Clinical evaluation of an innovative operative procedure in the treatment of the tethered cord syndrome

Accepted Manuscript Title: Clinical evaluation of an innovative operative procedure in treatment of the tethered cord syndrome. Author: Yang Hou, Jiangang Shi, Yongfei Guo, Jingchuan Sun, Yuan Wang, Guodong Shi, Guohua Xu PII: DOI: Reference:

S1529-9430(17)31060-4 https://doi.org/doi:10.1016/j.spinee.2017.10.009 SPINEE 57517

To appear in:

The Spine Journal

Received date: Revised date: Accepted date:

22-5-2017 25-9-2017 5-10-2017

Please cite this article as: Yang Hou, Jiangang Shi, Yongfei Guo, Jingchuan Sun, Yuan Wang, Guodong Shi, Guohua Xu, Clinical evaluation of an innovative operative procedure in treatment of the tethered cord syndrome., The Spine Journal (2017), https://doi.org/doi:10.1016/j.spinee.2017.10.009. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

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Title: Clinical evaluation of an innovative operative procedure in treatment of the

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tethered cord syndrome . Authors: Yang Hou, MD, Ph.D*, Jiangang Shi, MD, Ph.D*, Yongfei Guo MD, Ph.D*, Jingchuan Sun, MD, Ph.D*, Yuan Wang, MD, Ph.D*, Guodong Shi, MD, Ph.D*, Guohua Xu, MD, Ph.D*.

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BACKGROUND CONTEXT: The Tethered cord syndrome (TCS)

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characterized by urination dysfunction has long been a worldwide clinical

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problem, of which clinical effects remains controversial.

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PURPOSE: To evaluate clinical effects of an innovative surgical method

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for treatment of TCS.

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STUDY DESIGN: This is a retrospective clinical study.

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PATIENT SAMPLE: There were 15 patients included in this study.

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OUTCOME MEASURES: The visual analog scale (VAS) and the

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Japanese Orthopaedic Association (JOA) scores were evaluated. The

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incidence of complications after surgery was also analyzed.

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METHODS: A total of 15 patients including 9 males and 6 females with

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TCS received the homogeneous spinal-shortening axial decompression

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(HSAD) from September 2011 to February 2015. The average age at the

Affiliations: All authors are from the Department of Orthopaedic Surgery, Changzheng Hospital, Shanghai, China. Corresponding Author: Jiangang Shi, Ph.D* . Mailing Address for corresponding author: Department of Orthopaedic Surgery, Changzheng Hospital, No. 415 Feng Yang Road, Shanghai 200003, China; Phone: 8613701668346 Fax:86-021-63520020 E-mail: [email protected] Disclosure: No fund was received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript

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time of surgery was 38.1 ± 17.7 years. The average postoperative

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follow-up period was 21.5±7.5 months. The VAS and JOA scores were

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used to evaluate clinical effects of the new operational procedure. In

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addition, the incidence of complications was also recorded and analyzed.

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RESULTS: The VAS scores decreased from 3.93±2.52 to 1.80±1.21 at

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final follow-up after surgery with significant statistical difference

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(p=0.006). The JOA scores also significantly increased from 9.93±3.43 to

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21.20±4.18 at the final follow-up (p<0.001). Fourteen cases (93.3%) with

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bladder dysfunction and 7 cases with sensory dysfunction of lower limbs

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（ 87.5% ） had

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complications such as infection, pulmonary embolism, nerve injury, rod

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broken, etc were not observed during the follow-up period.

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CONCLUSIONS: The operation of HSAD was an effective and safe

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surgical method for TCS, which can achieve direct decompression of the

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tethered spinal cord.

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Introduction

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Tethered cord syndrome(TCS) is a series of syndromes caused by the end

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of the spinal cord which is fixed to the spinal canal and limits its activity.

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According to an uncompleted statistic, there were approximate 4 million

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cases with TCS in China alone [1].

significant

improvement

postoperatively.

The

Keywords: tethered cord syndrome; surgical treatment; homogeneous spinal-shortening and axial decompression

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The abnormal axial stretch of end of the spinal cord is considered to

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be the pathological mechanism of the tethered cord syndrome [2]. The

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sectioning of filum terminale can directly release the spinal cord tethered

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by abnormal filum terminale, which has been considered to be the gold

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standard treatment of TCS for a long time [3-7]. However, this type of

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surgical treatment requires opening the dural sac and therefore rates of

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the related complication such as cerebrospinal fluid leakage, spinal

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infection and the iatrogenic cauda equina injury, etc were higher [8-11]. 2 Page 2 of 23

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In addition, the re-tethered of the spinal cord due to the postoperative

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adhesion is also an important issue affecting the efficacy of this type of

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surgery [1]. Therefore, to develop an effective surgical treatment with

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minimal complications is of great significance for the TCS.

