Bong Ju Moon

Polymethylmethacrylate-Augmented Screw Fixation for Stabilization of the Osteoporotic Spine : A Three-Year Follow-Up of 37 Patients

OBJECTIVE The purpose of this study was to determine the efficacy, radiological findings, clinical outcomes and complications in patients with lumbar stenosis and osteoporosis after the use of polymethylmethacrylate (PMMA) augmentation of a cannulated pedicle screw. METHODS Thirty-seven patients with degenerative spinal stenosis and osteoporosis (T-score < -2.5) underwent lumbar fusion using the Dream Technology Pedicle Screw (DTPS, Dream Spine Total Solutions, Dream STS, Seoul, Korea) between 2005 and 2007. The clinical outcomes were evaluated by using the visual analog scale (VAS) and the Prolo scale. Radiologic findings were documented through computed tomography (CT) and plain films. RESULTS Thirty-seven patients were evaluated and included, 2 males and 35 females with an average bone mineral density (BMD) of 0.47g/cm(2). The average age of the patients was 68.7 (range, 57-88). The preoperative VAS for low back and leg pain (7.87 +/- 0.95 and 8.82 +/- 0.83) were higher as compared with postoperative VAS (2.30 +/- 1.61 and 1.42 +/- 0.73) with statistical significance (p = 0.006, p = 0.003). According to the Prolo scale, 11, 22, one and three patients were in excellent, good, fair and poor conditions, respectively. The average amount of the injected cement per one cannulated screw was 1.83 +/- 0.11 mL. CONCLUSION The results show favorable outcome both clinically and radiographically for 37 patients who underwent lumbar fusion using DTPS and PMMA. Based on the results, the use of this surgical method can be a safe and effective option for the operation on the osteoporotic spine.

Prevalence, Distribution, and Significance of Incidental Thoracic Ossification of the Ligamentum Flavum in Korean Patients with Back or Leg Pain : MR-Based Cross Sectional Study

Objective Thoracic ossification of the ligamentum flavum (OLF) is a relatively rare disease. Because of ambiguous clinical symptom, it is difficult for early diagnosis of OLF and subsequent treatment can be delayed or missed. Therefore, the purpose of this study is to comprehensively assess the prevalence and distribution of thoracic OLF by magnetic resonance imaging (MRI) and coexisting spinal disease in Korean patients with back pain or leg pain. Methods The sample included 2134 Korean patients who underwent MRI evaluation for back pain. The prevalence and distribution of thoracic OLF were assessed using lumbar MRI with whole spine sagittal images. Additionally, we examined the presence of coexisting lumbar and cervical diseases. The presence of thoracic OLF as well as clinical parameters such as age, sex, and surgery were retrospectively reviewed. Results The prevalence of thoracic OLF in total patients was 16.9% (360/2134). The prevalence tended to increase with aging and was higher in women than in men. The lower thoracic segment of T10-11 was the most frequently affected segment. Of the 360 patients with OLF, 31.9% had coexisting herniated thoracic discs at the same level. Approximately 74% of the patients with OLF had coexisting lumbar and cervical disease. Nine (2.5%) of 360 OLF patients underwent surgery for thoracic lesion. Conclusion The prevalenceof thoracic OLF was relatively higher than those of previous reports. And coexisting lumbar and cervical disease were very frequent. Therefore, we should check coexisting spinal diseases and the exact diagnostic localization of ossification besides lumbar disease.

Prevalence and type of cervical deformities among adults with Parkinson's disease: a cross-sectional study.

