A retrospective comparative study.
To provide an ideal correction angle of lumbar lordosis (LL) in degenerative flat back deformity.
Overview of Literature
The degree of correction in degenerative flat back in relation to pelvic incidence (PI) remains controversial.
Forty-nine patients with flat back deformity who underwent corrective surgery were enrolled. Posterior-anterior-posterior sequential operation was performed. Mean age and mean follow-up period was 65.6 years and 24.2 months, respectively. We divided the patients into two groups based on immediate postoperative radiographs-optimal correction (OC) group (PI-9°≤LL
Patients in OC group had significantly less correction loss and maintained normal sagittal alignment (sagittal vertical axis<5 cm), as compared to patients in UC group (p<0.05). LL of low PI group significantly maintained within 9° better than high PI group (p<0.05). Oswestry disability index (ODI) significantly decreased at last follow-up, as compared to preoperative state. However, there was no significant difference in last follow-up ODI between the groups.
In flat back deformity, correction of LL to within 9° of PI will result in better sagittal balance. Thus, we recommend sufficient LL to prevent correction loss, especially in patients with high PI.
Flat back deformity; Lumbar lordosis; Pelvic incidence
To evaluate the radiological and clinical results of three different methods in the deformity correction of a degenerative flat back.
Overview of Literature
There are no comparative studies about different procedures in the treatment of degenerative flat back.
Sixty-four patients who consecutively underwent corrective surgery for degenerative flat back were reviewed. The operations were performed by three different methods: posterior-only (group P, n=20), one-stage anterior-posterior (group AP, n=12), and two-stage anterior-posterior with iliac screw fixation (group AP-I, n=32). Medical and surgical complications were examined and radiological and clinical results were compared.
The majority of medical and surgical complications were found in group AP (5/12) and group P (7/20). The sagittal vertical axes were within normal range immediately postoperatively in all groups, but only group AP-I showed normal sagittal alignment at the final follow-up. Postoperative lumbar lordosis was also significantly higher in group AP-I than in group P or group AP and the finding did not change through the last follow-up. The Oswestry disability index was significantly lower in groups AP and AP-I than in group P at the final follow-up. Meanwhile, the operating time was the longest in group AP-I, and total amount of blood loss was larger in group AP-I and group AP than in group P.
Anterior-posterior correction showed better clinical results than posterior-only correction. Two-staged anterior-posterior correction with iliac screw fixation showed better radiological results than posterior-only or one-staged anterior-posterior correction. Two-staged anterior-posterior correction with iliac screw fixation also showed a lower complication rate than one-staged anterior-posterior correction.
Lumbar vertebrae; Kyphosis; Surgical procedures; Treatment outcome
Epidural injection of hyaluronic acid may prevent adhesion formation after spine surgery, but the compounds used to stabilize hyaluronidase could interfere with its anti-adhesion effects. The present study was conducted as a clinical trial to evaluate the efficacy and safety of an experimental medical gel in preventing adhesion formation.
This study was designed as a multicenter, randomized, double-blind, and comparative controlled clinical trial with an observation period of 6 weeks. Subjects were randomly assigned into two groups: group A with sodium hyaluronate + 1,4-butanediol diglycidyl ether (BDDE) and group B with sodium hyaluronate + sodium carboxymethylcellulose (CMC). Visual analogue scale (VAS) of back and leg pain and the Oswestry disability index (ODI) and scar score ratings were assessed after surgery.
Mean scar grade was 2.37±1.13 in group A and 2.75±0.97 in group B, a statistically significant difference (p=0.012). VAS of back and leg pain and ODI scores decreased significantly from baseline to 3 and 6 weeks postoperatively in both groups (p<0.001). However, VAS and ODI scores were not statistically different between groups A and B at baseline or at 3 and 6 weeks after operation (p>0.3). The number of adverse reactions related to the anti-adhesion gels was not statistically different (p=0.569), but subsequent analysis of nervous adverse reactions showed group B was superior with a statistically difference (p=0.027).
