Multiple primary intramedullary ependymomas: a case report and review of the literature

Background context

Intramedullary ependymomas constitute the most frequent type of intramedullary tumor. In patients with neurofibromatosis type 2 (NF2), multiple intramedullary ependymomas are known to occur. In the non-NF2 population, however, the presence of multiple synchronous intramedullary ependymomas is exceedingly rare.

Purpose

In this article, the authors report the second case in the literature of multiple primary synchronous intramedullary ependymomas. To the best of the authors knowledge, this report represents the first to provide a detailed pathology of all lesions, thereby giving an added level of confidence on the primary synchronous nature of the lesions. The authors have also performed a review of the literature regarding multifocal intramedullary ependymomas.

Study design

A review article and case report.

Conclusions

The concomitant localization of two primary intramedullary spinal cord ependymomas in the setting of nongenetic predisposition is an uncommon phenomenon. In this article, the authors present the second report of multiple, synchronous intramedullary ependymomas. A detailed review of the literature reveals that the presence of multiple intramedullary lesions in non-NF2 patients is both rare and deserving of further study.     

Improvement in pain after lumbar surgery in cancer patients with mechanical radiculopathy

Background context

Lumbar metastases can result in spinal instability and mechanical radiculopathy, characterized by radicular pain produced by axial loading. This pain pattern represents a definitive symptom of neoplastic instability and may serve as a reliable indication for surgical stabilization.

Purpose

We examined the results of surgical decompression and fixation in the treatment of mechanical radiculopathy.

Study design/setting

A retrospective clinical study.

Patient sample

An internally maintained spine neurosurgery database was queried between February 2002 and April 2010. Patients were identified and deemed eligible for inclusion in this study based on the presence of all the following: metastatic tumor, lumbar surgery, and lumbar radiculopathy.

Outcome measures

Visual analog scale (VAS) of pain and Eastern Cooperative Oncology Group (ECOG) status.

Methods

The Memorial Sloan-Kettering Cancer Center Department of Neurosurgery operative database was queried over an 8-year period to identify all patients with spinal metastases who underwent lumbar surgery. Only patients whose operative indication included mechanical radiculopathy were included. Pre- and postoperative pain was assessed with the VAS of pain, whereas pre- and postoperative performance status was evaluated using the ECOG.

Results

Fifty-five patients were included in the cohort. L2 and L3 were the most common levels involved, and most patients underwent multilevel posterior decompression and instrumented fusion. After surgery, 98% of patients reported pain relief. A significant difference between average pre- and postoperative pain scores was found (p<.01). Overall, 41.5% of patients experienced improvement in their ECOG score postoperatively.

Conclusions

Mechanical radiculopathy in patients with spinal metastases represents a highly reliable surgical indication. Spinal decompression and fixation is an effective treatment for pain palliation in this patient population.     

Intramedullary arachnoid cyst in association with cervical spondylosis: case report

Background context

Intramedullary spinal arachnoid cysts are considered to be very rare, and only 11 cases have been reported previously. Development of such a cyst in association with marked cervical spondylosis has not been reported until recently.

Purpose

Brief review of reported cases and debate on likely treatment strategy when such a cyst is associated with symptomatic spondylosis.

Study design

To report the first example of a cervicothoracic intramedullary arachnoid cyst along with a symptomatic cervical spondylosis.

Methods

Evaluation of quadriparesis in a 58-year-old female resulted in detection of a cervical spondylotic stenosis that was accompanied with an intramedullary cystic lesion. Parallel management of both pathologies was through a wide laminectomy extending from the lower edge of C3 to T2 with subsequent fenestration and partial resection of the cyst wall via an appropriate dorsal entry root zone myelotomy. Cervicothoracic instrumentation from C3 down to T2 was done to prevent postlaminectomy deformity.

Result

Histopathological findings were consistent with the diagnosis of arachnoid cyst. Postoperatively, the patient exhibited marked improvement in neurologic status.

Conclusion

Through the review of the current case, first example from the literature, we concluded that surgery should target toward the proper management of both pathologies in a single-stage operation.     

