Aims. Developmental cervical spinal stenosis (DcSS) is a well-known predisposing factor for degenerative cervical myelopathy (DCM) but there is a lack of consensus on its definition. This study aims to define DcSS based on MRI, and its multilevel characteristics, to assess the prevalence of DcSS in the general population, and to evaluate the presence of DcSS in the prediction of developing DCM. Methods. This cross-sectional study analyzed MRI spine morphological parameters at C3 to C7 (including anteroposterior (AP) diameter of spinal canal, spinal cord, and vertebral body) from DCM patients (n = 95) and individuals recruited from the general population (n = 2,019). Level-specific median AP spinal canal diameter from DCM patients was used to screen for stenotic levels in the population-based cohort. An individual with multilevel (≥ 3 vertebral levels) AP canal diameter smaller than the DCM median values was considered as having DcSS. The most optimal cut-off canal diameter per level for DcSS was determined by receiver operating characteristic analyses, and multivariable logistic regression was performed for the prediction of developing DCM that required surgery. Results. A total of 2,114 individuals aged 64.6 years (SD 11.9) who underwent surgery from March 2009 to December 2016 were studied. The most optimal cut-off canal diameters for DcSS are: C3 < 12.9 mm, C4 < 11.8 mm, C5 < 11.9 mm, C6 < 12.3 mm, and C7 < 13.3 mm. Overall, 13.0% (262 of 2,019) of the population-based cohort had multilevel DcSS. Multilevel DcSS (odds ratio (OR) 6.12 (95% CI 3.97 to 9.42); p < 0.001) and male sex (OR 4.06 (95% CI 2.55 to 6.45); p < 0.001) were predictors of developing DCM. Conclusion. This is the first MRI-based study for defining DcSS with multilevel canal narrowing. Level-specific cut-off canal diameters for DcSS can be used for early identification of individuals at risk of developing DCM. Individuals with DcSS at ≥ three levels and male sex are recommended for close monitoring or early intervention to avoid traumatic spinal cord injuries from stenosis. Cite this article: Bone Joint J 2024;106-B(11):1333–1341

Aims. This study aimed to determine the relationship between pedicle-lengthening distance and bulge-canal volume ratio in cases of lumbar spinal stenosis, to provide a theoretical basis for the extent of lengthening in pedicle-lengthening osteotomies. . Methods. Three-dimensional reconstructions of CT images were performed for 69 patients (33 men and 36 women) (mean age 49.96 years; 24 to 81). Simulated pedicle-lengthening osteotomies and disc bulge and spinal canal volume calculations were performed using Mimics software. . Results. The mean spinal canal volume of the two groups, L4 and L5, were 14 646.81 mm. 3. (5918.60 to 22 717.77) and 16 408.47 mm. 3. (8678.21 to 31 204.79), respectively. The mean lengthening distance was 2.17 mm (0.5 to 4.8) and the mean bulge-canal volume ratio was 0.23 (0.05 to 0.48). The pedicle-lengthening distance of the two groups were very strongly correlated with disc bulge volume and bulge-canal volume ratio (p < 0.001); the predictive equation was established as L = 0.06 + 9.06R (where L equals the pedicle-lengthening distance and R represents the bulge-canal volume ratio). . Discussion. Our findings indicated that lumbar pedicle-lengthening distance strongly correlates with bulge-canal volume ratio, which can be estimated before surgery from CT images. Take home message: The predictive equation could help surgeons to decide the pedicle lengthening distance according to individual's condition and guide the surgery effectively. Cite this article: Bone Joint J 2016;98-B:238–43

