CT angiography of anterior spinal artery in cervical spondylotic myelopathy

Purpose

To identify anterior spinal artery (ASA) infarct or occlusion by CT angiography (CTA) in patients with cervical spondylotic myelopathy (CSM).

Methods

Fourteen patients with CSM were performed CTA of ASA after admission. T2-weighted hyperintensity of MR image was compared with image of CTA of ASA.

Results

All patients presented spinal canal sagittal diameter compression from 10 to 80 % and different T2-weighted hyperintensity of MR images. No ASA infarct or occlusion was found in CSM patients.

Conclusion

ASA infarct or occlusion is not commonly seen in CSM patients with spinal canal sagittal diameter compression less than 80 %. Pathological changes about T2-weighted hyperintensity of MR image in CSM have no close correlation with ASA infarct.     

Measurement of volume-occupying rate of cervical spinal canal and its role in cervical spondylotic myelopathy

Purpose

To compare volume-occupying rate of cervical spinal canal between patients with cervical spondylotic myelopathy (CSM) and normal subjects, and to investigate its significance in cervical spine disease.

Methods

Spiral computed tomography (CT) scan (C4–C6 cervical spine unit) was performed in 20 normal subjects and 36 cases of CSM at a neutral position, and data were transferred to the Advantage Workstation Version 4.2 for assessment. Bony canal area and fibrous canal area in each cross section, and sagittal diameters of cervical spinal canal and cervical spinal body were measured. Volume-occupying rate of cervical spinal canal was calculated using MATLAB. Cervical spinal canal ratio and effective cervical spinal canal ratio were calculated, and Japanese Orthopaedic Association score was used to assess cervical spinal cord function.

Results

Volume-occupying rate of cervical spinal canal at a neutral position was significantly higher in CSM patients as compared to normal subjects (P < 0.01). There was no correlation between cervical spinal canal ratio and JOA score in CSM patients, with a Pearson’s correlation coefficient of 0.171 (P > 0.05). However, sagittal diameter of secondary cervical spinal canal, effective cervical spinal canal ratio and volume-occupying rate of cervical spinal canal were significantly associated to JOA score, with Pearson’s coefficient correlations of 0.439 (P < 0.05), 0.491 (P < 0.05) and ?0.613 (P < 0.01), respectively.

Conclusions

Volume-occupying rate of cervical spinal canal is an objective reflection of compression on cervical spine and spinal cord, and it is associated with cervical spinal cord function. These suggest that it may play a significant role in predicting the development of CSM.     

Driving reaction time before and after anterior cervical fusion for disc herniation: a preliminary study

Purpose

Reduced driving reaction time (DRT) has already been studied in context with lumbar disc surgeries. Data on whether cervical spine pathologies impair driving abilities are still lacking. In addition, no return-to-driving recommendations after anterior cervical fusion procedures have been published. Therefore, we assessed DRT before and after anterior cervical discectomy and fusion.

Methods

We performed a prospective study with 12 patients (mean age 47.2 years; female 7, male 5). DRT as well as arm and neck pain were evaluated before surgery, on the day before discharge from hospital and at the 4–6-week follow-up examinations. 31 healthy subjects were tested for DRT as a control group.

Results

All patients showed significant improvement in DRT in the longitudinal course (p < 0.05). DRT was 601 ms (median, IQR: 63) before surgery, which was reduced to 580 ms (median, IQR: 112) on the day before discharge from hospital and to 532 ms (median, IQR: 48) at follow-up examination. Control subjects had a driving reaction time of 487 ms (median, IQR: 116), which differed significantly from that of patients at all three testing times (p < 0.05). VAS for arm and neck pain showed significant improvement (p < 0.05).

Conclusion

The present results show a positive effect of anterior cervical discectomy and fusion on driving safety. Based on our data we state that it appears to be safe to resume driving after discharge from hospital. However, patients scheduled to undergo anterior cervical discectomy and fusion should be informed about increased DRT as compared to healthy individuals.     

