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

Table 1 The intraoperative somatosensory evoked potentials and motor evoked potentials

	SEP (left)			SEP (right)			MEP (left)			MEP (right)
	P40 in ms	N50 in ms	Amplitude in μV	P40 in ms	N50 in ms	Amplitude in μV	P40 in ms	N50 in ms	Amplitude in μV	P40 in ms	N50 in ms	Amplitude in μV
Baseline	41.0	50.3	1.3	40.0	46.5	1.0	50.2	47.7	85.8	45.0	52.2	61.3
After lamina exposure	41.5	49.8	1.3	39.5	47.7	1.0	51.5	49.0	83.7	44.0	47.0	41.9
After thoracic decompression	42.5	51.2	0.7	40.5	46.5	0.8	48.3	46.0	186.6	52.5	50.5	284.2
After lumbar decompression	38.8	49.5	0.6	38.5	46.5	0.7	48.0	44.0	149.4	50.0	46.0	336.1

The electrical stimulation value was 400 mV. MEPs: Motor evoked potentials; SEPs: Somatosensory evoked potentials.

Table 2 Literature review of split spinal malformation/tethered cord syndrome in spinal surgery

Ref.	Country	Study type	Number of patients	Gender/age in yr	SCM type	Symptoms	Main diagnosis	Operation	Principles	Problems
Oh et al[13], 2021	United States	Case report	1	Female/50	Type II	Back and radiating leg pain; leg numbness; bowel/bladder incontinence	Spondylolisthesis	L5/S1 ALIF with posterior fixation	First to perform untethering procedure before spinal fusion surgery	High-volume drain output; pseudomeningocele; surgical exploration with wound debridement and repair
Kobets et al[5], 2021	United States	Case Series	6	4 Females/35-62	Type II	Radiating leg pain; lower extremity paresthesia; bladder and bowel dysfunction	/	/	Filamentectomy	Symptom recurrence
Chang et al[24], 2020	United States	Case report	1	Male/40	NM	leg pain; sensory changes; hyperreflexia, and gait disturbance	Lumbar disc herniation	Full endoscopic lumbar diskectomy	Treating the responsible lesions in a minimally invasive method without spinal cord detethering surgery	NM
Kaminker et al[9], 2000	United Kingdom	Case report	1	Male/38	Type I	Bilateral leg pain and neurogenic claudication	Lumbar spinal stenosis	Posterior decompression	Decompression with subtotal resection of the bony bar	Cerebrospinal fluid leak
Breton et al[15], 2020	United States	Case report	1	Female/79	NM	Leg pain; progressive gait deterioration and bilateral leg weakness	Lumbar spinal stenosis; spondylolisthesis	Sublaminoplasty for spinal cord decompression with onlay arthrodesis	Conduct a minimally invasive surgery with tethered cord untreated	NM
Hui et al[26], 2014	China	Case report	1	Male/23	Type I	Unstable walking and progressed numbness in the lower limbs	Kyphoscoliosis	Posterior segmental pedicle screw instrumented fusion with vertebral column resection	Vertebral column resection above bony spur to shorten the spine and decrease the stretched power on the spinal cord.	No complications
Endo et al[17], 2014	Japan	Case report	1	Male/43	NM	Progressive spastic gait disturbance; numbness; muscle weakness and pyramidal tract signs in the lower limbs	Lumbar disc herniation	Herniotomy via a posterolateral approach and instrumented posterolateral fusion	Decompression and posterolateral fusion without intervertebral fusion	No complications
Srinivas et al[23], 2012	United Kingdom	Case report	1	Female/77	NM	Severe low back pain and progressive paraparesis	Lumbar disc herniation	Posterior decompression	Indirectly decompression by the falling back spinal cord	Deep wound infection
König et al[25], 2012	United Kingdom	Case report	1	Female/26	Type II	Severe low back pain, and bilateral L5/S1 sciatica	Spondylolisthesis	Anterior in situ fusion coupled with pedicle screw fixation	Anterior fusion to minimize manipulation of neural structures	No complications
Kawamura et al[27], 2010	Japan	Case report	2	Male/69; Male/36	NM	1 Legs and low back pain with intermittent claudication; 2 Numbness and severe muscle weakness in the lower limbs	Lumbar spinal stenosis	Pedicle subtraction osteotomy and yellow ligament resection	Pedicle subtraction osteotomy to shorten the spine	NM
Kramer[28], 2009	Canada	Case report	1	Female/54	NM	Progressive pain and sensorimotor symptoms in the lower back and limbs	Thoracic disc herniation	Posterolateral partial vertebral body resection and decompression	Osteotomy to shorten the spine	NM

ALIF: Anterior lumbar intervertebral fusion; NM: Not mentioned; SCM: Split spinal malformation; TCS: Tethered cord syndrome.