Risk Factors for Cervical Disc Arthroplasty Subsidence with Bryan Disc-A Retrospective Observational Analysis.

Background: Cervical disc arthroplasty (CDA) is currently used instead of fusion to preserve cervical spine motion. Cervical implant subsidence is a potential complication after CDA. Methods: Radiological measurements were recorded via patient anteroposterior and lateral radiographs in the neutral position. Subsidence was defined as a decrease of 3 mm or more in functional spinal unit height (FSUH) from which was measured on a post-operative (OP) radiograph. Results: This study included 104 patients who underwent 153 CDA levels with the Bryan Disc. Approximately one-quarter of the implants (22.9%) showed subsidence. Binary logistic regression analysis indicated that pre-OP mean disc height (DH) was identified as an independent risk factor for subsidence in multivariate analysis (0.151, 95% Confidence Interval 0-0.073, p = 0.018). Receiver operating characteristic curve analysis (area under the curve = 0.852, sensitivity 84.7%, specificity 77.1%) revealed a cut-off value of 4.48 mm for pre-OP Mean-DH in the risk for implant subsidence. Conclusions: In this study, the subsidence rate significantly increased when the implants were oversized beyond a pre-OP Mean-DH of approximately >4 mm. Moreover, the implant subsidence incidence was higher than that reported in previous studies. This is possibly due to endplate over-preparation or disc space over-distraction during placement at the same height as the Bryan Disc (8.5 mm).

Incidence and risk factors of heterotopic ossification after cervical Baguera C disc arthroplasty.

OBJECTIVE: This retrospective study was designed to evaluate the incidence and predisposing factors of heterotopic ossification (HO) after cervical disc arthroplasty (CDA) with a specific implant at 1 and 2 levels, and to investigate the biomechanical effects related to HO. The study goal was to identify ways to reduce the likelihood of HO formation after surgery. METHODS: The study included patients who underwent only 1- or 2-level CDA with the Baguera C disc between November 2014 and December 2021 at a single medical center. All patients were operated on by the same neurosurgeon. The surgical indication included 1-level or 2-level disc herniation between C3 and C7 with radiculopathy, myelopathy, or both, with minimal spondylosis. The various factors were assessed by evaluating plain radiographs and cervical CT scans. The presence of HO was evaluated at different intervals postsurgery, and HO severity was graded using the McAfee classification. RESULTS: Of 107 patients who underwent CDA, 47 (43.9%) had HO at 63 of 171 levels (36.8%). Most cases with HO were grade 1, and no grade 4 was observed. Statistically significant risk factors for HO were the length of endplate coverage ratio and inferior anterior residual exposed endplate (AREE); sex, age, implant height and width, shell angle, and pre- and postoperative functional spinal unit (FSU) angle were not significant. More AREE and greater kyphotic postoperative FSU angle in the flexion position were significant factors differentiating HO grades 0 and 1 from grades 2 and 3. Furthermore, the non-HO group showed a trend of higher range of motion at any postoperative time compared to the HO group, especially at 1 month after surgery. CONCLUSIONS: The HO incidence after CDA was correlated with the residual length of endplate coverage and inferior AREE. Additionally, the AREE and kyphotic postoperative FSU angle in the flexion position were associated with HO grade progression. Patients with HO also showed a trend of lower range of motion at 1 month after surgery. Using an adequately sized implant and encouraging neck motion may help prevent HO development and progression.

Cervical Conjoined Nerve Root During Posterior Percutaneous Endoscopic Cervical Diskectomy.