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Based on many years of surgical treatment on TCS, we firstly

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developed

a

new

type

of

operational

method,

homogeneous

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spinal-shortening and axial decompression(HSAD), for cases with TCS.

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By partial resection of the lumbar intervertebral discs, we uniformly

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shortened the spine length of patients with TCS to achieve direct

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decompression on tethered spinal cord. The operational procedure was

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significantly simplified compared with the traditional untethered surgery.

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The operation procedure was similar to the conventional lumbar

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discectomy and fusion in spine surgery and easy to perform. Without

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opening the dural sac or osteotomy, the new method effectively avoids

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the shortcomings of traditional surgery in treatment of TCS. Through a

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lot of clinic practice, satisfactory clinical effects were achieved in patients

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with TCS by use of HSAD, and we believe this operational technique was

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the safe and effective surgical treatment for TCS. The objective of this

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retrospective study was to investigate the clinical efficacy of HSAD on

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patients with TCS to provide a promising treatment for such diseases.

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Materials and methods

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Patient populations

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The study group comprised 7 males and 8 females with TCS, which

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underwent the HSAD from September 2011 to February 2015 (Table 1).

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The average age at the time of surgery was 35.1±20.1 years. The

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average postoperative follow-up period was 21.5 ± 7.5 months. All

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patients were adequately informed of the expected and adverse outcomes

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of the surgical trial and their written informed consent was obtained.

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The criteria include: 1) admitted to our department because of

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persistent urinary incontinence despite medical treatment with a possible

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diagnosis of a tethered cord syndrome; 2) magnetic resonance imaging 3 Page 3 of 23

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(MRI) scans showing a low position of the conus, with the conus ending

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below the lower endplate of the L2 vertebral body; and 3) no other

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explanation for the urinary incontinence except a possible TCS.

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During the study, patients who fit the diagnosis of TCS were offered

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the option of HSAD as an unproven but possibly beneficial procedure.

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After discussion of the pros and cons, patients were advised to consider

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the option and decide whether to receive surgery or to continue with

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conservative treatment.

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The study protocol was approved by the Ethics Committee of our

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Hospital. The clinical experiment was performed in accordance with

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relevant guidelines and regulations, and the informed consent to publish

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identifying images was obtained from participants. Data of all patients

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including demographics, age of the surgery, urological findings,

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urodynamic examinations, back or lower limb pain, neurological and

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orthopedic abnormalities were recorded. The level of termination of the

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conus, the size of the filum, the presence of fat in the filum, and other

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associated spinal and spinal cord abnormalities (e.g., a syrinx) were

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determined by MRI scans. In addition, the urodynamic outcomes of all

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patients after surgery at each follow-up visit were also recorded.

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Surgical procedure

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After the success of anesthesia, patients prone on the operating table.

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Take the operated level of L2-L5 for an example. Expose the L2-L5 facet

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joints and lamina of the operated level bilaterally. The L2-L5 pedicle

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screw fixation was performed. After that, the inferior articular process of

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L2 and superior edge of L3 lamina was resected. Subsequently, the

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intervertebral disc of L2/3 were exposed, and the discectomy and fusion

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with autogenous bone was performed. The L3/4 and L4/5 were managed

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at the same way. Slow and uniform compression was applied in each

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operated level. The intraoperative fluoroscopy was used to confirm the

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good position of screws. The operative levels include the upper and lower

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two intervertebral spaces adjacent to the level where the coni medullaris 4 Page 4 of 23

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locates (Figure 1, 2). For the location of coni medullaris lower than S1,

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the operative levels were usually selected as L3-S1. After operation, all

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patients were immobilized in a waist support for 8 to 12 weeks.

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Clinical evaluation

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The plain radiographs and MR images were retrospectively reviewed.

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Gait ability, pain and numbness/tingling sensation, detailed motor and

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sensory functions, and the JOA scores were obtained and evaluated at the

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following time points: immediately before and after surgery, 3 months

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after surgery, 6 months after surgery, 1 year after surgery, and at the final

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follow-up appointment. The operation duration, volume of intraoperative

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hemorrhage, and adverse events were also recorded.