Objectives. Pedicle-lengthening osteotomy is a novel surgery for lumbar spinal stenosis (LSS), which achieves substantial enlargement of the spinal canal by expansion of the bilateral pedicle osteotomy sites. Few studies have evaluated the impact of this new surgery on spinal canal volume (SCV) and neural foramen dimension (NFD) in three different types of LSS patients. Methods. CT scans were performed on 36 LSS patients (12 central canal stenosis (CCS), 12 lateral recess stenosis (LRS), and 12 foraminal stenosis (FS)) at L4-L5, and on 12 normal (control) subjects. Mimics 14.01 workstation was used to reconstruct 3D models of the L4-L5 vertebrae and discs. SCV and NFD were measured after 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm pedicle-lengthening osteotomies at L4 and/or L5. One-way analysis of variance was used to examine between-group differences. Results. In the intact state, SVC and NFD were significantly larger in the control group compared with the LSS groups (P<0.05). After lengthening at L4, the percentage increase in SCV (per millimetre) was LRS>CCS>FS>Control. After lengthening at L5 and L4-L5, the percentage increase in SCV (per millimetre) was LRS>FS>CCS>Control. After lengthening at L4 and L4-L5, the percentage increase in NFD (per millimetre) was FS>CCS>LRS>Control. After lengthening at L5, the percentage increase in NFD (per millimetre) was CCS>LRS>control>FS. Conclusions. LRS patients are the most suitable candidates for treatment with pedicle-lengthening osteotomy. Lengthening L4 pedicles produced larger percentage increases in NFD than lengthening L5 pedicles (p < 0.05). Lengthening L4 pedicles may be the most effective option for relieving foraminal compression in LSS patients. Cite this article: P. Li, L. Qian, W. D. Wu, C. F. Wu, J. Ouyang. Impact of pedicle-lengthening osteotomy on spinal canal volume and neural foramen size in three types of lumbar spinal stenosis. Bone Joint Res 2016;5:239–246. DOI: 10.1302/2046-3758.56.2000469

The capacity of the lumbar spine canal has direct relation to space-compromising conditions. Primary narrowing of the canal may produce no symptoms, but a slight reduction in capacity as a result of degenerative lesions, age, or disc bulging may result in symptomatic spinal canal stenosis. We studied the dimensions in the adult Greek population in order to find the variability factor in the capacity of the lumbar spinal canal. The dimensions of the lumbar spinal canal were measured in 27 adult men and 42 adult women, all under the age of 50. MRI was used to measure four levels of the spine (L2 through L5). The AP and transverse diameters, as well as the cross section area, were measured at each level. Mean age (sd) of females was 34.8 (6.8) years. Mean age for males was 35.2 (7.3) and was comparable to women (P0.8). Mean age of a third group of 11 males over the age of 50 was 54.5 (2.6). All individuals included in the study were healthy and without any apparent degenerative changes in the lumbar spine or any symptoms related to it. Hotelling’s tests (Anderson, 1958), in terms of multivariate measurements of the spinal canal, were used to compare both genders and the two age levels. Tests for trends in the lumbar levels L2 through L5 were based on the exact binomial distribution for the number of cases exhibiting a complete trend from L2 to L5. The reported significance levels are adjusted for multiplicity of tests. The relation of spinal width to lumbar levels is shown separately for the groups of males and females women under the age of 50 and for the group of males under over the age of 50. In all four lumbar levels, the group of men over 50 years old had a narrower spinal canal compared with men under 50 years old (2=0.005). This was particularly evident in levels L2 and L5 where the spinal canal for older men was narrower by factors of 15.5% and 13.1%, respectively. In the two gender groups of comparable age, spinal width was found to differ between men and women (2< 0.0001). In particular, the females had a wider spinal canal than males in levels L2, L3 and L4 and a narrower canal in level L5. Spinal width was found to exhibit a decreasing trend in lumbar levels L2 through L5. The evidence for this trend was strong for all three groups: females under the age of 50 (P< 0.0001), men under 50 (2< 0.005), and the older men (P< 0.0001). A similar trend was present for the anteroposterior diameter, as well as for the Transverse diameter. A numerical summary (mean, sd) of all spinal measurements is reported. We believe this study to be an important one that provides useful information regarding the capacity of the lumbar spinal canal, thus helping the surgeon to properly evaluate the stenotic patient

