Comparison of Skeletal Stability after Le Fort I Osteotomy With Bone Fixation Using Biodegradable and Titanium Systems: A Retrospective Study.

The titanium osteosynthesis system used for fixing bone segments after maxillary osteotomy provides reliable outcomes owing to its biocompatibility and adequate strength. In addition, several studies have evaluated the skeletal stability after maxillary osteotomy with fixation using a biodegradable system. However, the indications for applying a biodegradable system after maxillary osteotomy remain controversial. Therefore, this study aimed to compare the long-term skeletal stability of bone segments after maxillary osteotomy with bone fixation using biodegradable and titanium osteosynthesis systems and to assess the usefulness of a biodegradable osteosynthesis system. Patients who underwent Le Fort I osteotomy of the maxilla to correct jaw deformities between April 2008 and March 2021 were included in this study. A total of 45 patients were included, with 28 in the biodegradable osteosynthesis system group and 17 in the titanium group. Cephalometric and computed tomography analyses were performed to evaluate the skeletal stability of the bone segments after maxillary osteotomy with bone fixation using biodegradable or titanium osteosynthesis systems. The maxillary segment was repositioned anteriorly with a clockwise rotation. Skeletal stability was similar between the biodegradable and titanium osteosynthesis systems. Segmental changes occurred mainly in the first 6 months after surgery, and the segment was completely stable between 6 and 12 months after surgery. This study revealed no significant differences in skeletal stability after maxillary osteotomy between the biodegradable and titanium osteosynthesis systems. However, the findings in this study should be interpreted with caution owing to the small sample size and small amount of maxillary-segment movement.

Molecular insights and the role of 18F-FDG-PET/CT in the diagnosis of spinal gliomas.

BACKGROUND: In recent years, molecular findings on spinal gliomas have become increasingly important. This study aimed to investigate the role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) in the diagnosis of spinal glioma. METHODS: This study included patients diagnosed with spinal cord glioma who underwent 18F-FDG-PET examination at the Department of Neurosurgery, Nagoya University Hospital between January 2016 and November 2023. The gliomas were divided into two groups, high-grade and low-grade, based on pathological and molecular studies. The maximum standardized uptake values (SUVmax) of the tumors were quantified and subsequently represented using receiver operating characteristic (ROC) curves. RESULTS: Eighteen participants were included in this study. Of the participants, seven had high-grade glioma with an SUVmax of 6.76 ± 0.72, and eleven had low-grade glioma with an SUVmax of 4.02 ± 1.78, and a statistically significant difference between the two groups. The ROC curve delineated an SUVmax cutoff value of 5.650, with an area under the curve (AUC) of approximately 0.909. Based on the cutoff value, the results of the diagnostic performance rendered a sensitivity and negative predictive value of 1.0, whereas the specificity and positive predictive value were 0.909 and 0.875, respectively. CONCLUSIONS: The present study shows that 18F-FDG-PET exhibits a markedly sensitive and negative predictive value in the assessment of spinal gliomas. Additionally, these findings have potential implications for the qualitative assessment of spinal gliomas using 18F-FDG-PET/CT. This imaging modality may be useful for making timely treatment decisions in situations where a detailed diagnosis by molecular analysis is not possible.

Comparative Study of Surgical Outcomes of Occipitocervical and Atlantoaxial Fusion for Retro-Odontoid Pseudotumor.

