Spinal Epidural Lipoma on the Ventral Dura Side and Intervertebral Foramen Causing Lumbar Radiculopathy.

A 56-year-old obese man with a body mass index of 30.9 kg/m2 presented with left sciatica and intermittent claudication. Computed tomography scans showed a posterior vertebral scalloping change in L3, L4, and L5. Meanwhile, magnetic resonance imaging revealed epidural mass posterior to the L3, L4, and L5 vertebral bodies. The solitary mass was isosignal to subcutaneous fat and asymmetrically compressed to the left side of the dural sac and L4 nerve root, as observed on axial T1- and T2-weighted images. To the best of our knowledge, there have been few reports of a solitary epidural lipoma causing lumbar radiculopathy. The patient underwent transforaminal lumbar interbody fusion at L4-L5, and his symptoms then resolved. Thus, we recommend decompression and fixation as appropriate management for lumbar radiculopathy caused by epidural lipoma located on the ventral side of the dura and intervertebral foramen.

Efficacy of platelet-rich plasma impregnation for unidirectional porous ß-tricalcium phosphate in lateral lumbar interbody fusion: study protocol for a prospective controlled trial.

BACKGROUND: The use of platelet-rich plasma has been increasing in spinal fusion surgery. However, the efficacy of platelet-rich plasma in lateral lumbar interbody fusion is unclear. In Japan, Affinos,® (Kuraray Co., Tokyo, Japan), a ß-tricalcium phosphate artificial bone, has been increasingly used for spinal fusion. The purpose of this trial is to demonstrate whether Affinos® impregnated with platelet-rich plasma can achieve a higher fusion rate and better clinical outcomes than Affinos® alone. METHODS: The current study is a prospective randomized controlled trial. This trial will include consecutive patients scheduled for lateral lumbar interbody fusion. An intervertebral cage for lateral lumbar interbody fusion has two spaces for bone grafts. As a consequence, two bone grafts are inserted at each intervertebral level. In this study, an artificial bone with platelet-rich plasma will be inserted into one space, and an artificial bone without platelet-rich plasma will be inserted into the other space. We will compare the fusion rates between the bone grafts with and without platelet-rich plasma. Our primary endpoint will be the interbody fusion rate at 1 year after surgery. DISCUSSION: This trial will verify the efficacy of platelet-rich plasma with Affinos® for bony fusion in lateral lumbar interbody fusion. It will also provide substantial evidence for the effectiveness and safety of platelet-rich plasma in spinal fusion surgery. TRIAL REGISTRATION: Japan Registry of Clinical Trials (jRCT) jRCTb032200199 . First registered on 13 November 2020. jRCT is approved as a member of the Primary Registry Network of WHO ICTRP.

Surgical Apgar Score and Controlling Nutritional Status Score are significant predictors of major complications after cervical spine surgery.

Nutritional screening scores, including Controlling Nutritional Status (CONUT) Score and Surgical Apgar Score (SAS), which reflect intraoperative hemodynamics, have been reported to be useful for predicting major postoperative complications in various kinds of surgery. We assessed independent risk factors for major complications after cervical spine surgery using those scoring measurements. We retrospectively reviewed medical records of patients who underwent cervical spine surgery at our institution from 2014 to 2019. Baseline clinical information, including the CONUT Score, and surgical factors, including the SAS, were assessed as risk factors for major postoperative complications. We analyzed 261 patients. Major postoperative complications occurred in 40 cases (15.3%). In the multivariate analysis, SAS (odds ratio [OR], 0.42; P < 0.01), CONUT (OR, 1.39; P < 0.01), and operative time (OR, 1.42; P < 0.01) were significant independent risk factors of major complications. The area under the SAS curve was 0.852 in the receiver operating characteristic curve analysis. Postoperative hospitalization duration was significantly longer in major complications group. Evaluating preoperative nutritional condition and intraoperative hemodynamics with CONUT score and SAS was useful for predicting major postoperative complications of cervical spine surgery. In addition, both scoring measurements are easily calculated, objective evaluations. Perioperative management utilizing those scoring measurements may help prevent them.