Huge thoracolumbar extradural arachnoid cyst excised by recapping T-saw laminoplasty

Background context

Spinal extradural arachnoid cysts are rare expanding lesions in the spinal canal. Total removal of the cyst and repair of the dural defect is the primary treatment for symptomatic spinal extradural arachnoid cysts.

Purpose

To report the usefulness of recapping T-saw laminoplasty in treating huge extradural arachnoid cyst.

Study design

Case report.

Methods

We report the case of a 43-year-old man who presented with a 2-year history of progressive muscle weakness and numbness of the lower extremities. Magnetic resonance imaging (MRI) showed a huge extradural arachnoid cyst at the T12–L3 level extending into bilateral neural foramina and severe posterior compression of the spinal cord and cauda equina.

Results

The patient underwent total resection of the cyst and closure of the communication. En bloc recapping T-saw laminoplasty of T12–L2 including the T12–L1 and L1–L2 facet joints was performed to obtain extensive exposure and preserve posterior stability. Postoperatively, the patient achieved complete recovery of neurologic functions. Follow-up MRI demonstrated no recurrence of the cyst. Bone union after laminoplasty was obtained within 6 months.

Conclusion

Total resection of the cyst and closure of the communication is curative for this rare lesion. Recapping T-saw laminoplasty provides extensive exposure for removal of a large cyst while allowing complete preservation of the posterior spinal elements.     

Decompression of peripheral nerve trunks in leprosy to prevent the development and progression of deformities

Background:

Peripheral nerve involvement results in deformities in leprosy. High doses (40-60 mg) of steroids along with anti-leprosy drugs is the preferred treatment, even though 70-75% cases still develop deformity. Early surgical decompression of nerves gives better chances of preventing deformity. We have analyzed the role of early surgical decompression in such cases.

Materials and Methods:

Five hundred nerves (386 ulnar, 60 median and 54 posterior tibial) not responding to the medical treatment in 12 weeks, were undertaken for external and internal nerve trunk decompression. These cases were followed up for five to 20 years at various intervals.

Results:

The pain in nerve (neuralgia) recovered in all cases of ulnar, median and posterior tibial nerves. Full sensory recovery to pinprick and feather or cotton wool touch was seen in 50% cases of all the three nerves. Twenty percent cases maintained the preoperative levels of sensory status. Plantar ulcers healed within six months after decompression of posterior tibial nerve but six cases showed recurrence. Overall motor recovery in ulnar nerve was 89% and 70% in median nerve.

Conclusions:

The sensory recovery restores protective sensation which prevents secondary injuries. The improvement of motor power gives better function and improves the appearance, which in the absence of surgical intervention was not possible.     

Adjacent segment disease in the lumbar spine following different treatment interventions

Background context

Adjacent segment disease (ASD) is symptomatic deterioration of spinal levels adjacent to the site of a previous fusion. A critical issue related to ASD is whether deterioration of spinal segments adjacent to a fusion is due to the spinal intervention or due to the natural history of spinal degenerative disease.

Purpose

The purpose of this review is to summarize the recent clinical literature on adjacent segment disease in light of the natural history, patient-modifiable risk factors, surgical risk factors, sagittal balance, and new technology.

Study design

This review will evaluate the recent literature on genetic and hereditary components of spinal degenerative disease and potential links to the development of ASD.

Methods

After a meticulous search of Medline for relevant articles pertaining to our review, we summarized the recent literature on the rate of ASD and the effect of various interventions, including motion preservation, sagittal imbalance, arthroplasty, and minimally invasive surgery.

Results

The reported rate of ASD after decompression and stabilization procedures is approximately 2% to 3% per year. The factors that are consistently associated with adjacent segment disease include laminectomy adjacent to a fusion and a sagittal imbalance.

Conclusions

Spinal surgical interventions have been associated with ASD. However, whether such interventions may lead to an acceleration of the natural history of the disease remains questionable.     

Detection of postoperative neurologic deficits using somatosensory-evoked potentials alone during posterior cervical laminoplasty

Background context

The use of neurophysiologic monitoring during anterior and posterior cervical decompression procedures in patients with spondylotic myelopathy remains controversial. The ideal neurophysiologic monitoring modality of choice is also highly debated.