OBJECTIVE: To compare the surgical and radiographic outcomes of occipitocervical fusion (OCF) with those of atlantoaxial fusion (AAF) in patients with cervical myelopathy caused by retroodontoid pseudotumors (ROPs). METHODS: This retrospective, comparative study included 26 patients; 12 underwent occipitocervical fusion (OCF) (group O) and 14 retroodontoid pseudotumor (AAF) (group A) with a minimum 2-year follow-up. Neurologic outcomes were evaluated using the Japanese Orthopedic Association (JOA) score. Radiologic assessment included the maximum anteroposterior (AP) diameter of the anteroposterior-retroodontoid pseudotumor (AP-ROP), C2-7 angle, O-C2 angle, C1-2 angle, atlantodental interval (ADI), range of motion (ROM) of the ADI, C2-C7 sagittal vertical axis (C2-7 SVA), and T1 slope. Global spinal alignments (pelvic incidence [PI] minus lumbar lordosis [LL] [PI-LL], pelvic tilt, sacral slope, and C7 sagittal vertical axis) were also compared between the groups. RESULTS: Both groups had equally good clinical outcomes with equal complication rates. Three patients had a three-level fusion, 5 cases had a four-level fusion, and 4 cases had more than five-level fusion in group O. All cases had a single-level fusion in group A. Surgical time was significantly shorter in group A. AP-ROP was significantly downsized postoperatively in both groups and was more prominent in group O. C2-7 SVA was significantly increased and C2-7A ROM was significantly reduced in group O at the final follow-up. The PI-LL showed a significant increase in group O at the final follow-up. CONCLUSIONS: Although OCF and AAF were similarly effective for cervical myelopathy with ROP, AAF was less invasive, and spinal alignment was better maintained postoperatively in AAF than OCF.

Surgical Outcomes of Common Peroneal Nerve Entrapment Neuropathy Associated with L5 Radiculopathy.

Impingement of the common peroneal nerve, a branch of the L5 nerve root, causes common peroneal nerve entrapment neuropathy (CPNE). Although there are cases of CPNE associated with L5 radiculopathy, surgical intervention's effectiveness remains to be elucidated. This retrospective case-control study aimed to evaluate the efficacy of surgery in patients with CPNE associated with L5 radiculopathy. Twenty-two patients (25 limbs) with surgically treated CPNE between 2015 and 2022 were retrospectively reviewed. The limbs were classified into two groups: group R (limbs of CPNE associated with L5 radiculopathy) and group O (limbs of CPNE without L5 radiculopathy). The durations from onset to surgery, the nerve conduction studies (NCSs), and postoperative improvement rates for motor weakness, pain, and dysesthesia were compared between the groups. Group R included 15 limbs (13 patients), and group O included 10 limbs (9 patients). There were no significant differences in the duration from onset to surgery or abnormal findings of NCS between the two groups. The postoperative improvement rates were 88% and 100% (p = 0.62) for muscle weakness, 87% and 80% (p = 0.53) for pain, and 71% and 56% (p = 0.37) for dysesthesia in group R and group O, respectively, without significant differences between groups. CPNE associated with L5 radiculopathy is common, and the results of the present study showed that the surgical outcomes in such cases were satisfactory and comparable to those in CPNE without L5 radiculopathy.

Comparative Study of Anterior Transvertebral Foraminotomy and Anterior Cervical Discectomy and Fusion for Unilateral Cervical Spondylotic Radiculopathy.

OBJECTIVE: To study the compared surgical and radiographic outcomes of Transvertebral foraminotomy (TVF) with anterior cervical discectomy and fusion (ACDF) in patients with unilateral cervical spondylotic radiculopathy (CSR). METHODS: We performed a retrospective comparative study of 72 consecutive patients with 1- or 2-level CSR treated with ACDF or TVF. 27 patients who underwent TVF (group T) and 45 patients who underwent ACDF (group A) with a minimum 2-year follow-up were enrolled. We evaluated clinical outcomes and radiological assessment. Clinical outcome included Visual analog scale (VAS) scores for axial, arm pain at preoperatively and final follow-up. VAS score for painful swallowing was also evaluated 1 week after surgery. Radiological assessment included C2-7 sagittal Cobb angle (C2-7 CA), range of motion (ROM) of C2-7 CA, the height, angle and ROM of the functional spinal unit (FSU), and tip of the spinous process of the operated segment. We also evaluated the disc height, FSU angle, and ROM of the FSU at the cranial adjacent segment. RESULTS: Both groups had good clinical outcomes. Soft tissue swelling was significantly less prominent in group T than that for group A. VAS scores for painful swallowing is lower in group T without significant difference. The ROM of C2-7 CA, FSU, and spinous processes demonstrated a significant reduction in group A compared with group T.(P < 0.05). Disc height at the cranial adjacent segment was maintained in group T. CONCLUSIONS: TVF is as effective as ACDF for unilateral CSR and preserves whole cervical spine and segmental alignment.

