evaluated using the Neurogenic Claudication Outcome Score (NCOS) and the Oswestry Disability Index (ODI). Additionally, the back pain score within the NCOS was also compared. There were no statistically significant differences between the spondylolisthesis group and the degenerative stenosis group with regard to sex, age, follow-up period, operating time, blood loss, surgical sites, approach side, preoperative NCOS, preoperative back pain score, and preoperative ODI. Comparisons were also made between groups using 2 satisfaction measurements at the last follow-up visit. Radiographically, intervertebral angles of 80 sites and slip percentages of 24 sites were measured preoperatively and at the last follow-up. RESULTS: No patient in either group had additional surgery in the lumbar spine, including fusion procedures. The NCOS, back pain score, and ODI had significantly improved at the last follow-up in both groups. There were no significant differences between the 2 groups in these 3 parameters and the 2 satisfaction measurements at the last follow-up, although those for the spondylolisthesis group indicated a somewhat worse outcome. Intervertebral angles, dynamic intervertebral angles, and dynamic slip percentage did not significantly change after surgery, whereas only slip percentage significantly increased postoperatively (p = 0.0319). CONCLUSIONS: A satisfactory outcome of MBDU persisted for a period longer than 2 years for patients with degenerative spondylolisthesis with stenosis as well as for those with degenerative stenosis. Radiographically in both groups this less invasive procedure was not likely to result in postoperative dynamic instability at the affected level, although the slippage progressed in the spondylolisthesis group.

Pigmented villonodular synovitis originating from the lumbar facet joint: a case report.

The authors successfully treated a rare case of pigmented villonodular synovitis (PVNS) that originated from the lumbar facet joint (L4-5). A 43-year-old man presented with a complaint of left severe sciatica causing difficulty in walking. Magnetic resonance imaging (MRI) demonstrated an extradural mass on the left side at L4 and the mass compressed the dural tube and was continuous with the left L4-5 facet joint. A computed tomography myelogram revealed an extradural defect of contrast medium at the L4 level and an erosion of the L4 lamina. A total synovectomy with unilateral osteoplastic laminectomy was performed. The histological findings were a diagnosis of PVNS. The patient's symptoms resolved completely and the MRI at postoperative 3 years demonstrated no recurrence of PVNS. It is important to totally remove the synovium, which is the origin of PVNS in order to prevent the recurrence. We think that our procedure is reasonable and adequate for lumbar PVNS.

Microsurgical posterior foraminotomy with laminoplasty for cervical spondylotic radiculomyelopathy including cervical spondylotic amyotrophy.

OBJECT: The authors retrospectively investigated the surgical outcomes and radiographically documented changes after microsurgical posterior foraminotomy with en bloc laminoplasty in patients with cervical spondylotic radiculomyelopathy (CSRM), including cervical spondylotic amyotrophy (CSA), during a period greater than 2 years. METHODS: Thirty-four consecutive patients (24 men and 10 women) were included in this study. Twenty patients had preoperative radicular pain, and CSA was diagnosed in 14 patients. The mean age at the time of surgery was 61 years (range 43-77 years). The follow-up period ranged from 2 to 6.5 years (mean 3.4 years). Foraminotomy was performed at 49 sites. Neurological improvement was evaluated using the Japanese Orthopaedic Association (JOA) scoring system; radicular pain and deltoid muscle strength were also evaluated clinically. Cervical lordosis, flexion-extension angles, range of motion (ROM), and the angulation and the extent of vertebral slippage at the affected nerve root levels were measured preoperatively and at last follow-up examination. The mean rate of JOA score improvement was 67.2% (range 22.2-100%). In all 20 patients, preoperative radicular pain completely resolved after surgery. In all 14 patients with CSA, deltoid muscle strength improved; in approximately 80% of these patients, there was either no muscle weakness or only slight weakness. The flexion angles and ROM significantly decreased at the time of the last follow-up examination (p = 0.0402 and 0.0196, respectively). No other items changed significantly. CONCLUSIONS: The aforementioned surgical procedure was safely completed and the surgical outcomes were satisfactory for CSRM including CSA. The instability (the angulation and the vertebral slippage) did not significantly change after surgery. This procedure yielded outstanding results and should be considered an option for cervical laminoplasty in the future.

Two-level disc herniation in the cervical and thoracic spine presenting with spastic paresis in the lower extremities without clinical symptoms or signs in the upper extremities.

