Presence of residual material following mini-hemilaminectomy in dogs with thoracolumbar intervertebral disc extrusion

Presence of residual material following mini-hemilaminectomy in dogs (n = 9) with spontaneous thoracolumbar intervertebral disc extrusion was prospectively investigated. Volume of extruded disc material within the vertebral canal and the proportion of residual material were determined using pre- and post-operative magnetic resonance imaging. The degree of spinal cord compression, proportion of extradural material considered hemorrhage, and invasion of the articular facets were also determined. Residual material was identified in 44% of the mini-hemilaminectomies. The median percentage of residual material calculated was 7.7% of the preoperative volume. No observed effect of surgical side or site, proportion of extradural material considered hemorrhage, patient weight, and duration of clinical signs was detected.

Paraplegia by spinal cord compression as the initial manifestation of Hodgkin's disease: a case report

The 90% of Hodgkin's disease (HD) cases are originated by lymphnodes whereas 10% by extranodal regions as epidural space. Neurologic complications of HD can be classified as directly resulting from the disease or indirectly originated from the disease or from its treatment. Patients very rarely present with spinal cord compression (SCC)  due to epidural HD. Few cases of HD with such presentation have been reported in the literature. Primary spinal extradural HD with no further organ involvement is extremely rare. We report a case of a child with SCC as initial and unique presentation of HD.

Comparison of the access window created by hemilaminectomy and mini-hemilaminectomy in the thoracolumbar vertebral canal using computed tomography

Hemilaminectomy and mini-hemilaminectomy were performed on opposite sides of the spine at T11-T12, T13-L1, and L2-L3 in 11 canine cadavers in order to report differences in the access provided to the thoracolumbar vertebral canal. Measurements of the vertebral canal height, defect height, and dorsal and ventral remnants of the vertebral arch were obtained after computed tomography. A median of 7% to 20% of the vertebral canal height was not removed dorsally after mini-hemilaminectomy compared to 1% to 2% in hemilaminectomy. Thirteen to 25% of the vertebral canal height was left ventrally in mini-hemilaminectomy and 11% to 27% in hemilaminectomy. Potential for a restricted exposure of thoracolumbar lesions should be considered if lesions are located in the ventral 11% to 27% vertebral canal height when performing either procedure or in the dorsal 7% to 20% of the canal height when performing a mini-hemilaminectomy.

Laminoplasty and laminectomy hybrid decompression for the treatment of cervical spondylotic myelopathy with hypertrophic ligamentum flavum: a retrospective study

OBJECTIVE

To report the outcomes of a posterior hybrid decompression protocol for the treatment of cervical spondylotic myelopathy (CSM) associated with hypertrophic ligamentum flavum (HLF).

BACKGROUND

Laminoplasty is widely used in patients with CSM; however, for CSM patients with HLF, traditional laminoplasty does not include resection of a pathological ligamentum flavum.

METHODS

This study retrospectively reviewed 116 CSM patients with HLF who underwent hybrid decompression with a minimum of 12 months of follow-up. The procedure consisted of reconstruction of the C4 and C6 laminae using CENTERPIECE plates with spinous process autografts, and resection of the C3, C5, and C7 laminae. Surgical outcomes were assessed using Japanese Orthopedic Association (JOA) score, recovery rate, cervical lordotic angle, cervical range of motion, spinal canal sagittal diameter, bone healing rates on both the hinge and open sides, dural sac expansion at the level of maximum compression, drift-back distance of the spinal cord, and postoperative neck pain assessed by visual analog scale.

RESULTS

No hardware failure or restenosis was noted. Postoperative JOA score improved significantly, with a mean recovery rate of 65.3 ± 15.5%. Mean cervical lordotic angle had decreased 4.9 degrees by 1 year after surgery (P<0.05). Preservation of cervical range of motion was satisfactory postoperatively. Bone healing rates 6 months after surgery were 100% on the hinge side and 92.2% on the open side. Satisfactory decompression was demonstrated by a significantly increased sagittal canal diameter and cross-sectional area of the dural sac together with a significant drift-back distance of the spinal cord. The dural sac was also adequately expanded at the time of the final follow-up visit.

CONCLUSION

Hybrid laminectomy and autograft laminoplasty decompression using Centerpiece plates may facilitate bone healing and produce a comparatively satisfactory prognosis for CSM patients with HLF.

Surgical management of cervical spondylotic myelopathy - indications for anterior, posterior or combined procedures for decompression and stabilisation

BACKGROUND

The authors describe their experience with the choice of anterior, posterior and combined approaches for the surgical treatment of spondylotic myelopathy.

METHODS

Description of surgical anatomy, surgical technique, indications, limitations, complications, specific perioperative considerations and specific information to give to the patient about surgery and potential risks and a summary of 10 key points is given.

CONCLUSIONS

If the disease extends behind the posterior vertebral body and if reestablishing spinal sagittal and coronal balance is an aim, then the anterior approach is the best choice. In cases of predominant posterior spinal cord compression and lordotic configuration the posterior approach should be preferred. Decompression of three or more levels, especially in combination with poor bone quality, requires a combined approach.

Laminoplasty versus conservative treatment for acute cervical spinal cord injury caused by ossification of the posterior longitudinal ligament after minor trauma

BACKGROUND CONTEXT

No reports to date have accurately evaluated the management for acute spinal cord injury (SCI) caused by ossification of the posterior longitudinal ligament (OPLL) after minor trauma.

PURPOSE

To assess whether outcomes of laminoplasty is better than conservative treatment.

STUDY DESIGN/SETTING

A retrospective study.

PATIENT SAMPLE

Thirty-one patients underwent surgery (L group) and 29 patients underwent conservative treatment (C group).

OUTCOME MEASURES

Disability, muscle strength, sensation, and general health status.

METHODS

Patients were managed according to routine clinical practice and the results between groups were compared. Clinical and radiographic outcomes were assessed at admission, discharge, 6 months and at the final visit. Causes for trauma, duration of hospital stay, and complication were also evaluated.

RESULTS

Causes for trauma included falling, traffic accidents and sports. Mixed and segmental types were the most frequent cause of OPLL resulting into SCI. Duration of hospital stay and complications were less in the L group. Motor and sensory scores increased in the L group at discharge (p<.05) and at 6 months (p<.05), and maintained thereafter (p>.05); scores improved significantly in the C group at 6 months (p<.05), with a slight deterioration with time (p>.05); scores in the L group were higher than in the C group at each time point after surgery (p<.05). Bodily pain and mental health in SF-36 improved at discharge in the L group (p<.05); all scores improved at 6 months in both the groups (p<.05), with better improvements in the L group (p<.05). The canal diameter increased and occupation ratio decreased in the L group (p<.05), and maintained thereafter (p<.05); a slight increase of occupation ratio was observed in the C group (p>.05). Lordotic angle and range of motion were maintained in both the groups, with no significance between groups (p>.05). High-signal intensity decreased at 6 months (p<.05) in the L group; no significant change was found in the C group during the follow-up (p>.05); Significant difference was detected between the groups at 6 months and at the final visit (p<.05).

CONCLUSIONS

Most of the OPLL patients displayed as incomplete SCI after minor trauma. Although spontaneous improvement of SCI without surgery is often observed, laminoplasty has more satisfactory outcomes, prevents late compression of cord, and reduces perioperative complications, although with no significant benefit in cervical alignment and range of motion.

[Ossification of posterior longitudinal ligament]

Ossification of posterior longitudinal ligament (OPLL) is a hyperostotic disease of the spine associated with myelopathy which is occurred by an anterior compression to the spinal cord. OPLL was first reported by Key GA in 1838, and was previously considered specific to east Asian people, especially Japanese. However, now OPLL is recognized as a subtype of diffuse idiopathic skeletal hyperosteosis, which is detected in Europe and the United States. We discuss the etiology and natural history of OPLL in this review.

Laminoplasty versus skip laminectomy for the treatment of multilevel cervical spondylotic myelopathy: a systematic review

INTRODUCTION

Laminoplasty and skip laminectomy are two specific posterior surgical approaches for multilevel cervical spondylotic myelopathy. The objective of this study was to perform a systematic review comparing the clinical results and complications of laminoplasty and skip laminectomy in the treatment of multilevel cervical spondylotic myelopathy.

MATERIALS AND METHODS

We reviewed and analyzed papers published from January 1969 to December 2012 through the Mediline, Embase, Cochrane review library, and other databases regarding the comparison between laminoplasty and skip laminectomy for multilevel cervical spondylotic myelopathy.