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The levels of shortening were evaluated using the radiological

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examinations. Fusion was considered when the following conditions were

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satisfied: (1) absence of motion between the spinous processes; (2)

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absence of a radiolucent gap between the graft and the endplate; (3)

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presence of continuous bridging bony trabeculae at the graft-endplate

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interface. In addition, the lumbar lordotic angles of patients were also

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measured using the Cobb’s method, which were formed by lines along

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the superior endplate of L1 to superior endplate of S1 in a neutral

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position[12].

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Statistical analysis

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The independent samples T-test is used to compare the means of VAS or

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JOA scores before and after surgery. The results were analyzed by SPSS

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software for Windows (ver. 21.0; SPSS Inc, Chicago, IL, USA) and results

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were considered statistically significant at the p <0.05 level.

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Role of funding source

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No funds were received in support of this study.

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Results

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The follow-up period of patients was 21.5±7.5 months. Five cases of

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TCS were confirmed with intra-spinal lipoma concentrated in L5-S1 and

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7 cases has spinal bifida. Five cases have undergone filum section, in 5 Page 5 of 23

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which the bladder function did not achieve significant changes after

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surgery. Two cases with meningocele have received repair surgery after

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birth, however, symptoms of the two patients were not significantly eased.

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There were in all 11 cases with bladder dysfunction including one case

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with hydronephrosis. Seven cases were diagnosed as intestinal

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dysfunction. Sensory dysfunction of lower limbs and low back pain

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occurred in eight and nine cases, respectively. There were eleven cases

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with motor dysfunction including 2 cases with unilateral foot drop

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(Figure 1, 2). The life quality of all cases has been significantly affected.

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The pathological signs and weakening of tendon reflex occurred in all

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cases.

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The operation time of patients was 265.6±61.0 min and the blood

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loss was 720.0 ± 214.5 ml respectively. The total length of spinal

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shortening was 17.2±2.9mm,and the shortening length of each spinal

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level was 4.2±0.5mm. Significant improvement of motor dysfunction

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and low back pain occurred in eleven (100%) and eight (88.89%) cases

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respectively. The results of the manual muscle tests showed that strengths

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of the tibialis anterior muscle of the patients with motor dysfunction

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significantly improved from the preoperative 3.27±1.16 to postoperative

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4.27±0.59, with a 30.6% increase(Table 2, p <0.05).

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The VAS scores decreased from 3.93±2.53 to 1.8±1.21 at final

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follow-up after surgery with significant statistical difference (p=0.006).

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The JOA scores significantly improved from the 9.93±3.43 to 21.20±4.18

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at the final follow-up after surgery (p<0.001, Table 3). Seven cases with

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sensory dysfunction of lower limbs（87.5%）had significant improvement

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postoperatively. Bony fusion was achieved in all cases without

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pseudoarthrosis formation. The lumbar lordotic angle of patients

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significantly increased from preoperative 35.93±7.63° to postoperative

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41.9±8.08° at the final follow-up(p <0.05).

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The urinary dynamics results showed that patients with TCS

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commonly presented as bladder dysfunction. This was mainly manifested 6 Page 6 of 23

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as low compliance bladder, low stress of leakage spot, decrease of safety

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capacity, weak detrusor and incoordination of sphincter. After HSAD, the

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urinary dynamics results showed the improvement of bladder compliance

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and increase of safety capacity in fourteen cases (93.3%). These patients

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presented as alleviation of the weak detrusor and increase of urine

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volume. The electromyogram results showed significant improvements in

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these cases at the final follow-up, which can diastole the sphincter in

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conjunction with urination.

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Discussion

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The mechanism of TCS was thought that it was associated with the

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abnormal axial traction of coni medullaris by thickened fila terminale [2].

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The fila terminale section to directly decompress the tethered spinal cord

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was regarded as the gold standard for surgical treatment of TCS [3-7].

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It was reported that the remission rate of TCS cases with bladder

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dysfunction and pain relief was 38.5%–61% and 81%–91% respectively

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by fila terminale section [3-7]. In addition, the motor function of 44%-70%

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cases with TCS can be restored by this type of surgery [3-7].