A new technique of enlargement of the lumbar spinal canal (ELSC) and neural decompression in the treatment of any uni or multilevel segmental pathology causing stenosis with radicular or dural sac compression was performed by a standard laminectomy, posterior osteophytectomy and radical discectomy, leading to a widening of all the saggital and coronal sizes of the spinal canal, including the foraminal outlet of the root. No damage or excessive excision of facet joints are necessary to achieve the wide neural decompression. The outcome of patients that underwent conventional laminectomy and discectomy (Group A) and ELSC ( Group B) was compared. The only objective parameter used to compare between the groups was only the need for reoperation of the patients. The indications for the first surgery or a second reoperation (revision) were identical for both groups. Conventional laminectomy and discectomy (Group A) was performed in 317 patients between 1977 and 1989. In this group 193 (61%) were females and 124 (39%) males. Mean age 42.5 years (range 13 to 72). In this group reoperation at the same level was necessary in 24 patients (8%). ELSC (Group B) was performed in 231 patients between 1990 and 2002. In this group 133 (58%) were females and 98 (42%) males. Mean age 46.5 years (range 17 to 78). Only 3 patients needed reoperation at the same level in this group (1.3%). Using CT-scan cross sectional area measurements , the spinal canal was seen to be enlarged by 217% in average by using the ELSC surgical technique. The follow up for group A was from 1 to 8 years; group B was 3 to 11 years. All patients underwent the operations by the autor. Generous posterior osteophytectomy, scurving the anterior wall of the foramina in both sides, bypasses the pathway of the root, resulting in release of the overtensed, elongated and compressed nerve root at the encroached site of the foraminal outlet. An optimal enlargement of the lumbar spinal canal was achieved without affecting the spinal stability. No symptoms related to perineural scarring were seen in Group B. The ELSC technique can be aplied together with any kind of spinal instrumentation

In normal, physiological circumstances there is ample room in the spinal canal to accommodate the spinal cord. Our study aimed to identify the degree of compromise of the spinal canal which could be anticipated in various atlantoaxial pathological states. We examined paired atlas and axis vertebrae using high-definition radiography and simultaneous photography in both normal and simulated pathological orientations in order to measure the resultant dimension of the spinal canal and its percentage occlusion. At the extreme of physiological axial rotation (47°) the spinal canal is reduced to 61% of its cross-sectional area in neutral rotation. The spinal cord is thus safe from compromise. Atlantoaxial subluxation of up to 9 mm reduces the area of the spinal canal, in neutral rotation, to 60% with no cord compromise. Any rotation is, however, likely to cause cord compression. The mechanism of fixation in atlantoaxial rotatory subluxation could be explained by bony interlocking of the facet joint, reproducible in dry bones

Objectives: To evaluate and compare the imaging of lumbar spinal canal stenosis using plain radiographs, CT-Myelogram and MRI. Patients and Methods: Prospective study at Medical College Calicut during 2002-2004. 25 patients of age from 25 to 69 years, with clinical features of lumbar spinal canal stenosis were evaluated. Inter pedicular distance, anteroposterior diameter and thecal sac cross sectional area (IPD, APD and TSCA) were measured using plain radiographs, CT-Myelogram and MRI, in all 25 patients. Results: Soft tissue compression evaluated as disc protrusion and ligamentum flavum hypertrophy detected in 20 patients by CT-myelography and 22 patients by MRI. Thecal sac cross sectional area at stenosed level were assessed and compared with CT- Myelography and MRI, out of 25 patients 10 and 11 patients were detected with significant narrowing by CT-Myelogra-phy and MRI respectively in which 2 cases of severe thecal sac compromise (< 76 mm2) detected by CT-Myelography and 3 cases by MRI. CT–Myelography detected one case of single level absolute stenosis (AP diameter of < 10mm), but none of the cases were detected by MRI or Plain radiography. Relative stenosis (AP diameter of 10-12mm) at single level detected in 6 cases by CT–Myelography, in 4 cases by MRI and in 3 cases by plain radiography. Relative stenosis at multiple level detected in 3 cases by CT–Myelogra-phy, in 4 cases by MRI and in 6 cases by plain radi-ography.4 cases of multilevel absolute stenosis were detected by all 3 modalities. Conclusions: CT- Myelographic measurement are well correlating with clinical symptoms and MRI findings. Bony Canal measurements obtained by CT- myelogra-phy are superior to same measurements obtained by MRI. Thecal-sac cross sectional area measurements obtained by CT-Myelography is comparable with that of MRI, even though soft tissue involvement in lumbar spinal canal stenosis is more clearly detected by MRI. In comparison of AP diameter taken by plain radiograph and CT- Myelography, X-ray measurements shows only 50-60% accuracy. AP diameter in CT- Myelography and MRI were comparable, when the thecal-sac cross sectional area measured by MRI taken as gold standard (using Karl pearsons correlation coefficients). CT-Myelography shows sensitivity of 92% and specificity of more than 96%