BACKGROUND CONTEXT: There is no report in the literature of two-level disc herniation in the cervical and thoracic spine presenting with spastic paresis/paralysis exclusively in the bilateral lower extremities. PURPOSE: To identify the clinical characteristics of specific myelopathy resulting from C6-C7 disc herniation through a case with spastic paresis in the lower extremities without upper extremities symptoms due to separate disc herniation in the cervical and thoracic spine, which was surgically removed in two stages. STUDY DESIGN/SETTING: A case report. METHODS: A 48-year-old man developed a gait disturbance as well as weakness and numbness in the lower extremities. Thoracic magnetic resonance imaging (MRI) showed a T11-T12 disc herniation, which was removed under the surgical microscope through a minimally invasive posterior approach. He improved, but 2 months after surgery developed recurrent numbness and spasticity. On this occasion, no evidence of recurrence of the thoracic disc herniation could be identified, but cervical MRI demonstrated a compressed spinal cord at the C6-C7 level. The patient had no neurological findings in the upper extremities. The herniated disc at C6-C7 was removed under the surgical microscope with laminoplasty. RESULTS: The symptoms gradually improved after surgery. At the present time, 2 years and 9 months after the initial operation, the patient had a stable gait and was able to work. CONCLUSIONS: Our experience suggests that in the diagnosis of patients with spastic paresis and sensory disturbances in the lower extremities, spinal cord compression should be explored by imaging studies not only in the thoracic spine but also in the cervical spine, especially at the C6-C7 level, even if the symptoms and abnormal neurological findings are absent in the upper extremities.

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.

Microsurgical posterior herniotomy with en bloc laminoplasty: alternative method for treating cervical disc herniation.

OBJECTIVE: At the present time, the anterior cervical discectomy and fusion procedure is widely accepted for treating cervical disc herniation. Recently, however, several authors have reported new disease due to degeneration of an adjacent segment. On the other hand, posterior discectomy, which can preserve mobility at the affected disc level, has been considered risky and technically difficult, especially for central or paracentral disc herniation. We are performing a new surgical technique, microsurgical posterior herniotomy with en bloc laminoplasty, for patients with myelopathy and radiculomyelopathy caused by cervical disc herniation. METHODS: Here, the surgical outcomes and radiographic changes were retrospectively investigated. Thirty patients (13 patients with myelopathy, 13 patients with radiculomyelopathy, and 4 patients with C5 dissociated motor loss) who underwent this procedure were reviewed. The average age was 50 years (range 31-70 years), and the average follow-up period was 28 months (range 12-76 months). Neurologic improvements were evaluated using the Japanese Orthopaedic Association (JOA) Scoring System as well as radicular pain and deltoid muscle power. Postoperative axial symptoms were scored, and radiographic changes were noted. RESULTS: The mean JOA score improvement was 74.2% (range 27.3-100%). In all 13 patients, preoperative radicular pain completely resolved after surgery. Deltoid power (in cases of C5 dissociated motor loss) markedly increased postoperatively. Cervical lordosis significantly increased at the time of the last follow-up (P = 0.01). The postoperative axial symptom score significantly correlated with the numbers of opened laminae (P = 0.03). CONCLUSIONS: This technique was safe and effective. Radiographically, the range of motion in the cervical spine and at the affected disc levels was preserved. In the future, this surgical procedure can become an alternative method for cervical disc herniation treatment.

Preventing C5 palsy after laminoplasty.

STUDY DESIGN: The incidences of postoperative C5 palsy between a group treated by a standardized diagnostic and surgical treatment and a control group treated by a different cervical laminoplastic technique were prospectively compared. OBJECTIVE: To investigate the cause, risk factors, and prevention of C5 palsy after laminoplasty for cervical myelopathy. SUMMARY OF BACKGROUND DATA: No one factor could predict postoperative C5 palsy, although postoperative C5 palsy is a clinically significant complication of cervical laminoplasty. METHODS: One hundred eleven patients who underwent laminoplasty for cervical myelopathy were studied. Seventy-four patients who consulted two spinal surgeons (two of the authors) were placed into Group A. Thirty-seven patients who consulted the other two spinal surgeons (the other two authors) were placed into Group B. There were no statistical differences between the two groups for age at operation, gender, spinal disorders, preoperative neurologic severity, and length of the follow-up period. All patients in Group A underwent preoperative electromyographic testing. Patients with no electromyographic abnormalities underwent a standard midsagittal laminoplasty. Those with preoperative electromyographic abnormalities, reflecting a subclinical radiculopathy, underwent a modified en bloc laminoplasty with microcervical foraminotomy done at each level of the EMG abnormality. All Group B patients underwent midsagittal laminoplasty without preoperative electromyographic testing. Microcervical foraminotomy was performed for C5 root in 11 patients (14.9%) of Group A. RESULTS: No patients in Group A and three patients (8.1%) in Group B experienced postoperative C5 palsy. This difference was statistically significant (P = 0.035, Fisher's exact method). CONCLUSIONS: Electromyography is a sensitive predictor of postoperative C5 palsy after laminoplasty. This complication may be avoided by performing selective foraminotomy in addition to posterior central canal decompression. Preexisting subclinical C5 root compression is a cause of C5 palsy after posterior cervical decompression for myelopathy.