Sodium hyaluronate with BDDE demonstrated similar anti-adhesion properties to sodium hyaluronate with CMC. But, care should be used to nervous adverse reactions by using sodium hyaluronate with BDDE.
Anti-adhesion; Scar formation; Lumbar discectomy; Sodium hyaluronate; 1,4-butanediol diglycidyl ether (BDDE); Sodium carboxymethylcellulose (CMC)
To investigate influence of bone mineral density (BMD) on the surgical correction of lumbar degenerative kyphosis (LDK).
Overview of Literature
No studies so far have reported the influence of BMD on the surgical correction of LDK.
Forty LDK patients with more than 2 years follow-up were studied. Pelvic incidence (PI), pelvic tilt, sacral slope, sagittal vertical axis (SVA), lumbar lordosis (LL), and thoracic kyphosis were measured preoperatively, immediate postoperatively and at final follow-up. Adverse outcomes: proximal adjacent fractures, sagittal decompensation, pseudoarthrosis, and cage subsidence were documented.
There were 37 females and 3 males. Average age was 65.1±4.5 years and mean follow-up was 34.2±16.7 months. 42.5% were Takemitsu type 3 curves, 27.5% type 2, 20.0% type 4 and 10.0% type 1. 37.5% had osteopenia, 40.0% osteoporosis and 22.5% had severe osteoporosis. SVA improved from 237.0±96.7 mm preoperatively to 45.3±41.8 mm postoperatively (p=0.000). LL improved from 10.5°±14.7° to -40.6°±10.9° postoperatively (p=0.000). At final follow-up SVA deteriorated to 89.8±72.2 mm and LL to 34.7°±15.8° (p=0.000). The association between late sagittal decompensation, pseudoarthrosis, or proximal adjacent fractures and osteoporosis was insignificant. The difference between immediate postoperative LL and PI (PIDiff) had a significant association with sagittal decompensation and pseudoarthrosis.
Osteoporosis did not influence the degree of correction, late sagittal decompensation, proximal adjacent fractures, and pseudoarthrosis in LDK. PIDiff had a significant association with sagittal decompensation and pseudoarthrosis.
Lumbar degenerative kyphosis; Bone mineral density; Surgery; Outcome; Osteoporosis
To determine whether ACE insertion/deletion (I/D) polymorphism is associated with the ossification of the posterior longitudinal ligament (OPLL) of the spine in the Korean population.
A case-control study was conducted to investigate the association between I/D polymorphism of the angiotensin I converting enzyme (peptidyl-dipeptidase A) 1 (ACE) gene and OPLL. The 95 OPLL patients and 274 control subjects were recruited. Polymerase chain reaction for the genotyping of ACE I/D polymorphism was performed. The difference between the OPLL patients and the control subjects was compared using the contingency χ2 test and the logistic regression analysis. For statistical analysis, SPSS, SNPStats, SNPAnalyzer, and Helixtree programs were used.
The genotype and allele frequencies of ACE I/D polymorphism showed significant differences between the OPLL patients and the control subjects (genotype, p<0.001; allele, p=0.009). The frequencies of D/D genotype and D allele in the OPLL group were higher than those in the control group. In logistic regression analysis, ACE I/D polymorphism was associated with OPLL (dominant model; p=0.002; odd ratio, 2.20; 95% confidence interval, 1.33-3.65).
These results suggest that the deletion polymorphism of the ACE gene may be a risk factor for the development of OPLL in the Korean population.
