Percutaneous Pedicle Screw Fixation in Thoracolumbar Fractures: Comparison of Results According to Implant Removal Time

BACKGROUND: The purpose of this study was to determine whether restoration of range of motion (ROM) could be achieved by implant removal after natural bone healing and consolidation of fractured vertebrae and examine whether early removal of the implant could maximize restoration of ROM. METHODS: This study included 30 cases of thoracolumbar fractures without neurological deficit requiring surgery (nine cases of flexion-distraction injuries and 21 cases of burst fractures). Percutaneous pedicle screw fixation (PPSF) was performed at the fractured vertebrae and one level above and one level below the fracture level. Pedicle screws were removed at an average of 12 months after surgery upon healing of fractured vertebrae. The following radiological and clinical findings were evaluated: restoration of anterior vertebral height ratio (AVHR), Cobb angle (CA), ROM, and complications. Sixteen patients who were checked for ROM were divided into two groups based on the time of implant removal: nine patients within 12 months and seven patients after 12 months. Restoration of vertebral height loss and ROM were compared between the two groups. RESULTS: At the final follow-up, significant pain relief and restoration of AVHR and CA were achieved in patients who underwent PPSF. Patients who had implant removed within 12 months after surgery had better ROM recovery than those who had implant removed after 12 months postoperatively. There were no significant differences in AVHR and CA between the two groups. CONCLUSIONS: PPSF followed by implant removal after healing of fractured body appears to be effective in achieving restoration of ROM. In our study, early removal of implant within 12 months after surgery was associated with better achievement of ROM than removal after 12 months. In addition, there were no significant differences in restoration of vertebral height between the two groups.

The Need for Early Tracheostomy in Patients with Traumatic Cervical Cord Injury

BACKGROUND: In patients who need sustained endotracheal intubation and mechanical ventilation due to respiratory failure after traumatic cervical spinal cord injury, tracheostomy can be performed to reduce the duration of mechanical ventilation and respiratory complications. The purpose of this study was to determine criteria and timing of tracheostomy in patients with severe traumatic cervical spinal cord injury accompanied by motor weakness. METHODS: We reviewed 22 patients who underwent tracheostomy (study group) and 27 patients who did not (control group) from January 2005 to March 2016. We assessed the American Spinal Injury Association (ASIA) impairment scale score and investigated accompanying thoracic injury, paradoxical respiration, postoperative endotracheal intubation and other clinical parameters. The study group was also subdivided into the early tracheostomy group and late tracheostomy group depending on whether the tracheostomy was performed within or later than 7 days after surgery. RESULTS: Twenty-two patients in the study group had a mean ASIA impairment scale score of 14.1 points, which was lower than the control group's 23.4 points. Paradoxical respiration was observed in 77% of the patients in the study group compared to 18% in the control group. Postoperative intubation was maintained in 68% in the study group; 32% underwent endotracheal intubation due to respiratory failure within 4 days after surgery and had a tracheostomy. In the control group, postoperative intubation was maintained in 22%, and all of them were weaned off intubation within 4 days after surgery. The duration of intensive care unit hospitalization was 11.4 days for the early tracheostomy group, which was shorter than the late tracheostomy group's 19.7 days. CONCLUSIONS: In patients with severe traumatic cervical spinal cord injury, tracheostomy may be needed when the motor grade of the ASIA scale is low, above the C4 segment is injured, or paradoxical respiration occurs after injuries. In addition, if endotracheal extubation is not feasible within 4 days after surgery, an early tracheostomy should be considered.

Quality of Life in Patients with Osteoporotic Vertebral Compression Fractures

BACKGROUND: This study aimed to evaluate quality of life (QOL) using the EuroQOL-5 dimensions (EQ-5D) index and to examine factors affecting QOL in patients with an osteoporotic vertebral compression fracture (OVCF). METHODS: This ambispective study used a questionnaire interview. Patients over 50 years old with an OVCF at least 6 months previously were enrolled. Individual results were used to calculate the EQ-5D index. Statistical analysis was performed, and factors related to QOL were examined. RESULTS: Of 196 patients in the study, 84.2% were female, with an average age of 72.7 years. There were 66 (33.7%) patients with multilevel fractures. Conservative management was used in 75.0% of patients, and 56.1% received anti-osteoporosis treatment. The mean EQ-5D index was 0.737±0.221 and was significantly correlated with the Oswestry disability index score (correlation coefficient −0.807, P<0.001). The EQ-5D index was significantly correlated with age (Spearman's rho=−2.0, P=0.005), treatment method (P=0.005), and history of fracture (P=0.044) on univariate analysis and with conservative treatment (P<0.001) and osteoporotic treatment (P=0.017) on multivariate analysis. CONCLUSIONS: OVCF markedly lowers QOL in several dimensions for up to 12 months, even in patients who have healed. Treatment of osteoporosis and conservative treatment methods affect QOL and should be considered in OVCF management.