Dynamic cervical myelopathy in young adults

Purpose

Non-traumatic cervical chronic joint instability in young adults is a rare and underexplored entity. We assessed the diagnostic relevance of dynamic MRI, and the clinical and radiological outcome after anterior cervical interbody fusion (ACIF) in these cases.

Methods

Six young patients (mean age 34 years) with cervical myelopathy without compression on static imaging had a dynamic MRI. Joint instability was defined by a reduction of the canal diameter on dynamic sequences. Clinical and radiological outcomes were assessed after surgery by examination, cervical X-rays, static and dynamic MRI.

Results

All the patients had joint instability. Four patients underwent surgery. Clinical status improved 1 year after surgery. All patients had a satisfactory fusion at 6-month follow-up and no residual compression at 1 year.

Conclusion

Dynamic MRI can help detect a joint instability in young patients with cervical myelopathy without compression. ACIF seems to be efficient in these cases.     

Evaluation of a new type of titanium mesh cage versus the traditional titanium mesh cage for single-level, anterior cervical corpectomy and fusion

Study design

A retrospective review of prospectively collected data in an academic institution.

Objective

To evaluate the safety and efficacy of a new type of titanium mesh cage (TMC) in single-level, anterior cervical corpectomy and fusion (ACCF).

Methods

Fifty-eight patients consecutive with cervical spondylotic myelopathy (CSM) from cervical degenerative spondylosis and isolated ossification of the posterior longitudinal ligament were treated with a single-level ACCF using either a new type of TMC (28 patients, group A) or the traditional TMC (30 patients, group B). We evaluated the patients for TMC subsidence, cervical lordosis (C2–C7 Cobb and Cobb of fused segments) and fusion status for a minimum of 30 months postoperatively based on spine radiographs. In addition, neurologic outcomes were evaluated using the Japanese Orthopedic Association (JOA) scores. Neck pain was evaluated using a 10-point visual analog scale (VAS).

Results

The loss of height of the fused segments was less for group A than for group B (0.8 ± 0.3 vs. 2.8 ± 0.4 mm) (p < 0.01); also, there was a lower rate of severe subsidence (≥3 mm) in group A (4 %, 1/28) than in group B (17 %, 5/30) (p < 0.01). There were no differences in the C2–C7 Cobb and Cobb of fused segments between the groups preoperatively or at final follow-up (p > 0.05), but the Cobb of fused segments immediately postoperative were significantly less for group B than for group A (p < 0.01). All patients, however, had successful fusion (100 %, each). Both groups had marked improvement in the JOA score after operation (p < 0.01), with no significant differences in the JOA recovery ratio (p > 0.05). The postoperative VAS neck pain scores for group A were significantly less than that for group B (p < 0.05); severe subsidence was correlated with neck pain.

Conclusions

The new type of TMC provides comparable clinical results and fusion rates with the traditional TMC for patients undergoing single-level corpectomy. The new design TMC decreases postoperative subsidence (compared to the traditional TMC); the unique design of the new type of TMC matches the vertebral endplate morphology which appears to decrease the severity of subsidence-related neck pain in follow-up.     

Comparison of titanium and polyetheretherketone (PEEK) cages in the surgical treatment of multilevel cervical spondylotic myelopathy: a prospective, randomized, control study with over 7-year follow-up

Purpose

Anterior cervical discectomy and fusion (ACDF) with titanium- or polyetheretherketone (PEEK)-cage reconstruction is widely used in the treatment of cervical spondylotic myelopathy (CSM). This study was to compare outcomes of titanium and PEEK cages in the treatment of multilevel CSM.

Methods

Between November 2002 and December 2004, a total of 80 patients with 3-level CSM were randomized in a 1:1 ratio to titanium group and PEEK group. The overall follow-up period of the patients ranged from 86 to 116 months (average 99.7 months). Clinical and radiological results were compared between titanium group and PEEK group.