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Although certain clinical effects can be achieved by fila terminale

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section, there are still 5-50% patients with re-tethered syndromes after

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surgery [1]. If the fila terminale section was performed again on these

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patients, the incidence of complications is also increased. We consider

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that indications of the traditional surgical treatment for TCS were

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relatively narrow. In theory, it is only suitable for TCS patients caused by

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simple traction of fila terminale[13]. Although construction of animal

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model with TCS by traction of fila terminale has been reported, it was

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still quite different from the cases with TCS[14]. We believe that the fila

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terminale section could make partial spinal cord move up and therefore

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increase the tension of cauda equine, which is also an important cause of

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the secondary damage to the nervous tissue. Therefore, fila terminale

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section can not only be unable to achieve the complete decompression of

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the nerve tissue but also lead to the aggravation of the symptoms. 7 Page 7 of 23

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Although the fila terminale is only made up of fibrous connective tissue

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and glial cells, but we believe it can play an important role in stabilizing

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the normal physiological position of spinal cord and cauda equine[15-17].

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If the fila terminale was sectioned, it could cause cauda equine

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derangement, which is also an important cause of re-tethered symptoms.

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After untethering surgery, the neurologic recovery with regard to

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pain and neurologic deficit shows great variation, with improvement rates

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ranging from 0 to 100% [18]. For TCS in adults, original tethering

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pathologies including postrepair myelomeningocele, terminal filum

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lipoma, tight terminal filum, lipomyelomeningocele, conus lipoma and

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split cord malformation were found to affect the clinical outcome after

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untethering[19]. Patients with these tethering pathologies have been

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found to have a 9 to 50% chance of worsening pain and sensorimotor

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deficits after untethering[20]. In addition, re-tethering of the spinal cord

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from normal scar formation or arachnoid adhesions after the untethering

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surgery is also an issue for the surgeon to be concerned about, and adults

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with degenerative changes could further complicate the surgical treatment.

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Furthermore, the untethering surgery has complications such as

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cerebrospinal fluid leakage and neurologic deterioration, which have been

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frequently reported[18]. Therefore, untethering surgery is not always a

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suitable treatment.

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The theoretical basis of the spine-shortening osteotomy for TCS is to

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indirectly decompress the tethered spinal cord by shortening the length of

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spine [21]. Kokubun firstly reported the single level spine-shortening

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osteotomy on patients with TCS, which achieved satisfactory clinical

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effects [22]. However, it was easy to cause spinal cord injury with a

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single level osteotomy. The single level osteotomy usually has

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disadvantages of limited length of osteotomy, which can not reach

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satisfactory curative effect.

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In addition, the trauma caused by osteotomy shortening method was

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relatively large, and the length of spine shortening is usually limited with 8 Page 8 of 23

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the single segment of the osteotomy, which can affect the efficacy of

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surgery. In the meanwhile, the single-level osteotomy also could not

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achieve effects of uniform decompression of the spinal cord. It is also

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difficult to perform multi-level osteotomy which can result in long

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operation time, large amount of intraoperative bleeding, and high surgical

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risk. The multi-level osteotomy could also damage the spine stability.

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Based on long-term clinical experience in treatment of TCS, we put

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forward a hypothesis of the TCS pathogenesis that the tethered injury of

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the low spinal cord could result from the congenitally differential

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development of the spine and nerve tissue instead of the fila terminale

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traction

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spinal-shortening and axial decompression (HSAD) surgery on patients

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with TCS. To achieve the direct decompression of the tethered spinal cord,

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the length of the spine of the TCS patients is reduced by the partial

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resection of the lumbar intervertebral disc tissue and compression by

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pedicle screw system. Through HSAD, the direct decompression of the

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tethered spinal cord was achieved and the spine length of TCS patients

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was reduced homogeneously. The operation process is obviously

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simplified compared with the previous treatment methods, and the

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procedure is similar to the routine lumbar disc resection in spine surgery.

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Therefore, the learning curve for spine surgeons is greatly shortened, and

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it is not necessary to open the dura mater or perform osteotomy, which

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effectively avoid the shortcomings of traditional surgery. In addition,

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without vertebral osteotomy, advantages of HSAD also include shorter

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operation time, less bleeding and trauma. Through a large amount of

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clinical practice, we consider that this innovative surgical strategy is safe

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and effective, and can be an alternative to fila terminale section in

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surgical treatment for TCS.

[1].