Pneumocephalus after Interlaminar Lumbar Epidural Block / 대한정형외과학회잡지

Lumbar epidural block using a “loss of resistance” technique (LORT) with air can potentially cause pneumocephalus. Herein, we present a pneumocephalus that occurred after an epidural block. A 58-year-old male patient underwent an interlaminar lumbar epidural block using a LORT with air for L4–5 disc herniation. After the block, the patient complained of headache, vomiting, and truncal myoclonus. For further evaluation, a brain computed tomography was performed, and pneumocephalus was finally diagnosed. The patient underwent conservative treatment and recovered without any complications. He was discharged on the 11th day after the block.

Validity of the Thoracolumbar Injury Classification System for Thoracolumbar Spine Injuries

STUDY DESIGN: Retrospective study. OBJECTIVES: To evaluate the validity of the thoracolumbar injury classification system (TLICS) when making treatment decisions in a group of thoracolumbar fracture patients. SUMMARY OF LITERATURE REVIEW: Few studies have evaluated the validity of the TLICS in consecutively treated patients, although many have evaluated the application of the TLICS to thoracolumbar injuries. MATERIALS AND METHODS: A retrospective study was performed among the 230 patients who were treated from 2003 to 2015 in our hospital for thoracolumbar injuries. Evaluations were made of clinical outcomes and radiologic results, and each case was analysed and scored according to the American Spinal Injury Association scale, the Magerl/AO classification, and the TLICS classification by 2 spinal surgeons. RESULTS: Of the 230 patients, 116 (50.4%) received conservative treatment and 114 (49.6%) received surgical treatment. Of the 116 patients who received conservative treatment, 112 (96.6%) were treated according to the TLICS guidelines. Conservative treatment failed for 2 of the 4 patients (1.7%) whose treatment did not correspond with TLICS, and they required surgical treatment. Of the 114 patients who underwent surgical treatment, in 87 (76.3%) the treatment corresponded to the TLICS guidelines. CONCLUSIONS: The TLICS classification showed high validity for the conservative treatment of thoracolumbar injuries.

Efficacy of Cervical Expansive Laminoplasty for Quadriplegic Patients Without Cervical Bony Injury

STUDY DESIGN: Retrospective study. OBJECTIVES: To evaluate the efficacy of cervical expansive laminoplasty for patients with quadriplegia due to traumatic cervical spinal cord injury (SCI) without skeletal injury. SUMMARY OF LITERATURE REVIEW: There are a few studies on the surgical results for acute cervical SCI without bony injury. MATERIALS AND METHODS: From 2003 to 2010, among the patients who visited emergency room with post-traumatic quadriplegia, 12 patients who had underwent cervical expansive laminoplasty for acute cervical SCI without body injury and cord compression on MR images were included in this study. We evaluate the pre-operative swelling on MRI, the change of neurologic symptoms at pre-, post operative state, respiration state, complication and survival period. RESULTS: The average of motor index scores at the time of admission to the emergency room was 23 (4–30), and the average was changed to 29(4–43) during the follow-up period. No significant neurological improvement was observed in 11 cases except 1 case. The average time for operation after the injury was 26 hours(9–72). 4 patients showed paradoxical respiration when they first visited emergency room and the symptom continued after the operation and during follow-up periods. Another 4 patients showed paradoxical respiration after the operation. In all 8 cases who showed paradoxical respiration, tracheostomy and occasional ventilation were needed. In the follow-up period, 6 patients died due to respiratory failure within 1 year after the surgery. All these patients presented severe spinal cord edema on preoperative MRI with paradoxical respiration. CONCLUSIONS: Efficacy of expansive laminoplasty for quadriplegic patients due to acute cervical SCI without bony injury may be limited. In many patients, no significant neurological recovery was observed but it was clearly identified that prognosis was related to the grades of spinal cord edema and paradoxical respiration.