A Case of Postoperative Recurrent Lumbar Disc Herniation Conservatively Treated with Novel Intradiscal Condoliase Injection.

Although postoperative recurrent lumbar disc herniation (rec-LDH) is uncommon, it is a challenging situation that requires revision surgery when conservative treatment fails. Recently, an agent inducing chemical dissolution of the nucleus pulposus using condoliase has been approved as a novel intradiscal treatment for LDH. To date, no evidence has been reported regarding its effectiveness in the treatment of postoperative rec-LDH. A 25-year-old man with a history of LDH in L4/5, who underwent transforaminal full endoscopic lumbar discectomy when he was 17 years old, complained of severe pain radiating to his left leg since 1 month. The straight leg-raising test was limited to 25° on the left side. Lumbar T2-weighted magnetic resonance imaging (MRI) showed intracanal, left-sided transligamentous disc herniation at L4/5 with high-signal intensity. Because the conservative treatment with oral analgesics and selective left L5 nerve root block failed, the patient requested intradiscal condoliase injection instead of revision surgery. There were no adverse events reported after the condoliase treatment, and the pain radiating to the left leg improved within 2 weeks. A lumbar MRI performed 2 months after treatment revealed that the disc herniation had significantly decreased in size. The straight leg-raising test examined 3 months after treatment was negative. In this case, the disc herniation was of the transligamentous type and showed a high-signal intensity on T2-weighted MRI which could be suitably treated by condoliase injection therapy. This case report is the first to suggest that intradiscal condoliase injection could be a useful and novel conservative treatment option to treat postoperative rec-LDH.

Paravertebral foramen screw fixation for posterior cervical spine surgery: clinical case series.

OBJECTIVE: The goal of this study was to clarify the clinical utility of paravertebral foramen screws (PVFSs) and to determine intraoperative indicators for appropriate screw placement during posterior cervical fusion surgery to improve its safety. METHODS: The authors included data from 46 patients (29 men and 17 women, mean age 61.7 years) who underwent posterior cervical spine surgery with 94 PVFSs. Of the 94 PVFSs, 77 were used in C6, 9 in C3, 5 in C4, and 3 in C5. According to the cervical lateral radiographic view, the authors divided the 94 PVFSs into 3 groups as follows: a longer group, in which the tip of PVFS was located anteriorly from the line of the posterior wall of the vertebral body (> +0 mm); an intermediate group, in which the screw tip was located up to 2 mm posteriorly to the posterior wall of the vertebral body (-2 to 0 mm); and a shorter group, in which the screw tip was located more than 2 mm posteriorly (< -2 mm). The accuracy of screw placement was assessed using CT imaging in the axial plane, and the proportion of screws penetrating a vertebral foramen or a transverse foramen was compared between the 3 groups. Screw loosening was defined as a lucent zone around the screw evaluated on cervical radiography at 1 year after surgery. Complications related to PVFS insertion and revision surgery related to PVFS were evaluated. RESULTS: The authors classified 25 PVFSs into the longer group, 43 into the intermediate group, and 26 into the shorter group. The proportion of screws penetrating a vertebral foramen was largest in the shorter group, and the proportion penetrating a transverse foramen was largest in the longer group. Screw loosening was confirmed for 3 of 94 PVFSs. One PVFS inserted in C6 unilaterally within a long construct from C2 to C7 showed loosening, but it did not cause clinical symptoms. Revision surgery was required for 2 PVFSs inserted in C3 bilaterally as the lower instrumented vertebra in occiput-cervical fusion because they pulled out. There was no neurovascular complication related to PVFS insertion. CONCLUSIONS: PVFSs are useful for posterior cervical fusion surgery as alternative anchor screws, and the line of the posterior wall of the cervical body on lateral fluoroscopic images is a potential intraoperative reference to indicate an appropriate trajectory for PVFSs.

Continuous local antibiotic perfusion for patients with surgical site infection after instrumented spinal surgery; a novel technique to retain the implants.

