Delayed postoperative tethering of the cervical spinal cord

A Novel Untethering and Duraplasty Technique for Postsurgical Tethered Spinal Cord

Progressive post-traumatic postsurgical myelopathy (PPPM) is a known entity that can occur months to years after the initial insult. Symptomatic patients can become myelopathic and have rapid and progressive neurological decline. Surgical correction of PPPM usually involves intradural exploration and lysis of adhesions that carries the risk of further injury to the spinal cord. In this manuscript, we provide a report of a patient presenting more than 50 years after the initial resection of an intramedullary tumor. Additionally, we present and describe a novel surgical technique for managing this difficult problem and restoring normal CSF dynamics.

Posterior Surgical Approach for Ventral Cervical Spinal Cord Herniation: 2-Dimensional Operative Video

Spinal cord herniation (SCH) is a rare condition that is typically of idiopathic origin. Although SCH is mostly found in the thoracic region because of a dural defect, there are some reports of cervical SCH following surgery or trauma.1-3 Spinal cord tethering can be a result of SCH or as a standalone issue.4,5 These conditions can lead to progressive neurological deficits, including numbness, gait disturbances, and decreased muscle strength, requiring surgical correction. There are limited reports of surgical procedures for ventral SCHs. Several reports exist using a ventral approach for intradural tumors, but it is not commonly employed because of the inability to obtain adequate dural closure.6 Much of the literature on SCH comes from idiopathic and congenital cases in the thoracic spine.7,8 Posterior and posterolateral approaches for a ventral thoracic SCH have been described, as well as an anterior approach for a ventral cervical SCH.9-12 In this video, we describe a posterior approach for a ventral cervical SCH. A 38-yr-old male presented with progressive cervical myelopathy 9 yr after a C2-C3 schwannoma resection requiring an anterior approach and corpectomy of C3 with partial corpectomies of C2 and C4. A preoperative magnetic resonance imaging showed a ventrally herniated spinal cord at the top of the C3 vertebral body and below the C4 vertebral body. Informed consent was obtained. The posterior surgical approach involved a C1-C5 laminectomy, sectioning the dentate ligament, ventral cord untethering, removal of residual tumor, and placement of a ventral sling. A significant improvement in sensory and motor function was observed postoperatively.

Pediatric pathology all grown up - An interesting case of adult tethered spinal cord

Background:

Cervical myelopathy in an adult is typically the result of degenerative disease or trauma. Dysraphism is rarely the cause.

Case Description:

The authors report the case of a 35-year-old male drywall installer who presented with 2 years of progressive left upper extremity weakness, numbness, and hand clumsiness. Only upon detailed questioning did he mention that he had neck surgery just after birth, but he did not know what was done. He then also reported that he routinely shaved a patch of lower back hair, but denied bowel, bladder, or lower extremity dysfunction. Magnetic resonance imaging of the cervical spine demonstrated T2 hyperintensity at C4-C5 with dorsal projection of the neural elements into the subcutaneous tissues concerning for a retethered cervical myelomeningocele. Lumbar imaging revealed a diastematomyelia at L4. He underwent surgical intervention for detethering and repaired of the cervical myelomeningocele. Four months postoperatively, he had almost complete resolution of symptoms, and imaging showed a satisfactory detethering. The diastematomyelia remained asymptomatic and is being observed.

Conclusion:

Tethered cervical cord is a rare cause for myelopathy in the adult patient. In the symptomatic patient, surgical repair with detethering is indicated to prevent disease progression and often results in clinical improvement.

Origin of Syrinx Fluid in Syringomyelia: A Physiological Study

BACKGROUND

The origin of syrinx fluid is controversial.

OBJECTIVE

To elucidate the mechanisms of syringomyelia associated with cerebrospinal fluid pathway obstruction and with intramedullary tumors, contrast transport from the spinal subarachnoid space (SAS) to syrinx was evaluated in syringomyelia patients.

METHODS

We prospectively studied patients with syringomyelia: 22 with Chiari I malformation and 16 with SAS obstruction-related syringomyelia before and 1 wk after surgery, and 9 with tumor-related syringomyelia before surgery only. Computed tomography-myelography quantified dye transport into the syrinx before and 0.5, 2, 4, 6, 8, 10, and 22 h after contrast injection by measuring contrast density in Hounsfield units (HU).