Adjacent Segment Pathology after Anterior Cervical Fusion

Anterior cervical fusion has become a standard of care for numerous pathologic conditions of the cervical spine. However, subsequent development of clinically significant disc disease at levels adjacent to fused discs is a serious long-term complication of this procedure. As more patients live longer after surgery, it is foreseeable that adjacent segment pathology (ASP) will develop in increasing numbers of patients. Also, ASP has been studied more intensively with the recent popularity of motion preservation technologies like total disc arthroplasty. The true nature and scope of ASP remains poorly understood. The etiology of ASP is most likely multifactorial. Various factors including altered biomechanical stresses, surgical disruption of soft tissue and the natural history of cervical disc disease contribute to the development of ASP. General factors associated with disc degeneration including gender, age, smoking and sports may play a role in the development of ASP. Postoperative sagittal alignment and type of surgery are also considered potential causes of ASP. Therefore, a spine surgeon must be particularly careful to avoid unnecessary disruption of the musculoligamentous structures, reduced risk of direct injury to the disc during dissection and maintain a safe margin between the plate edge and adjacent vertebrae during anterior cervical fusion.

Radiographic and Clinical Outcomes of Posterior Interbody Fusion for High-Grade Spondylolisthesis

STUDY DESIGN: Retrospective study. OBJECTIVES: To evaluate the clinical and radiological outcomes of posterior interbody fusion using pedicle screw fixation after posterior decompression for high-grade spondylolisthesis. SUMMARY OF LITERATURE REVIEW: The surgical treatment of high-grade spondylolisthesis has been controversial. However, few reports on the results of reduction and posterior interbody fusion after posterior decompression have been published. MATERIALS AND METHODS: Thirteen patients with L5-S1 high-grade spondylolisthesis (Meyerding grade III, IV) who underwent reduction and posterior interbody fusion were analyzed with at least 2 years of follow-up. The mean age of the patients (male 2, female 11) was 51 years. Classified by the type of spondylolisthesis, 10 cases were isthmic, 2 cases dysplastic, and 1 case degenerative. A visual analogue scale (VAS), the Oswestry Disability Index (ODI) score, bone union, anterior slippage, and slip angle were used in comparing clinical and radiographic outcomes. RESULTS: All cases showed improvement of preoperative symptoms. The VAS and ODI score improved from a mean of 8.9 points and 36.2 points preoperatively to 2.1 points and 10.2 points, respectively, at last follow-up. The degree of anterior slippage measured by Taillard's method was improved from a mean of 57.7% before surgery to mean of 14.6% at last follow-up. The slip angle also changed from a mean of 2.4° kyphosis before surgery to a mean of 7.6°C lordosis at last follow-up. There were two complications: infection and new radiating pain. CONCLUSIONS: Reduction and posterior interbody fusion using pedicle screw fixation after posterior decompression was a useful surgical method for high-grade spondylolisthesis that corrected lumbosacral kyphosis, filled the structural space of the anterior column, and acheived fusion of interbody movement.

Generation of Proinflammatory Mediator of Intervertebral Disc Cells by Nicotine Stimulation