Results

At the final follow-up, the clinical outcomes including JOA score, NDI score, and the excellent and good rates of clinical outcomes in the PEEK group were better than those in the titanium group. More loss of the Cobb angles and the intervertebral height was observed in the titanium group, resulting in the radiological parameters in the titanium group becoming inferior to the PEEK group at the final follow-up. Cage subsidence rates were 34.5 and 5.4 % in the titanium and PEEK groups, respectively. Fusion was observed in all patients of two groups at the final follow-up. Two patients presented with cage dislocation without clinical symptoms in the titanium group.

Conclusions

In surgical treatment of multilevel CSM, PEEK cage is superior to titanium cage in maintenance of intervertebral height and cervical lordosis, resulting in better clinical outcomes in the long-term follow-up.     

Differences between arthroplasty and anterior cervical fusion in two-level cervical degenerative disc disease

Purpose

Although arthroplasty is an accepted option for two-level disease, there is a paucity of data regarding outcomes of two-level cervical arthroplasty. The current study was designed to determine differences between two-level cervical arthroplasty and anterior fusion.

Methods

Seventy-seven consecutive patients who underwent two-level anterior cervical operations for degenerative disc disease were divided into the arthroplasty (37 patients) and fusion (40 patients) groups. Clinical outcomes were measured by Visual Analogue Scale (VAS) of neck and arm pain, Japanese Orthopedic Association (JOA) scores, and Neck Disability Index (NDI). Every patient was evaluated by radiography and computed tomography for fusion or detection of heterotopic ossification.

Results

Thirty-seven patients (with 74 levels of Bryan discs) were compared with 40 patients who had two-level anterior fusion (mean follow-up of 39.6 ± 6.7 months). There was no difference in sex, but the mean age of the arthroplasty group was significantly younger (52.1 ± 9.1 vs. 63.0 ± 10.6 years, p < 0.001). The mean estimated blood loss was similar (p = 0.135), but the mean operation time was longer in the arthroplasty group (315.5 ± 82.0 versus 224.9 ± 61.8 min, p < 0.001). At 24 months post-operation, the arthroplasty group had increased their range of motion than pre-operation (23.5° versus 20.1°, p = 0.018). There were significant improvements in neck or arm VAS, JOA scores, and NDI in both groups. However, there were no differences in clinical outcomes or adverse events between the two groups.

Conclusions

Clinical outcomes of two-level arthroplasty and anterior cervical fusion are similar 39.6 months after surgery. Cervical arthroplasty preserves mobility at the index levels without increased adverse effects.     

Results of surgical treatment of cervical spondylotic myelopathy in patients aged 75 years or more: a comparative study of operative methods

Introduction

The number of surgical procedures in elderly patients has been increasing as the population has grown older; recently, spine surgeons have been more likely to encounter elderly patients with cervical myelopathy in need of surgical treatment. There are many reports about surgical treatment of elderly patients with cervical spondylotic myelopathy (CSM); however, there are no studies about the proper selection of surgical methods and comparison of their results in CSM patients aged ≥75 years. The objective of this study was to review the results of operative methods in CSM patients aged ≥75 years.

Methods

Forty-three consecutive cases with an average age of 79 years that underwent surgical treatment were included in this study. The neurological severity was assessed using the Japanese Orthopaedic Association score for cervical myelopathy (JOA). The JOA scores were evaluated before surgery and at final follow-up. There were 21 laminoplasty procedures (from C3 to C7), 13 selective laminoplasty procedures (one above and one below the affected intervertebral level), and nine anterior decompression and fusion procedures. A selective laminoplasty was performed in cases with general complications and was diagnosed as one intervertebral level both clinically and electrophysiologically. Surgical results were compared among the three treatment groups.

Results

The average preoperative JOA score was 7.7 points and the average JOA recovery rate was 45 %. There were three cases of C5 palsy and one wound infection. Operative time and intraoperative bleeding in the selective laminoplasty group were significantly smaller than those in the other groups. There was no significant difference in the JOA recovery rates among the groups.