Summary Statement. Bilaretal epiphysiodesis of he neurocentral cartilages causes shortening of the sagittal length of the pedicles and a subsequent spinal stenosis at the operated segments, resembling that found in patients with achrondroplasia. Introduction. The introduction of pedicle screws in the immature spine may have implications for the growth of the vertebra. The effect of blocking the growth of neurocentral cartilage (NC) is not yet fully defined. Block hypothetically leads to a bilateral symmetrical alteration of the vertebral growth. Using an experimental animal model, our goal is to analyze if a bilateral epiphysiodesis of the NC using pedicle screws is able to induce narrowing of the spinal canal in the thoracolumbar spine. Experimental animals and Methods. A total of 24 domestic pigs were operated on by bilateral blocking of the NC using pedicle screws. The animals were divided into 4 groups depending on the level of blockage: A, low thoracic levels; B, thoracolumbar transitional hinge; C, upper lumbar spine; and D, blocking of the caudal lumbar level below L5 segment. Different morphological, morphometric and standard radiological parameters were analyzed at the thoracic and lumbar vertebrae of the animals. The deviation from the physiological parameters was established by comparing all parameters obtained in the NC-blocked animals with those acquired in 14 pigs without NC blocking. These animals were considered as the control group. Results. None of the animals that underwent NC epiphysiodesis showed asymmetrical spinal growth inducing deformities in the coronal plane. There was neither rotation nor wedging of the vertebral bodies. Whatever the level involved, NC epiphysiodesis caused shortening of the sagittal length of the pedicles and a subsequent decreasing of the antero-posterior diameter of the spinal canal. These features resulted in a frank spinal stenosis at the operated levels. However, the transverse diameter of the spinal canal was conserved in the coronal plane. In the sagittal plane, blocking of the neurocentral cartilage conditioned a lumbar hyperlordosis with compensatory kyphosis of the upper level to the operated vertebra. Conclusions. Symmetrical growth arresting of neurocentral cartilages induces a narrow spinal canal by decreasing the sagittal diameter similar to that observed in patients with achondroplasia. The most affected structure was the development of the vertebral pedicles

The oblique sagittal diameter of the lumbar spinal canal was measured by diagnostic ultrasound in seventy-three patients with symptomatic disc lesions, and compared with measurements from 200 asymptomatic subjects. Results suggest that the available space in the spinal canal is highly significant in the symptomatology of disc lesions, and in the patient's response to treatment

The vertebral canal reaches maturity early in life. The size of the lumbar spinal canal was evaluated to determine normal values for vertebral canal size. For our prospective cross-sectional study 95 women with a singleton pregnancy between 16 and 41 weeks of gestation were recruited during their routine anomaly scan. After defining the region of interest on the 2D ultrasound image, volume scanning was performed and the rendered volume was displayed in three orthogonal planes on the screen. Area and volume of the vertebral canal in L1, L3 and L5 were calculated. Area and volume of the vertebral canal showed a close correlation to gestational age. Advancing gestational age was characterised by a statistically significant increase in all volumetric and conventional 2D measurements. No major differences regarding area and volume measurements could be found between upper and lower spine. Sonographic evaluation of the fetal spine plays an important role in obstetric anomaly scans. Prenatal diagnosis may also lead to interesting aspects concerning back pain in adults. A small vertebral canal is considered to be one of the causes for back pain in later life but these syndromes are multi-factorial. Since interpedicular diameter of the spinal canal at the level of L1-L4 at birth is approximately 70 % of the adult size, any kind of intrauterine growth impairment will affect further development. Further data will show if our normal values will have significance in the early detection of disorders of the vertebral canal

A method is described of measuring the lumbar spinal canal by pulsed echo ultrasound. It is simple, safe and has a high degree of accuracy. The lumbar canal has been measured in over 800 subjects including 100 mining recruits and fifty nurses between the ages of fifteen and eighteen years. Ultrasound can demonstrate the degree and extent of bony stenosis. It may have value in preventive medicine, identifying the subject at risk