OBJECTIVES: To describe the novel technique of continuous local antibiotic perfusion (CLAP) for a surgical site infection (SSI) after instrumented spinal surgery. METHODS: CLAP was applied to 4 continuous patients at our institution who developed SSI after instrumented spinal surgery. RESULTS: All 4 patients were successfully treated and the infection was controlled. The implant was retained in all patients. The duration of CLAP ranged from 2 to 3 weeks. The blood level of the antibiotic used (gentamicin) at 1 week after the initiation of CLAP did not increase in any patient. No other adverse events occurred in any patient. Dramatic improvements in laboratory parameters, including the white blood cell (WBC) counts and C-reactive protein (CRP) levels were seen in every patient at 1 week after the initiation of CLAP. CONCLUSIONS: CLAP controlled the infection without severe adverse events in all 4 patients, and the implants were retained. Despite its cost and the discomfort of patients, CLAP may become an option for the treatment of SSIs after instrumented spinal surgery. A large number of case series are needed to verify the efficacy of CLAP for patients with SSIs after instrumented spinal surgery.

The fatty degeneration of the lumbar erector spinae muscles affects dynamic spinal compensation ability during gait in adult spinal deformity.

This study aimed to investigate whether fat infiltration in lumbar paravertebral muscles assessed by magnetic resonance imaging (MRI) could be related to dynamic sagittal spino-pelvic balance during gait in adult spinal deformity (ASD). This is a retrospective analysis of 28 patients with ASD. The fat infiltration rate of lumbar erector spinae muscles, multifidus muscles and psoas major muscles was measured by T2 weighted axial MRI at L1-2 and L4-5. Dynamic sagittal spinal and pelvic angles during gait were evaluated using 3D motion analysis. The correlation between fat infiltration rate of those muscles with variations in dynamic kinematic variables while walking and static radiological parameters was analyzed. Spinal kyphosis and pelvic anteversion significantly increased during gait. Fat infiltration rate of erector spinae muscles at L1-2 was positively correlated with thoracic kyphosis (r = 0.392, p = 0.039) and pelvic tilt (r = 0.415, p = 0.028). Increase of spinal kyphosis during walking was positively correlated with fat infiltration rate of erector spinae muscles both at L1-2 (r = 0.394, p = 0.038) and L4-5 (r = 0.428, p = 0.023). Qualitative evaluation of lumbar erector spinae muscles assessed by fat infiltration rate has the potential to reflect dynamic spino-pelvic balance during gait.

What Trajectory Is Safe for Double Penetrating Endplate Screw Posterior Spinal Fusion Surgery in the Thoracolumbar Region?

BACKGROUND: The penetrating end plate screw (PES) technique improved the fixation strength of the pedicle screw by penetrating the end plate in posterior fusion. The "double" PES, which is a trajectory that penetrates both the upper end plate of the corresponding vertebra and the lower end plate of the upper adjacent vertebral body, provides a stronger tricortical fixation but requires a stricter trajectory. The purpose of this study was to measure the cephalad angles from T7-L5 that would allow a safe trajectory for "double" PES. METHODS: We analyzed 1078 pedicles of 539 vertebral bodies of 50 consecutive cases (27 males and 23 females, mean age, 63.3 years) who underwent computed tomography (CT) myelography for evaluation of spinal disorders. The mean cephalad angle to obtain the double PES trajectory of each vertebra was examined, except for cases in which the appropriate trajectory would perforate the pedicles. RESULTS: The cephalad angle for the appropriate trajectory of "double" PES ranged from 23.4 to 37.6 degrees in the thoracic spine and 34.8 to 40.8 degrees in the lumbar spine. The ratio of pedicle perforation was significantly higher at T7 (16%), L4 (26%), and L5 (52%). CONCLUSIONS: It is important to measure the optimal cephalad angle by preoperative computed tomography imaging according to the vertebral level. In L4 and L5, "double" PES should be avoided because it is often unsafe.

Correlation between osteoarthritis of the atlantoaxial facet joint and a high-riding vertebral artery.