Conclusions

Selective laminoplasty is less invasive and the surgical results in our study were almost good. It also has good short-term results. However, the indication for surgery has to be selected carefully in elderly CSM patients.     

Long-term follow-up results of the Cloward procedure for cervical spondylotic myelopathy

Purpose

To assess the long-term results of anterior cervical discectomy and fusion using the Cloward procedure for the treatment of cervical spondylotic myelopathy, and to identify possible clinical outcome predictors.

Methods

A total of 14 cases with a 10-year postoperative follow-up were available (82.4 % of the surviving patients). Patients underwent preoperative and postoperative neurological examination. The symptom severity was graded according to the Nurick scale. MRI measurements were obtained preoperatively. Cervical spine radiographs were obtained preoperatively and at the time of follow-up.

Results

The mean improvement of the clinical status of patients on the Nurick scale was 1.43 ± 0.51 (range 1–2) with respect to the baseline values (p < 0.001), with a 62.5 % recovery rate. A positive association between the improvement of the Nurick scale and the length of follow-up was detected with an age-adjusted univariate analysis (p = 0.042). The Nurick grade improvement was also directly related to preoperative lower limb hyperreflexia (p = 0.039), spasticity (p = 0.017), and bladder dysfunction (p = 0.048). At the time of follow-up, an adjacent discopathy was noted above and below the operated level(s) in eight and six patients, respectively.

Conclusions

The Cloward technique is a safe and effective procedure for the treatment of cervical spondylotic myelopathy. The patients’ preoperative neurological status and the length of follow-up affect the grade of postoperative ambulatory improvement.     

Reduction in range of cervical motion on serial long-term follow-up in patients undergoing oblique corpectomy for cervical spondylotic myelopathy

Purpose

To determine whether motion preservation following oblique cervical corpectomy (OCC) for cervical spondylotic myelopathy (CSM) persists with serial follow-up.

Methods

We included 28 patients with preoperative and at least two serial follow-up neutral and dynamic cervical spine radiographs who underwent OCC for CSM. Patients with an ossified posterior longitudinal ligament (OPLL) were excluded. Changes in sagittal curvature, segmental and whole spine range of motion (ROM) were measured. Nathan’s system graded anterior osteophyte formation. Neurological function was measured by Nurick’s grade and modified Japanese Orthopedic Association (JOA) scores.

Results

The majority (23 patients) had a single or 2-level corpectomy. The average duration of follow-up was 45 months. The Nurick’s grade and the JOA scores showed statistically significant improvements after surgery (p < 0.001). 17 % of patients with preoperative lordotic spines had a loss of lordosis at last follow-up, but with no clinical worsening. 77 % of the whole spine ROM and 62 % of segmental ROM was preserved at last follow-up. The whole spine and segmental ROM decreased by 11.2° and 10.9°, respectively (p ≤ 0.001). Patients with a greater range of segmental movement preoperatively had a statistically greater range of movement at follow-up. The analysis of serial radiographs indicated that the range of movement of the whole spine and the range of movement at the segmental spine levels significantly reduced during the follow-up period. Nathan’s grade showed increase in osteophytosis in more than two-thirds of the patients (p ≤ 0.01). The whole spine range of movement at follow-up significantly correlated with Nathan’s grade.

Conclusions

Although the OCC preserves segmental and whole spine ROM, serial measurements show a progressive decrease in ROM albeit without clinical worsening. The reduction in this ROM is probably related to degenerative ossification of spinal ligaments.     

Documentation of outcomes for sacroiliac joint fusion: does prior spinal fusion influence the outcome?

Purpose

The purpose of this prospective case series (level II) was to determine the clinical outcomes of anterior SIJ fusion, comparing the outcomes of patients who had prior spinal fusions at any level compared to patients who have not.