Introduction. There is an unresolved controversy in the published work about the effect of screws crossing the neuro-central cartilage (NCC) on spinal canal dimension in very young children and in animals. Anterior vertebral body screws with fusion can invade and damage the NCC, especially at the site of screw insertion; however, this finding has never been studied. Methods. This study is a retrospective, clinical and radiological analysis of seven consecutive children aged 1–2 years treated with anterior vertebral instrumentation and fusion by downsized rod screw systems. The mean age at time of surgery was 2 years 4 months (range 1 year 9 months to 2 years 10 months). The average follow-up period was 3 years 3 months (2 years 6 months to 4 years 5 months). 16 screws inserted anteriorely were evaluated by a follow-up CT scan. Spinal canals were divided with known anatomical landmarks into right and left hemicanals. The relation of the anterior screws to the NCC and the spinal canal dimension were studied. All clinical and radiological complications were recorded. Results. Only 11 screws were suitable for measurement. There was a difference of 10–20% between the surface areas of the two hemicanals in six levels in which the screw heads were passing through or encroaching on the NCC; the canal was smaller ipsilateral to the affected NCC. The hemicanals were almost symmetrical in five levels in which the screw heads were away from the NCC, except in one in which it was touching the NCC. For the 16 screws evaluated there were no recorded complications apart from one screw breaching the adjacent end plate. Conclusions. Anterior vertebral body screws with fusion can encroach on the NCC when inserted in very young children, which seems to decrease the ipsilateral canal dimension between 10% and 20%. Apart from this finding, anterior instrumentation is safe when used in very young children aged 1–2 years. Canal asymmetry had no clinical effect in childhood; however, long-term follow-up of these children is needed to measure its clinical significance. Change of screw position with time is a frequent occurrence in the distal pedicle screws with single growing rods. There are two different types identified. With growing rods some degree of distal pedicle screw migration in this paediatric age group may not be regarded as a complication of treatment

Posterior approach to the lumbar spine necessarily induces structural damage of paravertebral muscles. In order to avoid these changes, we have started to utilize a microscopic decompression of the spinal canal via an unilateral approach since 1998. The purpose of this study was to evaluate the results of this operative procedure for lumbar spinal canal stenosis. A total of 18 patients, 13 men and five women, were reviewed. The age at the time of surgery ranged from 53years to 78years with a mean of 69.0years. Follow up period averaged 12.3months ranging from one to 32months. As for operative procedure, unilateral paravertebral muscle was retracted laterally and lam-inotomy in the approached side was performed. Following complete decompression of a nerve root in the approached side, microscope was tilted and the inner aspect of lamina in the contralateral side was resected using high-speed drill with a guard of yellow ligament to dural sac and nerve root. Following the procedure, yellow ligament was resected and nerve root in the contralateral side was decompressed. Results: In operation time, blood loss and recovery rate of JOA score, there were no statistical differences compared with ordinal laminotomy cases. Dural sac was well decompressed not only in the hemilaminec-tomy side but also in the contralateral side. All cases showed intensity change of paravertebral muscle in the approached side on T2 weighted MRI. Conclusion: The procedure described here was definitely effective because paravertebral muscle in the contralateral side and midline structure of the lumbar spine could be completely preserved

Introduction: We report the outcome two years following Dynesys for the treatment of Spinal Canal Stenosis. In both the FDA trial and the European multicentre study, stenosis was invariably combined with decompression, invalidating conclusions on the results of Dynesys alone. Method: Eighteen patients had symptomatic Spinal Canal Stenosis with root claudication sufficient to justify surgical intervention. Average age of patients was 68 with a range between 44–86 years. Dynesys was applied for the treatment of a single level in 4, two levels in 8, and more than two levels in 6. Patients were evaluated preoperatively using ODI, SF36, VAS, plain x-ray, MRI scanning & discography. Questionnaires were evaluated at the first and second years. Results: 2 patients had undergone previous spinal decompression, and decompression at the time of Dynesys surgery in 7. In the remaining 9 cases, no decompression was used, relying on distraction alone as in the X stop system. In this latter group, stenotic symptoms failed to resolve. Removal of Dynesys was indicated in 3 (16.6%). Discussion & Conclusions: Dynesys alone is not recommended as a treatment for symptomatic spinal stenosis. A separate study is required to address the question of whether Dynesys adjunct improves the back pain outcome compared with decompression alone