Safety and Validity of Anterior Cervical Disc Replacement for Single-level Cervical Disc Disease: Initial Two-year Follow-up of the Prospective Observational Post-marketing Surveillance Study for Japanese Patients.

Anterior cervical disc replacement (ACDR) using cervical artificial disc (CAD) has the advantage of maintaining the range of motion (ROM) at the surgical level, subsequently reducing the postoperative risk of adjacent disc disease. Following the approval for the clinical use in Japan, a post-marketing surveillance (PMS) study was conducted for two different types of CAD, namely, Mobi-C (metal-on-plastic design) and Prestige LP (metal-on-metal design). The objective of this prospective observational multicenter study was to analyze the first 2-year surgical results of the PMS study of 1-level ACDR in Japan. A total of 54 patients were registered (Mobi-C, n = 24, MC group; Prestige LP, n = 30, PLP group). Preoperative neurological assessment revealed radiculopathy in 31 patients (57.4%) and myelopathy in 15 patients (27.8%). Preoperative radiological assessment classified the disease category as disc herniation in 15 patients (27.8%), osteophyte in 6 patients (11.1%), and both in 33 patients (61.1%). The postoperative follow-up rates at 6 weeks, 6 months, 1 year, and 2 years after ACDR were 92.6%, 87.0%, 83.3%, and 79.6%, respectively. In both groups, patients' neurological condition improved significantly after surgery. Radiographic assessment revealed loss of mobility at the surgical level in 9.5% of patients in the MC group and in 9.1% of patients in the PLP group. No secondary surgeries at the initial surgical level and no serious adverse events were observed in either group. The present results suggest that 1-level ACDR is safe, although medium- to long-term follow-up is mandatory to further verify the validity of ACDR for Japanese patients.

Laminectomy triggers symptomatic growth of spinal schwannoma in a patient with schwannomatosis.

Background: Schwannomatosis (SWN) is genetically similar to neurofibromatosis type 2 (NF2) and represents a NF2 gene mutation. Previous studies have shown that these mutations in both neurons and Schwann cells can lead to the development of schwannomas after nerve crush injuries. Here, we reviewed the potential pathoanatomical mechanisms for the development of a trauma-induced spinal schwannomas in a 55-year-old male with SWN. Case Description: A 49-year-old male had originally undergone a L3-L5 lumbar laminectomy for stenosis; the schwannomas seen on the preoperative magnetic resonance imaging (MRI) were not resected. Now at age 55, he newly presented with low back pain and numbness in the left L5 dermatome, and he was diagnosed with an L4 vertebral level cauda equina tumor on MRI. Following gross-total resection, the histopathological assessment revealed a Ki-67 labeling index 5-10% in hotspots (i.e., slightly higher than the normal range of schwannomas) and a 20% mosaic loss of SMARCB1. Based on these criteria, he was diagnosed as having SWN. Conclusion: In this patient with SWN, compression/physical trauma to nerves of the cauda equina during the L3-L5 laminectomy 6 years ago likely caused the progression of schwannoma.

Radiological Analysis of Minimally Invasive Microscopic Laminectomy for Lumbar Canal Stenosis with a Focus on Multilevel Stenosis and Spondylolisthesis.

