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Objective To assess the efficacy of caudal epidural steroid or saline injection in chronic lumbar radiculopathy in the short (6 weeks), intermediate (12 weeks), and long term (52 weeks).

Design Multicentre, blinded, randomised controlled trial.

Setting Outpatient multidisciplinary back clinics of five Norwegian hospitals.

Participants Between October 2005 and February 2009, 461 patients assessed for inclusion (presenting with lumbar radiculopathy >12 weeks). 328 patients excluded for cauda equina syndrome, severe paresis, severe pain, previous spinal injection or surgery, deformity, pregnancy, ongoing breast feeding, warfarin therapy, ongoing treatment with non-steroidal anti-inflammatory drugs, body mass index >30, poorly controlled psychiatric conditions with possible secondary gain, and severe comorbidity.

Interventions Subcutaneous sham injections of 2 mL 0.9% saline, caudal epidural injections of 30 mL 0.9% saline, and caudal epidural injections of 40 mg triamcinolone acetonide in 29 mL 0.9% saline. Participants received two injections with a two week interval.

Main outcome measures Primary: Oswestry disability index scores. Secondary: European quality of life measure, visual analogue scale scores for low back pain and for leg pain.

Results Power calculations required the inclusion of 41 patients per group. We did not allocate 17 of 133 eligible patients because their symptoms improved before randomisation. All groups improved after the interventions, but we found no statistical or clinical differences between the groups over time. For the sham group (n=40), estimated change in the Oswestry disability index from the adjusted baseline value was −4.7 (95% confidence intervals −0.6 to −8.8) at 6 weeks, −11.4 (−6.3 to −14.5) at 12 weeks, and −14.3 (−10.0 to −18.7) at 52 weeks. For the epidural saline intervention group (n=39) compared with the sham group, differences in primary outcome were −0.5 (−6.3 to 5.4) at 6 weeks, 1.4 (−4.5 to 7.2) at 12 weeks, and −1.9 (−8.0 to 4.3) at 52 weeks; for the epidural steroid group (n=37), corresponding differences were −2.9 (−8.7 to 3.0), 4.0 (−1.9 to 9.9), and 1.9 (−4.2 to 8.0). Analysis adjusted for duration of leg pain, back pain, and sick leave did not change this trend.

Conclusions Caudal epidural steroid or saline injections are not recommended for chronic lumbar radiculopathy.

Trial registration Current Controlled Trials ISRCTN No 12574253.

Spinal epidural hematoma is a well known complication of spinal surgery. Clinically insignificant small epidural hematomas develop in most spinal surgeries following laminectomy. However, the incidence of clinically significant postoperative spinal epidural hematomas that result in neurological deficits is extremely rare. In this report, we present a 33-year-old female patient whose spinal surgery resulted in postoperative spinal epidural hematoma. She was diagnosed with lumbar disc disease and underwent hemipartial lumbar laminectomy and discectomy. After twelve hours postoperation, her neurologic status deteriorated and cauda equina syndrome with acute spinal epidural hematoma was identified. She was immediately treated with surgical decompression and evacuation of the hematoma. The incidence of epidural hematoma after spinal surgery is rare, but very serious complication. Spinal epidural hematomas can cause significant spinal cord and cauda equina compression, requiring surgical intervention. Once diagnosed, the patient should immediately undergo emergency surgical exploration and evacuation of the hematoma.

Lumbar epidural anesthesia is useful in a variety of chronic benign pain syndromes, including lumbar radiculopathy, low back pain syndrome, spinal stenosis, and vertebral compression fractures. Given the increased number of epidural nerve blocks being performed, some have reported unexplained complications of a transient or permanent nature and with varying degrees of severity. However, no case has been reported of a broken epidural needle tip retained in the lumbar facet joint area. This represents the first reported case presentation of foraminal stenosis developing in a patient after a retained epidural needle tip.