RESULTS

Before surgery, more contrast passed into the syrinx in Chiari I malformation-related syringomyelia and spinal obstruction-related syringomyelia than in tumor-related syringomyelia, as measured by (1) maximum syrinx HU, (2) area under the syrinx concentration-time curve (HU AUC), (3) ratio of syrinx HU to subarachnoid cerebrospinal fluid (CSF; SAS) HU, and (4) AUC syrinx/AUC SAS. More contrast (AUC) accumulated in the syrinx and subarachnoid space before than after surgery.

CONCLUSION

Transparenchymal bulk flow of CSF from the subarachnoid space to syrinx occurs in Chiari I malformation-related syringomyelia and spinal obstruction-related syringomyelia. Before surgery, more subarachnoid contrast entered syringes associated with CSF pathway obstruction than with tumor, consistent with syrinx fluid originating from the subarachnoid space in Chiari I malformation and spinal obstruction-related syringomyelia and not from the subarachnoid space in tumor-related syringomyelia. Decompressive surgery opened subarachnoid CSF pathways and reduced contrast entry into syringes associated with CSF pathway obstruction.

Human Amniotic Membrane for the Prevention of Intradural Spinal Cord Adhesions: Retrospective Review of its Novel Use in a Case Series of 14 Patients

BACKGROUND

Tethering after spinal surgery is caused by adhesions that arise from intradural tissue manipulation. Microsurgical detethering is the only treatment for symptomatic patients, but retethering occurs commonly and no treatment is widely available to prevent this complication.

OBJECTIVE

To apply human amniotic membrane (HAM) grafts, which are immune-privileged and known to possess antifibrogenic properties, in patients requiring microsurgical detethering. For this first-in-human use, we evaluated the safety and potential efficacy of these grafts for preventing retethering.

METHODS

We retrospectively reviewed the medical records of all patients who required detethering surgery and received an HAM graft between 2013 and 2016 at our institution after various previous intradural spinal surgeries. In all 14 cases, intradural lysis of adhesions was achieved, an HAM graft was sewn in place intradurally, and a dural patch was closed in a watertight fashion over the graft.

RESULTS

Fourteen patients had received HAM grafts to prevent retethering. All patients had at least 6 mo of follow-up (mean follow-up, 14 mo). Retethering was noted in only 1 patient. Surgical re-exploration showed that the retethering occurred caudal to the edge of the HAM graft, with no tethering underneath the original graft. No complications were attributed specifically to the HAM graft placement.

CONCLUSION

This first-in-human series provides evidence that HAM grafts are a safe and potentially efficacious method for preventing retethering after microsurgical intradural lysis of adhesions. These results lay the groundwork for further prospective controlled trials in patients with this difficult-to-treat pathology.

Postoperative epidural hematoma contributes to delayed upper cord tethering after decompression of Chiari malformation type I

Background:

Symptomatic arachnoiditis after posterior fossa surgical procedures such as decompression of Chiari malformation is a possible complication. Clinical presentation is generally insidious and delayed by months or years. It causes disturbances in the normal flow of cerebrospinal fluid and enlargement of a syrinx cavity in the upper spinal cord. Surgical de-tethering has favorable results with progressive collapse of the syrinx and relief of the associated symptoms.

Case Description:

A 30-year-old male with Chiari malformation type I was treated by performing posterior fossa bone decompression, dura opening and closure with a suturable bovine pericardium dural graft. Postoperative period was uneventful until the fifth day in which the patient suffered intense headache and progressive loose of consciousness caused by an acute posterior fossa epidural hematoma. It was quickly removed with complete clinical recovering. One year later, the patient experienced progressive worsened of his symptoms. Upper spinal cord tethering was diagnosed and a new surgery for debridement was required.

Conclusions:

The epidural hematoma compressing the dural graft against the neural structures contributes to the upper spinal cord tethering and represents a nondescribed cause of postoperative fibrosis, adhesion formation, and subsequent recurrent hindbrain compression.

Tethering of the cervico-medullary junction with central cord oedema after foramen magnum decompression for Chiari malformation

An unusual complication following foramen magnum decompression for Chiari malformation is described: adhesive tethering of the cervico-medullary junction with oedema of the upper spinal cord and lower medulla. Further surgery was required to correct this condition.

