KJC Korea
Journal Central

Study Design: Retrospective risk-factor analysis Objectives: This study investigated the clinical and radiological risk factors associated with the progression of osteoporotic spinal fractures (OSFs) after conservative treatment. Summary of Literature Review: Nonunion and cleft signs on radiographs are strongly associated with complicated osteoporotic spinal fractures. Materials and Methods: From Jan. 2005 to Dec. 2007, 84 patients (15 males and 69 females; mean 72.6 yrs) were enrolled in this retrospective review. The progressive OSF, clinical and radiological factors were analyzed considering the progression of the kyphotic angle (PKA>20˚) and the presence of intravertebral cleft signs (IVC). Age, gender, body mass index, vertebral level involved, BMD score, MRI classification and initial kyphotic angle were adopted for the analysis. For statistical analysis, a chisquare test was performed to analyze the relationship between each factor and multiple logistic regression analysis was performed to analyze the multifactorial explanatory factor. Results: The presence of IVC was related to the thoracolumbar fracture, mid-portion MR classification and high body mass index. PKA>20˚was related to the thoracolumbar fracture and mid-portion classification. For multifactorial analysis using these seven factors, two factors (the level of fracture and MR classification) were found to be associated with the presence of IVC with statistical significance. In the thoracolumbar fracture, the incidence of IVC was 5.2 times higher than the other levels. The incidence of IVC in endplate classification was 16% lower than in the mid-portion. Conclusion: BMI, the fracture level involved and MR classification were associated with the development of IVC and PKA>20˚ for a conservative treatment of OSF. Multiple logistic analysis revealed the level of the fracture and MR classification to be significant.

Study design: Retrospective study Objectives: To examine the effect of transpedicular screw fixation on fractured vertebrae about the vertebral wedge angle (VWA) after posterior instrumentation of the thoracolumbar fracture, determine the effect of reduced VWA on the change in the Kyphotic angle (KA), and minimize loss of reduction of KA. Summary of the literature review: Maintenance of the KA of a thoracolumbar fracture after surgery is important for the radiologic and functional outcome. Materials and methods: Forty patients, who had undergone posterior instrumentation in a thoracolumbar fracture between February 2006 and February 2008 and followed-up for more than one year, were enrolled in this study. The patients were divided into two groups according to transpedicular screw fixation (Group A) or not (Group B) including fractured vertebrae. The evaluation was performed by measuring the changes in the KA and VWA taken after the injury, immediate after surgery and 1 year after surgery. Results: There was correlation between groups A (transpedicular screw fixation on fractured vertebrae) and B (no transpedicular screw fixation on the fractured vertebrae) regarding the correction of the VWA and the loss of correction KA, (p<0.05). Conclusions: Reduction of the VWA is an important factor for preventing reduction loss of the KA, and transpedicular screw fixation including fractured vertebrae would help reduce the VWA. Therefore, the operator must pay attention to the increase in VWA to maintain the KA through short segment transpedicular screw fixation including fractured vertebrae.