OBJECTIVE: We retrospectively compared the radiological and clinical outcomes of two different surgical techniques (lumbar spinous process splitting laminectomy [LSPSL] and unilateral laminotomy for bilateral decompression [ULBD]) to treat lumbar spinal canal stenosis (LCS). METHODS: We performed a retrospective comparative study of 141 consecutive patients with an average age of 70.8 ± 9.4 years who had undergone LSPSL or ULBD for LCS between April 2015 and April 2019. None of the patients had developed remote fractures of the spinous processes using either technique. These cases were divided into 2 groups: group L, 73 patients who had undergone LSPSL from April 2015 to April 2017; and group U, 68 patients who had undergone ULBD from May 2017 to April 2019. The clinical and radiological outcomes and surgical complications at the 1-year postoperative follow-up period were evaluated. RESULTS: We found no significant differences in the operative time between the 2 groups. However, group U had had significantly less blood loss than group L. The facet joints were significantly well preserved in group U. We examined the multilevel and spondylolisthesis cases separately and found that both surgical procedures were equally effective and that the visual analog scale scores for back or leg pain and Japanese Orthopaedic Association scores had significantly improved postoperatively in each group. Group U showed better outcomes in terms of LCS recurrence, with 3 patients in the group L requiring repeat surgery. CONCLUSIONS: We found both ULBD and LSPSL to be safe and effective techniques for LCS, even for patients with spondylolisthesis and multilevel disease. ULBD was superior in terms of recurrence prevention, preservation of the facet joints, and less blood loss.

Piecemeal resection of aggressive vertebral hemangioma using real-time navigation-guided drilling technique.

Vertebral hemangiomas are the most common benign vertebral tumors and are usually asymptomatic. Aggressive subtypes of the tumor, called aggressive VHs (AVHs), can become symptomatic with extraosseous extensions and require surgical removal. We present a case of AVH in a 36-year-old man presenting with low back pain and right leg pain that persisted for three months. Imaging studies showed a Th12 vertebral tumor that extended into the spinal canal and was squeezing the spinal cord. Computed tomography (CT)-guided biopsy indicated vertebral hemangimoa. Following preoperative arterial embolization, piecemeal gross total resection was attained under navigation guidance. He was left with no neurological deficit and remained well at the 12-month postoperative folow-up. Since AVHs are benign tumor, piecemeal removal of the tumor can be selected. However, disadvantage of the approach include difficulty of making decision how much to remove the front part of the vertebral body close to thoracic descending aorta. Furthermore, when the tumor tissue is too hard to curett, manipulation in tight spaces near the spinal cord carries the risk of damaging it. Navigation-guided drill is highly helpful for real-time monitoring of ongoing tumor resection. It enables safely resection of the tumor especially in the anterior cortical surface of the vertebral body and easily resection even hard tumors. This method results in reducing residual tumor and maintaining safety resection.

[Differential Diagnosis between Spinal Degenerative Disorder and Peripheral Nerve Entrapment Disease].

In the surgical treatment of spinal degenerative disorders, neural function improves to some extent upon successful neural decompression. However, we have witnessed cases with poor postoperative results. The causes include surgical procedure issues, such as insufficient decompression of neural tissues and overlooking sites to be decompressed, and neurological misdiagnosis of other causative lesions or multiple lesions. Here, as necessary knowledge for spine surgeons dealing with spinal cord degenerative disorders to prevent poor surgical results, we have discussed the differentiation of peripheral nerve entrapment neuropathy from spinal degenerative disorders. Specifically, we have focused on L5 radiculopathy or common peroneal nerve entrapment disorder and C8 radiculopathy or thoracic outlet syndrome or ulnar nerve entrapment neuropathy, which are difficult to distinguish, and have explained the difference in their neurological symptoms from an anatomical perspective. We have also described the differential diagnosis of drop fingers, which is one of the neurological symptoms, and have mentioned the possibility of diseases managed by neurologists, which neurosurgeons should know about.

Driver Genetic Mutations in Spinal Cord Gliomas Direct the Degree of Functional Impairment in Tumor-Associated Spinal Cord Injury.

Genetic analysis in glioma has been developed recently. Spinal cord glioma is less common than intracranial glioma. Thus, the clinical significance of genetic mutations in spinal cord gliomas remains unclear. Furthermore, because the spinal cord is an important communication channel between the brain and the rest of the body, increased attention should be paid to its functional prognosis. In this study, we investigated the functional prognosis and driver genetic mutations in eight patients with spinal cord gliomas (World Health Organization grade I, three cases; grade II, two cases; grade III/IV, three cases). IDH mutations were detected in all grade II cases and H3F3A mutations were detected in all grade III/IV cases. The functional status of grade I and II gliomas remained unchanged or improved 1 year after surgery, whereas grade III/IV gliomas remained unchanged or deteriorated. Spinal glioma progenitor cells with H3F3A mutations were associated with accelerated tumor-associated spinal cord injury, which led to functional impairment. Conversely, the presence of IDH mutations, which are rarely reported in spinal gliomas, indicated a relatively favorable functional prognosis.