Cervical conjoined nerve root is rare, and medical imaging, such as magnetic resonance imaging and computed tomography, cannot give an accurate preoperative diagnosis.1 Treatment of cervical radiculopathy with root anomaly can be challenging. We report here a case of cervical conjoined nerve root with a 2-dimensional video. A 41-year-old woman without systemic disease presented with a 2-month history of neck and bilateral shoulder pain, upper back tightness, and left upper limb painful numbness, especially of the first to third fingers. The visual analog scale scores of the neck and left upper limb were 4 and 8, respectively. The Neck Disability Index was 26. The diagnosis of retrolisthesis at C5-C6 and cervical disk herniation with severe neuroforaminal narrowing at the left C5-C6 and C6-C7 levels were made with radiographs and magnetic resonance imaging. Posterior percutaneous endoscopic cervical diskectomy at the left C5-C6 and C6-C7 levels via an interlaminar shoulder approach was performed. During operation, a left-sided conjoined nerve root at the C6-C7 level was found (Video 1). Upon removal of a calcified disk and osteophytes at the C6-C7 level, the dura was torn slightly with traction without nerve root exposure or cerebrospinal fluid leakage. The 3-month postoperative follow-up visual analog scale scores of the neck and left upper limb were 0 and 0, respectively. The 3-month postoperative follow-up Neck Disability Index was 1. Posterior percutaneous endoscopic cervical diskectomy has become a favored treatment for cervical disk herniation because it offers sufficient decompression, smaller incisions, minimal blood loss, shorter hospital stay, and less postoperative pain.2,3 Nonetheless, if unexpected variation of the nerve root is noted during decompressive procedures, iatrogenic nerve root injury is a risk. Seven cases of cervical nerve root anomalies have been reported; all were found during posterior cervical surgery, which may indicate that the posterior approach provides better visualization of nerve root variants, especially in endoscopic surgery.4.

Advances in surgical treatment for atlantoaxial instability focusing on rheumatoid arthritis: Analysis of a series of 67 patients.

AIM: An estimated 88% of rheumatoid arthritis (RA) patients experience various degrees of cervical spine involvement. The excessive movement of the atlantoaxial joint, which connects the occiput to the upper cervical spine, results in atlantoaxial instability (AAI). AAI stabilization is usually achieved by C1 lateral mass-to-C2 pedicle screw-rod fixation (LC1-PC2 fixation), which is technically challenging in RA patients who often show destructive changes in anatomical structures. This study aimed to analyze the clinical results and operative experiences of C1-C2 surgery, with emphasis on the advancement of image-guided surgery and augmented reality (AR) assisted navigation. METHODS: We presented our two decades of experience in the surgical management of AAI from April 2004 to November 2022. RESULTS: We have performed surgery on 67 patients with AAI, including 21 traumatic odontoid fractures, 20 degenerative osteoarthritis, 11 inflammatory diseases of RA, 5 congenital anomalies of the os odontoideum, 2 unknown etiologies, 2 movement disorders, 2 previous implant failures, 2 osteomyelitis, 1 ankylosing spondylitis, and 1 tumor. Beginning in 2007, we performed LC1-PC2 fixation under C-arm fluoroscopy. As part of the progress in spinal surgery, since 2011 we used surgical navigation from presurgical planning to intraoperative navigation, using the preoperative computed tomography (CT) -based image-guided BrainLab navigation system. In 2021, we began using intraoperative CT scan and microscope-based AR navigation. CONCLUSION: The technical complexities of C1-C2 surgery can be mitigated by CT-based image-guided surgery and microscope-based AR navigation, to improve accuracy in screw placement and overall clinical outcomes, particularly in RA patients with AAI.

Pseudoaneurysm formation of segmental artery with retroperitoneal hematoma after percutaneous transpedicular screws insertion.

Vascular injury is one of the potential complications of percutaneous transpedicular screws fixation. Carefully review the vascular anatomy preoperatively is important. Once unexpected low blood pressure or anemia occurs, vascular injury should be taken into consideration.

Anterior Bone Loss after Cervical Baguera C Disc versus Bryan Disc Arthroplasty.