Tethered cervical spinal cord due to a hamartomatous stalk in a young adult. Case report

The authors report on an unusual case of a congenital tethered cervical spinal cord in young man who presented with progressive tetraparesis. Neuroradiological evaluation of the spine revealed a discrete exophitic cervical spinal cord mass with a stalk of tissue that extended from the mass and terminated in the muscle tissue. The patient underwent a laminectomy with intradural exploration. A stalklike lesion was discovered and excised. Pathological examination showed that the stalk was formed of hamartomatous tissue. The patient improved following surgery, which suggested that tethering of the cervical spinal cord was responsible for his symptoms.

Anterior Cervical Spinal Cord Tethering after Anterior Spinal Surgery: Case Report

OBJECTIVE AND IMPORTANCE

This is the first reported case of anterior cervical spinal cord tethering after anterior spinal surgery. A mechanistic hypothesis is presented to explain the observed phenomenon.

CLINICAL PRESENTATION

A patient developed cervical myelopathy 2 years after multiple anterior cervical discectomies complicated by cerebrospinal fluid leakage. She demonstrated reflex and motor changes as well as neuropathic pain.

INTERVENTION

An anterior corpectomy was performed, with opening of the dura and detethering of an arachnoid band and then fusion and plating.

CONCLUSION

Reflex and motor changes improved, but pain did not. We hypothesize that mechanical deformation and scar formation after cerebrospinal fluid leakage may have led to tethering of the spinal cord.

Myotonic dystrophy presenting as new-onset hand weakness and recurrent pneumonia in a patient with paraplegia: A case reportaaNo commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors(s) or upon any organization with which the author(s) is/are associated

We describe a previously independent T11 paraplegic patient who had delayed-onset hand weakness and recurrent pneumonia caused by myotonic dystrophy. A man in his late thirties suffered a thoracic spinal cord injury (SCI) from a gunshot wound at the age of 17 years, with resultant T11 American Spinal Injury Association class A paraplegia. He lived independently until the age of 36 years when he was hospitalized multiple times for pneumonia. During a rehabilitation stay after one of the acute hospitalizations, the patient's hand weakness and diffuse muscular atrophy were noted. Electrodiagnostic testing was performed, which showed myotonic discharges. Genetic testing was consistent with myotonic dystrophy. This case shows the importance of considering causes of weakness that affect the population as a whole when evaluating a patient with SCI who presents with delayed-onset weakness.

EMG for assessing the recovery of voluntary movement after acute spinal cord injury in man

OBJECTIVE

Multi-channel electromyogram (EMG) was used to examine the pattern and time-course of voluntary contraction recovery in subjects with acute traumatic spinal cord injury (SCI), concentrating on the latest time after injury at which a given muscle would begin to show voluntary recruitment.

METHODS

We conducted repeated measures of voluntary contractions of 12 lower limb muscles (for all subjects) and 12 upper-limb muscles (for subjects with cervical injury), beginning within days of the injury and extending for 1 or more years post-injury. The EMG interference pattern was scored in a blinded fashion from tape records.

RESULTS

We recruited 229 subjects, including 152 from whom repeated measures were made. Several different patterns of recovery were identified. For persons with motor-incomplete injury to the cervical or thoracic spine, EMG recruitment had not yet occurred by 5 weeks post-injury in roughly 1/2 of all lower limb muscles, and prolonged delays between injury and recruitment onset were sometimes seen. Injury to the thoracolumbar spine was frequently associated with very long delays (i.e. >1 year) between injury and resumption of volitional contraction of distal lower limb muscles.

DISCUSSION

The incidence of neurologically incomplete SCI is rising. In such subjects, delays of 1 or more months between injury and the onset of voluntary contraction are common for muscles of the distal upper limbs (for cervical injury) and lower limbs. Given the abbreviated period of in-patient rehabilitation now routine in the United States, these subjects in particular will benefit from frequent follow-up evaluations to assess spontaneous recovery and design appropriate rehabilitation strategies to maximize functional independence. Moreover, the potential for delayed recovery must be considered when designing and implementing novel clinical interventions for treating SCI, to better differentiate between spontaneous and treatment-related improvements in neurologic function.