Purpose

The purpose of this study was to evaluate the utility of neurophysiologic monitoring with only somatosensory-evoked potentials (SSEPs) in a consecutive series of laminoplasty procedures with regard to the detection of new postoperative neurologic deficits.

Study design

Retrospective case series.

Patient sample

Eighty consecutive patients who underwent a posterior cervical laminoplasty were reviewed.

Outcome measures

We analyzed intraoperative SSEP amplitude and latency changes from baseline with regard to the development of new postoperative neurologic deficits.

Methods

We retrospectively reviewed 80 patients who underwent a posterior cervical “open-door” laminoplasty with a standard SSEP neurophysiologic monitoring protocol. Intraoperative SSEP amplitude and latency changes from baseline (“alerts”) were analyzed with regard to the development of new postoperative neurologic deficits.

Results

Baseline SSEP values were obtained in all patients. There were five (6%) procedures that had SSEP alerts. All alerts occurred shortly after the lamina was hinged open. Four patients with SSEP alerts developed new postoperative neurologic deficits, including three unilateral upper extremity motor and sensory deficits and one complete spinal cord injury. In the immediate postoperative period, our experience with SSEP monitoring demonstrated 4 true-positive, 75 true-negative, and 1 false-positive monitoring results.

Conclusions

In this series of laminoplasty procedures, SSEP neurophysiologic monitoring had a high sensitivity and specificity for predicting new neurologic deficits in the early postoperative period. Somatosensory-evoked potentials are an effective tool for spinal cord monitoring when performing a posterior cervical laminoplasty procedure.     

Frequent neuromonitoring loss during the completion of vertebral column resections in severe spinal deformity surgery

Background Context

Intraoperative monitoring (IOM) is an essential method for preventing postoperative spinal deficits during posterior vertebral column resection (VCR) surgery for treatment of severe spine deformities, but the IOM features directing at VCR procedures are rarely reported and need to be further clarified.

Forearm post-traumatic deformities: Classification and treatment

Introduction

There is no classification for acquired forearm deformities. A clinical-radiographic study was conducted to classify these deformities and evaluate the results.

Materials and methods

Thirteen patients with forearm deformities following traumas or their treatment were included (11 men and two women, from 2000 to 2010). Mean age was 31 years (range 10–75 years). Initial treatment was conservative in five patients and surgical in eight patients. One segment was affected in seven patients (the radius in four patients, the ulna in three), and both segments were affected in six patients. Location assessment: 2 projections X-rays, including wrist and elbow. Deformity location: proximal, diaphisary, distal, defined with the abbreviation, in distal sense, R1, R2, R3 for the radius, and U1, U2, U3 for the ulna. Primary and secondary deformities were distinguished: secondary deformities occurred later in a different location than the primary one. Six patients were treated with plate and screws. An external fixator was used in six patients. One patient was treated with bone resection. Iliac crest bone graft was used in 10 patients, and vascularised fibula graft in one patient.

Results

The primary deformity affecting the radial diaphysis (R2) determined a secondary deformity in four patients: in the distal ulna (U3) with ulnocarpal dislocation in three patients and in the distal radius (R3) in one patient. Results of osteosynthesis treatment were excellent in one patient, satisfactory in four and unsatisfactory in one. External fixation was excellent in one patient and satisfactory in five. Bone resection was satisfactory in one patient.

Discussion

Surgical treatments with osteosynthesis are the major cause of acquired forearm deformities in adults. Location and aetiology of the deformities are essential for the surgical indication and the result. It is important to restore the length of the deformed segment, realigning the anatomical axis. X-rays enable clinicians to distinguish between primary and secondary forearm deformities.

Conclusion

Characteristics and locations of post-traumatic deformities were identified. The major location is diaphisary and distal, the elbow is rarely affected. The functional consequence is a limitation in the range of motion of the hand. The best results are achieved with short-term treatment.     

Primary cervical amyloidoma: a case report and review of the literature

Background context

Primary solitary amyloidosis or amyloidoma is a disease process characterized by the focal deposition of amyloid in the absence of a plasma cell dyscrasia with normal serum protein measurements. Solitary amyloidomas affecting the vertebrae are very uncommon but typically affect the thoracic spine. Primary cervical amyloidosis is an exceedingly rare entity with exceptionally good prognosis, but requires diligence of the treating physician to establish the diagnosis and implement the appropriate surgical intervention.