BACKGROUND: A high-riding vertebral artery (HRVA) is an intraosseous anomaly that narrows the trajectory for C2 pedicle screws. The prevalence of a HRVA is high in patients who need surgery at the craniovertebral junction, but reports about HRVAs in subaxial cervical spine disorders are limited. We sought to determine the prevalence of HRVAs among patients with subaxial cervical spine disorders to elucidate the potential risk for VA injury in subaxial cervical spine surgery. METHODS: We included 215 patients, 94 were with a main lesion from C3 to C7 (subaxial group) and 121 were with a main lesion from T1 to L5 (thoracolumbar group). A HRVA was defined as a maximum C2 pedicle diameter of < 3.5 mm on axial CT. The sex, age of patients, body mass index (BMI), osteoarthritis of the atlantoaxial (C1-2) facet joints, and prevalence of a HRVA in the 2 groups were compared and logistic regression was used to identify the factors correlated with a HRVA. RESULTS: The patients in the subaxial group were younger than those in the thoracolumbar group, but their sex and BMI did not differ significantly between the 2 groups. The mean osteoarthritis grade of the C1-2 facet joints of patients in the subaxial group was significantly higher than that in those in the thoracolumbar group. A HRVA was found in 26 patients of 94 (27.7 %) in the subaxial group and in 19 of 121 (15.7 %) in the thoracolumbar group. The prevalence of a HRVA in the subaxial group was significantly higher and osteoarthritis of C1-2 facet joints correlated significantly with a HRVA. CONCLUSIONS: The prevalence of a HRVA in patients with subaxial cervical spine disorders is higher than in those without and osteoarthritis of the C1-2 facet joints is correlated with a HRVA.

Characteristics of relief and residual low back pain after discectomy in patients with lumbar disc herniation: analysis using a detailed visual analog scale.

BACKGROUND: Several authors have reported favorable results in low back pain (LBP) for patients with lumbar disc herniation (LDH) treated with discectomy. However, detailed changes over time in the characteristics and location of LBP before and after discectomy for LDH remain unclear. To clarify these points, we conducted an observational study to determine the detailed characteristics and location of LBP before and after discectomy for LDH, using a detailed visual analog scale (VAS) bilaterally. METHODS: We included 65 patients with LDH treated by discectomy in this study. A detailed VAS for LBP was administered with the patient under 3 different conditions: in motion, standing, and sitting. Bilateral VAS was also administered (affected versus opposite side) for LBP, lower extremity pain (LEP), and lower extremity numbness (LEN). The Oswestry Disability Index (ODI) was used to quantify clinical status. Changes over time in these VAS and ODI were investigated. Pfirrmann grading and Modic change as seen by magnetic resonance imaging (MRI) were reviewed before and 1 year after discectomy to determine disc and endplate condition. RESULTS: Before surgery, LBP on the affected side while the patients were in motion was significantly higher than LBP while they were sitting (p = 0.025). This increased LBP on the affected side in motion was improved significantly after discectomy (p < 0.001). By contrast, the residual LBP while sitting at 1 year after surgery was significantly higher than the LBP while they were in motion or standing (p = 0.015). At 1 year following discectomy, residual LBP while sitting was significantly greater in cases showing changes in Pfirrmann grade (p = 0.002) or Modic type (p = 0.025). CONCLUSIONS: Improvement of LBP on the affected side while the patient is in motion suggests that radicular LBP is improved following discectomy by nerve root decompression. Furthermore, residual LBP may reflect increased load and pressure on the disc and endplate in the sitting position.

A Case of Cardiac Arrest during C1 Laminectomy for Irreducible Atlantoaxial Subluxation.

We report a case of cardiac arrest, which occurred during C1 laminectomy for irreducible atlantoaxial subluxation, with return of spontaneous circulation (ROSC) upon interruption of the laminectomy. A 60-year-old woman with rheumatoid arthritis presented with neck pain, bilateral finger numbness, and bladder-rectal disturbance. Simple radiograph images showed that the atlantodental interval (ADI) was enlarged to 8 mm, and magnetic resonance imaging revealed severe spinal stenosis at C1. She was diagnosed with cervical spondylotic myelopathy due to atlantoaxial subluxation. Cardiac arrest occurred twice during the C1 laminectomy and occipito-cervical fusion (Occ-C3), and ROSC occurred without any treatment. There was no postoperative worsening of neurological symptoms, and the improvement of sensory and motor palsy was favorable. The pathogenic mechanism was presumed to be trigeminocardiac reflex. Cardiac arrest during upper cervical spine surgery is an important intraoperative complication of which operators should be made aware.