OBJECT To identify the characteristics of cervical deformities in Parkinsons disease (PD) and the role of severity of PD in the development of cervical spine deformities, the authors investigated the prevalence of the cervical deformities, cervical kyphosis (CK), and cervical positive sagittal malalignment (CPSM) in patients with PD. They also analyzed the association of severity of cervical deformities with the stage of PD in the context of global sagittal spinopelvic alignment. METHODS This study was a prospective assessment of consecutively treated patients (n = 89) with PD. A control group of the age- and sex-matched patients was selected from patients with degenerative cervical spine disease but without PD. Clinical and demographic parameters including age, sex, duration of PD, and Hoehn and Yahr (H&Y) stage were collected. Full-length standing radiographs were used to assess spinopelvic parameters. CK was defined as a C2-7 Cobb angle < 0°. CPSM was defined as C2-7 sagittal vertical axis (SVA) > 4 cm. RESULTS A significantly higher prevalence of CPSM (28% vs. 1.1%, p < 0.001), but not CK (12% vs. 10.1%, p = 0.635), was found in PD patients compared with control patients. Among patients with PD, those with CK were younger (62.1 vs. 69.0 years, p = 0.013) and had longer duration of PD (56.4 vs. 36.2 months, p = 0.034), but the severity of PD was not significantly different. Logistic regression analysis revealed that the presence of CK was associated with younger age, higher mismatch between pelvic incidence and lumbar lordosis, and lower C7-S1 SVA. The patients with CPSM had significantly greater thoracic kyphosis (TK) (p < 0.001) and a trend toward more advanced H&Y stage (p = 0.05). Logistic regression analysis revealed that CPSM was associated with male sex, greater TK, and more advanced H&Y stage. CONCLUSIONS Patients with PD have a significantly higher prevalence of CPSM compared with age- and sex-matched control patients with cervical degenerative disease but without PD. Among patients with PD, CK is not associated with the severity of PD but is associated with overall global sagittal malalignment. In contrast, the presence of CPSM is associated more with the severity of PD than it is with the presence of global sagittal malalignment. Collectively, these data suggest that the neuromuscular pathogenesis of PD may affect the development of CPSM more than of CK.

Subsidence after single-level anterior cervical fusion with a stand-alone cage

To investigate the risk factors for subsidence in patients treated with stand-alone anterior cervical discectomy and fusion (ACDF) using polyetheretherketone (PEEK) cages for single-level degenerative cervical disease. Seventy-seven consecutive patients who underwent single-level stand-alone ACDF with a PEEK cage between 2005 and 2012 were included. Subsidence was defined as a decrease in the interbody height of more than 3mm on radiographs at the 1-year follow-up compared with that in the immediate post-operative image. Patients were divided into the subsidence and non-subsidence groups. The following factors were investigated in relation to the occurrence of subsidence: age, pre-operative overall cervical sagittal angle, segmental angle of the operated level, interbody height, cage height, cage devices and cage location (distance between anterior margin of the body endplate and that of the cage). The clinical outcomes were assessed with visual analog scale, modified Japanese Orthopedic Association score and neck disability index. Twenty-six out of the 77 (33.8%) patients had radiological signs of cage subsidence. Solid fusion was achieved in 25 out of the 26 patients (96.2%) in the subsidence group and in 47 out of the 51 patients (92.2%) in the non-subsidence group. More than 3mm distance between anterior margin of the vertebral body and that of the cage was significantly associated with subsidence (p<0.05). However, subsidence did not correlate with fusion rate or clinical outcomes. Cage location was the only significant risk factor. Therefore, cage location should be taken into consideration during stand-alone ACDF using PEEK cages.

Is stand alone PEEK cage the gold standard in multilevel anterior cervical discectomy and fusion (ACDF)? Results of a minimum 1-year follow up