Purpose

This study aimed to present a rare case of primary cervical amyloidosis with long-term follow-up and review the clinical presentation, characteristic imaging findings, diagnostic pathology, differential diagnosis, treatment algorithm, and prognosis of the disease entity. This case demonstrates the progressive resorption of the amyloidoma over time after surgical stabilization. Previous reported cases of primary cervical amyloidosis will also be reviewed.

Study design

This study is a report and review of the literature.

Methods

A 77-year-old woman presented with a several-week history of gradual progressive weakness in her upper and lower extremities. Computed tomography and magnetic resonance imaging demonstrated a retro-odontoid nonenhancing soft-tissue mass, with erosive bony changes and severe mass effect on the upper cervical cord. The patient was taken to the operating room for decompression and posterior spinal stabilization.

Results

Intraoperative tissue specimens demonstrated amyloidosis and extensive systemic workup did not reveal any inflammatory processes, systemic amyloidosis, or plasma cell dyscrasia. Postoperatively, the patient regained full strength and ambulatory status. The patient remains asymptomatic at a 2-year follow-up. A postoperative follow-up magnetic resonance imaging demonstrated complete resorption of the residual amyloidoma.

Conclusions

Primary solitary amyloidosis is a rare form of amyloidosis that is important to differentiate given its excellent prognosis with surgical management. Treatment should include surgical decompression and spinal stabilization. This is the first case report to clinically and radiographically demonstrate the progressive resorption of a primary amyloidoma over time after surgical stabilization in the upper cervical spine. It is imperative that surgeons encountering such lesions maintain a high suspicion for this rare disease entity and advise their pathologists accordingly to establish the correct diagnosis.     

The use of spinal angiography in the management of posterior mediastinal tumors: Case series and review of the literature

Introduction

Resection of inferiorly located posterior mediastinal tumors can be complicated by their proximity to the artery of Adamkiewicz (AKA). Although uncommon, intraoperative injury to the AKA may result in paraparesis or paralysis secondary to spinal cord ischemia. The use of preoperative spinal angiography may serve as a useful adjunct to the surgeon in guiding extent of resection of the tumor to avoid injury to this critical artery.

Methods

After IRB approval (H-31712), three patients, from 2008 to 2011, with lower posterior mediastinal tumors were identified. Their charts were reviewed for information concerning preoperative imaging, operative details, and postoperative neurologic complications. The literature regarding imaging of the AKA, cases of injury in pediatric patients, and recommendations for treatment after its injury were reviewed.

Results

One patient, who did not have preoperative spinal angiography, developed transient paresis lasting 6 weeks after posterior mediastinal tumor resection. Two patients underwent preoperative spinal angiography with successful localization of the AKA. In both cases, the patients subsequently underwent posterior mediastinal tumor resection without injury to the artery and without postoperative neurologic sequelae.

Conclusions

Preoperative spinal angiography may serve as a useful adjunct in the evaluation of children with inferior posterior mediastinal tumors in order to delineate the relationship of the artery of Adamkiewicz to the tumor for the purpose of guiding surgical resection.     

Reoperation rate after surgery for lumbar spinal stenosis without spondylolisthesis: a nationwide cohort study

Background context

Lumbar spinal stenosis is one of the most common degenerative spine diseases. Surgical options are largely divided into decompression only and decompression with arthrodesis. Recent randomized trials showed that surgery was more effective than nonoperative treatment for carefully selected patients with lumbar stenosis. However, some patients require reoperation because of complications, failure of bony fusion, persistent pain, or progressive degenerative changes, such as adjacent segment disease. In a previous population-based study, the 10-year reoperation rate was 17%, and fusion surgery was performed in 10% of patients. Recently, the lumbar fusion surgery rate has doubled, and a substantial portion of the reoperations are associated with a fusion procedure. With the change in surgical trends, the longitudinal surgical outcomes of these trends need to be reevaluated.