Study Design: Prospective study Objectives: To analyze and compare the cervical and thoracic sagittal curves between normal adolescents and patients with thoracic adolescent idiopathic scoliosis (AIS). Summary of Literature Review: There are no reports on cervical sagittal curves and its correlation with thoracic sagittal curves in AIS. Materials and Methods: The sagittal curves were analyzed in normal adolescents (N-adol group, n=23) and patients with thoracic AIS (AIS group, n=26) who had thoracic curves ≥ 45˚. Lateral standing radiographs of the cervical spine with a elbow straight and the whole spine with the hands on the clavicles were taken. The sagittal curves and balance were measured in the following segments; C2-C7, T2-T5, T5-12, T2-12, T12-S1. Cervical lordosis (C2-C7) was measured in both cervical spine radiographs and whole spine radiographs. Results: In the N-adol group, the cervical lordosis was 9.2±14.6˚in the cervical spine radiographs and -0.6±12.9˚(‘-’ means kyphosis) in whole spine radiographs. In the AIS group, cervical lordosis was -5.0±12.9˚in the cervical radiographs and -8.1± 12.7˚in the whole radiographs. The AIS group had significantly less cervical lordosis than the N-adol group. Thoracic kyphosis of T5-12 and T2-12 was 24.1±10.6˚and 38.9±13.1˚in the N-adol group, respectively, and 17.8±9.4˚and 30.1±11.8˚in the AIS group, respectively. There was a significant difference between the two groups (Ps<0.05). There was no significant difference in thoracic kyphosis of T2-T5, lumbar lordosis and sagittal balance between the two groups (Ps>0.05). In the AIS group, the cervical lordosis measured in the cervical spine radiograph showed a positive correlation with thoracic kyphosis of T2-5 (r=0.50, P=0.009) and T2-12 (r=0.57, P=0.003). Conclusions: AIS patients had significantly less cervical lordosis and thoracic kyphosis than normal adolescents. Decreased cervical lordosis in AIS had a significant correlation with their relative thoracic hypokyphosis.

Study Design: Retrospective study Objectives: This study examined the effect of a TLSO brace treatment for the correction of axial rotational deformities in idiopathic scoliosis. Summary of Literature Review: A TLSO brace treatment is effective in correcting 2-dimensional deformities of idiopathic scoliosis but is questionable in axial rotational deformities. Materials and Methods: Fifty three cases treated by bracing in March, 1999~February, 2005 at our department were reviewed. The posteroanterior and lateral radiographs were checked in the standing position throughout the study. The change in axial rotational deformity were analyzed using Nash & Moe method and Perdriolle’s method. Results: The rotational deformity had improved in 2 curves, was aggravated in 8 curves, and showed no change in 43 curves with the TLSO brace. Conclusions: The TLSO brace treatment in axial rotational deformity of idiopathic scoliosis is not effective in correcting the rotational deformity but is effective in preventing the progress of a rotational deformity.

Study Design: This is a retrospective study Objectives: We radiologically analyzed the correction of the sagittal imbalance and the proximal fusion level to prevent correction loss and the usefulness of iliac screws in LDK. Summary of the Literature Review: Complications can be encountered during fixation and fusion as most of the LDK patients are aged, and the osteoporosis that causes fixation loss is known to affect the loss of correction. Materials and Methods: We analyzed the cause of correction loss among 35 patients who underwent surgery and who were followed up for at least 1 year. All the patients had performed gait analysis before operation. The operative techniques were pedicle subtraction osteotomy and fixation to S1. For analyzing causes of correction loss, we analyzed the degrees of lumbar lordosis for the sagittal correction and the degrees of the preoperative thoracolumbar kyphosis for the proximal fusion range. For analyzing the usefulness of iliac screws, the subjects were divided into two groups: 1) the -iliac screw (23cases) group for the patients who were fixed without iliac screws and 2) the +iliac screw (12cases) group for the patients who were fixed with iliac screws. Results: There were no patients who had marked anterior pelvic tilt. It is important to correct the lumbar lordosis over 20˚compared with the preoperative thoracic kyphosis. There are 10 cases of preoperative thoracolumbar kyphosis ≥ 10˚and 25 cases of preoperative thoracolumbar kyphosis < 10˚of the total 35 cases. Among 10 cases of preoperative thoracolumbar kyphosis ≥ 10˚, 4 cases that were fixed to T10 had no sagittal correction loss, and 2 of the 6 cases that were fixed to T11 or T12 had sagittal correction loss. For the 25 cases of preoperative thoracolumbar kyphosis < 10˚, 5 cases that were fixed to T10 had no sagittal correction loss and 1 of the 20 cases that were fixed to T11 or T12 had sagittal correction loss (p<0.05). 6 cases (26%) in the -iliac screw group (23 cases total) and 1 case (8%) in the +iliac screw (12 cases total) showed sagittal correction loss (p<0.05). Conclusions: It is important to make the postoperative lumbar lordosis over 20。compared with the preoperative thoracic kyphosis for correcting sagittal imbalance, to decide on the proximal fixation level according to the preoperative thoracolumbar kyphosis and to fix with iliac screws.