Methods

This prospective study included 25 patients who underwent SIJ fusion with anterior plate fixation. All patients had failed non-operative treatment, had a positive Patrick test, and positive response to intra-articular SIJ injections with greater than 50 % pain relief. Patients had follow-up at 3, 6, 9 and 12 months where they completed Oswestry disability index (ODI) and Short Musculoskeletal Functional Assessment (SMFA) surveys. Outcome data are available for 19 patients who completed pre-operative and 12-month follow-up surveys. Their average time of the final follow-up was 1.1 years (range 10–33 months).

Results

Significant improvements between pre-operative and the final follow-up in ODI (p = 0.007) and SMFA (p = 0.01) were observed; the ODI assessed outcomes in patients who had previous spinal fusion surgery were significantly worse than those that did not at the final follow-up (p = 0.04).

Conclusion

Patients who have not undergone prior spinal fusion surgery, regardless of age, gender, and BMI have better outcomes following anterior SIJ fusion.     

Segmental anterior cervical corpectomy and fusion with preservation of middle vertebrae in the surgical management of 4-level cervical spondylotic myelopathy

Purpose

To compare perioperative parameters, clinical outcomes, radiographic parameters, and complication rates of segmental anterior cervical corpectomy and fusion (sACCF) plus preservation of middle vertebrae with those of cervical laminectomy plus fusion (CLF) in 67 patients with 4-level cervical spondylotic myelopathy (CSM).

Methods

Between July 2006 and May 2012, 67 consecutive patients [42 males and 25 females; mean age 57.8 years (range 34–77 years)] with 4-level CSM who underwent surgery and were followed for more than 1 year were enrolled in this study and divided into sACCF and CLF groups. The study compared perioperative parameters; surgery-related and instrumentation- and graft-related complication rates; clinical parameters; patient satisfaction; and radiologic parameters.

Results

Significant improvements were seen from preoperative to postoperative in both groups for all three measures of clinical outcome; between-group comparison revealed no significant difference for two of the three measures and significantly better scores for the CLF group in the third. Satisfaction was rated as excellent or good by 79.5 % of the sACCF group and 71.4 % of the CLF group, which was not a significant difference. Mean postoperative cervical lordosis was significantly greater in the sACCF group than in the CLF group. Blood loss and operative time were significantly greater in the CLF group than in the sACCF group and complication rate significantly lower for the sACCF group.

Conclusions

sACCF with preservation of middle vertebrae is a safe, reliable, and effective alternative procedure for the treatment of 4-level CSM.     

Long-term surgical outcomes of cervical myelopathy with athetoid cerebral palsy

Purpose

To understand the long-term surgical outcomes and prognostic factors for the operative treatment of cervical myelopathy (CM) in patients with athetoid cerebral palsy (ACP).

Methods

We retrospectively reviewed 24 patients with ACP who underwent surgery for CM at our hospital between March 2002 and June 2008. All patients had more than 5 years follow-up. Anterior fusion (11 patients), posterior fusion (1 patient), or combined anterior and posterior (AP) fusion (7 patients) and C1-2 fusion (5 patients) surgeries were performed. Surgical outcomes (average follow-up 102 months), as assessed using modified JOA (mJOA) scores, the Neck Disability Index (NDI), and a visual analog scale (VAS) were compared between the preoperative and postoperative states.

Results

Preoperatvie cervical kyphosis decreased mJOA scores significantly. Long-term follow-up clinical outcomes demonstrated that 10 patients showed favorable (excellent and good) outcomes and 11 patients had non-favorable (fair and worse) outcomes. According to the mJOA scores, patients showed postoperative improvement (7.10–10.45). NDI decreased from 68.46 to 31.66. A second operation was done in seven cases due to instrument failure, progressive kyphotic deformities and adjacent segment degeneration. A preoperative botulinum toxin injection significantly decreased (p < 0.05) the incidence of a second operation.

Conclusions

Patients with ACP have high incidence of instrument failure. Strong surgical fixation, bone fusion and perioperative immobilizations using botulinum toxin injection should be carefully planned preoperatively.     