Objectives: The objectives of this study were to identify the risk factors and incidence of anterior bone loss (ABL) after Baguera C cervical disc arthroplasty (CDA) and identify whether design differences in artificial discs affect ABL. Methods: In this retrospective radiological review of patients who underwent single-level Baguera C CDA in a medical center, the extent of ABL and the following radiological parameters were recorded: global and segmental alignment angle, lordotic angle (or functional spinal unit angle), shell angle, global range of motion (ROM), and ROM of the index level. ABL at the index level was grade 0-2. Grade 0 was defined as no remodeling, grade 1 as spur disappearance or mild change in body contour, and grade 2 as obvious bone regression with Baguera C Disc exposure. Results: Combining grade 1 and grade 2, ABL was found in 56 upper adjacent vertebrae and 52 lower adjacent vertebrae of the 77 patients. Only 18 patients (23.4%) had no ABL. Shell angle differed significantly between ABL grades of both the upper and lower adjacent level: 0.0° in grade 0 and 1 ABL vs. 2.0° in grade 2 ABL of the upper adjacent level (p < 0.05); and 0.0° in grade 0 and 1 ABL vs. 3.5° in grade 2 ABL of the lower adjacent level (p < 0.05). A female predominance of ABL was found. Hybrid surgery and artificial disc size were also related to ABL. Conclusions: ABL is more common in Baguera C Disc arthroplasty than Bryan Disc arthroplasty. Larger shell angle was related to ABL after CDA with Baguera C Discs, which may indicate that shell angle is pivotal in determining the incidence of ABL after CDA. Females had more ABL with Baguera C Disc arthroplasty; this might be related to shorter endplate lengths as well as a smaller endplate-implant mismatch.

Cell Therapy with Human Dermal Fibroblasts Enhances Intervertebral Disk Repair and Decreases Inflammation in the Rabbit Model.

Study Design Pilot study using the rabbit model. Objective Low back pain is often associated with disk degeneration. Cell therapy for degenerating disks may promote tissue regeneration and repair. Human dermal fibroblasts, obtained from the patient's skin tissue or donated tissue, may be a promising cell therapy option for degenerating disks. The objective of these studies is to determine the effects of intradiscal transplantation of neonatal human dermal fibroblasts (nHDFs) on intervertebral disk (IVD) degeneration by measuring disk height, magnetic resonance imaging (MRI) signal intensity, gene expression, and collagen immunostaining. Methods New Zealand white rabbits (n = 16) received an annular puncture to induce disk degeneration and were treated with nHDFs or saline 4 weeks later. At 2 and 8 weeks post-treatment, X-ray and MRI images were obtained. IVDs were isolated and examined for changes in collagen staining and gene expression. Results In the nHDF-treated group, there was a 10% increase in the disk height index after 8 weeks of treatment (p ≤ 0.05), and there was no significant difference in the saline-treated group. When compared with the saline-treated disks, disks treated with nHDFs showed reduced expression of inflammatory markers, a higher ratio of collagen type II over collagen type I gene expression, and more intense immunohistochemical staining for both collagen types I and II. Conclusions Human dermal fibroblast introduction into the disk reduced inflammation and promoted tissue rich in both type I and type II collagens. The results of this study suggest that nHDFs would be a feasible cell therapy option for disk degeneration.

The Surgical Treatment Principles of Atlantoaxial Instability Focusing on Rheumatoid Arthritis.

OBJECT: This retrospective review was conducted to determine the surgical treatment principle for rheumatoid arthritis (RA) patients with atlantoaxial instability (AAI). METHODS: Thirteen patients with AAI, including 5 RA patients, received preoperative computed tomography- (CT-) based image-guided navigation system (IGS) in C1 lateral mass-C2 pedicle screw-rod system fixation (LC1-PC2 fixation). These 13 patients were analyzed for 52 screws inserted into C1 and C2. We defined these patients as non-RA group (8 patients, 32 screws) and RA group (5 patients, 20 screws). The neurological status for RA group was evaluated using the Ranawat classification. The causes of AAI, surgical indications, complications, surgical method revolution, and CT-based navigation application are discussed. RESULTS: None of the 13 patients expressed neurological function deterioration. The non-RA group screw accuracy was 100%. In the RA group, 1 RA patient developed left C2 screw loosening at 1(+) months after operation due to screw malposition. The screw accuracy for this group was 95%. CONCLUSIONS: Higher intraoperative surgical complication rate was described in RA patients. Preoperative CT-based IGS in LC1-PC2 fixation can provide good neurological function and screw accuracy results. However, for higher screw accuracy in RA patients, intraoperative CT-based IGS application may be considered.

Nerve growth factor increases MMP9 activity in annulus fibrosus cells by upregulating lipocalin 2 expression.