RESULTS

One randomized controlled trial and three non-randomized controlled trials were included in this systematic review. In three studies, the preoperative and postoperative JOA score was similar in both laminoplasty and skip laminectomy groups. In addition, for recovery rate, there was no significant difference between the groups. One study reported that, regarding SF12 scores, there was no significant difference in physical health and mental health after surgery. However, regarding cervical pain, the skip laminectomy group was better than the laminoplasty group significantly. No difference was presented in postoperative ROM and the cervical lordosis between the groups. But the ROM % (post/pre) was reported to be significantly better in the skip laminectomy group in three studies. Less blood loss and shorter operation time were observed in skip laminectomy rather than laminoplasty.

CONCLUSIONS

Based on the results above, the skip laminectomy group presented better outcomes in a variety of aspects: ROM % (post/pre), complication rate, surgical trauma, etc. However, as limited study samples were included in the paper, a claim of superiority of the two approaches could not be justified. Further studies are required on the comparison between laminoplasty and skip laminectomy.

[Surgery for degenerative spondylolisthesis of the lumbar spine using intra-articular fusion. A prospective study]

PURPOSE OF THE STUDY

The aim of the study is to present our surgical method of treating degenerative spondylolisthesis, which includes radical bilateral laminectomy to relieve compression on the spinal cord, transpedicular fixation of the segment and arthrodesis by bilateral intra-articular fusion.

MATERIAL AND METHODS

This surgery was indicated in patients with grade I or grade II of degenerative sponylolisthesis with a 4-mm or more slippage. Our prospectively studied group consisted of 46 patients (17 men, 29 women; average age, 64.2 years; range, 39-84 years). Before surgery and at 1 year after the procedure, the intensity of axial pain and that of radicular pain were each assessed using the visual Analogue Scale (VAS). Difficulty in performing daily living activities was measured by the Oswestry Disability Index (ODI). The surgical procedure included laminectomy, partial medial facetectomy, foraminotomy to relieve pressure on the spinal nerve roots and transpedicular fixation to provide stability. Using a cutter, cartilage was separated off the cortical bone and, in order to facilitate fusion, bone cavities thus produced were filed with corticospongious grafts harvested from the removed vertebral arch with Kerrison forceps. At 1-year follow-up, dynamic X-ray was used to evaluate spine alignment and, on a CT scan, the degree of intra-articular fusion was assessed. Fusion was achieved when bone density measurement showed more than 350 Hounsfield Units (HU). For the measurements, the authors used their own modified method by means of a Region of Interest (ROI) analysis. The clinical and radiographic results were statistically evaluated.

RESULTS

At 1 year after surgery, lumbar flexion-extension bending X-ray films revealed stability of the treated segments in all patients (100%). CT examination showed bone density higher than 350 HU at both joints, i.e., complete bone fusion, also in all 46 patients. The mean post-operative ODI score was significantly lower than its mean pre-operative value (23.6 vs 55.4), which was improvement by 57.4%. The differences in pre- and post-operative VAS scores were also statistically significant. The mean VAS score for low back pain decreased from 7.61 to 1.74, i.e., improvement by 77.1%, and the mean vAS score for radicular pain dropped from 6.98 to 1.24, i.e., improvement by 82.2%. Assessed by Odom's outcome criteria, the results were excellent in 26 patients and very good in 20 patients, and they were not related to age, gender or the spinal level treated. Any complications associated with the operative procedure or wound healing and requiring repeated surgical treatment were not recorded.

DISCUSSION

The surgical technique described here has advantages over other methods in reliable achieving nerve decompression, joint fusion and spinal stability at low costs and short operative time. In addition, it avoids the necessity of harvesting bone from the iliac crest.

CONCLUSIONS

At 1-year follow-up all patients showed better health conditions, with improvement in average scores for the ODI by 57%, for low back pain by 77% and for radicular and claudication pain by 82%. The technique of intra-articular fusion for treatment of degenerative spondylolisthesis resulted in solid bone fusion and spinal stability in all patients.

[Effect of penetration of mini-plate lateral mass screws into facet joint on axial symptoms in cervical laminoplasty]

OBJECTIVE

To investigate the effect of the penetration of mini-plate mass screws into facet joint on axial symptoms in cervical laminoplasty.

METHODS

A retrospective analysis was made on the clinical data of 52 patients who underwent unilateral open-door cervical expansive laminoplasty fixed with Centerpiece mini-plate between September 2009 and December 2011. There were 42 males and 10 females, with a mean age of 61.2 years (range, 34-83 years). Seventeen patients exhibited simple degeneration cervical canal stenosis, 25 patients had multilevel cervical disc protrusion, and 10 patients had ossification of posterior longitudinal ligaments. Disease duration ranged 1-120 months (median, 11 months). The Japanese Orthopedic Association (JOA) score was used to assess neurological function, and JOA recovery rates were calculated. The visual analogue score (VAS) and the neck disability index (NDI) were used to evaluate the axial pain and neck daily activities. The axial symptoms and other complications were recorded. The cervical canal diameter, cervical curvature, cervical canal cross area, and open angle were measured according to the X-ray films, CT scans, and MRI scans. The postoperative CT three dimensional (3-D) reconstruction images were used to identify whether the screws penetrated into the facet joints. All the patients were divided into 3 groups according to involved facet joints: no joint penetrating group (no penetrated facet joint), oligo-joint penetrating group (one or two penetrated facet joints), and multi-joint penetrating group (three or more penetrated facet joints).

RESULTS

Five patients suffered from C5 nerve palsy, and 2 patients had cerebrospinal fluid leakage. The follow-up time ranged 3-35 months (mean, 15.7 months). At the final follow-up, the JOA scores, NDI, cervical canal diameter, and cervical canal cross area were significantly improved when compared with preoperative ones (P < 0.05). At 1 week after operation, CT 3-D reconstruction showed that 16 patients had no penetrated facet joint, 23 patients had one or two penetrated facet joints, and 13 patients had three or more penetrated facet joints. There was no significant difference in age, gender, disease duration, operation time, intraoperative blood loss, and follow-up time among 3 groups (P > 0.05). And at the final follow-up, there was no significant difference in JOA score, VAS score, cervical curvature, cervical canal diameter, cervical canal cross area, the JOA recovery rates, and lamiae open angle among 3 groups (P > 0.05). The NDI of the multi-joint penetrated group was significantly higher than that of other 2 groups (P < 0.05). Axial pain occurred in 1 case of no penetrating group, in 4 cases of oligo-joint penetrating group, and in 5 cases of multi-joint penetrating group, showing no significant difference among 3 groups (Chi(2)=4.881, P=0.087).

CONCLUSION

The penetrations of lateral mass screws into articular surface of facet joint may contribute to the axial symptoms after cervical laminoplasty. The risk of axial symptom raises accompany with increased penetrated facet joints.

Anterior versus posterior approach for four-level cervical spondylotic myelopathy

The purpose of this study was to compare the results of 2 surgical strategies for 4-level cervical spondylotic myelopathy: a hybrid procedure using anterior cervical diskectomy and fusion (ACDF) combined with segmental corpectomy versus posterior laminectomy and fixation. Between 2002 and 2010, fifty-one patients with consecutive 4-level cervical spondylotic myelopathy were treated surgically, with 27 patients undergoing the hybrid procedure and 24 undergoing posterior laminectomy and fixation. Radiologic data were compared between the 2 groups, including cervical curvature and cervical range of motion (ROM) in the sagittal plane. Pre- and postoperative neurological status was evaluated using the Japanese Orthopaedic Association (JOA) scoring system and the Nurick grading system. Mean ROM at last follow-up was not significantly different between the 2 groups (P>.05). In the hybrid group, mean JOA score and Nurick grade improved from 9.6±1.4 and 2.74±0.45 respectively, preoperatively, to 13.9±1.3 and 0.86±0.38 respectively, postoperatively. In the fixation group, mean JOA score and Nurick grade improved from 9.4±1.2 and 2.81±0.42 respectively, preoperatively, to 13.1±1.5 and 1.32±0.36 respectively, postoperatively. The JOA scores and Nurick grades at last follow-up were significantly different between the 2 groups (P<.05). In patients with preoperative cervical kyphosis, preoperative JOA score and Nurick grade were not significantly different between the 2 groups (P>.05); however, JOA scores and Nurick grades at last follow-up showed better improvement in the hybrid group than in the fixation group (P<.01). In patients with preoperative cervical lordosis, the preoperative and last follow-up JOA score and Nurick grade were not significantly different between the 2 groups (P>.05).