Spinal congenital dermal sinuses: a 30-year experience

OBJECTIVE

Dermal sinus tracts are an uncommon form of spinal dysraphism often presenting in childhood with skin findings, neurologic deficit, or infection. We reviewed our surgical experience, examining presenting symptomatology, operative findings, and patient outcomes.

METHODS

A retrospective analysis of operated dermal sinus tract cases by the senior author (A.H.M.) from 1970 to present was made.

RESULTS

Twenty-eight patients were identified; 17 female and 11 male. Five cervical, 4 thoracic, 9 lumbar, and 9 lumbosacral tracts were explored. Sixteen patients presented at <1 year of age, and 12 were >1 year. Reasons for referral included cutaneous findings (15), neurologic deficit (8), foot abnormalities (4), infection (3), pain (2), and scoliosis (1). Our initial examination revealed cutaneous findings (eg, sinus ostea, pigmentation changes, erythema, skin tags, subcutaneous masses) in 27 patients and neurologic deficit in 19. Age-related differences were apparent. Patients >1 year were more likely to have neurologic deficit (92%) as compared with those <1 year (50%). Bifid spinous processes were noted at dural tract entry in 17 patients. Twenty-two tethered cords, 14 inclusion tumors, and 6 patients with evidence of arachnoiditis were found intraoperatively. Mean follow-up was 33 months. Eleven (39%) remained neurologically intact, 12 (43%) improved, 2 (7%) were unchanged, and 3 (11%) were worse with 2 having decreased perianal sensation and 1 slightly worsened motor function postoperatively.

CONCLUSIONS

Although most patients were referred for cutaneous stigmata evaluation, >50% had neurologic deficit, intradural tumors, or tethered cords. Skin findings identification should initiate prompt radiologic evaluation and neurosurgical intervention with intradural exploration. Timely intervention may preserve or improve neurologic function in these patients.

Post-traumatic syringomyelia: a review

More than a quarter of spinal cord injured patients develop syringes and many of these patients suffer progressive neurological deficits as a result of cyst enlargement. The mechanism of initial cyst formation and progressive enlargement are unknown, although arachnoiditis and persisting cord compression with disturbance of cerebrospinal fluid flow appear to be important aetiological factors. Current treatment options include correction of bony deformity, decompression of the spinal cord, division of adhesions, and shunting. Long-term improvement occurs in fewer than half of patients treated. Imaging evidence of a reduction in syrinx size following treatment does not guarantee symptomatic resolution or even prevention of further neurological loss. A better understanding of the causal mechanisms of syringomyelia is required to develop more effective therapy.

The initial treatment of meningocele and myelomeningocele lesions in adulthood: experiences with seven patients

This is a retrospective study of patients having undergone surgical treatment of spina bifida cystica (SBC) lesions in adulthood. The objectives were to assess the clinical, radiological, and surgical characteristics of SBC lesions in adults. There is almost no study assessing these characteristics. Seven adult male patients with SBC lesions, ages between 20 and 23 (mean 21.1), had their primary evaluations between 1995 and 1999 in the Military Hospital, Yzmir, and Gülhane Military Medical Academy, Ankara. A temporary cerebrospinal fluid leak in the patient with the thoracic lesion and a temporary partial urinary incontinence in the patient with the lumbosacral lesion occurred. The most common preoperative complaint was low back pain. This improved in three of four patients (75%) but did not disappear. Although it is rare, an adult with an untreated SBC is a possible entity. These lesions should be included in the differential diagnosis of dorsal midline lesions in adults. Even though they appear as a simple spinal meningocele clinically, preoperative MR imaging and CT are necessary and helpful in the precise diagnosis and surgical planning.

Surgical treatment of post-traumatic myelopathy associated with syringomyelia

STUDY DESIGN

Retrospective review.

OBJECTIVE

Evaluate the clinical outcome of surgical intervention for post-traumatic syringomyelia.

INTRODUCTION

Progressive post-traumatic cystic myelopathy (PPCM), or syringomyelia, can occur after spinal cord injury. The authors present their surgical treatment protocol and treatment outcome of a series of patients with post-traumatic syringomyelia.