PURPOSE: Nerve growth factor (NGF) expression and activity is important in chronic lower back pain but may also act as a pro-catabolic factor in the pathogenesis of intervertebral disc (IVD) degeneration. Lipocalin 2 (Lcn2) expression in IVD was upregulated by NGF stimulation in our previous study. The current study was undertaken to identify potential mechanisms of the latter effect including potential interactions between Lcn2 and matrix metalloproteinase 9 (MMP9). METHODS: Rat annulus fibrosus (AF) cells were stimulated by NGF and subjected to microarray analysis, subsequent real-time PCR, western immunoblotting, and immunofluorescence. Cells were treated with NGF in the absence or presence of the NGF inhibitor Ro 08-2750. Zymography and functional MMP9 assays were used to determine MMP9 activity, whilst the dimethyl-methylene blue assay was used to quantify the release of glycosaminoglycans (GAGs) reflecting catabolic effects following NGF treatment. Immunoprecipitation with immunoblotting was used to identify interactions between MMP9 and Lcn2. RESULTS: Increased expression of Lcn2 gene and protein following NGF stimulation was confirmed by microarray analysis, real-time PCR, western blot and immunofluorescence. Zymography showed that NGF enhanced 125-kDa gelatinase activity, identified as a Lcn2/MMP9 complex by immunoprecipitation and immunoblotting. Functional assays showed increased MMP9 activity and GAG release in the presence of NGF. The effects of NGF were neutralized by the presence of Ro 08-2750. CONCLUSIONS: NGF upregulates Lcn2 expression and increases MMP9 activity in AF cells; processes which are likely to potentiate degeneration of AF tissue in vivo. Anti-NGF treatment may have benefit for management of pain relief and slowing down progression of AF tissue degeneration.

Risk factors for subsidence in anterior cervical fusion with stand-alone polyetheretherketone (PEEK) cages: a review of 82 cases and 182 levels.

INTRODUCTION: To determine risk factors for subsidence in patients treated with anterior cervical discectomy and fusion (ACDF) and stand-alone polyetheretherketone (PEEK) cages. MATERIALS AND METHODS: Records of patients with degenerative spondylosis or traumatic disc herniation resulting in radiculopathy or myelopathy between C2 and C7 who underwent ACDF with stand-alone PEEK cages were retrospectively reviewed. Cages were filled with autogenous cancellous bone harvested from iliac crest or hydroxyapatite. Subsidence was defined as a decrease of 3 mm or more of anterior or posterior disc height from that measured on the postoperative radiograph. Eighty-two patients (32 males, 50 females; 182 treatment levels) were included in the analysis. RESULTS: Most patients had 1-2 treatment levels (62.2 %), and 37.8 % had 3-4 treatment levels. Treatment levels were from C2-7. Of the 82 patients, cage subsidence occurred in 31 patients, and at 39 treatment levels. Multivariable analysis showed that subsidence was more likely to occur in patients with more than two treatment levels, and more likely to occur at treatment levels C5-7 than at levels C2-5. Subsidence was not associated with postoperative alignment change but associated with more disc height change (relatively oversized cage). CONCLUSION: Subsidence is associated with a greater number of treatment levels, treatment at C5-7 and relatively oversized cage use.

Nerve growth factor promotes expression of novel genes in intervertebral disc cells that regulate tissue degradation: Laboratory investigation.

OBJECT: Increased neurotrophin activity in degenerative intervertebral discs (IVDs) is one potential cause of chronic low-back pain (LBP). The aim of the study was to assess if nerve growth factor (NGF) might alter gene expression of IVD cells and contribute to disc degeneration by enhancing expression or activity of factors that cause breakdown of IVD matrix. METHODS: Rat-tail IVD cells were stimulated by NGF and subjected to microarray analysis. Real-time polymerase chain reaction, Western blotting, and immunocytochemistry of rat and human IVD cells and tissues treated with NGF in vitro in the absence or presence of the NGF inhibitor Ro 08-2750 were used to confirm findings of the microarray studies. Phosphorylation of mitogen-activated protein kinase (MAPK) was used to identify cell signaling pathways involved in NGF stimulation in the absence or presence of Ro 08-2750. RESULTS: Microarray analysis demonstrated increased expression of chitinase 3-like 1 (Chi3l1), lipocalin 2 (Lcn2), and matrix metalloproteinase-3 (Mmp3) following NGF stimulation of rat IVD cells in vitro. Increased gene expression was confirmed by real-time polymerase chain reaction with a relative increase in the Mmp/Timp ratio. Increased expression of Chi3l1, Lcn2, and Mmp3 following NGF stimulation was also demonstrated in rat cells and human tissue in vitro. Effects of NGF on protein expression were blocked by an NGF inhibitor and appear to function through the extracellular-regulation kinase 1/2 (ERK1/2) MAPK pathway. CONCLUSIONS: Nerve growth factor has potential effects on matrix turnover activity and influences the catabolic/anabolic balance of IVD cells in an adverse way that may potentiate IVD degeneration. Anti-NGF treatment might be beneficial to ameliorate progressive tissue breakdown in IVD degeneration and may lead to pain relief.