Study Design: A prospective, non-randomized study Objectives: To evaluate the early clinical results of percutaneous endoscopic lumbar discectomy (PELD) and microdiscectomy (MD) using a tubular retractor. Summary of the Literature Review: There are few reports comparing the clinical results of different minimal invasive surgical procedures for disc herniation. Materials and Methods: Out of 41 patients who underwent a discectomy at the L4-5 level, 16 patients (Group Ⅰ) underwent PELD and 25 patients (Group Ⅱ) underwent MD. The surgical techniques were based on the patient’s selection. The characteristics of the operation(operation time, time for C-arm, amount of removed disc) were compared with the clinical outcomes by evaluating the SLR (straight leg raising test), leg VAS (visual analogue scale), ODI (Oswestry Disability Index), hospital day, changes in disc height. Results: Group I showed a larger amount of disc removed and exposure time for the C-arm than group Ⅱ (p<0.05). However, the hospital day was shorter in group I than in group Ⅱ (p<0.05). There were no differences in the leg VAS, ODI, the change in disc height and surgery time between the two groups at the last follow up. One case in group I had a neuropraxia of the L5 root that had recovered fully at postoperative 3months. In group Ⅱ, there was one case of a postoperative hematoma and 2 cases of a dural tear. Conclusion: Although the early clinical outcomes were similar in both groups, group Ⅰ showed a larger amount of disc removed and more exposure time to radiation but a shorter hospital stay.

Study Design: A prospective study Objectives: We wanted to assess the clinical outcomes of posterior dynamic stabilization with selective wide decompression for treating multilevel lumbar stenosis in old age. Summary of Literature Review: Deciding on the segments to be operated on is challenging problem for old age patients with multilevel lumbar stenosis. There have been no reports on posterior dynamic stabilization with selective wide decompression for treating multilevel lumbar stenosis. Materials and Methods: We evaluated 18 patients who underwent posterior dynamic stabilization with selective decompression for multilevel disc degeneration and spinal stenosis. The mean age was 70.2 years and mean follow-up was 15.1 months. We evaluated the segmental angle, the range of motion (ROM) and pedicle screw loosening. The clinical results were evaluated according to the operative time, blood loss, the visual analogue scale (VAS) for the back pain and leg pain and and the Oswestry disability index (ODI). Results: The mean number of operated segments was 2.16. The lordosis of the lumbar and operated segments showed no significant difference. However, the ROM of the total lumbar spine and the operation segment was significantly decreased from 36.8 to 24.3 and 22.9 to 13.1, respectively. The ROM for the adjacent segment did not show a significant difference. A radiolucent line around the pedicle screw appeared at 22 screws (19.3%) out of a total 114 screws. The VAS for back and leg pain were improved from 7.5 and 8.6 to 2.3 and 2.1, respectively. The ODI was improved from 41.5 to 13.4. Conclusions: The initial clinical outcomes were favorable after posterior dynamic stabilization with selective decompression. This procedure could be considered to be a useful option for treating multilevel stenosis in old age patients.