STUDY DESIGN: Experimental investigation in vitro. OBJECTIVES: To evaluate the relationship between the degeneration of intervertebral disc cells, and low back pain induced by degeneration of intervertebral disc cells and increases in use of proinflammatory mediators via nicotine stimulation. SUMMARY OF LITERATURE REVIEW: Smoking is a leading cause of degeneration of intervertebral disc cells and low back pain. According to the existing literature, nicotine, one of the main ingredients in cigarettes, causes the degeneration of intervertebral disk cells including decrease of glycoprotein through generation of carboxy-hemoglobin, vasoconstriction, and disability of fibrinolysis and changes of metabolism of nucleus pulposus cells. MATERIALS AND METHODS: Annulus fibrosus of intervertebral disc and knee joint cartilage were collected from pigs; these cells were acquired by gradual enzyme decomposition. Using Trypan blue, concentration and survival rate of cells were examined; cells were inserted on alginate beads for tertiary cultivation. Nicotine was then applied at 0, 50, 100, 200 and 300 nM, respectively, and the samples were cultivated for three, six and nine days, respectively. After collecting culture fluid, it was measured for interleukin(IL)-1beta, IL-6 and IL-8 with the ELISA Test. DNA of cells used for cultivation was quantitated and the amount of the resulting proinflammatory mediator was normalized. The results were then compared with the result of same study on cartilage of porcine knee joints. RESULTS: For changes of the inflammatory mediator based on the concentration of nicotine, in nicotine stimulation with low concentration of 50 nM and the control group, there was no significant change, while transient increases of inflammatory mediator showed in nicotine stimulation with concentrations of 100, 200 nM, respectively. There was not a significant increase of IL-1beta observed in all nicotine stimulation groups; these were the same results in porcine cartilage study. The level of IL-6 in 200, 300 nM nicotine concentration showed significant increases, respectively. The level of IL-8 in high dose nicotine stimulation groups also showed significant increases of DNA on the sixth day. And in porcine cartilage study group, significant changes were observed in 200, 300 nM, but the absolute value was lower than that of annulus fibrous cells group. CONCLUSION: Inflammatory mediators such as IL-6 and IL-8 increased as the result of tertiary cultivation of annulus fibrosus cells of porcine intervertebral disk and nicotine stimulation. It is believed that the cells of the disc annulus are more sensitive than articular chondrocytes to nicotine stimulation. This may be the focus of future long-term studies effects of nicotine other inflammatory cytokines.

Comparison of Microscopic Lumbar Discectomy Between under Local and General Anesthesia in Lumbar Disc Herniation

STUDY DESIGN: Retrospective study. OBJECTIVES: To evaluate the effectiveness of microdiscectomy under local anesthesia in comparison with general anesthesia. SUMMARY OF LITERATURE REVIEW: No co RESULTS: Between both groups there is no significant operation time difference. However, the average hospital stay duration in the general anesthesia group was 7.3 days, while it was 4.7 days in the local anesthesia group (P0.05). Three patients in the general anesthesia group and 7 patients in the local anesthesia group needed a reoperation. CONCLUSIONS: A microdiscectomy under local anesthesia shows faster recovery period. But it shows also a relative high revision rate. In patients with old age and underlying disease, local anesthesia can be used for the microdiscectomy selectively and careful exploration of the herniated disc is required.

Spontaneous Reduction Finding: Magnetic Resonance Imaging Evaluation of Segmental Instability in Spondylolisthesis

STUDY DESIGN: Retrospective chart review. PURPOSE: To assess whether spontaneous reduction of spondylolisthesis, as seen on magnetic resonance imaging (MRI), is related to the degree of segmental instability and low back pain. OVERVIEW OF LITERATURE: The flexion-extension radiographs obtained in the sagittal plane are frequently used when segmental instability of spondylolisthesis is evaluated. METHODS: We retrospectively reviewed 137 patients and measured the differences of the percentage of sagittal translation and sagittal angulation to determine the segmental instability between the flexion and extension radiographs, and the spontaneous reduction on MRI. We then compared the degrees of segmental instability and the degrees of spontaneous reduction. To assess the effect of low back pain on segmental motion in regards to the flexion-extension radiographs, we compared the preoperative visual analogue scales (VAS) score for low back pain between the more and the less spontaneous reduction groups. RESULTS: The mean degree of spontaneous reduction was 5.2%. A statistically significant correlation was found between the sagittal translation on the flexion-extension radiographs and the degree of spontaneous reduction (r = 0.557, p < 0.001) and between the sagittal angulation on the flexion-extension radiographs and the degree of spontaneous reduction (r = 0.215, p = 0.012). The preoperative VAS scores for low back pain of the more spontaneous reduction group and the less spontaneous reduction group were 4.6 and 3.6 points, respectively, and this difference was statistically significant (p = 0.002). CONCLUSIONS: Spontaneous reduction of spondylolisthesis on MRI was found to be closely related to segmental instability, and the degree of spontaneous reduction seen on MRI could be useful for the evaluation of segmental instability in patients with spondylolisthesis, especially with severe low back pain.