METHODS

The medical records of 53 patients with PPCM undergoing surgical treatment were reviewed. Laminectomies and intraoperative ultrasonography were performed. For patients with no focal tethering and only a confluent cyst on ultrasonography, a syringosubarachnoid shunt (stent) was inserted. For patients with both tethering and a confluent cord cyst, an untethering procedure was performed first. When a cyst showed significant size reduction (>50%) after untethering, no shunt was placed. When the cyst size persisted on ultrasonographic images, a short syringosubarachnoid shunt was used. The mean follow-up was 23.9 months for the 45 patients available for follow-up (range 12-102 months).

RESULTS

The interval between the causative event and the operation was from 5 months to 37 years (mean 6.5 years). Pain was the most frequent manifestation, followed by motor deterioration and spasticity. Postoperative improvements in >50% of the patients were noted in those presenting with worsening motor function or spasticity. In 19 of 28 patients with associated tethered spinal cord, untethering alone caused significant collapse of the cyst. Postoperative MRI demonstrated cyst collapse in 95% of the patients with untethering alone and 93% of the patients with a syringosubarachnoid shunt.

CONCLUSION

Post-traumatic syringomyelia can occur with or without cord tethering. Untethering alone for patients with cord tethering and cyst formation can reduce cyst size and alleviate the symptoms and signs of syringomyelia in the majority of these cases. Untethering with expansion of subarachnoid space with an expansile duraplasty may be a more physiologic way of treating a tethered cord with associated syringomyelia, i.e., treating the cause rather than the result.

Outcome after surgical treatment of progressive posttraumatic cystic myelopathy

OBJECT

Progressive posttraumatic cystic myelopathy (PPCM) can occur after an injury to the spinal cord. Traditional treatment of PPCM consists of inserting a shunt into the cyst. However, some authors have advocated a more pathophysiological approach to this problem. The authors of the present study describe their surgical treatment protocol and outcome in a series of patients with syringomyelia.

METHODS

Medical records of 34 patients undergoing surgical treatment for PPCM were reviewed. Laminectomies and intraoperative ultrasonography were performed. In patients without focal tethering of the spinal cord and in whom only a confluent cyst had been revealed on ultrasonography, a syringosubarachnoid shunt was inserted; in those with both tethering and a confluent cord cyst, an untethering procedure was performed first. When a significant reduction (>50%) in the size of the cyst was shown after the untethering procedure, no shunt was inserted. When no changes in cyst size were demonstrated on ultrasonography, a short syringosubarachnoid shunt was used. The mean follow-up period was 28.7 months (range 12-102 months). The interval between the mechanism of injury and the operation ranged from 5 months to 37 years (mean 11 years). Pain was the most frequent symptom, which was followed by motor deterioration and spasticity. Postoperative improvement was noted in 55% of patients who experienced motor function deterioration and in 53% of those who demonstrated worsening spasticity. In 14 of 18 patients with an associated tethered spinal cord, tethering alone caused significant collapse of the cyst. Postoperative magnetic resonance imaging demonstrated cyst collapse in 92% of patients who had undergone untethering alone and in 93% of those who underwent syringosubarachnoid shunt placement. Treatment failure was observed in 7% of the former group and in 13% of the latter.

CONCLUSIONS

Posttraumatic cystic myelopathy can occur with or without the presence of tethered cord syndrome. Intraoperative ultrasonography can readily demonstrate this distinction to aid in surgical decision making. Untethering alone in patients with tethered cord syndrome and cyst formation can reduce the cyst size and alleviate symptoms and signs of posttraumatic cystic myelopathy in the majority of these cases. Untethering procedures in which duraplasty is performed to expand the subarachnoid space may be a more physiologically effective way of treating tethered cord with associated syringomyelia.

Electrodiagnosis in spinal cord injured persons with new weakness or sensory loss: central and peripheral etiologies

OBJECTIVE

To assess the prevalence and causes of late neurologic decline of persons with spinal cord injury (SCI).

DESIGN

Retrospective review of persons with SCI over a 9-year period. Those with complaints of new weakness or sensory loss were grouped into three categories based on clinical examination, electrodiagnosis, and imaging: (1) central pathology (ie, brain, spinal cord, or nerve root); (2) peripheral pathology (plexus or peripheral nerve); or (3) no identifiable etiology. The specific diagnoses of late neurologic decline were identified.