Endotracheal Tube Obstruction Experienced during an Anterior Cervical Discectomy and Fusion.

During anterior cervical discectomy and fusion (ACDF), endotracheal tube difficulties are anticipated at the operative level but are unexpected elsewhere in the airway. We report the case of a 66-year-old woman who underwent C4/C5 ACDF to treat adjacent segment disease following a previous anterior cervical fixation surgery. Shortly after her lower jaw was elevated and the fusion cage was inserted, a rise in airway pressure was observed, indicating impaired breathing. Subsequent examination revealed a bent endotracheal tube in the oral cavity as the cause of the respiratory impairment. During anterior cervical surgery, elevating the lower jaw can cause the tongue root to press against the endotracheal tube. Reinforced endotracheal tubes, with a spiral-wound wire in the inner wall, would effectively prevent this issue. In the unlikely event of impaired breathing during such an operation, the oral cavity should be inspected for confirmation of an open airway.

Clinical Safety Assessment of Autologous Freeze-Drying Platelet-Rich Plasma for Bone Regeneration in Maxillary Sinus Floor Augmentation: A Pilot Study.

The purpose of this clinical study is to evaluate the safety and preliminary efficacy of autologous freeze-drying platelet-rich plasma (FD-PRP) on bone regeneration in maxillary sinus floor augmentation as a preliminary pilot study. Five patients that required sinus floor augmentation to facilitate the placement of dental implants participated in this clinical study. The PRP was prepared from the autologous peripheral blood and was lyophilized and stored at -20 °C for 4 weeks before surgery. At surgery, triple-concentrated FD-PRP (x3FD-PRP) mixed with synthetic bone grafting materials was rehydrated following the transplantation into the sinus floor. The primary outcome was a safety verification of x3FD-PRP, evaluated in terms of the clinical course and consecutive blood tests. The secondary outcome was clinical efficacy focused on bone regeneration in sinus floor augmentation evaluated by radiographic examination and implant stability. There were no adverse events, such as systemic complications, excessive inflammatory reactions, severe infection, or local site healing complications, besides those on the usual course associated with surgery. Vertical augmented height was maintained, and the initial stability of implants was achieved post-operatively in 6 months. The results obtained in this study suggest that x3FD-PRP can be used safely for bone engineering in clinical practice. Further studies are required to draw a conclusion concerning the efficacy of x3FD-PRP since this was a pilot study with a single arm and a small sample size.

Postoperative Cervicothoracic Kyphosis Following Infantile Intramedullary Tumor Resection Accelerates Neurological Deterioration.

Intramedullary spinal cord tumors are rare in children. Regardless of the type of tumor, surgical removal is thought to improve progression-free survival. However, postoperative kyphosis is a serious problem in children, who can expect long-term survival. We present a pediatric case of neurofibromatosis type 2-related spinal ependymoma at the cervicothoracic regions where acute neurological deterioration was developed due to a combination of tumor recurrence and postoperative kyphotic deformity. In the first surgery, subtotal tumor resection was performed via osteoplastic laminotomy. Postoperative radiological evaluation at several months showed cervicothoracic junctional kyphosis, which subsequently made a significant improvement by lifestyle instructions. However, 22 months after the surgery, he exhibited rapid neurological deterioration caused by the regrowth of the recurrent tumor and re-emergence of kyphotic deformity, which led to the fixed laminar flap sank into the spinal canal. Therefore, a second surgery was performed 23 months after the first surgery, and gross total removal was achieved. Osteoplastic laminotomy is presumed to reduce the occurrence of postoperative kyphosis compared with laminectomy, but there have been no reports on the spinal cord compression by plunging of the re-fixed laminar flap into the spinal canal. The kyphosis deformity increases the chance of re-fixed laminar flap coming off, thereby accelerating neurological injury on top of the neural damage by tumor recurrence itself. Therefore, pediatric patients with spinal cord tumors should be carefully managed in terms of recurrent tumors and postoperative kyphosis, and timely surgical intervention is necessary before kyphotic deformity becomes evident.