Study design: A retrospective study. Objective: To analyze the clinical significance of the radiolucent zones surrounding pedicle screws. Summary of Literature Review: Clear zones have been suggested in pseudoarthrosis and a loss of fixation. However, few reports have clearly described the long-term course and clinical significance of clear zones. Materials and Methods: The clear zones were evaluated in 399 patients with pedicle screw fixation after 6 months, 1 year, 2 years and 3 years. The patient was considered to be clear zone positive when 1 mm or greater circumferential lucency was confirmed around a screw on film from 2 or more directions. The time-course of the clear zones was examined with regard to age, number of levels fused, bone union, fusion method and reoperation. Results: After 6 months, clear zones were observed in 124 patients (31.1%) but the clear zone-positive rate decreased with time. Clear zones were observed in 89 patients(22.3%), 44 patients(11.0%) and 41 patients(10.3%) after 1 year, 2 years and 3 years, respectively. No new clear zones had developed after 6 months. At the final follow-up, pseudoarthrosis was observed in 12 patients(3.0%). Among them, 11 were clear zone-positive and 1 was clear zone-negative. There was a statistically significant relationship between the clear zone-positive rate and multi-levels, older age and nonunion during following up. In addition, there was a relatively lower clear zone-positive rate in posterolateral fusion combined with posterior lumbar interbody fusion than only posterolateral fusion. However, the difference between them was not statistically significant. Conclusion: The presence of clear zones does not always mean pseudoarthrosis but clear zones persisting for more than 2 years after surgery have a higher rate of pseudoarthrosis.

Cervical spondylolysis is defined as a corticated cleft between the superior and inferior articular facets of the articular pillar, which is the cervical equivalent of pars interarticularis in the lumbar spine. It is very important to avoid confusion with more clinically significant abnormalities, such as fracture or dislocation. This case report describes bilateral spondylolysis and associated dysplasia of C6. We describe the radiographic presentation of this anomaly, stressing the importance of computed tomography and magnetic resonance imaging for a correct diagnosis. A review of the literature on this interesting abnormality and a complete differential diagnosis are presented.

Spinal arachnoid cysts are a rare disease with an unknown origin. Because of their broad base, a total laminectomy with or without fusion has been the treatment of the choice. We encountered 5 patients with a spinal arachnoid cyst who were treated by recapping laminoplasty after pars osteotomy. This procedure has not been reported in Korea. All patients showed neurological recovery with no recurrence of the cyst. The findings on the stressed plain film confirmed bony union and stability of the posterior element. No complications such as postoperative spinal canal stenosis, facet arthrosis or kyphosis were observed. Among the various surgical options for the extirpation of arachnoid cysts, recapping laminoplasty appears to be a good but technically demanding procedure.

To our knowledge, there are no reported cases of rectal fistula complicating spondylodiscitis. We report the first case of a rectal fistula communicating with the site of postoperative recurrent spondylodiscitis. A-59-year-old female had recurrent spondylodiscitis after an open discectomy for L5-S1 eight years earlier. She underwent three operations including two anterior lumbar interbody fusion procedures after an open discectomy. Radiographic studies revealed severe bony destruction with abscess collection within the L5-S1 intervertebral disc space with fistula formation into the rectum. The fistula was confirmed by a Barium enema colon study and sigmoidscopy. The patient underwent a staged operation consisting of a rectosigmoid colon resection, anterior interbody fusion and posterior instrumented fusion. Rectum related complications were suspected in this case of recurrent spondylodiscitis.

The etiology of spondylolisthesis, which determines the pathoanatomy and natural course, includes the abnormal development of lumbosacrum and various acquired conditions. Many patients with symptomatic degenerative and isthmic spondylolisthesis respond to non-surgical treatments, such as modification of their daily activity, medication, physical therapy and nerve block. Surgical treatment is indicated for intractable pain, neurological symptoms and the progression of slip. The natural course and patient’s demographics are also considered. Decompression of the neural stenosis and the fusion of segmental instability are the main surgical treatments of degenerative and isthmic spondylolisthesis Fusion and instrumentation should be chosen carefully for degenerative spondylolisthesis if it is stable. However, solid fusion is the most important procedure for isthmic spondylolisthesis. Anterior lumbar interbody fusion is an effective treatment regarding an anatomical restoration of slip, decompression of neural structures and optimal fusion for degenerative and isthmic spondylolisthesis.