Ossification of the posterior longitudinal ligament; Angiotension converting enzyme; Genetic polymorphism; Genetic association analysis
Degenerative lumbar scoliosis (DLS) is a spinal deformity that develops after skeletal maturity and progresses with age. In contrast to adolescent idiopathic scoliosis, the genetic association of DLS has not yet been elucidated. The purpose of this study was to investigate the association between regulating synaptic membrane exocytosis 2 (RIMS2, OBOE) gene polymorphisms and DLS. Two coding single-nucleotide polymorphisms [rs2028945 (Gln1200Gln) and rs10461 (Ala1327Ala)] of RIMS2 were selected and genotyped by direct sequencing. As a result, the rs10461 was associated with DLS in allele frequencies (P=0.008) and genotype distributions (P=0.006 in the codominant model, 0.018 in the dominant model and 0.029 in the recessive model). In the analysis of haplotypes, two haplotypes exhibited significant differences between the control and DLS groups (CC haplotype, P=0.009 in the codominant model, 0.038 in the dominant model and 0.030 in the recessive model; CT haplotype, P=0.041 in the codominant model and 0.021 in the dominant model). These findings suggest that RIMS2 may be associated with the development of DLS.
degenerative lumbar scoliosis; regulating synaptic membrane exocytosis 2; polymorphism
Degenerative lumbar scoliosis (DLS) progresses with aging after 50–60 years. The genetic association of DLS remains largely unclear. In this study, the genetic association between glutamate receptor, ionotropic, N-methyl D-aspartate (NMDA, GRIN) receptor genes and DLS was investigated. A total of 9 coding single nucleotide polymorphisms (cSNPs) in NMDA receptor genes [GRIN2A (rs8049651, Leu425Leu; rs9806806, Tyr730Tyr); GRIN2B (rs7301328, Pro122Pro; rs35025065, Asp447Asp; rs1805522, Ile602Ile; rs1806201, Thr888Thr; rs1805247, His1399His); and GRIN2C (rs689730, Ala33Ala; rs3744215, Arg1209Ser)] were selected and genotyped using direct sequencing in 70 patients with DLS and 141 healthy controls. Multiple logistic models (codominant, dominant and recessive) were calculated for the odds ratio (OR), 95% confidence interval (CI) and corresponding P-values. The SNPStats, SNPAnalyzer and HelixTree programs were used for the evaluation of the genetic data. Among the SNPs examined, no significant associations were observed between the NMDA receptor genes and DLS. When the patients were divided into two groups according to clinical characteristics based on Cobb’s angle (<20° or ≥20°) and lateral listhesis (<6 mm or ≥6 mm), associations were observed between rs689730 of GRIN2C and Cobb’s angle (codominant, P=0.038; dominant, P=0.022) and between rs7301328 of GRIN2B and lateral listhesis (codominant, P=0.003; dominant, P=0.015; recessive, P=0.015). These results indicate that the GRIN2A, GRIN2B and GRIN2C genes do not affect the development of DLS. However, the GRIN2C gene may be associated with Cobb’s angle, while the GRIN2B gene may be associated with lateral listhesis.
GRIN2; single nucleotide polymorphism; degenerative lumbar scoliosis; Korean
To present the accuracy and safety of cervical pedicle screw insertion using the technique with direct exposure of the pedicle by laminoforaminotomy.
We retrospectively reviewed 12 consecutive patients. A total of 104 subaxial cervical pedicle screws in 12 patients had been inserted. We also assessed the clinical and radiological outcomes and analyzed the direction and grade of pedicle perforation (grade 0: no perforation, 1: <25%, 2: 20% to 50%, 3: >50% of screw diameter) on the postoperative vascular-enhanced computed tomography scans. Grade 2 and 3 were considered as incorrect position.
The correct position was found in 95 screws (91.3%); grade 0-75 screws, grade 1-20 screws and the incorrect position in 9 screws (8.7%); grade 2-6 screws, grade 3-3 screws. There was no neurovascular complication related with cervical pedicle screw insertion.
This technique (technique with direct exposure of the pedicle by laminoforaminotomy) could be considered relatively safe and easy method to insert cervical pedicle screw.