Background:

Facet cysts are implicated in neural compression in the lumbar spine. Surgery is the definitive treatment for symptomatic facet cysts since the failure rate for conservative treatment is quite high; however, the role of physical/manual medicine practitioners in the management of symptomatic facet cysts has not been well explored. This case report will add to the body of evidence of spontaneous resolution of symptoms associated with facet cysts in the chiropractic literature.

Case:

A 58 year old female presented with acute low back and right leg pain which she attributed to a series of exercise classes that involved frequent foot stomping. Physical examination did not elicit any objective evidence of radiculopathy but MRI and CT scans revealed a facet cyst impinging on the right L5 nerve root. Injections and surgery were recommended; however, the patient’s radicular symptoms completely resolved after three months without surgical intervention.

Summary:

There is currently a paucity of data in the literature regarding the chiropractor’s role in the management of symptomatic facet cysts. The case presented here has added to this literature and possible areas for future research have been explored.

Background

Chronic low back pain can be a manifestation of lumbar degenerative disease, herniation of intervertebral discs, arthritis, or lumbar stenosis. When nerve roots are compromised, low back pain, with or without lower extremity involvement, may occur. Local inflammatory processes play an important role in patients with acute lumbosciatic pain. The purpose of this study was to assess the value of erythrocyte sedimentation rate (ESR) and high sensitivity C-reactive protein (hsCRP) measurements in patients with chronic low back pain or radiculopathy.

Methods

ESR and hsCRP were measured in 273 blood samples from male and female subjects with low back pain and/or radiculopathy due to herniated lumbar disc, spinal stenosis, facet syndrome, and other diseases. The hsCRP and ESR were measured prior to lumbar epidural steroid injection.

Results

The mean ESR was 18.8 mm/h and mean hsCRP was 1.1 mg/L. ESR had a correlation with age.

Conclusions

A significant systemic inflammatory reaction did not appear to arise in patients with chronic low back pain.

Epidural abscess of the spinal column is a rare condition that can be fatal if left untreated. It promptly progresses and can cause neurologic paralysis, urinary retention or cauda equina syndrome. Compromised immune system that occurs in patients with diabetes mellitus, AIDS, chronic renal failure, alcoholism, or cancer is a predisposing factor. It mostly occurs in adults. Here we would like to report a case of spontaneous pyogenic lumbar epidural abscess with neurological deficit diagnosed in a 15 year old boy. We treated this case successfully with surgical microscopic decompression and drainage.

Objective

The purpose of this case report is to describe a case of metastatic non-Hodgkin lymphoma in the lumbar spine presenting as lumbar radiculopathy.

Clinical Features

A 46-year-old man sought care from his doctor of chiropractic for low back pain and right leg radiculopathy. The patient was referred for a magnetic resonance imaging (MRI) scan to evaluate for a suspected disk herniation. The MRI scan revealed 2 lumbar pathologic compression fractures with cauda equina compression, and MRI short tau inversion recovery (STIR) sagittal image of the lumbar spine showed high signal in T12 and S2.

Intervention and Outcome

The patient was referred for an immediate consultation with his medical physician with the preliminary diagnosis of metastatic bone lesions or primary bone lesions of unknown etiology. The patient underwent bone biopsy, computed tomography, and positron emission tomography scanning and was diagnosed with small cell non-Hodgkin lymphoma with osseous metastasis. The patient underwent chemo- and radiation therapy, and the lymphoma is now in remission 18 months later.

Conclusion

This case describes the presentation of metastatic non-Hodgkin lymphoma as a possible contributing cause in a patient presenting with lumbar radiculopathy, a common musculoskeletal condition. As well, this case highlights the importance of STIR sequences as part of a routine lumbar spine MRI examination. Without the STIR sequences, the additional deposits in T12 and S1 would not have been readily appreciated. Although metastatic non-Hodgkin lymphoma of the spine is rare, it should be remembered in the differential diagnoses.