Comparison of clinical results of decompression/fusion surgery for paralysis caused by metastatic spinal tumors of unknown versus known origin.

Objective: Whether or not emergent decompression/fusion surgery for paralysis caused by metastatic spinal tumors of unknown origin improves patient neurological outcome and survival remains unclear. This study aimed to evaluate the clinical outcomes of emergent decompression/fusion surgery for paralysis caused by spinal tumors of unknown or not previously diagnosed origin. Patients and Methods: Data from the medical records of 11 patients with spinal tumors of unknown origin (study group) were compared with those of 15 patients with metastatic spinal tumors of known origin (control group). The outcome measures were postoperative performance status, motor function evaluated with the Frankel grade, and actual survival after surgery as compared with the estimated survival calculated using the Tokuhashi score. χ2 analyses were performed to evaluate differences between the groups. Results: The mean performance status was 3.6 preoperatively, which improved to 2.9 postoperatively (P<0.05), in the unknown origin group and 3.6 preoperatively, which improved to 2.7 postoperatively (P<0.05), in the control group. Seven patients (64%) in the unknown origin group showed improvement in paralysis by ≥1 Frankel grade. By contrast, only 4 patients (27%) in the control group showed improvement in paralysis. The unknown origin group tended to show better improvement (P=0.05). All the patients in the unknown origin group underwent adjuvant therapy after definitive diagnosis following surgery. The unknown origin group showed a slight tendency toward better survival than toward the estimated survival. Conclusion: Emergent decompression/fusion surgery for patients with paralysis caused by metastatic tumors of unknown origin is potentially useful for diagnosing tumor origin and improving neurological outcomes and performance status, and thus for extending survival.

Percutaneous endoscopic discectomy might be effective in selected cases of pyogenic spondylitis.

BACKGROUND: Percutaneous endoscopic discectomy (PED) has been reported to be an effective procedure and minimally invasive surgical therapy for various spinal pathologies. OBJECTIVE: To evaluate the clinical outcome of patients with pyogenic spondylitis who were treated with PED. METHODS: Twenty-four patients with pyogenic spondylitis who underwent PED were evaluated for medical history, level of the affected intervertebral space, mode of onset, plain radiographs, epidural or psoas abscesses on MRI, results of blood and intraoperative sample cultures, preoperative C-reactive protein (CRP) level, time until postoperative CRP normalization (CRP < 0.3), and any additional surgery. Patients who underwent additional surgery and showed uncontrollable inflammation were considered to have "failed" PED for pyogenic spondylitis. To elucidate the factors that were significantly associated with a failure of PED for pyogenic spondylitis, statistical analyses were conducted by univariate analysis. RESULTS: Control of inflammation was achieved in 19 of 24 patients (76%) after PED for pyogenic spondylitis. The remaining five patients failed to achieve infection control by PED. One such patient was not able to control the infection after PED, and another patient developed an epidural abscess 2 weeks after PED. Remaining three "failed" patients had exacerbations of their infections during the postoperative course and required additional surgery. Univariate analyses demonstrated that diabetes mellitus (DM; p = 0.05), hemodialysis due to DM-induced renal failure (p = 0.02), concomitant malignant disease (p = 0.09), and acute onset (p = 0.05) were possibly correlated with PED failure. Stepwise logistic regression analysis revealed that hemodialysis due to DM-induced renal failure was an independent factor associated with PED failure (p = 0.03). CONCLUSIONS: PED might be considered as one of the alternative therapeutic options before invasive radical surgeries for pyogenic spondylitis after failure of standard conservative therapy. Even by less invasive PED, pyogenic spondylitis patients with DM-hemodialysis showed poor outcome.