Purpose

To provide the longitudinal reoperation rate after surgery for spinal stenosis and to compare the reoperation rates between decompression and fusion surgeries.

Study design/setting

Retrospective cohort study using national health insurance data.

Patient sample

A cohort of patients who underwent initial surgery for lumbar stenosis without spondylolisthesis in 2003.

Outcome measures

The primary end point was any type of second lumbar surgery. Cox proportional hazards regression modeling was used to compare the adjusted reoperation rates between decompression and fusion surgeries.

Methods

A national health insurance database was used to identify a cohort of patients who underwent an initial surgery for lumbar stenosis without spondylolisthesis in 2003; a total of 11,027 patients were selected. Individual patients were followed for at least 5 years through their encrypted unique resident registration number. After adjusting for confounding factors, the reoperation rates for decompression and fusion surgery were compared.

Results

Fusion surgery was performed in 20% of patients. The cumulative reoperation rate was 4.7% at 3 months, 7.2% at 1 year, 9.4% at 2 years, 11.2% at 3 years, 12.5% at 4 years, and 14.2% at 5 years. The adjusted reoperation rate was not different between decompression and fusion surgeries (p=.82). The calculated reoperation rate was expected to be 22.9% at 10 years.

Conclusions

The reoperation rate was not different between decompression and fusion surgeries. With current surgical trends, the reoperation rate appeared to be higher than in the past, and consideration of this problem is required.     

Intratumoral hemorrhage because of primary spinal mixed germ cell tumor presenting with atypical radiological features in an adult

Background context

Germ cell tumors are known to arise in the central nervous system, usually in the intracranial regions. However, primary spinal mixed germ cell tumors are extremely rare.

Purpose

This is the first reported case of intratumoral hemorrhage because of a primary spinal mixed germ cell tumor consisting of germinoma and immature teratoma in the conus medullaris of an adult patient that presented with rapid changes on magnetic resonance image (MRI). We report this rare case and discuss the clinical manifestations of an intramedullary spinal mixed germ cell tumor in adult.

Study design

A case report.

Methods

A 42-year-old woman experienced buttock numbness, and a spinal cord tumor was observed on the conus medullaris on MRI. The patient was scheduled for an operation in 1 month, but she developed sudden-onset neurologic deterioration. Rapid progression of the tumor was observed on follow-up MRI. The tumor was removed by emergency surgery and was identified as a primary mixed germinoma and immature teratoma.

Results

The patient received adjuvant chemotherapy and radiotherapy after gross total resection. The neurologic deficit of the patient was relieved, and recurrence of the tumor was not observed 26 months after the surgery.

Conclusions

We present this rare case and emphasize the necessity of precise diagnosis and early treatment of primary spinal germ cell tumor. Close observation on MRI is required after surgery, and adjuvant chemotherapy and radiotherapy should be considered according to the pathologic features.     

Progressive severe kyphosis as a complication of multilevel cervical percutaneous facet neurotomy: a case report

Background context

Percutaneous facet neurotomy is a procedure commonly used for the treatment of pain thought to originate from zygoapophyseal joint dysfunction. Some practitioners have also used this technique to treat cervicogenic headache. Previously reported complications for this procedure have been minimal and have included dysthesias and local pain.

Study design

Case report.

Methods

Bilateral multilevel cervical percutaneous facet neurotomies were used to treat a patient suffering from a chronic headache and neck pain that had failed to respond to extensive medical management.

Results

Within days of completing the bilateral facet neurotomies, the patient developed head drop. Subsequent electromyography revealed denervation of the patient's paraspinous muscles. Initially the patient was managed conservatively in a cervical collar with the hope that he would recover some function. After few years, the patient developed fixed kyphotic deformity. Correction of the patient's deformity required multilevel anterior cervical discectomy and fusion followed by posterior instrumented fusion.

Conclusions

When performing multilevel percutaneous cervical facet neurotomies, there is a risk of paraspinous muscle denervation, and subsequent kyphotic deformity may occur. The likelihood of this rare and previously unreported complication can probably be reduced by proper needle positioning and by minimizing the number of levels at which the procedure is performed.     