Background and Objectives

Previous studies have concluded that transforaminal epidural steroid injections (ESIs) are more effective than interlaminar injections in the treatment of radiculopathies due to lumbar intervertebral disk herniation. There are no published studies examining the depth of epidural space using a transforaminal approach. We investigated the relationship between body mass index (BMI) and the depth of the epidural space during lumbar transforaminal ESIs.

Methods

Eighty-six consecutive patients undergoing lumbar transforaminal ESI at the L3-L4, L4-L5, and L5-S1 levels were studied. Using standard protocol, the foraminal epidural space was attained using fluoroscopic guidance. The measured distance from needle tip to skin was recorded (depth to foraminal epidural space). The differences in the needle depth and BMI were analyzed using regression analysis.

Results

Needle depth was positively associated with BMI (regression coefficient [RC], 1.13; P < 0.001). The median depths (in centimeters) to the epidural space were 6.3, 7.5, 8.4, 10.0, 10.4, and 12.2 for underweight, normal, preobese, obese I, obese II, and obese III classifications, respectively. Sex (RC, 1.3; P = 0.02) and race (RC, 0.8; P = 0.04) were also significantly associated with needle depth; however, neither factor remained significant when BMI was accounted as a covariate in the regression model. Age, intervertebral level treated, and oblique angle had no predictive value on foraminal depth (P > 0.2).

Conclusion

There is a positive association between BMI and transforaminal epidural depth, but not with age, sex, race, oblique angle, or intervertebral level.

Calcium pyrophosphate dihydrate (CPPD) deposition disease, also known as pseudogout, is a disease that causes inflammatory arthropathy in peripheral joints, however, symptomatic involvement of the intervertebral disc is uncommon. Herein, we describe a 59-yr-old patient who presented with cauda equina syndrome. Magnetic resonance imaging of the patient showed an epidural mass-like lesion at the disc space of L4-L5, which was compressing the thecal sac. Biopsy of the intervertebral disc and epidural mass-like lesion was determined to be CPPD deposits. We reviewed previously reported cases of pseudogout involving the lumbar intervertebral disc and discuss the pathogenesis and treatment of the disease.

Lumbar spinal stenosis, the results of congenital and degenerative constriction of the neural canal and foramina leading to lumbosacral nerve root or cauda equina compression, is a common cause of disability in middle-aged and elderly patients. Advanced neuroradiologic imaging techniques have improved our ability to localize the site of nerve root entrapment in patients presenting with neurogenic claudication or painful radiculopathy. Although conservative medical management may be successful initially, surgical decompression by wide laminectomy or an intralaminar approach should be done in patients with serious or progressive pain or neurologic dysfunction. Because the early diagnosis and treatment of lumbar spinal stenosis may prevent intractable pain and the permanent neurologic sequelae of chronic nerve root entrapment, all physicians should be aware of the different neurologic presentations and the treatment options for patients with spinal stenosis.

Images

We retrospectively evaluated 488 percutaneous pedicle screws in 110 consecutive patients that had undergone minimally invasive transforaminal lumbar interbody fusion (MITLIF) to determine the incidence of pedicle screw misplacement and its relevant risk factors. Screw placements were classified based on postoperative computed tomographic findings as “correct”, “cortical encroachment” or as “frank penetration”. Age, gender, body mass index, bone mineral density, diagnosis, operation time, estimated blood loss (EBL), level of fusion, surgeon’s position, spinal alignment, quality/quantity of multifidus muscle, and depth to screw entry point were considered to be demographic and anatomical variables capable of affecting pedicle screw placement. Pedicle dimensions, facet joint arthritis, screw location (ipsilateral or contralateral), screw length, screw diameter, and screw trajectory angle were regarded as screw-related variables. Logistic regression analysis was conducted to examine relations between these variables and the correctness of screw placement. The incidence of cortical encroachment was 12.5% (61 screws), and frank penetration was found for 54 (11.1%) screws. Two patients (0.4%) with medial penetration underwent revision for unbearable radicular pain and foot drop, respectively. The odds ratios of significant risk factors for pedicle screw misplacement were 3.373 (95% CI 1.095–10.391) for obesity, 1.141 (95% CI 1.024–1.271) for pedicle convergent angle, 1.013 (95% CI 1.006–1.065) for EBL >400 cc, and 1.003 (95% CI 1.000–1.006) for cross-sectional area of multifidus muscle. Although percutaneous insertion of pedicle screws was performed safely during MITLIF, several risk factors should be considered to improve placement accuracy.