The Efficacy and Persistence of Selective Nerve Root Block under Fluoroscopic Guidance for Cervical Radiculopathy

STUDY DESIGN: Retrospective study. OBJECTIVES: To investigate the outcomes of fluoroscopically guided selective nerve root block as a nonsurgical treatment for cervical radiculopathy. OVERVIEW OF LITERATURE: Only a few studies have addressed the efficacy and persistence of cervical nerve root block. METHODS: This retrospective study was conducted on 28 consecutive patients with radicular pain due to cervical disc disease or cervical spondylosis. Myelopathy was excluded. Cervical nerve root blocks were administered every 2 weeks, up to 3 times. Outcomes were measured by comparing visual analogue scale (VAS) scores, patient satisfaction, and medication usage before the procedure and at 1 week and 3, 6, and 12 months after the procedure. In addition, complications associated with the procedure and need for other treatments were evaluated. RESULTS: The average preoperative VAS score was 7.8 (range, 5 to 10), and this changed to 2.9 (range, 1 to 7) at 3 months and 4.6 (range, 2 to 7) at 12 months. Patient satisfaction was 71% at 3 months and 50% at 12 months. Five patients used medication at 3 months, whereas 13 used medication at 12 months. Average symptom free duration after the procedure was 7.8 months (range, 1 to 12 months). Two patients were treated surgically. Only two minor complications were noted; transient ptosis with Horner's syndrome and transient causalgia. CONCLUSIONS: Although selective nerve root block for cervical radiculopathy is limited as a definitive treatment, it appears to be useful in terms of providing relief from radicular pain in about 50% of patients at 12 months.

Incidentally Detected Concurrent Lower Thoracic Lesions in Extended Lumbar Spine MRI

STUDY DESIGN: Retrospective study. OBJECTIVES: To evaluate the prevalence and associated factors of the concurrent lower thoracic lesions in patients who have a lumbar spine disease, using the extended lumbar MRI. SUMMARY OF LITERATURE REVIEW: There are no studies regarding the concurrent thoracic lesions with lumbar disease. MATERIALS AND METHODS: All the patients, who had visited the out-patient department (OPD) of orthopaedic surgery in our hospital and underwent lumbar spine MRI, were studied during 1 year. Totally, 750 patients were included. The extended lumbar spine MRI contained additional extended T2-weighted sagittal images that cover the lower thoracic vertebrae with 35 centimeters long. We analyzed the highest observable level, characteristics of detected thoracic lesions. Those lesions were classified according to the severity of compression of the spinal cord and investigation for associated factors of patients. Also, the times for additional tests were measured. RESULTS: Additional tests were able to observe up to the 7th thoracic vertebrae. In 257 cases (34.3%), the lower thoracic lesions were detected and increased with aging (p<0.001). A total of 48 patients (6%) had the lesion compressing the spinal cord and 28 patients needed further evaluation for the lower thoracic lesion. Further, 2 cases were treated surgically for lower thoracic lesions. Scanning extra time for additional test were 3 minutes. CONCLUSIONS: The prevalence of lower thoracic lesions accompanied with the lumbar disease was 34% in this study. Therefore, additional extended lumbar spine MRI is needed to check possible concurrent lesions in the lower thoracic spine.

The Effect of Sacral Alar Screw on Long-level Fusion Including Lumbosacral Segment

STUDY DESIGN: This is a retrospective study. OBJECTIVES: To evaluated the clinical and radiological effectiveness of sacral alar screws for augmentation of S1 pedicle screws in long-level fusion including L5-S1 segment. SUMMARY OF LITERATURE REVIEW: The fusion rates of lumbosacral junction in long-level fusion are various when S1 pedicle screws are used without augmentation. But, reports of sacral alar screw augmentation are rare. MATERIAL AND METHODS: From 1996 to 2005, 63 patients performed more than two-level fusion including lumbosacral junction were reviewed. 47 patients underwent lumbosacral fusion with S1 pedicle screws only (S1 group), and 16 patients with sacral alar screws augmentation in addition to S1 pedicle screws (S1-2 group). Radiologically, bony union, halo sign, and breakage of implants were evaluated. Clinically, complications associated with screw placement and general complications were evaluated. RESULTS: Bony union was obtained in 56 cases(89%) at postoperative 4.3 months. Nonunion was observed in 7 cases(11%, S1 group:5, S1-2 group:2). Loosening of S1 pedicle screw was observed in 32 cases(89%) of S1 group and in 4 cases(25%) of S1-2 group. It showed statistical significance between two groups. Sacral alar screw loosening occurred in 8 cases(50%) of S1-2 group. Metal breakage was developed in 2 cases of S1 group without nonunion or loosening. Postoperative infection occurred in 7 cases(11%, S1 group:5, S1-2 group:2). CONCLUSIONS: Sacral alar screw augmentation was effective on protecting the loosening of S1 pedicle screw. Additional sacral alar screw can improve the rate of fusion for lumbosacral junction despite no statistical significance.