A rare case of osteoblastoma combined with severe scoliosis deformity,coronal and sagittal imbalance

Background

Osteoblastoma is a rare and benign tumor which requires early diagnosis and surgical excision. Scoliosis is a common presentation following osteoblastoma. It is considered due to pain-provoked muscle spasm on the side of the lesion. Few researches about osteoblastoma combined with severe scoliosis have been reported.

Case presentation

A 14-year-old girl presents with progressive scoliosis deformity for 3 years, with gradually appeared low back pain and numbness of left leg. Radiographic results showed osteoblastic mass at the left side of L3-L4 with severe scoliosis deformity, pelvic obliquity and spinal imbalance. The patient underwent posterior tumor excision, spinal decompression, scoliosis correction, spinal fusion with auto-graft and instrumentation from T8-S1. The mass was found to be osteoblastoma. The patient had a full neurological recovery with no aggravate of scoliosis or spinal imbalance during the follow-up.

Conclusions

This case emphasizes the importance of early diagnosis and surgical treatment of osteoblastoma. Early surgical excision will not only prevent neurological deficit but also the progression of scoliosis. Atypical scoliosis presence without pain requires carefully examination of whether a tumor exists.

     

Fracture of the proximal phalanx of the little finger in children: a classification and a method to measure the deformity

Objective

To develop an improved method for measuring the deformity caused by fracture of the proximal end of the proximal phalanx of the little finger in children.

Design

A prospective case study.

Setting

Regional hospitals with an orthopedic service.

Patients

Forty-two children with a proximal phalangeal fracture of the little finger and 42 children without a phalangeal fracture, who acted as a control. The type of deformity resulting from the fracture was noted, and the angle of deformity was measured. Rotational deformities were measured clinically in all patients and angulation deformities were measured from radiographs. The deformities were graded and classified.

Main outcome measures

Measurements of the fracture deformity before and after manipulation.

Results

There were 38 ulnar angulation deformities, 26 dorsal angulation deformities, 10 ulnar rotation deformities, 3 palmar angulation deformities, 2 radial angulation deformities and 1 radial rotation deformity. The deformities could be graded into 6 different types.

Conclusion

The measurements of deformity made it possible to describe and classify isolated deformities and combinations of various deformities.     

Spinal Glioblastoma Multiforme: Unusual Cause of Post-Traumatic Tetraparesis

Background/Objective:

Glioblastoma multiforme (GBM) is the most common glial cell tumor of the adult brain. However, primary GBM of the spinal cord is a rare condition.

Methods:

Case report.

Results:

A young man presented with acute onset quadriparesis after a whiplash injury. A magnetic resonance scan showed the typical appearance of a high-grade intramedullary tumor with fusiform expansion of the entire cervical cord. Subtotal decompression and biopsy was done by posterior laminectomy, followed by external beam radiotherapy. Signs and symptoms improved after the completion of radiotherapy but did not resolve completely. Death caused by respiratory failure occurred 3 months later.

Conclusions:

This presentation of GBM of the cervical cord is rare; an intramedullary tumor should be considered when minor cervical trauma results in disproportionate neurologic deficit. To the best of our knowledge, this is the first reported case of spinal GBM with extensive pan-cervical involvement.     

Microscopic anterior foraminal decompression combined with anterior lumbar interbody fusion

Background context

Anterior lumbar interbody fusion (ALIF) with percutaneous pedicle screw fixation (PPF) provides successful surgical outcomes to isthmic spondylolisthesis patients with indirect decompression through foraminal volume expansion. However, indirect decompression through ALIF followed by PPF may not obtain a successful surgical outcome in patients with isthmic spondylolisthesis accompanied by foraminal stenosis caused by a posterior osteophyte or foraminal sequestrated disc herniation. Thus far, there has been no report of foraminal decompression through anterior direct access in the lumbar spine.

Purpose

This study aims to describe the new surgical technique of microscopic anterior foraminal decompression and to analyze the clinical outcomes and radiologic results of the microscopic anterior decompression during ALIF followed by PPF.

Study design/Setting

We conducted a multisurgeon, retrospective, clinical series from a single institution.