Background/Objective:

Intervertebral disk herniation is relatively common. Migration usually occurs in the ventral epidural space; rarely, disks migrate to the dorsal epidural space due to the natural anatomical barriers of the thecal sac.

Design:

Case report.

Findings:

A 49-year-old man presented with 1 week of severe back pain with bilateral radiculopathy to the lateral aspect of his lower extremities and weakness of the ankle dorsiflexors and toe extensors. Lumbar spine magnetic resonance imaging with gadolinium revealed a peripheral enhancing dorsal epidural lesion with severe compression of the thecal sac. Initial differential diagnosis included spontaneous hematoma, synovial cyst, and epidural abscess. Posterior lumbar decompression was performed; intraoperatively, the lesion was identified as a large herniated disk fragment.

Conclusions:

Dorsal migration of a herniated intervertebral disk is rare and may be difficult to definitively diagnose preoperatively. Dorsal disk migration may present in a variety of clinical scenarios and, as in this case, may mimic other epidural lesions on magnetic resonance imaging.

Sparganosis is a rare parasitic infection affecting various organs, including the central nervous system, especially the lumbar epidural space. This report describes the identification of disease and different strategies of treatments with preoperative information. A 42-year-old man presented with a 2-year history of urinary incontinence and impotence. He had a history of ingesting raw frogs 40 years ago. Magnetic resonance (MR) imaging showed an intramedullary nodular mass at conus medullaris and severe inflammation in the cauda equina. A 51-year-old woman was admitted with acute pain in the left inguinal area. We observed a lesion which seemed to be a tumor of the lumbar epidural space on MR imaging. She also had a history of ingesting inadequately cooked snakes 10 years ago. In the first patient, mass removal was attempted through laminectomy and parasite infection was identified during intra-operative frozen biopsy. Total removal could not be performed because of severe arachnoiditis and adhesion. We therefore decided to terminate the operation and final histology confirmed dead sparganum infection. We also concluded further surgical trial for total removal of the dead worm and inflammatory grannulation totally. However, after seeing another physician at different hospital, he was operated again which resulted in worsening of pain and neurological deficit. In the second patient, we totally removed dorsal epidural mass. Final histology and enzyme-linked immunosorbent assay (ELISA) confirmed living sparganum infection and her pain disappeared. Although the treatment of choice is surgical resection of living sparganum with inflammation, the attempt to remove dead worm and adhesive granulation tissue may cause unwanted complications to the patients. Therefore, the result of preoperative ELISA, as well as the information from image and history, must be considered as important factors to decide whether a surgery is necessary or not.

Degenerative lumbar scoliosis is a coronal deviation of the spine that is prevalent in the elderly population. Although the etiology is unclear, it is associated with progressive and asymmetric degeneration of the disc, facet joints, and other structural spinal elements typically leading to neural element compression. Clinical presentation varies and is frequently associated with axial back pain and neurogenic claudication. Indications for treatment include pain, neurogenic symptoms, and progressive cosmetic deformity. Non-operative treatment includes physical conditioning and exercise, pharmacological agents for pain control, and use of orthotics and invasive modalities like epidural and facet injections. Operative treatment should be contemplated after multi-factorial and multidisciplinary evaluation of the risks and the benefits. Options include decompression, instrumented stabilization with posterior or anterior fusion, correction of deformity, or a combination of these that are tailored to each patient. Incidence of perioperative complications is substantial and must be considered when deciding appropriate operative treatment. The primary goal of surgical treatment is to provide pain relief and to improve the quality of life with minimum risk of complications.

