Surgical management of adult type 1 split cord malformation. Report of two cases with literature review

Classification of and individual treatment strategies for complex tethered cord syndrome

Objective

To study the classification, diagnosis, and treatment strategies of complex tethered cord syndrome (C-TCS) on the basis of the patients' clinical symptoms, imaging findings, and therapeutic schedule.

Methods

The clinical data of 126 patients with C-TCS admitted to our department from January 2015 to December 2020 were retrospectively analyzed. Classification criteria for C-TCS were established by analyzing the causes of C-TCS. Different surgical strategies were adopted for different types of C-TCS. The Kirollos grading, visual analogue scale (VAS), critical muscle strength, and Japanese Orthopaedic Association (JOA) scores were used to evaluate the surgical outcomes and explore individualized diagnosis and treatment strategies for C-TCS.

Results

C-TCS was usually attributable to three or more types of tether-causing factors. The disease mechanisms could be categorized as pathological thickening and lipomatosis of the filum terminal (filum terminal type), arachnoid adhesion (arachnoid type), spina bifida with lipomyelomeningocele/meningocele (cele type), spinal lipoma (lipoma type), spinal deformity (bone type), and diastomyelia malformation (diastomyelia type). Patients with different subtypes showed complex and varied symptoms and required individualized treatment strategies.

Conclusion

Since C-TCS is attributable to different tether-related factors, C-TCS classification can guide individualized surgical treatment strategies to ensure complete release of the tethered cord and reduce surgical complications.

Thoracolumbar surgery for degenerative spine diseases complicated with tethered cord syndrome: A case report

BACKGROUND

Tethered cord syndrome (TCS) secondary to split cord malformation (SCM) is rare in adulthood. There is as yet no consensus about the optimal treatment method for adult patients with SCMs and degenerative spine diseases such as lumbar stenosis, spondylolisthesis and ossification of the ligamentum flavum (OLF). The tethered cord poses a great challenge to the decompression and fusion procedures for the intraoperative stretching of the spinal cord, which might lead to deteriorated neural deficits. Here, we report on a case to add our treatment experience to the medical literature.

CASE SUMMARY

We treated a 67-year-old female patient with type II SCM suffering from lumbar disc herniation, degenerative lumbar spondylolisthesis and thoracic OLF. The patient underwent thoracolumbar spinal fusion and decompression surgery for severe lower back pain, extensive left lower limb muscle weakness and intermittent claudication. After the thoracolumbar surgery, without stretching the tethered cord, the patient achieved complete relief of pain and lower extremity weakness at final follow-up.

CONCLUSION

For adult patients with underlying TCS secondary to SCM coupled with thoracic OLF and lumbar spondylolisthesis, a thoracolumbar fusion surgery could be safe and effective with the tethered cord untreated. It is critical to design individualized surgical protocols to reduce the stretch of the low-lying spinal cord.

Adult-onset presentation of cervicothoracic split cord malformation: illustrative case

BACKGROUND

A 60-year-old female presented with a 6-month history of progressive lower limb pain, weakness, and declining mobility. She was initially diagnosed as having possible hip osteoarthritis or ligamental knee injury. She was eventually seen by a neurologist, who admitted her to a tertiary hospital with new-onset upper motor neuron signs and urinary incontinence. Magnetic resonance imaging of the whole spine revealed evidence of C7–T2 type 1 split cord malformation (SCM) necessitating urgent spinal surgery. She had an excellent outcome with intensive rehabilitation and returned to her premorbid level of function and mobility.

OBSERVATIONS

The patient presented with nonspecific symptoms, which led to multiple referrals and a significant delay in her diagnosis.

LESSONS

Clinicians should be aware of the importance of a detailed history with thorough neurological and spinal examinations.

A Type II Split Cord Malformation in an Adult Patient: An Operative Case Report

BACKGROUND AND IMPORTANCE

Split cord malformations (SCMs) are rare conditions in which the spinal cord is split into two hemicords within either a single thecal sac or two separate thecal sacs. The hemicords are typically split by a bony or fibrous structure. We present an adult patient who presented with a type II SCM with tethered cord. This is the first case of such a presentation with an accompanying intraoperative video. Unusual features of the case were the presence of an incomplete fibrous septum and lack of a discrete filum terminale.