Cervical pedicle screw; Laminoforaminotomy; Pedicle perforation
The prevalence of intervertebral disc herniation (IDH) of the thoracic spine is rare compared to the cervical or lumbar spine. In particular, IDH of the upper thoracic spine is extremely rare. We report the case of T1-2 IDH and its treatment, with a literature review. A 37-year-old male patient visited our hospital due to radiating pain at the left upper extremity and weakness of grip power. In cervical spine magnetic resonance images, T1-2 disc space showed herniated disc material and compressed T1 root was identified. Laminoforaminotomy was performed with a posterior approach. The radiating pain and weakness of grip power improved immediately after the surgery. Of patients who show radiating pain or numbness at the medial aspect of forearm, or weakness of intrinsic muscle of hand, can be suspected to have T1 radiculopathy. A detailed physical examination and a radiologic evaluation including this area should be required for the T1 radiculopathy.
Thoracic Vertebrae; Intervertebral Disc; Radiculopathy; Laminotomy
We performed L1 posterior vertebral columnar resection and posterior correction for Andersson's lesion and thoracolumbar kyphosis in an ankylosing spondylitis patient during motor evoked potential (MEP) monitoring. We checked MEP intra-operatively, whenever a dangerous procedure for neural elements was performed, and no abnormal findings were seen during surgery. After the operation, we examined neurologic function in the recovery room; the patient showed a progressive neurologic deficit and no response to MEP. After emergency neural exploration and decompression surgery, the neurologic deficit was recovered. We questioned whether to acknowledge the results of this case as a false negative. We think the possible reason for this result may be delayed development of paralysis. So, we recommend that MEP monitoring should be performed not only after important operative steps but also after all steps, including skin suturing, for final confirmation.
Spine operation; Deformity correction; Motor evoked potential; Delayed paraplegia
The aim of this study was to determine whether anterior column support is required in Smith-Petersen osteotomy procedure with correction angles of more than 10°, while examining the subsequent healing patterns in relation to the disrupted area.
An analysis was done on 26 segments of 19 patients who showed a correction angle of more than 10° in the anterior opening after SPO. There were 17 male and two female patients with a mean age of 40 years (24–56 years). The mean follow-up period was 6.5 years (2–9.1 years). The patients were classified according to the site of the anterior opening, as the disc level, the lower end-plate of the upper body (upper body), or the upper end-plate of the lower body (lower body). The healing patterns of anterior opening and the radiological correction angles were evaluated relative to the opening site.
In all cases, bony fusion was confirmed at a mean period of 5.6 months (3–6.7 months) after surgery and the anterior opening gap was healed in 18 segments (69.2%). For patients that developed an opening in the upper body, all of the gaps were healed. The gaps in the lower body opening group were healed in 85.7% of the cases, and for the opening at the disc level, the gaps were healed only in 12.5% of the cases. The least amount of correction was obtained when anterior opening occurred in disc level.
In our study of subjects presenting with anterior opening angles from 10° to 32°, we obtained successful fusion without the need for additional anterior interbody fusion. Improved gap healing and increased correction angles were obtained when the opening was present in the upper or lower body endplates compared to those at the disc space level.
Ankylosing spondylitis; Kyphotic deformity; Smith-Petersen osteotomy
To evaluate the clinical and radiological outcomes of lumbar interbody fusion and its correlation with various factors (e.g., age, comorbidities, fusion level, bone quality) in patients over and under 65 years of age who underwent lumbar fusion surgery for degenerative lumbar disease.
One-hundred-thirty-three patients with lumbar degenerative disease underwent lumbar fusion surgery between June 2006 and June 2007 and were followed for more than one year. Forty-eight (36.1%) were older than 65 years of age (group A) and 85 (63.9%) were under 65 years of age (group B). Diagnosis, comorbidities, length of hospital stay, and perioperative complications were recorded. The analysis of clinical outcomes was based on the visual analogue scale (VAS). Radiological results were evaluated using plain radiographs. Clinical outcomes, radiological outcomes, length of hospital stay, and complication rates were analyzed in relation to lumbar fusion level, the number of comorbidities, bone mineral density (BMD), and age.