Spinal epidural lipomatosis (SEL) is an overgrowth of the normally encapsulated adipose tissue in the epidural space around the spinal cord in the thoracic and lumbar spine causing compression of the neural components. Idiopathic SEL in non-obese patients is exceptional. Idiopathic SEL can result in thoracic myelopathy and lumbar radiculopathy. A thoracic radiculopathy due to idiopathic SEL has not been reported yet. We report a case of idiopathic SEL with intractable chest pain and paresthesia. We suggest that idiopathic SEL should be considered as a cause of chest pain.

Degenerated conditions such as herniated disc or spinal stenosis are common etiologies of lumbar radiculopathy. Less common etiologies include spinal extradural cyst such as synovial cysts and ganglion cysts. Ganglion cyst of the posterior longitudinal ligament (PLL) of the spine is a rare entity that can result in classical sciatica. Posterior longitudinal ligament cyst has no continuity with the facet joint and has no epithelial lining. Two young male patients presented with unilateral sciatica and were found to have intraspinal cystic lesions causing lumbar radiculopathy. Magnetic resonance imaging demonstrated rounded, cystic lesions (i.e., hypointense on T1- but hyperintense on T2-weighted images) adjacent to minimally dehydrated, nonherniated disc spaces in both cases. These patients underwent posterior decompression and cysts were excised, and their sciatic symptoms were completely resolved. Histological examination showed typical features of ganglion cysts in these cases.

Among the multiple causes of chronic low back pain, axial and discogenic pain are common. Various modalities of treatments are utilized in managing discogenic and axial low back pain including epidural injections. However, there is a paucity of evidence regarding the effectiveness, indications, and medical necessity of any treatment modality utilized for managing axial or discogenic pain, including epidural injections. In an interventional pain management practice in the US, a randomized, double-blind, active control trial was conducted. The objective was to assess the effectiveness of lumbar interlaminar epidural injections of local anesthetic with or without steroids for managing chronic low back pain of discogenic origin. However, disc herniation, radiculitis, facet joint pain, or sacroiliac joint pain were excluded. Two groups of patients were studied, with 60 patients in each group receiving either local anesthetic only or local anesthetic mixed with non-particulate betamethasone. Primary outcome measures included the pain relief-assessed by numeric rating scale of pain and functional status assessed by the, Oswestry Disability Index, Secondary outcome measurements included employment status, and opioid intake. Significant improvement or success was defined as at least a 50% decrease in pain and disability. Significant improvement was seen in 77% of the patients in Group I and 67% of the patients in Group II. In the successful groups (those with at least 3 weeks of relief with the first two procedures), the improvement was 84% in Group I and 71% in Group II. For those with chronic function-limiting low back pain refractory to conservative management, it is concluded that lumbar interlaminar epidural injections of local anesthetic with or without steroids may be an effective modality for managing chronic axial or discogenic pain. This treatment appears to be effective for those who have had facet joints as well as sacroiliac joints eliminated as the pain source.

Although the most common aetiology of cauda equina lesions is lumbar intervertebral disc herniation, iatrogenic lesions may also be the cause. The aim of this study was to identify and present patients in whom cauda equina lesions occurred after spinal surgery. From the author’s series of patients with cauda equina lesions, those with the appearance of sacral symptoms after spinal surgery were identified. To demonstrate lesions more objectively, electrodiagnostic studies were performed in addition to history and clinical examination. Imaging studies were also reviewed. Of 69 patients from the series, 11 patients in whom a cauda equina lesion developed after spinal surgery were identified. The aetiology comprised surgery for herniated intervertebral disc in 5 (4 performed by a single surgeon), spinal stenosis surgery in 4, and postoperative lumbar epidural haematoma in 2 patients (each performed by a different surgeon). Proportion of spinal surgeries with this complication varied from 0 to 6.6‰ in different centres. Patients with iatrogenic cauda equina lesion were significantly older (p < 0.001), and reported more severe urinary, but similar bowel and sexual symptoms compared to other patients in the series. In conclusion the study identified spinal surgery as the cause of approximately 15% of cauda equina lesions. More than a third of lesions developed after procedures performed by a single surgeon. Most of the remaining lesions could probably be avoided by better surgical technique (e.g. the use of a high-speed drill instead of a Kerrison rongeur in patients with severe spinal stenosis), or prevented by closer postoperative monitoring (e.g. in patients with postoperative lumbar epidural haematoma).