Early neurological recovery course after surgical treatment of cervical spondylotic myelopathy: a prospective study with 2-year follow-up using three different functional assessment tests

Purpose

Though surgical decompression is today a common option for treatment of cervical spondylotic myelopathy (CSM), little is known about the exact postoperative early neurological recovery course. The purpose of this study was to analyze the functional recovery, its dynamics, its intensity and its pattern, in the early postoperative period after surgical decompression for CSM.

Methods

A prospective non-controlled observational study was performed from March 2006 to July 2008, and included consecutive patients with CSM who underwent surgical decompression. Functional assessments were done before the operation, at 1 month, 6, 12, 18 and 24 months after surgery using three tests: the Japanese Orthopaedic Association (JOA) test, the nine-hole peg test (9HPT) and the Crockard walking test.

Results

Sixty-seven patients were included (mean age of 61 years). The global JOA score improved after surgery, reaching statistical significance at 1 month (from 11.5 ± 2.6 to 13.6 ± 2.0 points, p = 0.0078), then settling to a plateau till the end of follow-up at 24 months (12.7 ± 2.6 points). The 9HPT and the Crockard test did not show any significant improvement after surgery.

Conclusions

Neurological recovery after surgical decompression has been proved to be very fast during the first month, but stabilizes afterwards. The JOA score is the best assessment to reveal neurological improvement in the early recovery course.     

Anterior corpectomy and fusion to C2 for cervical myelopathy: clinical results and complications

Purpose

Anterior cervical corpectomy and fusion (ACCF) to C2 (ACCF-C2) for multilevel lesions is a challenging procedure that is indicated for massive ossification of the posterior longitudinal ligament (OPLL) extending to C2 or stenosis at the upper cervical region accompanied by kyphosis. However, there is little information on the effectiveness of and complications related to ACCF-C2. The purpose of this study was to investigate the overall surgical results and postoperative complications of ACCF-C2 for cervical myelopathy.

Methods

Sixteen patients who underwent ACCF-C2 for OPLL and cervical spondylotic myelopathy were evaluated. An iliac bone or a fibular strut was grafted using a cervical plate. The mean fusion level was 3.8, and the mean follow-up period was 36 months. Patients’ charts, clinical results assessed using the Japanese Orthopedic Association (JOA) scale, and radiographs were retrospectively reviewed.

Results

The average preoperative JOA score was 11.5 ± 3.5, and improved significantly to 13.1 ± 3.2 at 24 months after surgery (P < 0.01). The postoperative cervical alignment was significantly improved at the last follow-up (P < 0.05). Seven patients experienced complications, including neurological complications in three, graft-related complications in three, cerebrospinal fluid leakage in two, late retropharyngeal perforation in one, and dysphasia in one. Three of 16 patients experienced upper airway obstruction in this series, and 2 of 473 patients who underwent anterior cervical decompression and fusion at lower levels in the same period (P < 0.001).

Conclusions

ACCF-C2 is effective for massive OPLL and stenosis accompanied by kyphosis. To avoid complications, skilled decompression and bone grafting technique are necessary, and delayed extubation for upper airway obstruction is preferable.     

Favourable outcome of posterior decompression and stabilization in lordosis for cervical spondylotic myelopathy: the spinal cord “back shift” concept

Purpose

Surgical management of patients with multilevel CSM aims to decompress the spinal cord and restore the normal sagittal alignment. The literature lacks of high level evidences about the best surgical approach. Posterior decompression and stabilization in lordosis allows spinal cord back shift, leading to indirect decompression of the anterior spinal cord. The purpose of this study was to investigate the efficacy of posterior decompression and stabilization in lordosis for multilevel CSM.

Methods

36 out of 40 patients were clinically assessed at a mean follow-up of 5, 7 years. Outcome measures included EMS, mJOA Score, NDI and SF-12. Patients were asked whether surgery met their expectations and if they would undergo the same surgery again. Bone graft fusion, instrumental failure and cervical curvature were evaluated. Spinal cord back shift was measured and correlation with EMS and mJOA score recovery rate was analyzed.