Patient sample

This study was carried out from March 2007 to July 2010 and included 40 consecutive patients with isthmic spondylolisthesis accompanied by foraminal stenosis caused by posterior osteophyte or foraminal sequestrated disc herniation undergoing microscopic anterior foraminal decompression during ALIF followed by PPF.

Outcome measures

The visual analog scales (VAS) of back and leg pain and the Oswestry disability index were measured preoperatively and at the last follow-up.

Methods

Postoperative computed tomography and magnetic resonance imaging measured whether decompression of neural structure had been made and morphometric change of the foramen and the amount of resected bone. Moreover, segmental lordosis, whole lumbar lordosis, disc height, and degree of listhesis were measured through X-ray examination before the operation and at the last follow-up; we also verified whether fusion had been achieved.

Results

Successful decompression was confirmed in both patients with foraminal stenosis caused by posterior osteophyte and those with foraminal sequestrated disc herniation. Clinically, compared with before the surgery, the VAS (leg and back) and the Oswestry disability index significantly decreased at the last follow-up (p=.000). With regard to radiology, at the last follow-up all patients had bone fusion on X-ray examination, and an increase in disc height, a reduction in the degree of listhesis, an increase in segmental lordosis, and an increase in whole lumbar lordosis were significant in both groups (p=.000) compared with before the surgery. Foraminal volume, foraminal width, and foraminal height also significantly increased postoperatively compared with before the operation (p=.000). The height, width, and dimension of resected body were 4.61±1.05 mm, 7.92±1.42 mm, 17.15±4.96 mm², respectively, in patients with foraminal stenosis caused by a posterior osteophyte, and 3.88±0.92 mm, 6.8±1.29 mm, and 13.12±2.25 mm², respectively, in patients with foraminal sequestrated disc.

Conclusions

The microscopic anterior foraminal approach provides successful foraminal decompression. Combined with ALIF and PPF, this approach shows a good surgical outcome in patients with isthmic spondylolisthesis accompanied by foraminal stenosis caused by a posterior osteophyte or those with foraminal sequestrated disc herniation.     

Acute epidural lipedema: a novel entity and potential complication of bone morphogenetic protein use in lumbar spine fusion

Background context

Bone morphogenetic proteins (BMPs) induce osteogenesis, making them useful for decreasing time to union and increasing union rates. Although the advantages of BMP-2 as a substitute for iliac crest graft have been elucidated, less is known about the safety profile and adverse events linked to their use in spinal fusion. An accumulation of reactive edema in the epidural fat may lead to neural compression and significant morbidity after lumbar spinal fusion. Bone morphogenetic protein has never been implicated as a cause of spinal epidural lipedema.

Purpose

We report on a case of rapid accumulation of edematous adipose tissue in the epidural space after lumbar spine decompression and fusion with bone morphogenic protein.

Study design

Case report.

Methods

The patient was a 45-year-old woman with chronic back pain, worsening bilateral L5 radiculopathy, and degenerative disc disease. Surgery consisting of a one-level transpedicular decompression, transforaminal lumbar interbody fusion, and posterolateral fusion was performed using BMP-2 as an adjunct for arthrodesis.

Results

Two days postoperatively, the patient developed progressive cauda equina syndrome. Lumbar magnetic resonance imaging revealed edematous epidural fat extending above the initial laminectomy, compromising the spinal canal, and compressing the thecal sac. Emergent laminectomies at L3, L4, and L5 were performed, and intraoperative pathology revealed edematous epidural adipose tissue. The patient's cauda equina syndrome resolved after spinal decompression and the removal of epidural fat. Final cultures were negative for infection, and histology report yielded an accumulation of edematous fibroadipose tissue.

Conclusions

We present a case of rapid accumulation of edematous adipose tissue causing cauda equina syndrome after a lumbar decompression and fusion surgery. The acute nature and extensive development of the lipedema presented in this case indicate an intense inflammatory reaction. We hypothesize that there may be a link between the use of BMP-2 and the accumulation of this edematous tissue. A thorough understanding of the mechanisms of BMP-2 and specific guidelines for their role in spinal surgery may improve functional outcomes and reduce the number of preventable complications. To the best of our knowledge and after a thorough literature search, this is the only reported case of epidural lipedema causing cauda equina syndrome.