Study design

Case-series study.

Objective

To describe the clinical presentation, characteristic findings of imaging studies, and treatment of lumbar radiculopathy caused by foraminal stenosis in rheumatoid arthritis.

Background

Lumbar lesions in rheumatoid arthritis are relatively rare, with a limited number of systemic reports.

Methods

Six patients with lumbar radiculopathy caused by foraminal stenosis in rheumatoid arthritis were treated. The patients were all women with a mean age of 69 years and mean rheumatoid arthritis duration of 15 years. The medical records and imaging studies of all patients were reviewed.

Results

The affected nerve roots were L4 in four patients and L3 in two patients. Foraminal stenosis was not demonstrated in magnetic resonance images in four of the six patients. Selective radiculography with nerve root block reproduced pain, manifested blocking effect, and demonstrated compression of the nerve root by the superior articular process of the lower vertebra in all patients. Conservative treatment was performed on one patient, and surgery was conducted for the rest of the five patients; radiculopathy was improved in all patients.

Conclusions

Lumbar foraminal stenosis is a characteristic pathology of rheumatoid arthritis, and should be kept in mind in the diagnosis of lumbar radiculopathy. Selective radiculography is useful in the diagnosis of affected nerve roots.

We report here on an uncommon case of metastatic choriocarcinoma to the lung, brain and lumbar spine. A 33-year-old woman was admitted to the pulmonary department with headache, dyspnea and hemoptysis. There was a history of cesarean section due to intrauterine fetal death at 37-weeks gestation and this occurred 2 weeks before admission to the pulmonary department. The radiological studies revealed a nodular lung mass with hypervascularity in the left upper lobe and also a brain parenchymal lesion in the parietal lobe with marginal bleeding and surrounding edema. She underwent embolization for the lung lesion, which was suspected to be an arteriovenous malformation according to the pulmonary arteriogram. Approximately 10 days after discharge from the pulmonary department, she was readmitted due to back pain and progressive paraparesis. The neuroradiological studies revealed a hypervascular tumor occupying the entire L3 vertebral body and pedicle, and the tumor extended to the epidural area. She underwent embolization of the hypervascular lesion of the lumbar spine, and after which injection of polymethylmethacrylate in the L3 vertebral body, total laminectomy of L3, subtotal removal of the epidural mass and screw fixation of L2 and L4 were performed. The result of biopsy was a choriocarcinoma.

Neurological deficits following epidural or spinal anesthesia are extremely rare. Transient paraplegia following epidural anesthesia in a patient with thoracic disc herniation has been presented. A 44-year-old woman developed paraplegia during the operation for vascular surgery of her legs under epidural anesthesia. Epidural hematoma or spinal cord ischemia was ruled out by magnetic resonance imaging of the thoracic and lumbar spine in which protruded disc at T11-12 level compressing the spinal cord has been verified. Patient responded well to steroid treatment and rehabilitation interventions. Physicians should be aware of preceding disc protrusions, which may have detrimental effects on spinal cord perfusion, as a cause of persistent or transient paraplegia before epidural anesthesia procedure. MRI is a valuable imaging option to rule out epidural anesthesia complications and coexisting pathologies like disc herniations.

A 53-year-old man had chronic low back and leg pain for four years without any history of trauma or neurological manifestations. There was a reduction in symptoms after a lumbar epidural block. Two hours later after the procedure, the patient complained of perineal numbness and lower extremity weakness. The neurological evaluation revealed loss of sensation in the saddle area and the posterior aspect of the leg. The deep-tendon reflexes were decreased in the leg. The patient was unable to urinate. The MRI revealed a schwannoma at the S3 level of the sacral spine with cauda equina compression. The patient's symptoms improved slightly over the next few hours. The patient had a gradual return of motor function and could feel the Foley catheter. All of the symptoms completely resolved over the next nine hours and the patient was discharged to home once completely recovered. This case illustrates the importance of clinical examination and continued vigilance for evaluation of neurological deterioration after epidural injections.