Purpose: There are a wide variety of operative procedures for lumbar spinal canal stenosis. Bilateral fenestration, preserving the continuity of the lamina and spinous processes, has widely been employed in our department and its affiliated hospitals. The following questions are raised: Are decompressive effects of fenestration and spinal stability maintained without spinal fusion or instrumentation? In order to answer the questions, we compared the rates of revision after fenestration with those after laminectomy alone and decompressive surgery with spinal fusion. Materials and methods: The registry of spinal surgeries of our university and affiliated hospitals from 1988 to 1997 was consulted. During the first 5-years period 1159 patients underwent decompressive surgery. 908 of them had spondylosis and 251 had degenerative spondylolisthesis (DO) as a contributing factors of neural compression. Fenestration was done in 740 (81%) of patients with spondylosis and in 176 (70%) of patients with DO. Results: Regarding the whole series 31 out of 1159 patients had a revision. The revision rate was 2.7%. 15 out of 908 patients (1.7%) with spondylosis and 16 out of 251 patients (6.4%) with DO underwent revisions. 11 out of 740 (1.5%) with spondylosis and 11 out of 176 (6.3%) with DO underwent revisions after fenestration. No significant differences were found among the revision rate of fenestration, laminectomy and decompressive surgery with spinal fusion. Conclusion: The decompressive effect of fenestration was maintained long enough, even for degenerative spondylolisthesis. As a first operation spinal fusion is not necessarily indicated for lumbar canal stenosis

This study reports on postoperative changes of intra and epidural space of both degenerative lumbar spinal canal stenosis(DLSCS) and degenerative spondylolisthesis(DO)on MRI. 48cases(DLSCS:20cases, DO:28cases)were investigated in this study. All cases performed bilateral wide fenestration. The average age of these patients was 65 years and average follow-up period was 60 months. The average improvement ratio(%) of JOA score was 68% at the last follow-up. Symptomes had deteriorated in 8 cases, according to an increase in the volume of the postlaminectomy membrane, at the last follow-up. There were 8 cases(29%)in DO. showing an increase of % slip on X-ray at the last follow-up, accompanied with both a slight decreasing of the cross-sectional area(CSA)of dural sac and a slight deterioration of clinical results. Discussion: Symptomes in around 17% of the cases deteriorated, and there were three factors on MRI ; a poor expansion of the dural sac, a grouping of the cauda equina, and a decrease in the CSA of the dural sac

Study design: Retrospective, descriptive study. Objectives: To describe the characteristics and outcomes of patients with spinal canal stenosis who suffer significant spinal cord injury (SCI) due to hyperextension injury of the cervical spine. To compare their characteristics and outcomes with all patients suffering traumatic cervical SCI and with the total cohort of patients admitted to a Spinal Injuries Unit for rehabilitation. Setting: Spinal Injuries Unit (SIU), Princess Alexandra Hospital, Brisbane. Methods: Demographic, injury and outcome data were obtained from an existing database and by review of the medical records of 575 patients admitted to and discharged from the SIU between July 1st, 1995 and July 1st 2002. Main outcome measures were: change in American Spinal Injury Association (ASIA) scale category, change in ASIA motor score, discharge Functional Independence Measure (FIM) score and change in FIM score, length of stay (LOS), primary means of mobility at discharge and discharge destination. Standard statistical methods were used to compare groups. Results: A total of 18 (3%) of the 575 patients were found to have cervical canal stenosis and hyperextension injury (the CCS/HI group). This represents 8% of the total group suffering traumatic injury to the cervical spinal cord (the total cervical trauma: TCT group, n = 225). This CCS/HI group was found to have a mean age at injury of 55.1 years compared to 37.1 and 37.8 years respectively for the TCT and total groups. Ninety-four percent of patients were found to have a neurological level at admission at C1–3 or C4–5 compared to 75.6% of the TCT group and only 5.6% of patients had an ASIA Impairment Category A lesion at admission compared to 38.7% of the TCT group. Falls (55.6%) was the most common cause of injury in the CCS/HI group with motor vehicle accidents (33.8%) most common in the TCT group. The mean change in ASIA motor score between admission and discharge was 34.7 compared to 20.4 for the TCT group. Degree of impairment (measured by a change in ASIA Category) improved in 28% of patients and mean change in total FIM score was 41.3. There was no difference seen with the TCT group. LOS was shorter for these patients (111.1 days vs. 161.6 days). The primary means of mobility at discharge was “walking” for 50% of this group (compared to 28.4% for the TCT group) while the next most common means of mobility was “power wheelchair” at 28% (17% of TCT group). Most patients (55.4%) were discharged to their previous home following rehabilitation and 22.3% were discharged to another rehabilitation unit or acute hospital. Conclusions: Patients with cervical spinal canal stenosis who suffer hyperextension injury constitute a distinct subgroup with the total group of traumatic cervical spinal cord injuries. This study suggests that they are older at the time of injury, have more rostral cervical injuries, are more likely to have incomplete injuries and that falls is the most common cause of injury. They have greater improvement in motor function but this does not appear to result in greater function at discharge as measured by the FIM. There appears to be a dichotomy with results for mobility at discharge with patients either being able to walk or requiring a power wheelchair. LOS in the SIU is shorter but a higher percentage are discharged to another hospital or rehabilitation unit