The mean age of the patients was 61.2 years (range, 33-86 years) and the mean BMD was -2.2 (range, -4.8 to -2.8). The mean length of hospital stay was 15.0 days (range, 5-60 days) and the mean follow-up was 23.0 months (range, 18-30 months). Eighty-five (64.0%) patients had more than one preoperative comorbidities. Perioperative complications occurred in 27 of 133 patients (20.3%). The incidence of overall complication was 22.9% in group A, and 18.8% in group B but there was no statistical difference between the two groups. The mean VAS scores for the back and leg were significantly decreased in both groups (p < 0.05), and bony fusion was achieved in 125 of 133 patients (94.0%). There was no significant difference in bony union rates between groups A and B (91.7% in group A vs. 95.3% in group B, p = 0.398). In group A, perioperative complications were more common with the increase in fusion level (p = 0.027). Perioperative complications in both groups A (p = 0.035) and B (p = 0.044) increased with an increasing number of comorbidities.
Elderly patients with comorbidities are at a high risk for complications and adverse outcomes after lumbar spine surgery. In our study, clinical outcomes, fusion rates, and perioperative complication rates in older patients were comparable with those in younger populations. The number of comorbidities and the extent of fusion level were significant factors in predicting the occurrence of postoperative complications. However, proper perioperative general supportive care with a thorough fusion strategy during the operation could improve the overall postoperative outcomes in lumbar fusion surgery for elderly patients.
Elderly patients; Lumbar interbody fusion; Comorbidities; Complications
The management of lower cervical fractures in patients with ankylosing spondylitis (AS) differs from normal cervical fractures. Patients with AS are highly susceptible to extensive neurologic injuries and spinal deformities after cervical fractures from even minor traumatic forces. These injuries are uniquely complex, require careful imaging assessment, and aggressive surgical management to optimize spinal stability and functional outcomes.
Ankylosing spondylitis; Lower cervical spine fracture
The purpose of this study was to analyze the biomechanical effects of three different constrained types of an artificial disc on the
implanted and adjacent segments in the lumbar spine using a finite element model (FEM).
The created intact model was validated by comparing the flexion-extension response without pre-load with the corresponding results obtained from the published experimental studies. The validated intact lumbar model was tested after implantation of three artificial discs at L4-5. Each implanted model was subjected to a combination of 400 N follower load and 5 Nm of flexion/extension moments. ABAQUS™ version 6.5 (ABAQUS Inc., Providence, RI, USA) and FEMAP version 8.20 (Electronic Data Systems Corp., Plano, TX, USA) were used for meshing and analysis of geometry of the intact and implanted models.
Under the flexion load, the intersegmental rotation angles of all the implanted models were similar to that of the intact model, but under the extension load, the values were greater than that of the intact model. The facet contact loads of three implanted models were greater than the loads observed with the intact model.
Under the flexion load, three types of the implanted model at the L4-5 level showed the intersegmental rotation angle similar to the one measured with the intact model. Under the extension load, all of the artificial disc implanted models demonstrated an increased extension rotational angle at the operated level (L4-5), resulting in an increase under the facet contact load when compared with the adjacent segments. The increased facet load may lead to facet degeneration.
Artificial disc; Lumbar spine; Finite element model; Rotation angle; Facet contact load; von-Mises stress
There are a number of reports on Smith-Petersen osteotomy (SPO), pedicle subtraction osteotomy (PSO) and vertebral column resection (VCR). However, there are few systematic reviews of all three kinds of osteotomies. Literature review and author's experience of SPO, PSO and VCR osteotomy will be described. Various surgical techniques can be applied according to the disease entity and magnitude of the deformity. The most appropriate methods for deformity correction should be chosen and the potential complications should be considered. Before attempting an osteotomy of the spine for a spinal deformity, sufficient surgical experience and a thorough understanding of the anatomy of the spine and adjacent structures are needed. In addition, a well-organized team with the other departments is essential.