Degenerative disc disease (DDD) causes gradual intervertebral space collapse, concurrent discogenic or facet-induced pain, and possible compression radiculopathy. A new minimal invasion procedure of percutaneous posterior-lateral lumbar interbody fusion (PPLIF) using a B-Twin stand-alone expandable spinal spacer (ESS) was designed to treat this disease and evaluated by follow-up more than 1 year. 12 cases with chronic low back pain and compressive radiculopathy due to DDD refractory were selected to conservative treatment. Under fluoroscopy in the posterior-lateral position, a K-wire was advanced into the intervertebral space and a dilator and working cannula were introduced into the disc space step by step. Discectomy and endplate scratching were performed through the cannula using pituitary forceps and endplate curettage. An ESS was inserted into the intervertebral space by a B-Twin expandable spinal delivery system after some bone graft chips implanted into the disc space. The ongoing study includes intraoperative difficulties, complications, radiologic evidence of fusion and clinical outcome as scored by pre- and postoperative questionnaires pertaining to pain intensity and degree of disability. The 12 procedures of lumbar interbody fusion using stand-alone expandable spinal system through percutaneous approach were successful. Radiologic study demonstrated fusion in a total of 11 cases and only 1 exception after more than 1 year visiting. The values of Visual Analog Scale (VAS) on movement and Oswestry Disability Index (ODI) dropped by more than 80 and 67.4%, respectively. Disk space heights averaging 9.0 mm before procedure were increased to 11.5 mm 1 month (a significant difference compared with preprocedure, P < 0.01) after surgery and stabilized at 10.8 mm upon final follow-up (a significant difference compared with preprocedure, P < 0.01). The results demonstrated that the percutaneous approach for posterior-lateral lumbar interbody fusion using expandable spinal system is a valuable micro-invasion method for the DDD patients and can achieve the same outcome as with other methods.

Surgical excision was performed on a 30-years old woman with a painful mass on her left thigh. The pathologic findings on the mass indicated fibromatosis. After the operation, she complained of allodynia and spontaneous pain at the operation site and ipsilateral lower leg. We treated her based on postoperative femoral neuropathy, but symptom was aggravated. We found a large liposarcoma in her left iliopsoas muscle which compressed the lumbar plexus. In conclusion, the cause of pain was lumbar plexopathy related to a mass in the left iliopsoas muscle. Prompt diagnosis of acute neuropathic pain after an operation is important and management must be based on exact causes.

Reduction of blood flow in compressed nerve roots is considered as one important mechanism of induction of neurogenic intermittent claudication in lumbar spinal canal stenosis. Vascular endothelial growth factor (VEGF) is a potent stimulator of angiogenesis, and is increased in expression in hypoxic conditions. The objective of this study was to examine if cauda equina compression affects motor function and induces expression of VEGF and angiogenesis. The cauda equina was compressed by placing a piece of silicone rubber into the L5 epidural space. Walking duration was examined by rota-rod testing. The compressed parts of the cauda equina and L5 dorsal root ganglion (DRG) were removed at 3, 7, 14, or 28 days after surgery, and processed for immunohistochemistry for VEGF and Factor VIII (marker for vascular endothelial cells). Numbers of VEGF-immunoreactive (IR) cells and vascular density were examined. Walking duration was decreased after induction of cauda equina compression. The number of VEGF-IR cells in the cauda equina and DRG was significantly increased at 3, 14, and 28 days after cauda equina compression, compared with sham-operated rats (P < 0.05). Vascular density in the cauda equina was not increased at any of the time points examined. Cauda equina compression decreased walking duration, and induced VEGF expression in nerve roots and DRG.