====== Posttraumatic syringomyelia ====== ===== General information ===== Posttraumatic [[syringomyelia]] (PTSx) may follow significant [[spinal trauma]] (with or without clinical [[spinal cord injury]]). Includes [[penetrating injury]] or non-penetrating “violent” [[trauma]] to the [[spinal cord]] (injuries such as post-spinal anesthesia or following [[thoracic disc herniation]] are not included). ===== Epidemiology ===== Often a late presentation following [[spinal cord injury]], and therefore incidence is higher in series with longer follow-up. [[Incidence]] is increasing as a result of longer survival following spinal cord injury and improved detection with the proliferation of MRI scans. Range: ≈ 0.3–3% of cord injured patients In a large number of patients followed via multicenter cooperative data bank, there were fewer cases of syrinx following [[cervical spine injury]] than following thoracic injuries ((Vernon JD, Chir B, Silver JR, et al. Posttraumatic Syringomyelia. Paraplegia. 1982; 20:339–364)) (may be artifactual since patients with lower lesions may be more aware of ascending levels). Latency following spinal cord injury: 1. latency to symptoms: 3 mos to 34 yrs (mean 9 yrs) (earlier in complete cord lesions than incomplete: mean 7.5 vs. 9.9 yrs. 2. latency to diagnosis: up to 12 yrs (mean 2.8 yrs) after the onset of new symptoms ===== Clinical ===== The late appearance of upper extremity symptoms in a paraplegic patient should raise a high index of suspicion of posttraumatic syringomyelia ((Griffiths ER, McCormick CC. Posttraumatic Syringomyelia (Cystic Myelopathy). Paraplegia. 1981; 19:81–88)) [[Hyperhidrosis]] may be the only feature of descending syringomyelia in patients with complete cord lesions ((Stanworth PA. The Significance of Hyperhidrosis in Patients with Posttraumatic Syringomyelia. Paraplegia. 1982; 20:282–287)) ===== Evaluation ===== One end of the cavity is often found at a site of [[spinal fracture]] or abnormal angulation. ===== Management ===== ==== General information ==== Many authors advocate early surgical drainage of cysts as a means of reducing the increased delayed deficit ((Dworkin GE, Staas WE. Posttraumatic Syringomyelia. Arch Phys Med Rehabil. 1985; 66: 329–331)). Some authors feel that aside from disturbing sensory symptoms, the motor loss was infrequent and therefore conservative management is indicated in most cases ((Watson N. Ascending Cystic Degeneration of the Cord After Spinal Cord Injury. Paraplegia. 1981; 19: 89–95)). ==== Medical ==== Managed non-surgically: 31% remained stable, 68% progressed over yrs (longer F/U in latter). ==== Surgical ==== There is probably no benefit in operating on a patient with a small syrinx ((Rossier AB, Foo D, Shillito J, et al. Posttraumatic Cervical Syringomyelia. Brain. 1985; 108:439–461)) === Surgical options === Same as in communicating syringomyelia, with the following differences: 1. cord transection (cordectomy) ((Durward QJ, Rice GP, Ball MJ, et al. Selective Spinal Cordectomy: Clinicopathological Correlation. J Neurosurg. 1982; 56:359–367)) : an option in complete injuries only 2. plugging the obex is probably not indicated (controversial in congenital syrinx). ===== Outcome ===== In 9 PTSx patients treated with syringosubarachnoid shunt ((Rossier AB, Foo D, Shillito J, et al. Posttraumatic Cervical Syringomyelia. Brain. 1985; 108:439–461)): pain relieved in all 9 (1 only slightly), motor recovery in 5/8, improved tendon reflex in 1/10. Some post-op complications in 9 patients included: 1 incomplete lesion became complete, 1 sensorimotor deterioration, transient pain in 3. Most results are good for radicular symptoms, with dubious efficacy for autonomic symptoms or spasticity. ---- Syrinx shunting, and in particular [[syringosubarachnoid shunt]]ing (SSAS), provides neurological improvement or stabilization in at least 50% of these patients. Given the debilitated condition of many of these patients, a minimally invasive approach to the insertion of these devices is desirable. ===== Case reports ===== ==== 2019 ==== A patient with a complex L3 burst fracture from a remote trauma s/p stabilization. Thirty-two years later, he developed progressive neck pain, upper extremity radiculopathy, dysesthesias, and clinical myelopathy (dropping objects, gait imbalance). An MRI demonstrated an expansile syrinx from C2-conus medullaris which previously had been unsuccessfully treated by fenestration. We offered a T1-2 laminectomy and placement of synringosubarachnoid shunt. In the associated video (Supplemental Digital Content 1, http://links.lww.com/CLINSPINE/A107), we demonstrate the step-by-step approach for this procedure, including microsurgical intradural intramedullary exploration and insertion of a T-tube shunt catheter. We additionally demonstrate nuances of ultrasonography that guide medullary entry localization and confirmation of successful shunt placement. Finally, we review preoperative planning pearls pertinent to revision surgeries, pitfalls of the operation, and postoperative management strategies germane to successful outcomes ((Hussain I, Greenfield JP. Ultrasound-guided Syringosubarachnoid Shunt Insertion for Cervicothoracic Syringomyelia. Clin Spine Surg. 2019 Jun 18. doi: 10.1097/BSD.0000000000000835. [Epub ahead of print] PubMed PMID: 31220040. )). ===2017=== A 40-year-old man with complete paraplegia since 1991 as consequence of a Th4 vertebral fracture showed a great posttraumatic syringomyelia that extended up to C2 vertebral level, without signs of recent worsening. 150 x 106 autologous MSCs were injected into the syrinx, without drainage or aspiration. One year after cell therapy, syrinx was reduced without collapse of cervical spinal cord. In the course of follow-up, clear clinical improvement was observed, mainly in sphincter dysfunction. Injection of MSCs in the syrinx of posttraumatic syringomyelia is safe and is associated with clinical and neuroimaging improvement. The possibility of cell therapy as a new approach to posttraumatic syringomyelia, or even for idiopathic syringomyelia, is an open door that requires further studies ((Vaquero J, Hassan R, Fernández C, Rodríguez-Boto G, Zurita M. Cell Therapy as a New Approach to the Treatment of Posttraumatic Syringomyelia. World Neurosurg. 2017 Aug 10. pii: S1878-8750(17)31316-5. doi: 10.1016/j.wneu.2017.08.019. [Epub ahead of print] PubMed PMID: 28804041. )) ===2007=== O'Toole et al. provide the first report of an SSAS inserted in a minimally invasive fashion through a tubular retractor ((O'Toole JE, Eichholz KM, Fessler RG. Minimally invasive insertion of syringosubarachnoid shunt for posttraumatic syringomyelia: technical case report. Neurosurgery. 2007 Nov;61(5 Suppl 2):E331-2; discussion E332. doi: 10.1227/01.neu.0000303990.03235.81. PubMed PMID: 18091225. )). ===== References =====