Application of intraoperative computed tomography with or without navigation system in surgical correction of spinal deformity: a preliminary result of 59 consecutive human cases.

STUDY DESIGN: A retrospective analysis of patients undergoing spinal deformity correction surgery by the assistance of intraoperative computed tomography (iCT) with or without navigation system. OBJECTIVE: To share our preliminary experience and analysis of the iCT navigation system applied to spinal deformity surgery. SUMMARY OF BACKGROUND DATA: The iCT navigation system has been shown to improve accuracy and safety in posterior instrumentation. It not only decreased the operation time but also prevented excessive radiation exposure to the medical staff. To date, there are only few reports about the application of the iCT navigation system in spinal deformity surgery. METHODS: From April 2009 to September 2010, 59 patients who had a diagnosis of scoliosis, kyphosis, or scoliokyphosis and underwent iCT-assisted surgical correction were included. Without randomization, 28 patients were operated with the iCT-navigation system, and the other 31 patients were operated with standard procedure under iCT assistance. The detailed procedures, preoperative and intraoperative images were illustrated. The accuracy of screw placement, time for screw insertion, postoperative correction rate, and iCT scanning data were analyzed. RESULTS: There were significant differences between 2 groups in (1) the preoperative Cobb angle (76.2° and 62.6° in the navigation and non-navigation groups), (2) the accuracy and the revision rate of thoracic pedicle screws and total pedicle screws, and (3) the average screw insertion time. The breach rate and the revision rate of thoracic pedicle screws and total pedicle screws were significantly lower and the average screw insertion time was significantly lesser in the navigation group than in the non-navigation group. There were no statistically significant difference in (1) the breach rate and the revision rate of lumbar pedicle screws, (2) the mean iCT scanning time and time-out, (3) the mean number of fusion segments, (4) the mean number of iCT scans, and (5) the postoperative correction rate. Complications were encountered in 2 patients in the non-navigation group but none in the navigation group. There was no reoperation due to implant malposition in both groups. CONCLUSION: The iCT navigation system provides desirable accuracy of posterior spinal instrumentation for patients during surgical correction of spinal deformity without radiation exposure to the medical staff, especially in thoracic spine instrumentation. Meanwhile, the iCT in itself is an effective means of assessing complex instrumentation of the spinal deformity.

Endoscopic discectomy of L5-S1 disc herniation via an interlaminar approach: Prospective controlled study under local and general anesthesia.

BACKGROUND: Open discectomy remains the standard method for treatment of lumbar disc herniation, but can traumatize spinal structure and leaves symptomatic epidural scarring in more than 10% of cases. The usual transforaminal approach may be associated with difficulty reaching the epidural space due to anatomical peculiarities at the L5-S1 level. The endoscopic interlaminar approach can provide a direct pathway for decompression of disc herniation at the L5-S1 level. This study aimed to evaluate the clinical results of endoscopic interlaminar lumbar discectomy at the L5-S1 level and compare the technique feasibility, safety, and efficacy under local and general anesthesia (LA and GA, respectively). METHODS: One hundred twenty-three patients with L5-S1 disc herniation underwent endoscopic interlaminar lumbar discectomy from October 2006 to June 2009 by two spine surgeons using different anesthesia preferences in two medical centers. Visual analog scale (VAS) scores for back pain and leg pain and Oswestry Disability Index (ODI) sores were recorded preoperatively, and at 3, 6, and 12 months postoperatively. Results were compared to evaluate the technique feasibility, safety, and efficacy under LA and GA. RESULTS: VAS scores for back pain and leg pain and ODI revealed statistically significant improvement when they were compared with preoperative values. Mean hospital stay was statistically shorter in the LA group. Complications included one case of dural tear with rootlet injury and three cases of recurrence within 1 month who subsequently required open surgery or endoscopic interlaminar lumbar discectomy. There were no medical or infectious complications in either group. CONCLUSION: Disc herniation at the L5-S1 level can be adequately treated endoscopically with an interlaminar approach. GA and LA are both effective for this procedure. However, LA is better than GA in our opinion.