Intraoperative computed tomography for cervicomedullary decompression of foramen magnum stenosis in achondroplasia: two case reports

The authors report two cases of cervicomedullary decompression of foramen magnum (FM) stenosis in children with achondroplasia using intraoperative computed tomography (iCT). A 14-month-old girl with myelopathy and retarded motor development, and a 10-year-old girl who had already undergone incomplete FM decompression was presented with myelopathy. Both patients underwent decompressive sub-occipitalcraniectomy and C1 laminectomy without duraplasty using iCT. It clearly showed the extent of FM decompression during surgery, which finally enabled sufficient decompression. After the operation, their myelopathy improved. We think that iCT can provide useful information and guidance for sufficient decompression for FM stenosis in children with achondroplasia.

Elevated preoperative blood pressure predicts the intraoperative loss of SSEP neuromonitoring signals during spinal surgery

Intraoperative neuromonitoring of somatosensory evoked potentials (SSEPs) can allow identification of evolving neurologic deficit. However, SSEP deterioration is not always associated with postoperative deficit. Transient physiologic changes, including a decrease in blood pressure (BP), can result in signal deterioration, defined as a decrease in waveform amplitude of[50 %seen without neurologic deficit. This study examines the relationship between intraoperative BP decrease and SSEP neuromonitoring to determine whether hypertensive patients are more prone to decreases in BP and if such BP declines are associated with signal loss. We conducted a retrospective review of 43 lumbar laminectomy patients at Mount Sinai. Patients were categorized based on whether they had a previous hypertension diagnosis and if they presented with a first systolic BP of greater than 140 mmHg in the admission area on the morning of surgery, two groups that were not mutually exclusive. We measured BP drop by calculating fractional mean arterial pressure (fMAP, lowest MAP/baseline MAP) and change in BP.We identified patients' SSEP tracings in which signal amplitude decreased[50 %. After dividing patients' recording times into 5-min epochs, we calculated median MAP and whether SSEPs deteriorated in each epoch. We compared the likelihood of signal loss in hypertensives to patients presenting with elevated BP, calculating the odds ratio. Elevated BP prior to surgery is associated with lower fMAP (p = 0.007) and a larger intraoperative decrease in BP (p\0.001).A diagnosis of hypertension is not associated with lower fMAP orBP drop. Lower epoch fMAPis associated with signal loss (p = 0.0026). While the presence of preoperative elevated BP predicts SSEP abnormality (p = 0.0039), a diagnosis of hypertension does not. Elevated BP, not a hypertension diagnosis, is associated with intraoperative loss of SSEP signals. This effect of elevated BP on SSEPs may be due to the larger associated intraoperative BP decline.

Evaluation of the results of operative management of lumbar spinal canal stenosis

Lumber spinal canal stenosis is an important cause of low back pain and it frequently presents with low backache with neurogenic claudication. Operative management of lumbar spinal canal stenosis by decompression surgery is an effective method. This prospective interventional (quasi experimental) study was performed in patient having history of characteristic clinical features like low backache with radicular pain, neurogenic claudication, signs of root compression, positive MRI findings attending in the department of Orthopaedic Surgery and Neurosurgery, Dhaka Medical College Hospital and NITOR. Dhaka, from July 2008 to June 2010. Thirty patients were evaluated among those 18(60%) were 50 years and above. Male to female ratio was roughly 9:1. About 87% of the patients had sensory deficit and 50% had neurogenic claudication. Majority (83.3%) of the patients at presentation had a suffering of 12 or >12 months. Diagnosis shows that 3.5% of patients had L4 lesion, 60% L5, 6.5% patients had L4 & L5 and 30% S1. Laminectomy was done in 43.3% of patients, laminectomy and disectomy in 30% and laminectomy, discectomy & foraminal decompression in 26.7% of patients. Relief of symptoms occurred in 25(83.5%) of patients. Over three-quarter (76.7%) of patients exhibited minimal disability and 23.3% moderate disability based on Oswestry Disability Index, while by MacNab criteria, most (80%) of patients was excellent, 10% good and another 10% fair. Repeated measure ANOVA statistics showed that mean Oswestry score decreased significantly from 54.5% at baseline to 22% at the end of 1 year (p<0.001).

The pitfalls of differential diagnosis of lumbar spine epidural lesions--exemplification with two particular cases and a review of the literature

BACKGROUND AND STUDY AIMS

Lumbar spinal epidural lesions could belong to a wide spectrum of pathologies. However, some cases present with rare conditions that can cause significant neurological deficit and raise serious diagnostic challenges. We present two such cases where the clinical picture and the imaging findings failed to elucidate the actual diagnosis, which came as an intraoperative and pathological surprise.

PATIENTS

The first case is that of a 78-years-old male that presented for low back pain, bilateral S1 radicular sciatica, paraparesis, and difficulty walking. The neurologic exam showed the absence of the rotulian reflexes bilaterally, and a partial sensory loss in the crural dermatomes. The MRI showed an epidural mass, contrast enhancing at the L1-L2 level, suggestive for an extraxial tumor. The second case is that of a 62-year-old woman that presented for a hyperalgic sciatica involving the right S1 root with parestesias in the corresponding dermatome. MRI showed a cystic, contrast enhancing lesion in the L5-S1 recess, mimicking a cystic neuroma. Both patients underwent surgery and histopathological exams were performed from the excised pieces.

RESULTS

In the first case the surgery resulted in complete removal of the pathological process and histopathological result returned chronic organized hematoma, concordant with the intraoperatory aspect. The evolution was good. In the second case the histopathological result came back as pulpous disk. Again the evolution was good with complete neurological recovery.

CONCLUSION

In the presence of an epidural mass with clear clinical symptomatology, rare entities like chronic epidural hematoma or posterior migrated disk material should be always considered as a differential diagnosis in patients with suspicion of extradural chronic compressions. In these cases, only the intraoperatory and histopathological exams can provide a clear diagnosis.

[Discussion of surgical indications for posterior expansive open-door laminoplasty extended to C1 level]

OBJECTIVE

To determine the surgical indications for posterior expansive open-door laminoplasty (EOLP) extended to the C1 level.

METHODS

Seventeen patients undergoing C3-7 or C2-7 open-door laminoplasty were included as the case group between September 2005 and January 2010, whose spinal cord injury symptoms were not alleviated or aggravated again because of the cervical stenosis at C-4 level, and the causes of the surgery itself were eliminated, all of these patients underwent reoperation with decompress upward to C1 level. Fifteen patients with cervical stenosis who underwent C2-7 laminoplasty and C1 laminectomy were selected as the control group. There was no significant difference in gender, age, and disease duration between 2 groups (P > 0.05). The pre- and post-operative cervical curvature and spinal cord compression were evaluated according to the patients' imaging data; the pre- and post-operative neurological recovery situation was evaluated by Japanese Orthopaedic Association (JOA) 17 score and spinal cord function Frankel grade; the neurological recovery rate (according to Hirabayashi et al. method) was used to assess the postoperative neurological recovery situation.

RESULTS

In the case group, 8 patients underwent primary C37 laminoplasty. In 3 of these patients, there was a cervical stenosis at C1, 2 level, and discontinuous cerebrospinal fluid around the spinal cord was observed; 5 of them with a compression mass which diameter was exceed 7.0 mm in the C2-4 segments. The remaining 9 patients in the case group underwent primary C2-7 laminoplasty, and the diameter of the compression mass was exceed 7.0 mm in the C2-4 segments. In all 17 patients of the case group, reoperation was performed with the decompression range extended to the C1 level, and the follow-up time was 35-61 months with an average of 45.6 months. Cervical curvature: there were 11 cases of cervical lordosis, 4 cases of straight spine, and 2 cases of cervical kyphosis before operation; but after operation, 2 cases of cervical lordosis became straight spine and 1 straight case became kyphosis. The postoperative neurological improvement was excellent in 8 cases, good in 7, and fair in 2. In the control group, all the patients had a compression mass which anteroposterior diameter was exceed 7.0 mm in the C2-4 segments before operation. The follow-up time was 30-58 months with an average of 38.7 months. Cervical curvature: there were 13 cases of cervical lordosis and 2 cases of straight spine before operation; but after operation, 1 case of cervical lordosis became straight spine. The postoperative neurological improvement was excellent in 8 cases, good in 6, and fair in 1. No significant difference was found in the JOA score at pre- and post-operation between 2 groups (P > 0.05); however, there were significant differences (P < 0.05) in the JOA score between at last follow-up and at preoperation.

CONCLUSION

The initially surgical indications which can be used as a reference for EOLP extended to C1 are as follows: (1) Upper cervical (C1, 2) spinal stenosis: C1 posterior arch above the lower edge part of cerebrospinal fluid around the spinal cord signal is not continuous, and the anteroposterior diameter of the spinal canal actual is less than 8.0 mm as judgment standard. (2) There is a huge compression at the lower edge of C2-4 vertebrae, and the most prominent part of the diameter is exceed 7.0 mm, which can not be removed through the anterior cervical surgery, or the operation is high-risk.