Cervical Facet Cyst Causing Progressive Paraplegia: A Case Report and Review of Literature

STUDY DESIGN: A case report and literature review. OBJECTIVES: To report a patient with a cervical facet cyst causing progressive paraplegia, and to review the clinical features, treatment and outcomes of a cervical facetal cyst. SUMMARY OF LITERATURE REVIEW: Extradural intraspinal synovial cysts of the cervical spine are quite rare. They typically occur in the cervical region at the C1-C2 junction or in the space adjacent to the facet joints in the lower cervical spine, and show similar clinical features to the intervertebral disc protrusion. MATERIALS AND METHODS: This article reports a case of a male patient, 64 years old, who presented with a 2 day history of numbness below the nipple and progressive paraplegia. A physical examination at admission revealed a wheelchair ambulatory state due to a motor deficit (motor grade good) below both hip flexors. Magnetic resonance imaging of the cervical spine showed an extradural lesion with a left lateral extension between C7 and T1, causing spinal cord compression. The patient underwent a hemi-laminectomy of C7 and complete cyst excision through the posterior approach. His motor power improved to almost normal. RESULTS: The patient showed good recovery of myelopathy, and he was able to walk with a cane 3 months after surgery. A 1 year follow-up did not reveal any recurrence or new neurological conditions. CONCLUSION: Cervical facet cysts are rare lesions that are occasionally signaled by progressive paraplegia but can be treated successfully by a surgical excision.

A Comparative Study of the Anterior Cervical Fusion with Harms Cage versus Iliac Bone Block: Clinical and Radiological Outcomes

STUDY DESIGN: A retrospective study. OBJECTIVES: To evaluate the clinical and radiological outcomes of anterior cervical fusion within Harms cage versus an iliac bone block graft. SUMMARY OF LITERATURE REVIEW: There is no current consensus regarding the optimal material for anterior cervical fusion. MATERIALS AND METHODS: This was a single-center study of 107 patients who either underwent anterior cervical fusion with an iliac bone block graft (n=56; group A) or a cancellous bone graft within the cervical Harms titanium cage (n=51; group B). Anterior plating occurred in all cases. Clinical outcomes and complications were evaluated using Visual Analogue Scale (VAS) scores and Odom's Criteria. Radiological outcomes were evaluated by the height of vertebral bodies, sagittal lordosis, the rate of bony union, and the subsidence of cage. RESULTS: The VAS of donor site pain was significantly higher in group A than in group B at the final follow-up. Sagittal lordosis was increased in both groups, but was significantly higher in group B than group A. The rate of bony union was 95% and 91% for both groups 6 months after surgery and reached 100% for both groups at the final follow-up. In terms of cage subsidence, the highest point of subsidence was at the inferior and posterior aspect of the cage and the average amount of subsidence was approximately 1.3 mm at final follow-up. CONCLUSIONS: Anterior cervical fusion using a cancellous bone graft within Harms titanium cage is a good method for anterior cervical fusion with iliac bone block.

Radiographic Analysis of Atlantoaxial Fusion for Atlantoaxial Instability: Comparison of Posterior wiring, Transarticular screw, Posterior screw-rod fixation

STUDY DESIGN: This is a retrospective study. OBJECTIVES: We wanted to clarify the association between the position of the atlantoaxial fusion angle and the change of the subaxial cervical spine alignment (SCA) and the reduction loss after atlantoaxial fusion (AAF) using the posterior wiring technique (PWT), transarticular screw fixation (TAF) and posterior screw-rod fixation (PSR) for treating atlantoaxial instability (AAI). SUMMARY OF LITERATURE REVIEW: There are not many studies on the change of the SCA and the reduction loss after AAF. MATERIALS AND METHODS: Thirty five patients underwent AAF for AAI from 1986 to 2008. The mean follow-up period was 59.5 months. The surgical techniques were divided into three groups, that is, PWT: 17 patients, TAS: 10 and PSR: 8. The causes of instability were transverse ligament rupture in 12 patients, rheumatoid arthritis in 11, Os odontoideum in 6 and nonunion of an odontoid fracture in 6. Plain radiographs were used to assess the atlanto-dental interval, the posterior arch-lamina angle, the change of the SCA and the time of fusion. RESULTS: Fusion was achieved in all the patients within 3.5 months (range: 3-5 months). The radiologic findings in the 5 PWT patients showed a reduction loss and 3 patients showed subaxial cervical kyphosis (SCK). The TAS group had no reduction loss or SCK. The PSR group had no reduction loss and one patient showed SCK. A statistically significant reduction loss and SCK occurred in the group in which there was a posterior arch-laminar angle greater than 10 degrees before and after surgery. CONCLUSIONS: For the treatment of AAI, the position of the AAF is associated with the change of the postoperative SCA. The preoperative lodortic position of C1-2 should be maintained to prevent the change of the SCA.

