What is the treatment for diastematomyelia?

Treatment of Diastematomyelia

Surgical excision of the bony or fibrous septum is the definitive treatment for Type I diastematomyelia with progressive neurological deterioration or tethered cord, while conservative management is recommended for asymptomatic Type I cases and all Type II diastematomyelia. 1

Classification and Clinical Significance

Diastematomyelia is classified into two distinct types that require different management approaches:

• Type I diastematomyelia (more common, ~75% of cases) features double dural tubes with a rigid bony or cartilaginous septum dividing the spinal cord 1, 2
• Type II diastematomyelia features a single dural tube with a fibrous septum 1, 2
• Type I cases present with significantly higher incidence of neurological deficits, characteristic dorsal skin changes, and congenital spinal or foot deformities compared to Type II 2

Diagnostic Evaluation

MRI of the complete spine is essential for diagnosis and surgical planning in all suspected cases of diastematomyelia. 3

Key diagnostic findings include:

• Characteristic kyphoscoliosis and widening of interpedicle distance on radiographs 2
• Visualization of the septum type (bony, cartilaginous, or fibrous) on CT or MRI 3
• Associated intraspinal anomalies occur in 21-43% of congenital scoliosis cases, with diastematomyelia being the most common 3
• A negative neurological examination does not predict a normal MRI and should not preclude imaging 3

Surgical Indications and Approach

Surgery is indicated for:

• Type I diastematomyelia with progressive neurological deterioration 1, 4
• Presence of tethered filum terminale 1
• Before corrective spinal surgery to prevent traction injury 5
• Symptomatic cases with worsening motor or sensory deficits 1, 2

Surgical technique involves:

• Laminectomy with excision of the bony or fibrous septum 1, 5
• Intradural exploration of the lumbar region to release tethering of the conus when present 1
• Careful attention to prevent cerebrospinal fluid leakage and epidural hematoma 1

Surgical Outcomes

In a large series of 156 patients with mean 4.5-year follow-up:

• Type I diastematomyelia: 78% (96/123) of surgical patients showed clinical improvement, with no worsening during follow-up 1
• Non-surgical Type I patients showed stabilization without progression 1
• Type II diastematomyelia: Surgical patients remained neurologically stable without significant functional improvement 1
• Complications included CSF leakage (2 patients), temporary neurological deterioration (4 patients), and epidural hematoma (1 patient) 1

Conservative Management

Conservative treatment is recommended for:

• Asymptomatic Type I diastematomyelia without progressive deficits 1
• All Type II diastematomyelia cases 1
• Stable, non-progressing neurological deficits 5

Conservative measures include:

• Observation with serial neurological examinations 5
• Balanced lifestyle modifications and avoidance of heavy physical work 4
• Caution with aggressive physiotherapy, which may intensify pain and neurological complaints 4

Critical Pitfalls to Avoid

• Never proceed with elective scoliosis surgery without complete spinal imaging to identify diastematomyelia and prevent traction injury to the tethered cord 4, 5
• Rehabilitation and physiotherapy can worsen symptoms and should be stopped if pain intensifies 4
• Surgical intervention for Type II diastematomyelia rarely produces functional improvement and should be avoided 1
• Timing of surgery is critical—operate before significant irreversible neurological damage occurs 1, 2