Intradiscal electrothermal therapy in the treatment of chronic low back pain: experience with 93 patients.

BACKGROUND: Low back pain (LBP) has become a main cause of absenteeism and disability in industrialized societies. Chronic LBP is an important health issue in modern countries. Discogenic LBP is one of the causes of chronic low back pain. The management of chronic discogenic LBP has been limited to either conservative treatment or operative treatment. Intradiscal electrothermal therapy (IDET) is now being performed as an alternative treatment. METHODS: Ninety-three consecutive patients undergoing IDET at 134 disc levels from October 2004 to January 2007 were prospectively evaluated. All patients had discogenic disease with chronic LBP, as determined by clinical features, physical examination and image studies, and had failed to improve with conservative treatment for at least 6 months. Follow-up period was from 1 week to 3 or more years postoperatively. RESULTS: There were 50 male and 43 female patients, with a mean age of 46.07 years (range, 21-65 years). The results were classified as symptom free (100% improvement), better (≥50% improvement), slightly better (<50% improvement), unchanged and aggravated. Eighty-nine patients were followed up in the first week; of them, 77 (86.52%) patients had improvement (4, symptom free; 45, better; and 28, slightly better). The improvement rate gradually decreased to 80.90% in 1 year; and 73.91%, in 3 years. CONCLUSIONS: In conclusion, IDET offers a safe, minimally invasive therapy option for carefully selected patients with chronic discogenic LBP who have not responded to conservative treatment. Although IDET appears to provide intermediate-term relief of pain, further studies with long-term follow-up are necessary.

Percutaneous pulsed radiofrequency in the treatment of cervical and lumbar radicular pain.

BACKGROUND: Previous reports of the efficacy of percutaneous pulsed radiofrequency have been confounded by fewer case numbers, poor patient selection, and limited data on cervical or lumbar radicular pain. We used percutaneous pulsed radiofrequency for cervical and lumbar radicular pain, and the study has more than 100 cases for the analysis of the efficacy of percutaneous pulsed radiofrequency. METHODS: We collected 154 cases of patients with lumbar or cervical radicular pain due to a herniated intervertebral disk or previous failed surgery. They underwent pulsed radiofrequency therapy in 2 to 4 spinal levels unilaterally. Follow-up period was from 1 week to 1 year postoperatively. RESULTS: Twenty-six (53.06%) of 49 patients and 59 (50.86%) of 116 patients after cervical and lumbar pulsed radiofrequency stimulation, respectively, had an initial improvement of 50% or more in the first week of follow-up. Twenty-seven (55.10%) of 49 patients and 52 (44.83%) of 116 patients after cervical and lumbar pulsed radiofrequency stimulation, respectively, had pain relief of 50% or more at the follow-up period of 3 months. In the analysis of patients with pain relief of 50% or more for at least 1 month, the most effective period was during postoperation 1 month later. No complication was found among these patients. CONCLUSIONS: The results of this retrospective analysis showed that the application of pulsed radiofrequency is a safe and useful intervention for cervical and lumbar radicular pain. The satisfactory pain relief obtained by most of our patients justifies the start of this study for at least 6 months. Although pulsed radiofrequency appears to provide intermediate-term relief of pain, further studies with long-term follow-up are necessary.

Successful treatment of extended epidural abscess and long segment osteomyelitis: a case report and review of the literature.