The Influence of Cervical Spondylosis to Acute Cervical Spinal Cord Injury

STUDY DESIGN: A retrospective study OBJECTIVES: To examine the influence of cervical spondylosis on an acute cervical spinal cord injury. SUMMARY OF LITERATURE REVIEW: There are no reports on the relationship between cervical spondylosis and acute cervical spinal cord injuries. MATERIALS AND METHODS: Twenty six patients who underwent operative treatment for acute cervical injuries with spinal cord injury were evaluated. The mean age and follow-up period was 58 years and 2.2 years, respectively. The evaluation was performed by examining the causes of the injuries, and the classification of fractures according to the presence of cervical spondylosis. This study compared the degrees of postoperative neurological recovery with motor index score in the groups with and without cervical spondylosis. RESULTS: Cervical cord injuries were more prevalent in the group 60 years and older; 17 cases vs. 9 cases in the group under 60 years. Eleven (65%) and 6 (35%) cases in the group 60 years and older had sustained a high and low energy injury, respectively. In contrast, mostly high energy injuries (8 in 9 cases) were encountered in the group under 60 years of age. A low energy injury could cause a acute cervical cord injury in the group 60 years and older, who also had cervical spondylosis. In those cases, previous cervical spondylosis might be one of the etiologic factors. CONCLUSIONS: The cases with cervical spondylosis in the group 60 years and older tended to show incomplete cord injury and good postoperative neurological recovery when they had sustained cervical cord injuries.

Metastatic Osteosarcoma to the Prostate: A Case Report

The most common site for the metastasis of osteosarcoma is the lung, and other sites of metastases include the bone, lymph node, pleura and liver. Although unusual extrapulmonary metastases have been reported with the improvement of the therapeutic results for the primary lesions, they are exceptionally rare. We report here on a case of prostatic metastasis of an osteosarcoma of the proximal tibia, and this developed seven years after successful resection, and four years after resection of a pulmonary metastasis. Radical prostatectomy was performed, and histological examination demonstrated metastatic osteosarcoma. To the best of our knowledge, this is the first case of prostatic metastasis of osteosarcoma in the medical literature.

Avascular Necrosis after Operative Treatment for Fracture and Dislocations of the Talar Neck / 대한족부족관절학회지

PURPOSE: To evaluate the incidence of avascular necrosis (AVN), prognostic reliability of the Hawkins sign, and clinical outcomes after operative treatment of fracture and dislocations of the talar neck. MATERIALS AND METHODS: We analysed 16 patients with fracture and dislocations of the talar neck which were treated by open reduction and internal fixation and followed up for more than 2 years. The postoperative radiographs were examined for Hawkins sign and avascular necrosis was confirmed by bone scan. The assessment of clinical results was based on the Hawkins scoring system. RESULTS: AVN was occurred in 2 of 16 cases (12.5%) only in type III. Hawkins sign was found 11 of 16 cases (68.8%), which included 8 cases in type II, 2 cases in type III and 1 case in type IV. The Hawkins sign was not observed in two cases with AVN. In contrast, only 2 of the 5 cases with a negative Hawkins sign developed AVN. According to Hawkins scoring system, 4 patients (25.0%) was in excellent, 7 patients (43.8%) in good, 4 patients (25.0%) in fair and 1 patient (6.3%) in poor. CONCLUSION: Incidence of AVN after operative treatment of fracture and dislocations of the talar neck was lower than that of previous reports. Hawkins sign had a high prognostic reliability, but absence of Hawkins' sign should not be considered a totally reliable indicator of development of avascular necrosis.