SETTING

Regional Veterans Affairs Spinal Cord Injury Service.

PATIENTS

Five hundred two inpatient and outpatient adults with SCI.

RESULTS

Nineteen percent of the study population complained of new weakness and/or sensory loss. Neurologic abnormalities were noted in 13.5%, 7.2% with central and 6.4% with peripheral causes. The most common pathologies were posttraumatic syringomyelia (2.4%) and cervical (1.6%) and lumbosacral (1.2%) myelopathy/radiculopathy. A specific etiology was not determined in 6 cases (1.6%). Peripheral involvement was mostly from ulnar nerve entrapment (3.4%) and carpal tunnel syndrome (3.0%).

CONCLUSIONS

Late-onset neurologic decline is common after SCI and can result from central or peripheral pathology. Regular neurologic monitoring of SCI patients is recommended, since many with neurologic decline respond favorably if diagnosed and treated early.

A review of biomechanics of the central nervous system--Part III: spinal cord stresses from postural loads and their neurologic effects

OBJECTIVE

To review literature pertaining to neurologic disorders stemming from abnormal postures of the spine.

DATA COLLECTION

A hand search of available reference texts and a computer search of literature from Index Medicus sources was performed, with special emphasis placed on spinal cord stresses and strains caused by various postural rotations and translations of the skull, thorax, and pelvis.

RESULTS

Spinal postures will often deform the neural elements within the spinal canal. Spinal postures can be broken down into four types of loading: axial, pure bending, torsion, and transverse, which cause normal and shear stresses and strains in the neural tissues and blood vessels. Prolonged stresses and strains in the neural elements cause a multitude of disease processes.

CONCLUSION

Four types of postural loads create a variety of stresses and strains in the neural tissue, depending on the exact magnitude and direction of the forces. Transverse loading is the most complex load. The stresses and strains in the neural elements and vascular supply are directly related to the function of the sensory, motor, and autonomic nervous systems. The literature indicates that prolonged loading of the neural tissue may lead to a wide variety of degenerative disorders or symptoms. The most offensive postural loading of the central nervous system and related structures occurs in any procedure or position requiring spinal flexion. Thus flexion traction, rehabilitation positions, exercises, spinal manipulation, and surgical fusions in any position other than lordosis for the cervical and lumbar spines should be questioned.

Spinal cord hamartoma: case report

OBJECTIVE AND IMPORTANCE

Spinal cord hamartomas are infrequently mentioned in the literature. The authors present a unique report detailing the clinical presentation of a spinal cord hamartoma, with supporting radiographic and pathological data.

CLINICAL PRESENTATION

A 26-year-old man presented with progressive right upper extremity weakness. Imaging studies revealed an exophytic cervical spinal cord mass.

INTERVENTION

Open biopsy was undertaken and revealed tethering of the lesion to the dura. A pathological examination revealed a spinal cord hamartoma.

CONCLUSION

The patient's symptoms improved postoperatively, suggesting that tethering of the spinal cord was responsible for the symptoms. Although unusual, hamartoma should be included in the differential diagnosis of an exophytic spinal cord lesion.

A critical appraisal of syrinx cavity shunting procedures

OBJECT

This study was conducted to evaluate the results of shunting procedures for syringomyelia.

METHODS

In a follow-up analysis of 42 patients in whom shunts were placed in syringomyelic cavities, the authors have demonstrated that 21 (50%) developed recurrent cyst expansion indicative of shunt failure. Problems were encountered in patients with syringomyelia resulting from hindbrain herniation, spinal trauma, or inflammatory processes. A low-pressure cerebrospinal fluid state occurred in two of 18 patients; infection was also rare (one of 18 patients), but both are potentially devastating complications of shunt procedures. Shunt obstruction, the most common problem, was encountered in 18 patients; spinal cord tethering, seen in three cases, may account for situations in which the patient gradually deteriorated neurologically, despite a functioning shunt.

CONCLUSIONS

Placement of all types of shunts (subarachnoid, syringoperitoneal, and syringopleural) may be followed by significant morbidity requiring one or more additional surgical procedures.

Management of posttraumatic syringomyelia using an expansile duraplasty. A case report

STUDY DESIGN

A patient in whom posttraumatic syringomyelia developed 34 years after an L2 fracture is reported.