Results

All scores showed a significative improvement (p < 0.001), except the SF12-MCS (p > 0.05). Ninety percent of patients would undergo the same surgery again. There was no deterioration of the cervical alignment, posterior grafted bones had completely fused and there were no instrument failures. The mean spinal cord back shift was 3.9 mm (range 2.5–4.5 mm). EMS and mJOA recovery rates were significantly correlated with the postoperative posterior cord migration (P < 0.05).

Conclusions

Posterior decompression and stabilization in lordosis is a valuable procedure for patients affected by multilevel CSM, leading to significant clinical improvement thanks to the spinal cord back shift. Postoperative lordotic alignment of the cervical spine is a key factor for successful treatment.

     

Cervical curvature, spinal cord MRIT2 signal, and occupying ratio impact surgical approach selection in patients with ossification of the posterior longitudinal ligament

Objective

Factors impacting surgical options and outcomes in patients with cervical ossification of the posterior longitudinal ligament (OPLL) were explored.

Methods

A retrospective analysis was conducted of 127 eligible cervical OPLL patients (61 males, 66 females) aged 41–70 years (mean 55.2 years) selected from 152 total OPLL patients treated from 2002 to 2006, with 5–10-year (mean 6.8 years) follow-up. Patients underwent anterior subtotal corpectomy with ossification ligament resection (anterior surgery, n = 68) or posterior cervical double-door laminoplasty (posterior surgery, n = 59). Radiographic assessments of cervical curvature, T2-weighted MRI (MRIT2) signal, and OPLL occupying ratio were correlated with surgical strategy before surgery and at 1, 5 weeks, and 5 years.

Results

Lordosis increased following anterior surgery, though kyphosis improved by 10.3 %. The canal stenosis occupying ratio was >50 %, and short-term improvement following anterior surgery was significantly higher than posterior surgery (P > 0.0001). Superior neurological function was observed in patients with unchanged versus high spinal MRIT2 signals (P = 0.0434). No significant differences were observed in short-term outcomes between anterior and posterior surgeries in high spinal MRIT2 signal patients, but anterior surgery produced significantly better long-term outcomes at 1 week (P = 0.7564) and 1 year (P = 0.0071). Complications occurred in five anterior and three posterior surgeries.

Conclusion

Preoperative assessment of cervical curvature, MRIT2 signal, and occupying ratio can be used to guide clinical surgical approach selection to potentially produce better long-term outcomes in patients with OPLL.     

Can cantilever transforaminal lumbar interbody fusion (C-TLIF) maintain segmental lordosis for degenerative spondylolisthesis on a long-term basis?

Purpose

To determine if cantilever transforaminal lumbar interbody fusion (C-TLIF) using the crescent-shaped titanium interbody spacer (IBS) favors acquisition of segmental and lumbar lordosis even for degenerative spondylolisthesis (DS) on a long-term basis.

Methods

We analyzed 23 consecutive patients who underwent C-TLIF with pedicle screw instrumentations fixed with compression for a single-level DS. Measurements on the lateral radiographs taken preoperatively, 2 weeks postoperatively and at final follow-up included disc angle (DA), segmental angle (SA), lumbar lordosis (LL), disc height (%DH) and slip rate (%slip).

Results

There was a good functional recovery with 100 % fusion rate at the mean follow-up of 62 months. Segmental lordosis (DA and SA) and  %DH initially increased, but subsequently decreased with the subsidence of the interbody spacer, resulting in a significant increase (p = 0.046) only in SA from 13.2° ± 5.5° preoperatively to 14.7° ± 6.4° at the final follow-up. Changes of LL and  %slip were more consistent without correction loss finally showing an increase of LL by 3.6° (p = 0.005) and a slip reduction by 6.7 % (p < 0.001).