STUDY DESIGN: Retrospective, descriptive study. OBJECTIVES: To describe the characteristics and outcomes of patients with spinal canal stenosis who suffer significant spinal cord injury (SCI) due to hyperextension injury of the cervical spine. To compare their characteristics and outcomes with all patients suffering traumatic cervical SCI and with the total cohort of patients admitted to a Spinal Injuries Unit for rehabilitation. SETTING: Spinal Injuries Unit (SIU), Princess Alexandra Hospital, Brisbane. METHODS: Demographic, injury and outcome data were obtained from an existing database and by review of the medical records of 575 patients admitted to and discharged from the SIU between July 1st, 1995 and July 1st 2002. Main outcome measures were: change in American Spinal Injury Association (ASIA) scale category, change in ASIA motor score, discharge Functional Independence Measure (FIM) score and change in FIM score, length of stay (LOS), primary means of mobility at discharge and discharge destination. Standard statistical methods were used to compare groups. RESULTS: A total of 18 (3%) of the 575 patients were found to have cervical canal stenosis and hyperextension injury (the CCS/HI group). This represents 8% of the total group suffering traumatic injury to the cervical spinal cord (the total cervical trauma: TCT group, n = 225). This CCS/HI group was found to have a mean age at injury of 55.1 years compared to 37.1 and 37.8 years respectively for the TCT and total groups. Ninety-four percent of patients were found to have a neurological level at admission at C1-3 or C4-5 compared to 75.6% of the TCT group and only 5.6% of patients had an ASIA Impairment Category A lesion at admission compared to 38.7% of the TCT group. Falls (55.6%) was the most common cause of injury in the CCS/HI group with motor vehicle accidents (33.8%) most common in the TCT group. The mean change in ASIA motor score between admission and discharge was 34.7 compared to 20.4 for the TCT group. Degree of impairment (measured by a change in ASIA Category) improved in 28% of patients and mean change in total FIM score was 41.3. There was no difference seen with the TCT group. LOS was shorter for these patients (111.1 days vs. 161.6 days). The primary means of mobility at discharge was “walking” for 50% of this group (compared to 28.4% for the TCT group) while the next most common means of mobility was “power wheelchair” at 28% (17% of TCT group). Most patients (55.4%) were discharged to their previous home following rehabilitation and 22.3% were discharged to another rehabilitation unit or acute hospital. CONCLUSIONS: Patients with cervical spinal canal stenosis who suffer hyperextension injury constitute a distinct subgroup with the total group of traumatic cervical spinal cord injuries. This study suggests that they are older at the time of injury, have more rostral cervical injuries, are more likely to have incomplete injuries and that falls is the most common cause of injury. They have greater improvement in motor function but this does not appear to result in greater function at discharge as measured by the FIM. There appears to be a dichotomy with results for mobility at discharge with patients either being able to walk or requiring a power wheelchair. LOS in the SIU is shorter but a higher percentage are discharged to another hospital or rehabilitation unit