Double Crush Syndrome of the Lower Limb in L5 Radiculopathy and Peroneal Neuropathy: A Case Report.

Double crush syndrome (DCS) is a clinical condition involving impingement of the spinal and peripheral nerves. DCS of the lower limbs has been recognized; however, no detailed reports have been published. Herein, we report a rare case of the coexistence of L5 radiculopathy and peroneal nerve entrapment neuropathy. The patient suffered from pain in the left lower leg and left foot combined with muscle weakness in the left leg without a Tinel-like sign in the peroneal tunnel area. MRI showed a deficit in the left L5 nerve root sleeve, and X-ray imaging revealed L5 spondylolysis. Lumbar fusion surgery was performed at L5-S1. Subsequently, the patient's symptoms were partially improved, but the pain and toe and ankle motor weakness persisted. In addition, a Tinel-like sign appeared at the entrapment point of the peroneal nerve. The entrapped peroneal nerve was decompressed, and the patient's symptoms improved. The patient had L5 radiculopathy owing to the improvement in his symptoms in the upper leg before and after lumbar surgery. It is unclear why no Tinel-like sign was detected before the first surgery, but we hypothesized that L5 nerve disorder may mask the symptoms triggered by compression of the peroneal nerve due to the complex pathology of DCS and dynamic factors. Distinguishing between radiculopathy and relative peripheral neuropathy should always be a consideration. DCS may mask characteristic symptoms, and it is important to carefully follow up the patient to detect changes in his or her condition.

Spontaneous Rupture of a Huge Presacral Tarlov Cyst Leading to Dramatic Neurologic Recovery.

BACKGROUND: This manuscript discusses the case of huge presacral Tarlov cysts (TCs) and the substantial neurologic recovery noted in the patient following spontaneous rupture of the most prominent cyst. Perineural or TCs are nerve root cysts, which are usually incidental findings on magnetic resonance imaging (MRI) and are most frequently observed in the sacral spine. Symptomatic lesions are rarely encountered. CASE DESCRIPTION: In this case, a 44-year-old woman presented with anal and vulva pain on the right side, and bladder and bowel dysfunction. MRI of the lumbosacral spine showed multiple huge bilateral TCs located within the presacral space from S1-3. There was a substantially large right-sided S3 cyst that was presumed to be responsible for her symptoms. Surgical intervention was considered; however, her symptoms improved significantly during the waiting period for surgery because of spontaneous rupture of the right-sided S3 cyst, as confirmed on follow-up MRI. On follow-up over a 1-year period, the patient had been very well with no recurrent symptoms. CONCLUSIONS: To our knowledge, this is the first report of spontaneous cyst rupture and resultant neurologic improvement in a case of symptomatic presacral TCs.

Preoperative Intracranial Dissemination of Spinal Myxopapillary Ependymoma Attributed to Tumor Hemorrhage.

BACKGROUND: Spinal myxopapillary ependymoma (SME), generally considered a benign entity, can exhibit brain and whole-spine metastases as well as local recurrence after surgery. However, the presence of preoperative retrograde intracranial dissemination at the time of diagnosis is very rare. CASE DESCRIPTION: We report a case of SME in a 22-year-old man who presented with acute exacerbation of chronic back pain shooting down both thighs and weakness in both legs. Magnetic resonance imaging of the brain and whole spine showed an enhancing mass occupying the majority of the spinal canal at the L1-L2 level and multiple foci dissemination, including in the right pons, lateral midbrain, and occipital lobe, and at the C7, Th6, L4, and S2 levels of the spinal canal at the time of diagnosis. On gross total removal of the dominant tumor located at the L1-L2 level, severe intradural arachnoiditis and syrinx filled with xanthochromic cerebrospinal fluid was noted, indicating the presence of previous tumor hemorrhage. Histopathologic analysis of the tumor supported SME diagnosis, and <1% of cells showed Ki-67 expression. We speculated that distant retrograde dissemination could have been attributed to metastatic spread through cerebrospinal fluid caused by tumor hemorrhage, which may explain distant dissemination despite low expression of Ki-67. CONCLUSIONS: Screening of the whole brain and spine at the time of diagnosis is imperative when tumor is detected at any level of the neuraxis. The present case of SME with a preoperative intracranial lesion is the fifth case documented in the medical literature.