Split laminotomy and complementary spacer insertion for opening and enlargement of the thoracic spinal canal at infiltrative intramedullary tumor removal

OBJECTIVE

The author main objective was to improve the previously developed technique of split laminotomy and moderate enlargement of the spinal canal with preservation of the majority of posterior structures, and to avoid the complications of the classic autologous bone grafting procedure.

METHODS

A multilevel spinous process splitting and distracting laminotomy technique with complementary spacer insertion between the laminar parts was developed. We used Poly-Ether-Ether-Ketone (PEEK) cages. This improved method was used in five patients to remove malignant intramedullary tumors at the thoracic level.

RESULTS

Adequate surgery of the tumors located intramedullary, and permanent decompression of the spinal canal was achieved in all patients using our new modified procedure. The results have been postoperatively confirmed with MRI and CT. The affected spine was the thoracic in all cases. The numbers of split laminae were three to five. Histological results were as follows: four intramedullary astrocytomas, one ependymoma. The ependymoma was completely, while the astrocytomas were only subtotally removed. In all cases heterologous grafts were inserted between the sides of the distracted laminas, to achieve the enlargement of the spinal canal. The mean duration of the whole surgical procedure was 118 minutes (range 91 to 145 minutes). The average follow-up was 11.2 months, with the range from five to 16 months. Upon postoperative neurological follow-up, no complications were revealed related to the newly developed procedure. The postoperative followup CT scans demonstrated bony healing, with a cage between the osteotomized faces. No compression or dislocation of the spacer was seen. Instability was not detected in any of the patients by flexion or extension lateral radiographs.

CONCLUSION

This modification of the split laminotomy and heterologous grafting method fulfills the requirements of other laminotomy techniques. The split laminotomy is suitable for removing intramedullary tumors, and the posterior stabilizing structures of the spine, as the vertebral laminae and the longitudinal musculature are completely prevented. Due to use of allograft the complications of the classic hip bone grafting procedures are avoided. The spacers, inserted between the osteotomized faces, provided permanent decompression of the spinal canal, and bony healing--throughout the spacer--of the splitted vertebral laminae, without iliac graft complications.

Surgical outcomes in spinal cord subependymomas: an institutional experience

Spinal cord subependymomas are very rare. Most studies on spinal cord subependymomas have been case reports with literature reviews. This study presented a surgical series of 13 patients with histologically proven spinal cord subependymomas. Their clinical data, radiological findings, operative records, and follow-up outcomes were reviewed. There were 5 male and 8 female patients with a mean age of 39.5 years. The mean follow-up period was 67.8 months. Four tumors were located in the cervical spine, 5 in the cervicothoracic spine, and 4 in the thoracic spine. Gross total resection (GTR) of the tumor with a well-demarcated dissection plane was achieved in 9 cases, and subtotal resection was achieved in 4 cases. The symptoms present before the surgery were improved in 11 cases at last follow-up and the current status of 2 patients had no change compared to the preoperative presentation at last follow-up. The postoperative follow-up magnetic resonance imaging showed no recurrence in the 9 GTR cases during the mean follow-up period of 70.3 months. No recurrence/regrowth of the residual tumors was observed in the 4 STR cases during the mean follow-up period of 62.0 months. Spinal cord subependymomas are amenable to surgical resection. It is possible to achieve GTR of intramedullary subependymomas that have a well-demarcated dissection plane. When GTR cannot be achieved, STR of the lesion for decompression is advised, and follow-up imaging is needed. A good clinical outcome after GTR or STR can be expected.

[Spondylarthrosis of the cervical spine. Therapy]

Chronic neck pain is often associated with spondylarthrosis, whereby segments C4/C5 (C: cervical) are most frequently affected. Spondylarthrosis can be the sole complaint, but it is associated with a degenerative cascade of the spine. The umbrella term for neck pain is the so-called cervical syndrome, which can be differentiated into segmental dysfunction and/or morphological changes of the intervertebral discs and small joints of the vertebral column. Conservative therapy modalities include physical therapy, subcutaneous application of local anesthetics, muscle, nerve and facet joint injections in addition to adequate analgesic and muscle relaxant therapy. If surgery is required, various techniques via dorsal and ventral approaches, depending on the clinic and morphologic changes, can be applied.

Improvement in low back pain following spinal decompression: observational study of 119 patients

STUDY DESIGN

Prospective clinical observational study of low back pain (LBP) in patients undergoing laminectomy or laminotomy surgery for lumbar spinal stenosis (LSS).

OBJECTIVES

To quantify any change in LBP following laminectomy or laminotomy spinal decompression surgery.

PATIENTS AND METHODS

119 patients with LSS completed Oswestry Disability Index questionnaire (ODI) and Visual Analogue Scale for back and leg pain, preoperatively, 6 weeks and 1 year postoperatively.

RESULTS

There was significant (p < 0.0001) reduction in mean LBP from a baseline of 5.14/10 to 3.03/10 at 6 weeks. Similar results were seen at 1 year where mean LBP score was 3.07/10. There was a significant (p < 0.0001) reduction in the mean ODI at 6 weeks and 1 year postoperatively. Mean ODI fell from 44.82 to 25.13 at 6 weeks and 28.39 at 1 year.

CONCLUSION

The aim of surgery in patients with LSS is to improve the resulting symptoms that include radicular leg pain and claudication. This observational study reports statistically significant improvement of LBP after LSS surgery. This provides frequency distribution data, which can be used to inform prospective patients of the expected outcomes of such surgery.

Is cervical lordosis relevant in laminoplasty?

BACKGROUND CONTEXT

Laminoplasty aims to decompress the spinal cord and stabilize the cervical spine in patients with multilevel cervical lesions. Not every patient with cervical compressive myelopathy is a good candidate for laminoplasty. Most studies recommend that neutral or kyphotic alignments are contraindications for laminoplasty. However, cervical sagittal alignment does not have a strong and consistent effect on the clinical outcomes of laminoplasty. Moreover, many reports on the effect of cervical sagittal alignment did not designate the ideal definition of alignment and used different definitions of lordosis.

PURPOSE

To identify the effect of preoperative cervical alignment according to two different definitions after midline splitting double-door laminoplasty.

STUDY DESIGN

Retrospective cohort study.

PATIENT SAMPLE

From August 2008 to September 2010, 58 patients were diagnosed with cervical myelopathy and treated with midline splitting double-door laminoplasty.

OUTCOME MEASURES

The clinical results were assessed with the modified Japanese Orthopedic Association (JOA) score, neck disability index (NDI), and visual analog scale (VAS) and were compared to analyze the rate of change between preoperative and postoperative values. Postoperative radiological results at the final follow-up examinations were compared between groups to obtain the change in range of motion and sagittal alignment.

METHOD

The effect of cervical alignment on JOA, NDI, and VAS scales and also on change of alignment and change of range of motion (ROM) at the final follow-up examinations was analyzed statistically between two groups according to two different definitions such as Toyama classification and Cobb angle.

RESULTS

No difference was found between the two groups according to Toyama classification in terms of the postoperative improvement rate of the modified JOA score (p=.086), decreasing rate of the VAS (p=.940) or NDI (p=.211), postoperatively. Additionally, no difference was found for the decreasing rate of ROM (p=.427) or sagittal alignment (p=.864) based on the radiological evaluation results. Also, there was no difference between two groups according to Cobb angle in terms of the modified JOA score (p=.743), VAS (p=.548), or NDI (p=.32), postoperatively. Additionally, no difference was found for the ROM (p=1.000) or sagittal alignment (p=.440) based on the radiological evaluation results.

CONCLUSIONS

Despite nonlordosis cervical sagittal alignment, double-door laminoplasty would be effective for patients with cervical myelopathy because of cervical spondylotic myelopathy or ossification of the posterior longitudinal ligament. Furthermore, sagittal alignment is not the absolute and sole factor that surgeons should consider when determining the optimal treatment strategy.

Secondary spinal cord hypoperfusion of circumscribed areas after injury in rats

OBJECTIVES

The evaluation of the spatial spread of ischemia following spinal cord injury (SCI) is important for planning therapeutic strategies for secondary injury. The purpose of this study was to investigate in detail the change in regional spinal cord blood flow (rSCBF) after SCI.

METHODS

Thirty-four male Wistar rats were used, for which laminectomies of the T11-13 vertebrae were performed. SCI was produced by a directed impact through a laminectomy site at the level of the Th12 using a pneumatic impact device. We measured the sequential and spatial changes of rSCBF using a laser Doppler scanning technique before and after SCI in rats not only at the injured myelomere but also at the circumferent myelomeres. SCBF mapping was carried out before and after SCI on each site.