Spinal osteotomy; Smith-Petersen osteotomy; Pedicle subtraction osteotomy; Vertebral column resection
Nontraumatic intracranial subarachnoid hemorrhage (SAH) attributable to the thoracolumbar dural arteriovenous fistulas (DAVFs) has been extremely rare. A 41-year-old male patient was admitted with severe acute headache, neck stiffness, and pronounced low-back pain radiating to both legs. The T2-weighted MR imaging showed irregular signal void and enlarged, varix like pouch formation with spinal cord compression at the T11-12 level. The angiogram revealed a DAVF.
We report a DAVF case with SAH that revealed an extensive infarction from C5 to the conus medullaris after undergoing operative treatment.
Dural arteriovenous fistula; Subarachnoid hemorrhage; Spinal cord infarction
This study was designed to reevaluate the effectiveness of the Pavlov ratio in patients with cervical myelopathy.
We studied 107 patients who underwent open door laminoplasty for the treatment of cervical myelopathy between the C3 to C7 levels. We determined the Pavlov ratio on preoperative and postoperative cervical spine lateral radiographs, the vertebral body-to-canal ratio on sagittal reconstruction CT scans, and the vertebral body-to-cerebrospinal fluid (CSF) column ratio on T2-weighted sagittal MR images from C3 to C6. The severity of myelopathy was determined using the JOA score on both preoperative and postoperative images. The recovery rate was also calculated. The Pavlov ratio in plain radiographs from patients with myelopathy was compared with the ratio of the vertebral body to the spinal canal on CT and MRI.
The average Pavlov ratio between C3 and C6 ranged from 0.71 to 0.76. On CT scan, the average vertebral body-to-canal ratio between C3 and C6 ranged from 0.62 to 0.66. On MRI, the vertebral body-to-CSF column ratio between C3 and C6 ranged between 0.53 and 0.57. A positive correlation was noted between the Pavlov ratio and the vertebral body-to-canal ratio on sagittal-reconstruction CT (correlation coefficient = 0.497-0.627, p = 0.000) and between the Pavlov ratio and the vertebral body-to-CSF column ratio on MRI (correlation coefficient = 0.511-0.649, p = 0.000).
We demonstrated a good correlation between the Pavlov ratio and both the vertebral body-to-canal ratio on CT and the vertebral body-to-CSF column ratio on MRI. Therefore, the Pavlov ratio can be relied upon to predict narrowing of the cervical spinal canal in the sagittal plane.
Cervical spine; Myelopathy; Pavlov ratio
To investigate the feasibility and sample size required for a full-scale randomised controlled trial of the effectiveness of acupuncture with non-steroidal anti-inflammatory drugs (NSAIDs) for chronic neck pain compared with acupuncture or NSAID treatment alone.
A total of 45 patients with chronic neck pain participated in the study. For 3 weeks the acupuncture with NSAIDs treatment group took NSAIDs (zaltoprofen, 80 mg) daily while receiving acupuncture treatment three times a week. The acupuncture treatment group received treatment three times a week and the NSAID treatment group took NSAIDs daily. The primary outcomes were to determine the feasibility and to calculate the sample size. As secondary outcomes, pain intensity and pain-related symptoms for chronic neck pain were measured.
With regard to enrolment and dropout rates, 88.2% of patients consented to be recruited to the trial and 15.6% of participants were lost to follow-up. The sample size for a full-scale trial was estimated to be 120 patients. Although preliminary, there was a significant change in the visual analogue scale (VAS) for neck pain intensity between the baseline measurement and each point of assessment in all groups. However, there was no difference in VAS scores between the three groups.
This pilot study has provided the feasibility and sample size for a full-scale trial of acupuncture with NSAIDs for chronic neck pain compared with acupuncture or NSAID treatment alone. Further research is needed to validate the effects of acupuncture with NSAIDs.
Clinical Trial Registration
NIH ClinicalTrials.gov NCT01205958.
ACUPUNCTURE; PAIN MANAGEMENT; COMPLEMENTARY MEDICINE