BACKGROUND: Spinal osteomyelitis and epidural abscess are complicated medical conditions. Diagnosis is often delayed because of cormorbidity. The time of instrumentation is still controversial. However, there is no doubting the indication of spinal hardware implantation when spinal fusion is needed. Long segment osteomyelitis and extended epidural abscess are rare. The treatment is challenging for neurosurgeons. We report a case of extended epidural abscesses and long segments of osteomyelitis. METHODS: One-stage meticulous debridement, anterior cervical corpectomies, and spinal fusion with mesh cage and titanium plate were performed on the patient. Hyperbaric oxygenation and 6 weeks of intravenous antibiotics were prescribed as adjuvant therapy. RESULTS: Both clinical presentations and imaging studies showed a good response to the treatment. The patient returned to his life 3 months later. CONCLUSIONS: This case illustrates that spinal instrumentation is not an absolute contraindication in the presence of epidural abscesses and vertebral osteomyelitis. Combined surgical debridement at a critical level, with adjuvant antibiotics and hyperbaric oxygenation, is a safe and effective therapy in those with neurologic deficits, spinal instability, and extended epidural abscess.

"Primary" benign retroperitoneal and intraspinal dumbbell-shaped cystic teratoma: case report.

STUDY DESIGN: A case of unusual dumbbell-shaped cystic teratoma is presented. OBJECTIVES: To investigate and describe an unusual case of retroperitoneal cystic teratoma with spinal invasion in an adult. The image findings, minimally invasive surgical procedures, and clinical outcome were discussed, and the literature was reviewed. SUMMARY OF BACKGROUND DATA: Primary benign cystic teratomas of the retroperitoneum are rare. Extension of these lesions into the spinal canal is more rare. In this report, by presenting a case of cystic teratoma with such extension, the origin of the tumor, and the value of computerized tomography and magnetic resonance imaging (MRI) in the preoperative diagnosis and surgical approach for the extended lesion are discussed. METHODS: The patient was a 24-year-old female who had had low back pain with bilateral sciatica for 2 months. Preoperative computerized tomography and MRI of the thoracic and lumbar spines showed a dumbbell-shaped tumor, with the solid part residing in the right retroperitoneum near the neuroforamen of the L2-L3 spines and the cystic part extending into the spinal canal. By performing right L2-L4 hemilaminectomies with a mini retroperitoneal approach, the tumor was removed en bloc in one stage. RESULTS: Diagnosis of cystic teratoma was confirmed by pathologic examination. The patient recovered well without any neurologic deficits, and recurrence of tumor has not been found for 9 years postoperatively. CONCLUSIONS: Total surgical removal of tumor is an ideal treatment for retroperitoneal and intraspinal dumbbell-shaped cystic teratoma. MRI displays the precise location, morphology, and adjacent structures of the tumor, which provide for better preoperative planning and more complete removal of tumor with less neurologic damage.

Upper thoracic sympathectomy for axillary osmidrosis or bromidrosis.

The difference between axillary osmidrosis (AO) and axillary bromidrosis (AB) is the degree of odor and quantity of sweat, which is associated with selection of therapeutic modality theoretically. Upper thoracic sympathectomy has been used for both diseases but its effect needs to be further evaluated with more clinical data. We collected 108 patients with AO or AB treated by upper thoracic sympathectomy from July 1995 to July 2002. Of these patients, 42 suffered AO alone, 17 had AB (AO with axillary hyperhidrosis [AH]), and 49 had AO with palmar hyperhidrosis (PH). Ninety-two patients (183 sides) received anterior subaxillary transthoracic endoscopic sympathectomy (TES) and 17 patients (33 sides) received posterior percutaneous thoracic phenol sympathicolysis (PTPS). The levels of sympathectomy or sympathicolysis were T3-4 for AO and AB, and T2-4 for AO with PH. Mean follow-up period was 45.2 months (13-97 months). The satisfaction rates of patients were 52.4%, 70.6% and 61.2% for AO, AB and AO with PH, respectively. The rates of patients with improvement and satisfaction were 78.6%, 88.2% and 85.7% for AO, AB, and AO with PH, respectively. These results suggest that upper thoracic sympathectomy may be an acceptable treatment for AB or AO with PH rather than AO only.