RESULTS

After SCI, the rSCBF value gradually decreased for each site for the SCI group (n=26), while it globally decreased at the epicenter. Moreover, a decrease in SCBF was observed at the caudal and rostral sites. The mean value of the %SCBF 120 minutes after SCI for each site was 63.6+/-2.3% (Th11), 74.4+/-4.5% (Th12), 75.8+/-3.2% (Th13), and was significantly lower for the rostral site compared with the caudal site (p<0.05, one-way analysis of variance).

DISCUSSION

This study found that SCBF is significantly decreased not only at the injured myelomere but also at the circumferent myelomeres. Circumferentially extending ischemia after SCI is related to secondary injury after SCI. The improvement in SCBF after SCI, therefore, can be attributed to the treatment of SCI.

Surgical management of symptomatic Chiari II malformation in infants and children

PURPOSE

Variation exists in the surgical methods employed for decompression of Chiari II malformation (CIIM), yet an evaluation of these techniques has not been performed. The purpose of this study was to assess the efficacy of bony decompression (cervical laminectomy alone versus suboccipital craniectomy with laminectomy) with or without dural augmentation for the treatment of symptomatic CIIM.

METHODS

Clinical records of children 0-18 years of age who underwent surgical repair of myelomeningocele or CIIM decompression at St. Louis Children's Hospital (SLCH) from 1990-2011 were reviewed. Signs/symptoms prompting decompression, surgical technique, operative parameters, and clinical outcomes were recorded for analysis.

RESULTS

Thirty-three subjects were treated at SLCH for CIIM decompression. Twenty-six subjects underwent bony decompression only (21 cervical laminectomy alone, 5 suboccipital craniectomy + cervical laminectomy) while seven underwent bony decompression with upfront dural augmentation (three cervical laminectomy alone, four suboccipital craniectomy + cervical laminectomy). Median follow up was 5.0 years (range, 3 months-19 years). Symptomatic improvement was noted in 20/33 subjects (60.6%). Sixty-two (61.5%) percent of children who underwent bony decompression had symptomatic improvement, compared with 57.1% of those with upfront dural augmentation (p = 0.37). Estimated blood loss, operative time, and length of perioperative hospital stay appeared lower in the bony decompression group but were not statistically different in this limited cohort.

CONCLUSIONS

The results from this series suggest that bony CIIM decompression via tailored cervical laminectomies alone, without suboccipital craniectomy or upfront dural augmentation, is a reasonable initial management approach for decompression of symptomatic CIIM.

Primary extraosseous intradural spinal Ewing's sarcoma: report of two cases

Two cases of primary extraosseous intradural spinal Ewing's sarcoma are reported with a review of the current literature. This rare neoplasm shares features with cerebral primitive neuroectodermal tumors, complicating a correct diagnosis. Gross total resection seems to be the main treatment, although adjuvant therapies could improve the prognosis. In case 1, a 56-year-old man presented with cauda equina syndrome. MRI showed an intradural tumor from L4 to S2. An emergency laminectomy was performed with gross total resection of a hemorrhagic tumor, followed by adjuvant treatment. In the second case, a 25-year-old female developed leg and lumbar pain. MRI study identified a homogeneously enhancing intradural mass at the L2-L3 level. A laminoplasty was performed, followed by tumor resection; no adjuvant treatment was administered afterwards. Immunohistochemical workup confirmed the diagnosis of Ewing's sarcoma in both cases.

A retrospective evaluation of the clinical success of transforaminal endoscopic discectomy with foraminotomy in geriatric patients

BACKGROUND

The elderly population is growing in the United States. As the oldest old are projected to be the fastest growing part of the elderly population, we must consider how to best treat their degenerative spine conditions when non-operative treatment fails.

OBJECTIVES

Transforaminal endoscopic discectomy and foraminotomy is an ultra-minimally invasive outpatient surgical option that does not require general anesthesia and is available to geriatric. The purpose of this study was to assess the benefit of transforaminal endoscopic discectomy and foraminotomy in geriatric patients with single level and multi-level lumbar disc herniations and lumbar radiculopathy.

STUDY DESIGN

Retrospective study

SETTING

Outpatient surgery center.

METHODS

After Institutional Review Board Approval, charts from 50 consecutive patients aged 75 and older with complaints of lower back and radicular pain who underwent one or more endoscopic procedures between 2007 and 2011 were reviewed.

RESULTS

The average pain relief 6 months postoperatively was reported to be 71.8%, good results as defined by MacNab. The average pre-operative VAS score was 9.04, indicated in our questionnaire as severe and constant pain. The average 6 month post-operative VAS score was 2.63, indicated in our questionnaire as mild and intermittent pain.

LIMITATIONS

This is a retrospective study and only offers 6 month follow-up data for geriatric patients undergoing endoscopic spine surgery.

CONCLUSIONS

Endoscopic discectomy is a safe and effective alternative to open back surgery. The 6-month follow-up data presented here appears to indicate that an ultra-minimally invasive approach to the geriatric spine that has a low complication rate, avoids general anesthesia, and is outpatient might be worth studying in a prospective, longer term way. IRB approval: Meridian Health: IRB Study # 201206071J.

[Combined cervical posterior-anterior operation for treatment of cervical spinal canal stenosis with reverse arch]

OBJECTIVE

To evaluate the effectiveness of combined posterior decompression with laminoplasty and anterior decompression with fusion for the treatment of cervical spinal canal stenosis with reverse arch.

METHODS

Between May 2009 and February 2012, 13 cases of cervical spinal canal stenosis with reverse arch underwent posterior decompression with laminoplasty surgery in prone position and then anterior decompression with fusion surgery in supine position. There were 7 males and 6 females with an average age of 43.5 years (range, 38-62 years) and an average disease duration of 25 months (range, 18-60 months). All the patients had neck axial symptoms and spinal cord compressed symptoms, and lateral computer radiology (CR) of the neck showed reverse arch of cervical vertebrae. Segments of intervertebral disc protrusion included C3-6 in 4 cases, C4-7 in 4 cases, and C3-7 in 5 cases. After operation, anteroposterior and lateral CR was used to observe the cervical curvature change and fixation loosening, MRI to observe the change of the compression on spinal cord, visual analogue scale (VAS) score to evaluate the improvement of axial symptom, and Japanese Orthopaedic Association (JOA) score to assess the nerve function improvement.

RESULTS

All incisions healed by first intention. All patients were followed up 9-32 months (mean, 15.4 months). Internal fixator had good position without loosening or breaking and the compression on spinal cord improved significantly after operation. All the patients obtained bony fusion at 6 months after operation. The axial symptoms and the nerve function at last follow-up were improved. VAS score at last follow-up (3.25 +/- 1.54) was significantly lower than that at preoperation (6.55 +/- 1.52) (P < 0.05); JOA score at last follow-up (10.45 +/- 4.23) was significantly higher than that at preoperation (7.05 +/- 1.32) (P < 0.05); and cervical curvature value at last follow-up [(6.53 + 3.12) mm] was significantly higher than that at preoperation [(3.22 +/- 5.15) mm] (P < 0.05).

CONCLUSION

Combined posterior decompression with laminoplasty and anterior decompression with fusion for the treatment of cervical spinal canal stenosis with reverse arch is a safe and effective surgical method.

Laminarthrectomy as a surgical approach for decompressing the spinal canal: assessment of preoperative versus postoperative dural sac cross-sectional areal (DSCSA)

INTRODUCTION

Surgery for lumbar spinal stenosis (LSS) is today the most frequently performed procedure in the adult lumbar spine. Long-term benefit of surgery for LSS is well documented both in randomized and in non-randomized trials. In this paper, we present the results from laminarthrectomy as an alternative surgical approach, which have theoretical advantages over other approaches. In this study, we wanted to study the clinical and radiological results of laminarthrectomy. Dural sac cross-sectional areal (DSCSA) is an objective method to quantify the degree of central stenosis in the spinal canal, and was used to measure whether we were able to achieve an adequate decompression of the spinal canal with laminarthrectomy as a surgical approach.

MATERIALS AND METHODS

All patients operated on with this approach consecutively in the period 1 January 2008 to 31 March 2009 were included in the study. All perioperative complications were noted. Clinical results were measured by means of a questionnaire. The patients that agreed to attend the study had an MRI taken of the operated level. DSCSA before and after surgery of the actual level were measured by three observers. We then performed a correlation test between increase of area and clinical results. We also tested for inter- and intra-observer reability.