Positive-pressure ventilation attenuates subarachnoid-pleural fistula after thoracic spinal surgery: A report of two cases.

BACKGROUND: Dural tear and cerebrospinal fluid (CSF) leakage is known to be a complication of anterior thoracic spine surgery. If dural tear occurs on the ventral side of dura in combination with a pleural injury, it potentially becomes a subarachnoid-pleural fistula. The pressure gradient permits continuous flow of CSF from the subarachnoid space into the cavum thorax, resulting in an intractable subarachnoid-pleural fistula. We report two cases of successfully treated subarachnoid-pleural fistula using noninvasive positive-pressure ventilation (NPPV). METHODS: Two patients, a 52-year-old man and a 54-year-old woman, underwent anterior thoracic spine surgery to treat thoracic myelopathy caused by spinal tumor and ossification of the posterior longitudinal ligament. During surgery, dural tear and CSF leakage to the cavum thorax due to perforation of the dura was observed. We treated with polyglycolic acid sheet (Neovel®) in combination with fibrin glue; a suction drainage tube was placed at the subfascial level and the wound was drained with negative pressure. However, after removal of the drainage tube, subarachnoid-pleural fistula was proven. We applied NPPV to the patients. RESULTS: We used the application of NPPV for 2 weeks in the first patient and 1 week in the second patient. In both of them, subarachnoid-pleural fistula was attenuated without apparent adverse events. CONCLUSION: NPPV is noninvasive and potentially useful therapy to attenuate subarachnoid-pleural fistula after thoracic spinal surgery.

Methotrexate-related lymphoproliferative disorder of the lumbar spine origin presenting with severe low-back pain: case report.

The use of methotrexate (MTX) to treat rheumatoid arthritis (RA) is increasing. Recently, MTX-associated lymphoproliferative disorder (MTX-LPD) has been frequently reported as lymphoma occurring during MTX therapy. The authors report their experience with a relatively rare case of MTX-LPD presenting in the lumbar spine. The patient, a 73-year-old woman who experienced low-back pain while receiving MTX therapy for RA, was suspected of having developed MTX-LPD based on her medical history, images of the L1 vertebra, and transpedicular biopsy results. One week after discontinuing MTX, the patient's low-back pain reportedly improved. The woman was diagnosed with MTX-LPD based on histopathological findings. MTX discontinuation alone coincided with spontaneous tumor regression. Because MTX-LPD can occur in tissues other than lymph nodes, such as in bones and joints, it is a disease that should be considered when diagnosing spinal tumors in patients receiving MTX therapy.

High-resolution axial MR imaging of tibial stress injuries.

PURPOSE: To evaluate the relative involvement of tibial stress injuries using high-resolution axial MR imaging and the correlation with MR and radiographic images. METHODS: A total of 33 patients with exercise-induced tibial pain were evaluated. All patients underwent radiograph and high-resolution axial MR imaging. Radiographs were taken at initial presentation and 4 weeks later. High-resolution MR axial images were obtained using a microscopy surface coil with 60 × 60 mm field of view on a 1.5T MR unit. All images were evaluated for abnormal signals of the periosteum, cortex and bone marrow. RESULTS: Nineteen patients showed no periosteal reaction at initial and follow-up radiographs. MR imaging showed abnormal signals in the periosteal tissue and partially abnormal signals in the bone marrow. In 7 patients, periosteal reaction was not seen at initial radiograph, but was detected at follow-up radiograph. MR imaging showed abnormal signals in the periosteal tissue and entire bone marrow. Abnormal signals in the cortex were found in 6 patients. The remaining 7 showed periosteal reactions at initial radiograph. MR imaging showed abnormal signals in the periosteal tissue in 6 patients. Abnormal signals were seen in the partial and entire bone marrow in 4 and 3 patients, respectively. CONCLUSIONS: Bone marrow abnormalities in high-resolution axial MR imaging were related to periosteal reactions at follow-up radiograph. Bone marrow abnormalities might predict later periosteal reactions, suggesting shin splints or stress fractures. High-resolution axial MR imaging is useful in early discrimination of tibial stress injuries.