Table of Contents
Lumbar spinal schwannoma
Neurosurgery Department, General University Hospital Alicante, Spain
Spinal schwannoma in the lumbar region.
Epidemiology
The two most common intradural extramedullary lesions of the lumbar spine are meningioma and schwannoma.
Completely extradural schwannomas of the lumbar spine are extremely rare lesions.
Classification
Clinical features
The first symptoms included low back pain and radicular pain. It was reported that the pain increases at night and in the late period of the tumor, spinal cord findings occur as well.
The lumbosacral root schwannoma is a rare cause of sciatica and may raise confusion in diagnosis with late discovery of the tumor. Nerve root schwannomas should be considered in the differential diagnosis of sciatica, especially when signs and symptoms of sciatica cannot be simply explained by prolapsed disc syndrome, which can often delay the diagnosis 1).
Other signs of spinal schwannoma included motor weakness, sphincter problems, and sensorial disorders.
Schwannomas rarely cause sciatica; hence, it is seldom considered in evaluation of a patient with radiculopathy.
The presentation of a tumor due to torsion, with hemorrhage from presumed reperfusion injury as a result of infarction of the lesion, is extremenly rare, and may be different than typical tumor presentation.
Patients with acute onset of severe radiating pain may have torsion of a benign tumor arising from the nerve in question 2).
Diagnosis
Differential diagnosis
Treatment
Accurate localization with cod liver oil capsules is quick, safe, cost-effective, and noninvasive with no exposure to radiation. It also reduces operating time by eliminating the need for intraoperative fluoroscopy 3).
see Spinal tumor surgery.
Case reports
A case of a 68-year-old woman who presented with progressive back pain and weakness in both lower limbs over the past months. The pain was initially localized to the lower back but gradually intensified and radiated down to the legs. The patient reported difficulty walking and a sensation of tingling and numbness in the feet. She denied any recent trauma or significant medical history. On physical examination, there was reduced muscle strength (3/5) in both lower limbs. The patient exhibited hyporeflexia in the knees and ankle. A magnetic resonance imaging (MRI) of the spine was performed, revealing a well-defined mass lesion located in the lumbar region, compressing the spinal cord from L2 to L5. The patient was counseled and prepared for surgical resection of the tumor. Histopathological findings revealed features of peripheral nerve sheath tumors and cellular schwannomas. The patient recovered well postoperatively. The surgeon operating should be mindful of the potential presence of a mobile schwannoma, even though it is rarely mentioned in the literature. Being aware of this possibility can help prevent unnecessary surgical dissection, which can lead to higher rates of complications and morbidity. Although it is plausible that this case could have involved a mobile schwannoma, there was not enough evidence to support it as we performed a laminectomy on multiple levels due to the tumor's size 4).
Case report from the HGUA
Q11711
A 34-year-old male several-month history of lumbosciatica neuropathic pain radiating towards the left leg, progressively incapacitating him and causing difficulty in walking despite positional changes. Additionally, he experienced occasional episodes of urinary incontinence.
Motor and sensory functions were preserved, except for partial loss of strength in dorsiflexion of the left foot.
Magnetic resonance imaging (MRI) revealed a focal hourglass-shaped lesion at the L4-L5 level, extending into the left L5-S1 neural foramen. Protruded discs were observed at L4-L5 and L5-S1. Investigations: The lesion, hypointense in T1 and enhancing with gadolinium, was consistent with a neurogenic origin. It predominantly affected the left L5 root, causing some central canal stenosis at L4-L5.
The findings were compatible with an intrathecal schwannoma extending from L4-L5 to the left L5-S1 neural foramen and extraforaminal region. Protruded discs were noted at L4-L5 and L5-S1.
Laminoplasty at L4-L5 Excision of the left L5 root neurinoma Intraoperative monitoring with motor-evoked potentials (MEP) and somatosensory-evoked potentials (SSEP).
Prone Position. Midline Lumbar skin incision and Bilateral Laminectomy of L4 and L5 with Piezoelectric Motor. Dural Opening from L4 to S1, Identifying a Large, Indurated Tumor in the Cauda Equina. Cranial root localization and motor function exclusion. Coagulation and cutting are performed. Careful separation of the remaining cauda equina roots to the left L5 foramen. Subsequently, through an extraforaminal approach, the L5 root's dura mater is opened, and the lesion is located between the nerves of the L5 root. The tumor is dissected and removed up to healthy tissue. Monitoring is maintained, preserving the intact motor function of the left L5. A hermetic dural closure of the root is performed, including medial durotomy. Laminoplasty with four titanium plates. Muscular and fascial closure is performed hermetically. Skin closure is done layer by layer with staples. A sample is sent to the pathology department for analysis.
The patient had a favorable postoperative course with a dry wound and clinical improvement.