RESULTS

Fifty-six laminarthrectomy were performed. There were 17% complications, none of them were life-threatening or disabling. 46 patients attended the study and answered the questionnaire. Thirty-four patients (83%) reported clinical improvement, whereas six (13%) patients reported no improvement, and two (4%) patients reported that they were worse. Mean ODI was 23.0. Mean EQ-5D was 0.77. Mean VAS-score for back-pain was 3.1 and mean VAS-score for leg-pain was 2.8. Mean DSCSA were measured to 80 mm(2) before surgery and 161 mm(2) after surgery. That gave an increase of DSCSA of 81 mm(2) (101%). We found a significant positive correlation between increase of area and clinical results. We also found consistent inter- and intra-observer reability.

DISCUSSION

In this study, the clinical results of laminarthrectomy were good, and comparable with other reports for LSS. The rates of complications are also comparable with other reports in spinal surgery. A significant increase in the spinal canal diameter was achieved. Within the limitations a retrospective study gives, we conclude that laminarthrectomy seems to be a safe and effective surgical approach for significant decompressing the adult central spinal canal, and measurement of DSCSA, before and after surgery seems to be a good way to quantify the degree of decompression.

[Centerpiece plating in the cervical single open-door laminoplasty]

OBJECTIVE

To evaluate the value of the Centerpiece plate in the cervical single open-door laminoplasty and compared its advantages with conventional suture fixation methods.

METHODS

From December 2009 to August 2011,32 patients with cervical spondylotic myelopathy were treated with operation. Of them, 15 cases underwent cervical single open-door laminoplasty and Centerpiece plate fixation (group A),there were 8 males and 7 females,aged from 51 to 65 years old with an average of 60.5 years and ranged in course of disease from 2 to 15 months; 17 cases underwent cervical single open-door laminoplasty and silk suture fixation (group B), there were 9 males and 8 females, aged from 49 to 66 years old with an average of 61.5 years and ranged in course of disease from 1 to 14 months. All the patients with unsteady gait symptom before operation and cervical MR imaging showed spinal cord compression and denaturation. According to standard of Japanese Orthopaedics Association (JOA) to evaluate the spinal nervers function before operation and at 6 months after operation;according to CT scan to determine the sagittal diameter (AP) of upper vertebral canal and cervical activity (ROM).

RESULTS

All the patients were followed up from 8 to 20 months with an average of 13 months. All the incisions healed well and no complications such as internal fixation loosening and breakage,spinal cord injury, reclose-door were found. Postoperative symptoms relieved obviously and MRI and CT showed vertebral canal volume expanded significantly. Operative time and blood loss in group A were respectively (155.0+/-12.3) min, (407.0+/-11.8) ml and in group B were respectively (148.0+/-14.4) min, (398.0+/-15.4) ml. There was no significantly differenc, between two groups (P>0.05). JOA score in group A improved from preoperative 9.1+/-2.6 to postoperative 15.5+/-1.8 and in group B improved from preoperative 9.3 +/- 2.1 to postoperative 13.1 +/- 2.5 (P<0.05). CT sagittal diameter (AP) in group A increased from preoperative (10.7+/-2.4) mm to postoperative (17.6+/-3.2) mm and in group B increased from preoperative (11.6+/-1.7) mm to postoperative (15.9+/-2.0) mm (P<0.05). Cervical activity (ROM) in group A be- fore and after operation were respectively (51.0+/-2.6) degrees, (45.0+/-3.5) degrees and in group B were respectively (52.0+/-1.8) and (42.0+/-2.4). There was no significantly difference before operation between two groups (P>0.05) and there was significantly difference after operation between two groups (P<0.05).

CONCLUSION

Treatment of cervical spondylotic myelopathy with posterior single open-door laminoplasty and Centerpiece plate fixation can enlarge spinal canal volume,keep original cervical activity, improve postoperative JOA score. The method has obviously advantages compared with traditional suture fixation methods.

[Analysis of postoperative complication and its preventive measure of cervical open-door expansive laminoplasty with lateral mass screw fixation]

OBJECTIVE

To explore the postoperative complication and its preventive measure of cervical open-door expansive laminoplasty with lateral mass screw fixation in treating cervical canal stenosis.

METHODS

From February 2008 to July 2011, 33 patients with cervical canal stenosis underwent cervical open-door expansive laminoplasty with lateral mass screw fixation. JOA score was used to evaluate clinical effects before and after operation. Of them, complications occurred in 6 cases, male in 2 cases and female in 4 cases. The reason of complications were analyzed.

RESULTS

All the patients were followed up from 6 months to 2 years with an average of 10.3 months. The improvement rate of JOA was 78.8% and incidence rate of complication was 18.2% (6 cases). There were 2 cases of axiality symptoms, 1 case of lateral mass screw pulled-out, 2 cases of cerebrospinal fluid leakage with wound dehiscence, 1 case of nerve root parlysis. These complications correlated with operative design, manipulation,improved degree of cervical curvature,postoperative management and cooperation of patient.

CONCLUSION

As an effective treatment, cervical open-door expansive laminoplasty with lateral mass screw fixation has lower incidence of axiality pain. Preoperative examination ,postoperative management ,meticulous surgical skill are very important to avoid complications.

Radiographic and intraoperative imaging of a hemisection of the spinal cord resulting in a pure Brown-Séquard syndrome: case report and review of the literature

Brown-Séquard plus syndrome (BSPS) or incomplete spinal cord injuries from stab injury have been widely reported. However, only four detailed cases of pure Brown-Séquard syndrome (BSS) from stab injury have been previously reported. Here we present the case of an 18-year-old man who sustained a penetrating knife stab injury to the right side of his back resulting in a pure Brown-Séquard syndrome with left lower extremity hemiplegia. Imaging revealed right-sided soft tissue and ligamentous damage traveling in a right-to-left fashion as well as left-sided T2-weighted MRI cord signal change at the level of T9. Given concern for a cerebrospinal fluid leak (CSF) leak, the patient was taken for wound exploration, irrigation, laminectomy, dural closure and lumbar drain placement. At three years follow up, the patient was almost full strength. This is the first case in the literature demonstrating radiographic and correlative intraoperative imaging of a hemisection of the spinal cord resulting in a pure Brown-Séquard syndrome.

Craniospinal dissemination of filum myxopapillary ependymoma following spinal trauma: case report and literature review

BACKGROUND

Myxopapillary ependymoma is a rare benign variant of ependymoma, occurring most commonly in the cauda equina/filum terminale of the spinal cord. It is rare in pediatric patients. Dissemination of the myxopapillary ependymoma along the neuraxis is uncommon both in adults and pediatric patients.

METHODS

We report a 16-year-old boy with dissemination of the myxopapillary ependymoma along the neuraxis following spinal trauma. The possible mechanisms of tumor dissemination are discussed with a review of the literature.

[Laminectomy and extraction of nucleus pulposus for treatment of lumbar disc herniation: effect evaluation of over 10-year-followed-up]

OBJECTIVE

To investigate retrospectively the clinical effects and recurrence rate of 143 cases who underwent one level discectomy and followed up more than 10 years. To evaluate the outcome of patients in groups of different operating age and extents of disc herniation, and analyse whether difference exists in each group.

METHODS

There were 143 patients (operation time from January 1996 to December 2000) including 80 males and 63 females, aged from 18 to 66 years old with an average of 37.85 years. The followed-up time was 10 to 15 years with an average of 12.7 years. Patients were divided into 3 groups depends on operating age: < 30 years old, 30 to 50 years old and > 50 years old; 87 patients who's pre-operative CT scan could be collected among 143 cases were divided into 3 groups depends on extents of disc herniation: I degree, II degrees, and III degrees. The final followed-up was obtained in 2011, to evaluate each group and the holistic clincal outcome with JOA scores and ODI scores, and observe whether there were difference between every groups; to judge the effects by patient himself with modified Macnab Criteria.

RESULTS

(1) JOA scores pre-operation and final followed-up was 5.11 +/- 2.02 and 12.51 +/- 2.35 respectively; ODI scores pre-operation and final followed-up was 33.98 +/- 7.42 and 13.39 +/- 6.79 respectively. There were significant differences between pre-operative and final followed-up in JOA and ODI (P < 0.01). The excellent-good rate was 83.2% (119/143 ) according to modified Macnab Classification with recurrence rate of 6.3% at final follow-up. (2) Obvious difference was found in JOA scores in group who's age at operation less than 30 years old compared with other 2 groups at followed-up time, and no significant difference was found in JOA scores between other two groups ; no significant difference was found in ODI scores among the three groups. (3) Significant difference was found in JOA and ODI scores in group with III degrees lumbar disc herniation group compared with other 2 groups, and no statistical difference was found in clincal scores between other 2 groups.