INTRODUCTION This study was designed to evaluate the clinical and radiologic results of stand-alone synthetic polyetheretherketone (PEEK) cages for two- or three-level anterior cervical discectomy and fusion (ACDF), with a focus on subsidence. MATERIALS AND METHODS We retrospectively reviewed a total of 68 patients who underwent two- or three-level ACDF with a stand-alone PEEK cage between April 2005 and August 2016. Radiologic parameters were assessed on lateral radiographs, and fusion was assessed on computed tomography scans. For the evaluation of clinical outcomes, visual analogue scale, neck disability index, and modified Japanese Orthopedic Association scores were measured. RESULTS Among the total of 68 patients with a total of 144 segments, ACDF at two and three levels was performed in 60 and 8 patients, respectively, with a mean follow-up duration of 27.6 months. The overall fusion rate was 81.3% (117 of 144 segments), and subsidence occurred in 63 segments (43.8%) at the last follow-up. There was no statistically significant difference between the subsidence group and the nonsubsidence group in terms of fusion rate, radiologic outcomes, and clinical outcomes (p > .05). CONCLUSION Subsidence might be an inevitable course and only a radiologic phenomenon with no effect on the clinical and radiologic outcomes of the use of stand-alone cages.

Cervical Myelopathy Caused by Bilateral Laminar Cleft of the Axis: Case Report and Review of Literature.

BACKGROUND Cervical myelopathy due to bilateral laminar cleft of the axis is extremely rare, and few cases have been previously reported. However, its treatment is relatively simple. Surgical removal of the anomalous bony structure compromising the spinal canal can sufficiently achieve a good outcome. CASE DESCRIPTION A 56-year-old man presented with a 2-year history of stiffness of the left upper and lower extremities. Cervical spine computed tomography showed a bony cleft at both laminae of the posterior arch of the axis, with obvious cord compression on magnetic resonance imaging. Although absence of right pedicle and spina bifida of C7 were also detected, there was no cord compression at this level. The patient underwent surgical removal of the anomalous laminar cleft and the spinous process of the axis. Postoperatively, he improved rapidly and was discharged on the seventh postoperative day. He was asymptomatic at the 3-year follow-up. After surgery, the preoperative myelopathy status was much improved. About 7 years after surgery, radiographs showed no kyphosis and instability. CONCLUSION Invaginated bilateral laminar cleft of the axis is a rare cause of cervical myelopathy. The findings in our case should broaden the radiographic differential diagnosis in patients with cervical myelopathy. Surgical removal is an appropriate and simple treatment for this patient, resulting in a satisfactory outcome.

Langerhans cell histiocytosis in the adult lumbar spine: case report

IntroductionLangerhans cell histiocytosis (LCH) occurs rarely in the spine of adults. The radiological findings usually resemble vertebral tumors. Etiology of LCH has not been clearly established yet. Therapeutic approaches are still controversial. We describe a case of LCH in an adult spine.Case descriptionA patient who presented with low back pain had an osteolytic lesion in the L1 vertebral body without neurological deficits, and fluoroscopy-guided needle biopsy of the L1 vertebral body was performed. The immunohistochemical diagnosis confirmed LCH. The patient was successfully treated with conservative methods.DiscussionThe choice of appropriate therapy is very important, with treatment options varying from watch-and to aggressive treatment.ConclusionLCH is considered as a pediatric disease that is extremely rare in the spine of adults and should be include in the differential diagnosis of osteolytic vertebral lesions. Conservative treatment is best choice for a patient with LCH without neurological deficit or spinal instability.

Posterior Cervical Microscopic Foraminotomy and Discectomy with Laser for Unilateral Radiculopathy