Complete resection and untethering of the cervical and thoracic spinal dermal sinus tracts in adult patients.

Dermal sinus tracts (DSTs) of the cervical and thoracic spine are extremely rare, particularly in adult patients because diagnosis is typically made in the early stage after birth by pediatricians. These cases should be treated surgically as soon as possible to prevent neurological sequelae. This report describes two rare adult cases with cervical and thoracic spine DSTs. The first patient presented with back pain and headache, whose skin lesion had been long known, but disregarded since birth. The second patient had long suffered from residual cervical myelopathy from the prior incomplete surgical treatment. Both cases had these sinus tracts excised completely and had spinal cord untethered successfully without any neurological deterioration. There has been a trend toward earlier diagnosis of these entities, but still some cases that were diagnosed in a delayed fashion or underwent incomplete treatment are reported. Improper management during childhood could lead to irreversible neurological deficit caused by spinal cord tethering and/or direct compression due to DSTs-associated tumors. The early detection and prompt surgical intervention improve the chance of a good surgical outcome. Furthermore, complete excision of the sinus tracts and associated tumors could help prevent future bacterial contamination and recurrence.

Thoracic Disc Herniation Manifesting as Abdominal Pain Alone Associated with Thoracic Radiculopathy.

Symptomatic thoracic disc herniation (TDH) with thoracic radiculopathy alone is an extremely rare condition. Here, we report a rare case of TDH in a 52-year-old man who presented with medically refractory severe right flank pain. Based on pain distribution, pain intensity changes according to truncal position, ineffectiveness of intercostal nerve block, and radiological findings, his pain was determined to be caused by TDH at T9-10 level. Symptomatic TDH often requires invasive surgery. However, TDH with radiculopathy alone can be treated via a posterior approach without spinal cord manipulation or spinal fusion. We could eliminate the pain by removing TDH with hemilaminectomy and microdiscectomy using an O-arm-based navigation system.

Possible Double Crush Syndrome Caused by Iatrogenic Acquired Lumbosacral Epidermoid Tumor and Concomitant Sacral Tarlov Cyst.

We describe a rare case of 42-year-old female who had possible double crush syndrome caused by iatrogenic spinal epidermoid tumor (ET) associated with lumbar puncture as well as concomitant sacral Tarlov cyst in close proximity. She presented with progressive left-sided perianal pain. She had a history of a Caesarean section with lumbar spinal anesthesia. Magnetic resonance imaging (MRI) demonstrated a relatively small intradural extramedullary solid lesion at L5/S1 level and cystic lesion at S2 level. We considered there were two different lesions, such as a tumor and Tarlov cyst; however, we could not rule out the possibility of a single lesion with two different components. Furthermore, there was a distinct compression at more than one locations along the course of the left S2 nerve root and we suspected possible double crush syndrome. We conducted tumor removal and the lesion turned out to be two different pathologies, such as an ET and Tarlov cyst. Both lesions were intraopertively pinching the left S2 nerve root at different sites as expected. The tumor was successfully removed and the cyst wall was imbricated and sutured. We need to take the possibility of ET into consideration if the patient underwent invasive spinal procedure previously. We also have to pay attention to the possibility of double crush syndrome if the nerve root possibly holding the responsibility for symptoms is compressed at two or more sites. This is the first report of possible double crush syndrome caused by acquired spinal tumor and congenital Tarlov cyst.