CONCLUSION

(1) Long-term followed-up of 143 cases prove mono-level lumbar discectomy is an option for disc herniation with good curative effect and lower recurrent rate, the technique should be the prior selection in dealing with patients with lumbar disc herniation. (2) 51% patients (19/37) in group under 30 years old endure persistent low back pain. (3) The long-term clinical effects in patients with severe disc protrution who underwent lumbar discectomy is worse than those patients with mild lumbar disc herniation.

A simple technique of accessing the L5-S1 disc space for transforaminal endoscopic spine surgery

Transforaminal endoscopic spine surgery is increasingly used to treat a range of spinal conditions. The success of the surgery requires an accurate insertion of the guide needle and a precise placement of the working cannula and endoscope. However, such a precise placement is challenging for many surgeons to achieve when the pathology is located at the L5-S1 level. On the basis of our years of experience with performing transforaminal endoscopic spine surgery, we have developed a simple technique to help surgeons safely access the L5-S1 level. The technique has been proven intuitive and easy for experienced as well as inexperienced surgeons to learn. The key steps of the technique involve identifying an appropriate entry point on the skin and choosing an accurate trajectory angle for insertion. The purpose of this chapter is to report how to easily identify the entry point and choose a trajectory angle depending on the patient's anatomic characteristics.

Treatment of cervical adjacent segment pathology: a systematic review

STUDY DESIGN

Systematic review.

OBJECTIVE

To critically review and summarize evidence on the treatment of cervical adjacent segment pathology (ASP).

SUMMARY OF BACKGROUND DATA

Clinical ASP (CASP) refers to clinically significant symptoms and signs (radiculopathy, myelopathy, mechanical pain) that correlate with imaging evidence of degeneration at motion segments adjacent to a previous intervention. Despite growing awareness of the long-term risks of ASP, fusion is the most commonly performed type of cervical spine surgery. There are little data regarding the optimal treatment for cervical CASP.

METHODS

A systematic search of PubMed, the Cochrane Library, and Google Scholar for literature published through March 2, 2012, was conducted to answer 2 key questions: (1) What is the comparative effectiveness and safety of operative versus nonoperative treatments for cervical CASP?; and (2) Describe the outcomes of surgical treatment of cervical CASP.

RESULTS

A total of 5 studies were selected for inclusion. No comparative studies were found to answer question 1. We found 1 comparative study and 4 case series of more than 10 patients that addressed question 2: 2 studies described fusion (1 comparing discectomy with corpectomy), 2 evaluated laminoplasty, and 1 reported on use of artificial discs. No studies on use of laminectomy, foraminotomy, or posterior decompression and fusion were found. Two poor-quality (level of evidence III) retrospective cohort studies compared anterior cervical discectomy and fusion with corpectomy for the treatment of CASP, but 1 study was too small to draw meaningful comparisons and was considered a case series. The other reported a 37.5% risk difference favoring corpectomy; however, most patients in both treatment groups had excellent or good clinical results, and the study had significant methodological limitations that limit comparison of anterior cervical discectomy and fusion with corpectomy (nonrandomized allocation to treatment groups, limited follow-up, small numbers of patients). No studies describing subsequent development or advancement of ASP after reconstructive surgery were found.

CONCLUSION

Surgical options to treat cervical CASP include fusion, laminoplasty, and disc arthroplasty. There are no comparative data to guide operative versus nonoperative management. Favorable results are reported for each of these operative strategies, but small patient numbers and largely retrospective methodology limit definitive conclusions. There were conflicting data regarding the risk of single- versus multilevel fusion with respect to arthrodesis rates, and very low evidence that fusions at spinal levels caudal to ASP have a higher pseudoarthrosis risk compared with rostral levels.

CONSENSUS STATEMENT

1. Arthroplasty, laminoplasty, and fusion for treatment of cervical CASP were described in the studies found. These seem to be effective for treatment of cervical CASP. No studies on foraminotomy, laminectomy, and posterior decompression and fusion were found.

LEVEL OF EVIDENCE

Insufficient. Strength of Statement: Strong. Recommendation no.1: Despite the importance of this topic, a dearth of literature was found. We recommend further studies on this topic.

LEVEL OF EVIDENCE

Insufficient. Strength of Statement: Strong.

[Comparison of allogenic versus ostetic artificial bone in double door laminoplasty]

OBJECTIVE

To study the application of allogenic bone and Ostetic artificial bone in double door laminoplasty.

METHODS

From June 2004 to June 2010, a total of 111 patients underwent double door laminoplasty. And allogenic (group A, n = 63) and Ostetic artificial (group B, n = 48) bones were used. They had spinal stenosis at least several levels or OPLL (Ossification of posterior longitudinal ligament). Their follow-up period was 12 months. Anteroposterior compression ratio was used to evaluate the neurological status. Range-of-movement (ROM) of cervical spine and bone fusion was determined by radiography and computed tomography (CT) during the follow-ups.

RESULTS

Anteroposterior compression ratio: group A improved from 0.18 preoperation to 0.43 postoperation while group B increased from 0.20 preoperation to 0.44 postoperation; ROM: group A decreased postoperatively to (22.6 ± 3.3)° from (39.5 ± 6.1)° while group B decreased postoperatively to (22.9 ± 3.7)° from (39.3 ± 6.7)°. When Groups A and B were compared, bone fusion between allograft and spinous processes was completed in 73.1% vs 64.2%, partial fusion in 22.4% vs 18.7% and failed in 6.3% vs 17.1%.

CONCLUSION

Uses allogenic and Ostetic artificial bones in double door laminoplasty may achieve an excellent decompression of spinal cord. But the application of allogenic bone yields a higher bone fusion rate after surgery.

Unilateral laminotomy with bilateral decompression for lumbar spinal stenosis: short-term risks in elderly individuals

The aim of this retrospective study was to compare the short-term (4 weeks) surgical complications after unilateral laminotomy for bilateral decompression (ULBD) in patients with lumbar spinal stenosis, below and above age 65. Twenty-nine consecutive patients operated upon in 2011 were included: 12 below age 65, and 17 above age 65. Five complications (17.1%) were observed, all in the older age group: 3 dural tears, one root injury, and one subcutaneous collection requiring re-operation. The difference between groups was not statistically significant (p = 0.0521). Moreover, comparable or higher complication rates were noted after alternative techniques. The CRP level, obtained one day postoperatively, was lower than after alternative procedures, pleading for the limited invasiveness of ULBD. Old age seems to be associated with slightly elevated rates of short-term surgical complications, but without an increment in morbidity. Unilateral laminotomy for bilateral decompression does not carry an excessive risk in the elderly population.

[Comparison of effectiveness between laminoplasty and laminectomy decompression and fusion with internal fixation for cervical spondylotic myelopathy]

OBJECTIVE

To compare the clinical and radiographic outcomes between laminoplasty and laminectomy compression and fusion with internal fixation to treat cervical spondylotic myelopathy.

METHODS

Between September 2006 and September 2009, 143 cases of multilevel cervical myelopathy (the affected segments were more than 3) were treated by laminoplasty in 87 cases (group A) and by laminectomy decompression and fusion with lateral mass screw fixation in 56 cases (group B). There was no significant difference in gender, age, disease duration, pathological type, and affected segments between 2 groups (P > 0.05). The operation time, intraoperative blood loss, improvement of neurological function [Japanese Orthopaedic Association (JOA) 17 score], and the incidences of complications were observed; the cervical curvature index (CCI), range of motion (ROM), and symptoms of neck and shoulder pain [visual analogue scale (VAS) and neck disability index (NDI) scores] were recorded and compared.

RESULTS

There was no significant difference in operation time and intraoperative blood loss between 2 groups (P > 0.05). All patients were followed up 18-30 months (mean, 24 months). C5 nerve root palsy occurred in 4 cases (4.60%) of group A and in 5 cases (8.93%) of group B, showing no significant difference (chi2 = 0.475, P = 0.482). No complication of deep infection, pseudarthrosis, or screw loosening occurred. No closure of opened laminae was observed in group A; and no screw extrusion, breakage, or nerve injury was observed in group B. At last follow-up, neck axial symptoms appeared in 35 cases (40.23%) of group A and in 11 cases (19.64%) of group B, showing significant difference (chi2 = 6.612, P = 0.009). No significant difference was found in JOA score, CCI, ROM, or VAS scores between 2 groups at preoperation (P > 0.05); the JOA score, ROM, and VAS scores of groups A and B and CCI of group A at last follow-up were significantly improved when compared with preoperative ones (P < 0.05). No significant difference was found in the JOA score, improvement rate, and VAS score between 2 groups (P > 0.05); however, significant differences were found in ROM and CCI between 2 groups (P < 0.05). There were significant differences (P < 0.05) in pain intensity, lifting, work, reaction, driving, and total score between 2 groups at last follow-up.