CLINICAL PRESENTATION

A 50-yr-old woman presented with back pain, radiculopathy, urinary urgency, and episodic fecal incontinence. Her exam was notable for weakness of the right extensor hallicus longus. Imaging showed an SCM extending from L3 to S1, a fibrous septum located at L4-5, and a low-lying conus at S4. She was treated with a decompressive L3-S4 laminectomy and disconnection of all the dural attachment points. She required lumbar drain placement postoperatively and reoperation for wound dehiscence and persistent pseudomeningocele. At the time of last follow-up, she was neurologically intact with improvement in bowel/bladder function.

CONCLUSION

SCM is an uncommon presentation in adults and is often accompanied by findings of skin stigmata, tethered cord, and other central nervous system/skeletal anomalies. Obtaining full multimodal imaging is critical to understanding subtle anatomic variations that can pose operative challenges. We report the treatment of an adult patient with type II SCM, and provide an intraoperative video demonstrating the removal of an incomplete midline fibrous septum.

Klippel-Feil Syndrome with Cervical Diastematomyelia in an Adult with Extensive Cervicothoracic Fusions: Case Report and Review of the Literature

Split cord malformation (SCM) is a developmental disorder that is usually symptomatic and diagnosed in childhood. The majority of these lesions are in the thoracic and lumbar spine, with only 1%-3% of cases found in the cervical spine. This is a case report of a 55-year-old female patient with an unremarkable medical history who presented with neck pain. Upon workup, she was found to have extensive developmental anomalies throughout her cervical and thoracic spine, including an incidentally found type 2 SCM and multiple autofused vertebrae. There are only 6 similar studies published in the literature. There was extensive facet degeneration in her cervical spine, which was suspected to be the etiology of her neck pain. This case illustrates the rare finding of asymptomatic adult cervical SCM and the likely significance of her autofused vertebrae causing accelerated symptomatic facet spondylosis.

Split cord malformation in adults: Literature review and classification

The objective of this study was to summarize the available literature describing the presentation, diagnostic evaluation, and management for adults with Type 1 and Type 2 split spinal cord malformations. A review of the literature was performed using the CINAHL, PubMed, Embase, and Web of Science database, alongside all associated bibliographies, to include studies describing Type 1 and Type 2 split cord malformations diagnosed in patients above the age of 18. All relevant studies of split cord malformations were included, regardless of the year published and terminology used to describe the dysraphism. Clinical case series (≥ 2 patients), cohort studies, and review articles comprising adult patients with radiographically diagnosed diastematomyelia, diplomyelia, or dimyelia were included (Class of Evidence I-IV). A total of 17 unique articles, describing 146 unique adult spinal cord malformation subjects, were included. The most common associated condition was tethered cord syndrome (59.8 %). Operative management for symptomatic split cord malformation was performed in 72.3 % of cases. For those with preoperative neurologic deficits, operative management resulted in symptomatic improvement in 96.6 %, compared to 0 % conservative management (p < 0.05). For those with pain alone, operative management resulted in improvement of 91.1 %, compared to 12.5 % conservative management (p < 0.05). To date, this is the only literature review to include all split cord malformations (SCM Types I and II) presenting in adulthood, with clinical characteristics, associated conditions, and long-term treatment outcomes.

Type I split cord malformation and tethered cord syndrome in an adult patient: A case report and literature review

Background:

In a split cord malformation (SCM), the spinal cord is divided longitudinally into two distinct hemicords that later rejoin. This can result in a tethered cord syndrome (TCS). Rarely, TCS secondary to SCM presents in adulthood. Here, we present an adult female with Type I SCM resulting in TCS and a review of literature.

Case Description:

A 57-year-old female with a history of spina bifida occulta presented with a 2-year history of worsening back and left leg pain, difficulty with ambulation, and intermittent urinary incontinence; she had not responded to conservative therapy. Magnetic resonance imaging (MRI) revealed a tethered cord secondary to lumbar type I SCM. The patient underwent an L1–S1 laminectomy for resection of the bony septum with cord detethering. At 2-month follow-up, the patient had improvement in her motor symptoms and less pain. In literature, 25 cases of adult-onset surgically managed SCM with TCS were identified (between 1936 and 2018). Patients averaged 37 years of age at the time of diagnosis, and 56% were female.

Conclusion:

TCS can present secondary to SCM in adulthood and is characterized predominantly by back and leg pain.

Split cord malformation associated with scoliosis in adults

Split cord malformations (SCMs) are rare congenital abnormalities arising from a primary neurulation defect during embryological development of the spinal cord. SCMs can lead to progressively worsening scoliosis and gait difficulties if left untreated. We report on two patients who atypically presented with SCM in adulthood and review previous reports.