OBJECTIVES

To review the pathophysiology and current management modalities for posttraumatic syringomyelia. The delayed presentation and management rationale of this case are emphasized.

SUMMARY OF BACKGROUND DATA

This case represents the most delayed onset of symptoms from a posttraumatic syrinx reported in the literature. Although lysis of arachnoid adhesions and expansile duraplasty to recreate the subarachnoid space have been described for nonshuntable syrinxes, this form of management was used as the primary management modality in this case.

METHODS

A posttraumatic syrinx was managed by lysis of the arachnoid adhesions, fenestration of the cyst, and an expansile duraplasty.

RESULTS

After surgery, the patient's symptoms improved, and magnetic resonance imaging showed a decrease in the size of the syrinx.

CONCLUSION

Posttraumatic syringomyelia represents one of the few surgically remediable presentations of spinal cord injury. Consequently, it is necessary to continuously develop and monitor new management options for this disease. In the case reported here, the syrinx was treated successfully without the implanting a drainage tube.

Surgical resection of intramedullary spinal cord cavernous malformations: delayed complications, long-term outcomes, and association with cryptic venous malformations

OBJECTIVE

To examine outcomes and delayed complications after the surgical resection of intramedullary spinal cord (IMSC) cavernous malformations. The association of these lesions with cryptic intraparenchymal venous malformations at surgery also was analyzed.

METHODS

The records of 17 patients who underwent resection of their histologically verified IMSC cavernous malformations were analyzed. There were nine female and eight male patients (mean age, 40.1 yr). The locations of the cavernous malformations were as follows: cervical, eight; thoracic, eight; and conus medullaris, one. The mean follow-up period was 48.3 months. Immediate postoperative and long-term neurological outcomes were compared, and delayed complications were assessed.

RESULTS

The patients presented with radiculopathy (n = 6), myelopathy (n = 10), and conus medullaris syndrome (n = 1). Intraoperatively, 16 (94.1%) IMSC cavernous malformations were associated with cryptic venous malformations. Immediately after surgery, four (23.5%) patients worsened neurologically whereas one (5.9%) improved. At long-term follow-up, however, 10 (58.9%) patients had improved and only 1 (5.9%) remained worse. Four (23.5%) patients experienced delayed complications. Three had undergone incomplete resection and experienced subsequent hemorrhage, necessitating subsequent resection. Another patient developed radiological tethering of the thoracic spinal cord without clinical symptoms. Two of the three patients who had undergone subsequent resection developed symptomatic tethering of the cervical spinal cord. In one of the two patients, the tethering was associated with an iatrogenic cerebellar tonsillar herniation. Both patients required surgical intervention.

CONCLUSIONS

The frequent coexistence of IMSC cavernous malformations with cryptic venous malformations in this series indicates a need for operative vigilance to preserve these venous anomalies. Delayed complications were the result of incomplete resection. The resultant hemorrhage required reexploration, which led to tethering of the spinal cord. Most patients who underwent resection, however, had improved neurologically at long-term follow-up.

Progressive posttraumatic myelomalacic myelopathy: treatment with untethering and expansive duraplasty

Patients with progressive posttraumatic myelomalacic myelopathy (PPMM), or tethered cord syndrome, present with symptoms and signs similar to those observed in case of progressive posttraumatic cystic myelopathy, that is, sensorimotor function deterioration, local and/or radicular pain, increased spasticity, increased autonomic dysreflexia, and sphincter dysfunction. The authors investigated surgical outcomes of untethering combined with expansive duraplasty. Forty patients with PPMM who presented with functional deterioration underwent untethering of the spinal cord and nerve roots with an expansive duraplasty. Meticulous dissections of adhesions on the dorsal and lateral aspects of the spinal cord and nerve roots were performed. Intraoperative ultrasonography was used to detect the presence of a confluent cyst and to assess the success of untethering. After surgery, the patients were treated using a protocol that involved frequent turning for 48 hours and subsequently mobilization. Preoperative magnetic resonance (MR) imaging, with and without administration of a contrast agent, was obtained in all patients, except one patient who underwent immediate and delayed computerized tomography (CT) myelography. The mean follow-up period was 3 years (range 20-57 months) for the 36 patients available for follow-up review. Spinal cord tethering was observed in all patients preoperatively. Trauma was the most common cause of this pathology, accounting for 31 of the 40 cases. Preoperative MR imaging did not demonstrate tumor recurrence in the group of five patients who had undergone an initial operation for tumor excision. The interval between the causative event and the operation was less than 5 years in half of the patients (20 of 40), with the longest interval lasting up to 37 years. Motor function deterioration was the most frequent manifestation; it was present in 31 of 40 patients. Improvements in motor function, autonomic dysreflexia, pain, sphincter dysfunction, and sensory function were found during the most recent follow-up examination in 79%, 75%, 62%, 50%, and 43% of the patients, respectively. Two patients experienced retethering of the spinal cord and one underwent a second operation. Surgical untethering and expansive duraplasty, followed by postoperative position rotation to avoid retethering, provide symptomatic relief for patients with PPMM.