CONCLUSION

Laminectomy decompression and fusion with internal fixation can effectively relieve pain, but it will greatly reduce the ROM; laminoplasty has less complications and satisfactory outcome. The two methods have similar effectiveness in the improvement of neurological function.

[Clinical application of centerpiece titanium plate fixation in open door laminoplasty]

OBJECTIVE

To explore the clinical application of Centerpiece titanium plate fixation in open door laminoplasty.

METHODS

From January 2009 to December 2010,25 patients with cervical spinal stenosis were treated by open door laminoplasty with Centerpiece titanium plate fixation. There were 16 males and 9 females,with a mean age of (57.2 +/- 6.7) years (ranged, 44 to75 years). There were multilevel cervical myelopathy in 8 cases, posterior longitudinal ligament ossification in 12 cases and congenital cervical spinal stenosis in 5 cases. According to Japanese Orthopedic Association (JOA) score to evaluate nerve function and calculate improvement rate. X-ray and CT were used to evaluate postoperative spinal canal enlargement and bone fusion at the hinge side. The sagittal diameter of C5 spinal canal on the lateral X-ray was measured before operation and 6 months after operation respectively, and the expansion rate of spinal canal was calculated [(postoperative sagittal diameter-preoperative sagittal diameter)/(preoperative sagittal diameter) x 100%].

RESULTS

The operative time and intraoperative blood loss were respectively (165.5 +/- 35.6) min and (325.0 +/- 75.1) ml. All patients were followed up from 6 to 18 months with an average of (7.3 +/- 3.8) months. The JOA score increased from 9.3 +/- 1.1 before operation to 14.7 +/- 2.1 at 6 months after operation (t = 4.12, P < 0.05), and the improvement rate was (64.5 +/- 10.2)%. Radiographic data showed spinal canal enlarged perfectly, bone fusion at hinge side and no cervical spinal stenosis was found. The sagittal diameter of C5 spinal canal improved from (9.0 +/- 1.5) mm before operation to (14.3 +/- 2.0) mm at 6 months after operation (t = 7.61, P < 0.05), and the expansion rate was (67.6 +/- 11.8)%.

CONCLUSION

Clinical application of Centerpiece titanium plate fixation in open door laminoplasty is safe and effective. While vertebral plate is elevated to obtain instantly stability, at the same time, the integrity of spinal canal is also recovered.

[Clinical application of lower cervical spinous process laminar screw technique in open door laminoplasty]

OBJECTIVE

To investigate the clinical outcomes of lower cervical spinous process laminar screw technique in open door laminoplasty.

METHODS

From February 2005 to June 2010,12 patients with cervical myelopathy were treated with open door laminoplasty by lower cervical spinous process laminar screw technique. There was intervertebral disc herniation with degenerative stenosis in 5 patients, ossification of posterior longitudinal ligament with osteophyte in 6 patients, cervical traumatic instability with spinal cord injuries in 1 patient. Nerve function, complications, and the cervical canal to body ratio (CBR), range of motion (ROM) and the anteroposterior serial alignment were observed by Japanese Orthopedic Association (JOA) score, X-ray, CT and MRI.

RESULTS

The surgical time was from 1.5 to 2 h with an average of 110 min; blood loss during operation was from 450 to 800 ml with an average of 580 ml. Postoperative complication occurred in 1 case with upper limb pain and 1 case with cerebrospinal fluid leakage. All patients were followed up from 1 to 2 years with an average of 21.8 months. JOA score improved from preoperative 9.5 +/- 1.8 to postoperative 13.6 +/- 2.4 (P < 0.01). X-ray, CT, MRI showed CBR increased obviously (P < 0.01); ROM on flexion-extension and cervical lordosis decreased respectively from (40.0 +/- 10.0) degrees and (65.0 +/- 12.0)% before operation to (15.0 +/- 5.0) degrees and (42.0 +/- 8.0) % at the final follow-up (P < 0.01).

CONCLUSION

Lower cervical spinous process laminar screw technique in open door laminoplasty for cervical syndrome is safe and can obtain satisfactory effects, has strong internal fixation and reduce the risk of re-closure.

Lumbopelvic fixation for multiplanar sacral fractures with spinopelvic instability

Sacral fractures with both transverse and bilateral vertical fracture components are by definition multiplanar fractures, and often present with spinopelvic instability and cauda equina deficits. The treatment is challenging. Between 2006 and 2009, we treated nine such patients at our trauma centre. There were six men and three women, with a mean age of 32.2 years. Preoperative neurologic deficits were noted in seven patients; four patients had complete cauda equina paralysis, and three patients had incomplete cauda equina syndrome. All patients were treated using lumbopelvic instrumented fixation without other devices for their multiplanar sacral fractures. Six patients who had neurological deficits and sacral canal compression underwent decompression laminectomy. The mean postoperative follow-up time was 21.7 months (range, 14-32 months). All fractures went on to union without loss of reduction or hardware failure. The mean Gibbons score improved from 3.5 preoperatively to 2.3 postoperatively among the patients who underwent decompression laminectomy. Eight out of nine patients had fair or better results based on radiographic criteria and the Majeed pelvic fracture outcome score. Our experience suggests lumbopelvic fixation can be used for the treatment of multiplanar sacral fractures with spinopelvic instability with a low rate of complications. Neurologic improvement can be expected, but whether surgical decompression results in substantially better neurologic recovery than conservative treatment remains uncertain.

[Analysis of axial symptoms after indirect decompression for ossification of the posterior longitudinal ligament of the cervical spine]

OBJECTIVE

To study the etiology and clinical significance of axial symptoms after posterior operative procedures for ossification of the posterior longitudinal ligament (OPLL).

METHODS

From February 2005 to February 2010, 76 patients with OPLL treated were retrospectively experienced. There were 34 male and 42 female with average of 52.1 years (range from 37 to 74 years), the average duration of the disease was 32.1 months (range from 11 to 56 months). Nineteen patients underwent traditional laminectomy in group A, 33 patients received open-door laminoplasty in group B and 24 patients underwent lateral mass screw fixation in group C. All patients underwent X-ray examination pre- and post operative, computed tomography were used for diagnosis of OPLL, the recovery rate was calculated using pre- and postoperative Japanese Orthopedic Association (JOA) scores for each patient. Pre- and postoperative cervical curvature index and axial symptoms were measured and compared. χ(2) test and SNK test were used as statistical methods.

RESULTS

All patients were followed up for 14 - 35 months, average (21 ± 5) months. Loss of cervical curvature index was 4.2% ± 1.7% in group A, 2.9% ± 2.2% in group B and 2.3% ± 1.9% in group C. The difference was significant in loss of cervical curvature indice between group A and B (q = 2.94, P < 0.01), group A and C (q = 4.23, P < 0.01). The average JOA recovery rate was 58.3% for group A, 64.3% for group B and 66.7% for group C. There was no significant difference in JOA recovery rate among the three groups (P > 0.05). The rate of early evident axial symptoms was 7/19 in group A, 30.3% in group B and 33.3% in group C and the difference was not statistically significant (P > 0.05). The incidence of late evident axial symptoms was 5/19 in group A, 12.1% in group B and 8.3% in group C, the difference was not significant between group B and C (χ(2) = 13.762, P < 0.01), but of statistical difference between group A and B(χ(2) = 6.368, P < 0.01), group A and C (χ(2) = 11.481, P < 0.01). No kyphotic deformity in the group A, no "Close Door" phenomenon in group B and no internal failure in group C.

CONCLUSION

The incidence of early axial symptoms are of no significant difference among the three groups, but late axial symptoms are higher in the laminectomy than other groups, which may be associated with loss of cervical lordosis.

[Biomechanical research on different pairs of lumbar laminectomy with finite element analysis]

The finite element model of the intact lumbar spine (L1-L5) was set up to study the biomechanical changes of three different pairs of the lumbar laminectomy. The three-dimensional finite elements model of L1-L5 vertebrae structure was constructed by the combination of self-compiled software and Hyper Mesh. The finite element model was compared with the experimental data in vitro. The finite element model was modified of stenosis at L3-L4 and L4-L5 with the same boundary conditions and physical loads to study the motion and loading in the annulus changes at the surgical site as a result of surgical alteration. The study suggested that the removal of posterior lumbar spinal elements for the treatment of stenosis at L3-L4 and L4-L5 produced a graded increase in motion at the surgical site, with the greatest changes occurring in flexion-extension and axial rotation and that during lateral bending the amount of resection was only slightly affected. The data showed that for flexion-extension and axial rotation the increases in motion were correlated to the extent of posterior element removal. It is necessary to retain the greatest degree of posterior lumbar structures in thorough decompression, which can further reduce the postoperative intervertebral disc, facet degeneration.