Conclusions

Despite the inherent limitation of placing the IBS against the anterior endplate of the upper vertebra in the presence of DS, the C-TLIF helped significantly restore segmental as well as lumbar lordosis on a long-term basis, which would be of benefit in preventing hypolordosis-induced back pain and the adjacent level disc disease.     

Treatment of basilar invagination

Purpose

Basilar invagination is a rare craniocervical malformation which may lead to neurological deficits related to compression of brainstem and upper cervical cord as well as instability of the craniocervical junction. This study presents results of a treatment algorithm developed over a 20-year period focussing on anatomical findings, short-term and long-term outcomes.

Methods

69 patients with basilar invagination (mean age 41 ± 18 years, history 64 ± 85 months) were encountered. The clinical courses were documented with a score system for individual neurological symptoms for short-term results after 3 and 12 months. Long-term outcomes were analyzed with Kaplan–Meier statistics.

Results

Patients with (n = 31) or without (n = 38) ventral compression were distinguished. 25 patients declined an operation, while 44 patients underwent 48 operations. Surgical management depended on the presence of ventral compression and segmentation anomalies between occiput and C3, signs of instability and presence of caudal cranial nerve dysfunctions. 16 patients without ventral compression underwent foramen magnum decompressions without fusion. 19 patients with ventral compression and abnormalities of segmentation or evidence of instability underwent a foramen magnum decompression with craniocervical (n = 18) or C1/2 (n = 1) stabilization. In nine patients with severe ventral compression and caudal cranial nerve deficits, a transoral resection of the odontoid was combined with a posterior decompression and fusion. Within the first postoperative year neurological scores improved for all symptoms in each patient group. In the long-term, postoperative deteriorations were related exclusively to instabilities either becoming manifest after a foramen magnum decompression in three or as a result of hardware failures in two patients.

Conclusions

The great majority of patients with basilar invagination report postoperative improvements with this management algorithm. Most patients without ventral compression can be managed by foramen magnum decompression alone. The majority of patients with ventral compression can be treated by posterior decompression, realignment and stabilization alone, reserving anterior decompressions for patients with profound, symptomatic brainstem compression.     

Expandable titanium cages for anterior column cervical reconstruction and their effect on sagittal profile: a review of 48 cases

Background

Expandable cervical cages have been utilised successfully to reconstruct the cervical spine for various conditions. However, to date there are only limited data on their influence on cervical sagittal profile. In this retrospective study, we present our experience with performing anterior cervical corpectomy in one or two levels using expandable titanium cages in order to achieve stable reconstruction and restoration of cervical lordosis.

Methods

A case series of data from 48 consecutive patients (20 men, 28 women; mean age 61 years) operated upon in a 5-year-period is retrospectively reviewed. Standard anterior single- or two-level cervical corpectomy, fusion and spinal reconstruction were performed, including placement of an expandable titanium cage and an anterior cervical plate. The mean follow-up was 23 months (range, 8–42 months). Outcome was measured by clinical examinations and visual analogue scale (VAS) scale; myelopathy was classified according the Nurick grading system. Radiographic analysis comprised several parameters, including segmental Cobb angle, cervical lordosis, subsidence ratio and sagittal cage angle. Computed tomography was done 1 and 2 years after surgery; cervical spine radiographs were obtained 3, 6, 12 and 24 months after surgery.

Results

In 38 patients (79 %) osseous fusion or stability of construct could be demonstrated in the 2-year follow up examination. The mean restoration of segmental Cobb angle as well as cervical lordosis amounted to 7.6° and 5.4° respectively, both being statistically significant. Furthermore, a profound correction (10° or more) of the sagittal cervical curve was shown in 15 patients.

Conclusion

Regarding the restoration of the physiological sagittal cervical profile, expandable cervical cages seem to be efficient and easy to use for cervical spine reconstruction after anterior corpectomy. Donor-site-related complications are avoided, fast and strong reconstruction of the anterior column is provided, resulting in satisfactory fusion rates after 2 years.