Spinal cord injury rehabilitation. 2. Medical complications

This self-directed learning module highlights new advances in understanding medical complications of spinal cord injury through the lifespan. It is part of the chapter on spinal cord injury rehabilitation in the Self-Directed Physiatric Education Program for practitioners and trainees in physical medicine and rehabilitation. This article covers reasons for transferring patients to specialized spinal cord injury centers once they have been stabilized, and the management of common medical problems, including fever, autonomic dysreflexia, urinary tract infection, acute and chronic abdominal complications, deep vein thrombosis, pulmonary complications, and heterotopic ossification. Formulation of an educational program for prevention of late complications is also discussed, including late renal complications, syringomyelia, myelomalacia, burns, pathologic fractures, pressure ulcers, and cardiovascular disease. New advances covered in this section include new information on old problems, and a discussion of exercise tolerance in persons with tetraplegia, the pathophysiology of late neurologic deterioration after spinal cord injury, and a view of the care of these patients across the lifespan.

Brainstem tethering in Dandy-Walker syndrome: a complication of cystoperitoneal shunting. Case report

Treatment of the Dandy-Walker syndrome has included placement of a ventriculoperitoneal shunt alone or in combination with a posterior fossa cystoperitoneal shunt. Complications in shunting are common and are usually related to malfunction or infection. The authors present a case in which the patient developed headaches and focal cranial nerve deficits following infection caused by a cystoperitoneal shunt. Magnetic resonance imaging showed tethering of the brainstem. A posterior fossa craniotomy with microsurgical untethering and cyst fenestration achieved two goals: improvement of the focal cranial nerve deficits and elimination of the cystoperitoneal shunt.

Posterior fossa decompression for Chiari I deformity, including resection of the cerebellar tonsils

This is an analysis of 19 consecutive cases of symptomatic patients with Chiari I deformities, undertaken to evaluate the long-term effect of posterior fossa decompression and duraplasty, assessed by postoperative imaging. Sixteen of the patients had syringomyelia and three had foramen magnum syndromes without a syrinx. Eighteen patients underwent posterior fossa craniectomy, subpial resection of the cerebellar tonsils, and duraplasty. Four patients were 16 years of age or younger. One of the children with syringomyelia had a posterior fossa decompression without resection of the tonsils. In the 15 patients with syringomyelia whose surgery included resection of the tonsils, the syrinx was reduced or resolved in 14. The patient whose syrinx did not change was a child with a lumbosacral lipoma. Three patients had syndromes of the foramen magnum without a syrinx, and of these only a patient with prior chemical and bacterial meningitis caused by a lumboureteral shunt failed to improve dramatically. When our patients are combined with 40 in the literature treated by decompression and duraplasty, 51 of 55 patients had reduction or resolution of the syrinx. Although it does not clearly affect the result, resection of the tonsils can be done safely.

Spontaneous regeneration of the foramen magnum after decompressive suboccipital craniectomy in Chiari malformation: case report

A 21-year-old woman, who had undergone foramen magnum decompression for her symptomatic Chiari malformation (Type 1) 7 years before, presented with recurrence of the symptoms. Neuroradiological examinations demonstrated regeneration of the foramen magnum that was caused by new bone formation, as confirmed at the second surgery. Neurological improvement was obtained after the removal of the regenerated foramen magnum. This observation, though rare, deserves to be kept in mind during the postoperative follow-up period in young patients with Chiari malformation.