Lumbar disc herniations are quite common pathology in orthopedics. Percutaneous discectomy remains somewhat controvercial. It has limited indications and has not proven to be as effective as conventional or microscopic discectomy. Smith and Foley developed a new minimum invasive procedure for lumbar disc disease, Microendoscopic Discectomy (MED) in 1995. We started MED from October 1998. Besides, we started the clinical application of MED for lumbar spinal canal stenosis from February 2000. The purpose of the presentations are to present operative technique, early clinical results and complications. A) We operated upon 40 patients of MED from October 1998 to July 2000 for lumbar disc herniations. Male were 25, female were 15, and mean age was 38 years (15~64). In one patient, operated disc level was L2/3, in 21, L4/5, in 16, L5/S, and in two L4/5/S. Methods: We investigated: period of hospital stay, period of hospital stay postoperation, period to return to normal temperature, frequency of postop. NSAID, operation time, blood loss, period to begin to walk, JOA score, period to return to work or school, and complications. Results: The mean hospital stay was 17.9 days, the mean hospital stay postop. 9.7 days, period to return to normal temperature 1.3 days, frequency of postop. NSAID 1.1 times. The mean operation time was 105 ± 42 minutes, (65–180 min). The mean blood loss was 9.7 ± 18.5 Gm. (uncountable~ 120Gm.). All patients began to walk one day postoperatively. Mean JOA score was improved from 10.7 ± 3.8 preop. to 27.6 ± 0.9 4w. postop, to 28.1 ± 0.7 12w. postop., to 28.7 ± 0.6, 24w. postop. The mean period to return to work or school was 22.3 days. In one case, we had liquorrhea, and the damaged dura had to be repaired. B)We operated upon five patients of decompression by MED for lumbar spinal canal stenosis from February 2000 to July 2000. Male were one, female were four, and mean age was 72 years (65–77). In four patient, operated disc level was L4/5, in one, L5/S. We will show the operative procedures by videotape. We investigated – operation time, blood loss, period to begin to walk, JOA score, and complications. Results: The mean operation time was 128+−31 minutes, (85m–170m.). The mean blood loss was 25 ± 29 Gm. (uncountable – 70Gm.). All patients began to walk one day postoperatively. Mean JOA score was improved from 15.7 ± 3.3preop. to 27.5 ± 0.5 4w. postop, to 28.0 ± 0.7 12w. postop.. There was no complication. Discussion: The advantages of MED are small skin incision, less invasion to paravertebral muscles, short bed rest, and rapid return to work. The disadvantages are loss of deep perception and technical demands. To overcome the disadvantages, we are developping the 3D MED, and we are organizing live pig seminar biannually. Conclusion: MED has several advantages i,e, small skin incision, less invasion to paravertebral muscles, short bed rest, and rapid return to work. We need proper knowledge and technique about endoscopic surgery, and laboratory training by live pig and cadaver. MED can be applied to the decompression surgery for lumbar spinal canal stenosis

Study Design: Thirty-four patients who were operated for spinal deformities with the Spine System Evolution (SSE) were retrospectively reviewed. Objectives: To evaluate the efficiency of SSE to correct spinal deformities. Summary of Background Data: Since the end of the Harrington rods era, several instrumentation were introduced for correction of spinal deformities. Most of these instrumentations are evolution of he CD instrumentation and are based on combination of translation, distraction/compression and possible some rotation forces. Cord injuries were informed to be more frequent with the new instruments and are related both to ischemic injuries and to mechanical insults to the cord by the supralaminar and the infralaminar hooks. Correction by the SSE is based on pedicle screws and pedicular-transverse locks. No hook is inserted into the spinal canal. Methods: All charts, radiographs, and images of the patients operated for spinal deformities with the SSE were reviewed. Thirty-four patients were found. For the purpose of this study they were evaluated for the amount of correction achieved, balance of the spine, subjective satisfaction of the cosmetic appearance and the surgical complications. Results: The mean age of the operated patients was 19.5 years. Twenty-one were operated for idiopathic scoliosis and were found to have 61% correction of the major curves. Five patients were operated for neuromuscular scoliosis with 69% of correction in average, four were operated for thoracic hyperkyphosis with reduction of the curves to physiologic range in all of them and four were operated for adult scoliosis with 38% of correction. Twenty-eight patients were satisfied from the results and the same number of patients were found to be balanced in the range of up to one-centimeter shift from the mid-line. No patient was found to have any major neurologic complication and no deep wound infections was registered. One patient had postoperative bronchopneumonia, another one had pneumothorax, one had superficial wound infection and another girl was troubled with her body image. Conclusions: SSE instrumentation was found friendly to use and relatively safe for correction of spinal deformities