Surgical decompression for cervical radiculopathy includes anterior cervical discectomy and fusion, anterior or posterior cervical foraminotomy, and cervical arthroplasty after decompression. The aim of this study was to evaluate the usefulness of a CO2 laser in posterior-approach surgery for unilateral cervical radiculopathy. From January 2006 to December 2008, 12 consecutive patients with unilateral cervical radiculopathy from either foraminal stenosis or disc herniation, which was confirmed with imaging studies, underwent posterior foraminotomy and discectomy with the use of a microscope and CO2 laser. For annulotomy and discectomy, we used about 300 joules of CO2 laser energy. Magnetic resonance imaging (MRI) was used to evaluate the extent of disc removal or foraminal decompression. Clinical outcome was evaluated by using visual analogue scale scores for radicular pain and Odoms criteria. For evaluation of spinal stability, cervical flexion and extension radiographs were obtained. Single-level foraminotomy was performed in 10 patients and two-level foraminotomies were performed in 2 patients. Preoperative radicular symptoms were improved immediately after surgery in all patients. No surgery-related complications developed in our cases. Postoperative MRI demonstrated effective decompression of ventral lesions and widened foraminal spaces in all cases. There was no development of cervical instability during the follow-up period. Posterior foraminotomy and discectomy using a microscope and CO2 laser is an effective surgical tool for unilateral cervical radiculopathy caused by lateral or foraminal disc herniations or spondylotic stenosis. Long-term follow-up with radiographs showed no significant kyphotic changes or spinal instability.

Clinical Outcomes and Prognostic Factors in Patients With Myelopathy Caused by Thoracic Ossification of the Ligamentum Flavum

Objective The objective of this study was to investigate the surgical outcomes and prognostic factors for thoracic ossification of the ligamentum flavum (OLF) after decompressive laminectomy, focusing on the quantitative signal intensity ratio (SIR) of preoperative magnetic resonance imaging (MRI) and its prognostic significance. Methods We retrospectively reviewed 24 patients who previously underwent total laminectomy to remove OLF from 2010 to 2015. MRI and computed tomography were performed to detect OLF. The SIR between the regions of interest of high signal intensity lesions and the normal cord at the T1–2 disc levels was calculated. We divided patients into 2 groups based on the extent of the modified Japanese Orthopaedic Association (JOA) recovery rate (RR): good (RR ≥ 50%) and poor (RR < 50%). Results The mean preoperative and postoperative modified JOA scores for thoracic myelopathy were 6.67 ± 1.73 and 8.63 ± 1.81, respectively (p < 0.001). The preoperative JOA score (7.5 vs. 5.83, p = 0.028), postoperative JOA score (9.83 vs. 7.42, p = 0.000), and SIR (1.16 vs. 1.41, p = 0.009) were significantly different between the good and poor RR groups. A higher preoperative JOA score and lower SIR were associated with a good RR according to the JOA criteria. Conclusion The clinical outcomes for thoracic OLF after decompressive laminectomy were favorable. A higher RR was correlated with a lower SIR and higher preoperative modified JOA score. Therefore, a relatively low SIR on MRI and a relatively high preoperative JOA score could be positive prognostic indicators for the JOA RR in patients with thoracic OLF.

Acute transverse myelitis following scrub typhus: A case report and review of the literature

Context: Scrub typhus is an acute febrile disease caused by Orientia tsutsugamushi. The disease can usually involve the lungs, heart, liver, spleen and brain through hematogenous dissemination. However, very rarely, acute transverse myelitis in the spinal cord develops from scrub typhus. We present a case of acute transverse myelitis following scrub typhus with a review of the literature. Findings: A 66-year-old male visited a hospital for general myalgia, mild headache, and fever in October. He was noted to have thick, black papule skin on his abdomen, which was highly suggestive of scrub typhus. To confirm the diagnosis, O. tsutsugamushi antibody titers were examined and detected highly in serum by an indirect fluorescence antibody assay. Doxycycline, the standard treatment for scrub typhus, was administered. However, after seven days of treatment, he rapidly developed weakness in the right leg, paresthesia in both lower limbs, and voiding difficulty. Spinal magnetic resonance imaging (MRI) revealed lesions with high signal intensity involving the spinal cord at the thoracolumbar junction. Paraparesis gradually improved following steroid pulse therapy for five days. At one-year follow-up, he could walk without cane. Conclusions: Orientia tsutsugamushi causes scrub typhus, which can affect not only the brain, but also the spinal cord. Although acute transverse myelitis develops rarely from scrub typhus, this should be considered as differential diagnosis in patients of fever with neurological deficit in endemic areas.