We

further

firstly

perform

the

homogeneous

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In our series, the improvement of urination dysfunction occurred in

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14 cases (93.3%) after HSAD. In addition, the postoperative pain in the

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waist and lower limb of patients after HSAD are greatly ameliorated. The 9 Page 9 of 23

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motor function of all patients also recovered to the normal level. There

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were two cases with transient decline of lower extremity motor function

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postoperatively which could be associated with the stimulation of the

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tethered spinal cord during operation. The function of lower limbs of

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these two cases recovered completely after 2 weeks postoperatively. The

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complications such as infection, pulmonary embolism, nerve injury, rod

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broken, etc were not observed during the follow-up period.

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The spinal shortening must be performed under electrophysiological

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monitoring. In order to achieve uniform shortening, we adopted the

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partial resection of the intervertebral disc and performed compression

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with rod-screw system. Single segment of spinal shortening can not

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improve the spinal cord traction in other segments. In the meanwhile, the

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single segmental spinal shortening is easy to cause local excessive

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shortening and cause iatrogenic spinal cord injury. Through 4-5mm of

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shortening at each intervertebral space, the cumulative effects of multiple

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segments can finally achieve the uniform and adequate axial

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decompression of the tethered spinal cord. To our clinical experience,

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15-25mm spinal shortening in the thoracolumbar region can acquire

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satisfactory decompression effects.

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Compared with the traditional surgery of fila terminale section,

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HSAD has the following advantages: 1. It can achieve the uniform

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decompression of the tethered spinal cord by multi-level intervertebral

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disc resection and compression, which is simple to learn and easy for the

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spine surgeon to operate. 2. Without opening the spinal canal, the

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incidence of iatrogenic spinal cord injury, spinal infection, and the

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occurrence of re-tethered syndrome was reduced to the maximum.

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The indications of HSAC are as follows:1. intraspinal lipoma; 2.

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spina bifida with lipoma myelomeningocele; 3. postoperative adhesion of

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traditional surgery for TCS; 4. cases with difficulty in untethering the

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spinal cord. Finally, the aggravation of TCS symptoms caused by tumor

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or congenital neural structure defect is the relative contraindication to the 10 Page 10 of 23

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HSAD. The main limitation of HSAD is that multi-level spinal fixation

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could reduce the lumbar spine mobility. However, we believe that it is

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worthy to achieve improvements in neurological function and life quality

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at the expense of spinal motion loss. Furthermore, the movement of hip

5

joint can compensate for the loss of spinal mobility without influencing

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the life quality of patients with TCS.

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The current study includes the following limitations: 1) this is a

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retrospective review; 2)the number of patients with TCS is relatively low;

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3) there is a lack of the control group using the untethering surgery or

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osteotomy. Thus, it is difficult to assess the clinical efficacy of HSAD

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between the cases with initial TCS and those with recurrent TCS, and

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between the cases underwent HSAD and those underwent other surgical

13

treatments. Therefore, the current clinical study can not demonstrate that

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the HSAD should be considered as the first surgical option for TCS. The

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prospective randomized large-scale studies are required to further

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evaluate the clinical effects of HSAD in comparison to the conventional

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untethering surgery for TCS in the future.

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Contributions

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Yang Hou. wrote the manuscript with all authors commenting. Yang Hou,

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Jiangang Shi, Jingchuan Sun and Yuan Wang performed the clinical

22

experiment. Guodong Shi, Guohua Xu and Yongfei Guo participated in

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data analyses. Yang Hou and Jiangang Shi designed the research.

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Declaration of interests We declare no competing interests.

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Acknowledgements

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We thank our clinical colleagues for referrals to the study; and the

29

research support teams who provided helpful assistance throughout the

30

study.

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[12] Lin RM, Jou IM, Yu CY. Lumbar lordosis: normal adults. J Formos Med Assoc 1992;91:329-33. [13] Yong RL, Habrock-Bach T, Vaughan M, et al. Symptomatic retethering of the spinal cord after section of a tight filum terminale. Neurosurgery 2011; 68: 1594-601. [14] Huang SL, Peng J, Yuan GL, et al. A new model of tethered cord syndrome produced by slow traction. Sci Rep 2015; 5:9116. [15] Kwon M, Je BK, Hong D, et al. Ultrasonographic features of the normal filum terminale. Ultrasonography 2017; Jun 8. [16] De Vloo P, Monea AG, Sciot R, et al. The Filum Terminale: A cadaver study of anatomy, histology, and elastic properties. World Neurosurg 2016; 90:565-573. [17] Gaddam SS, Santhi V, Babu S, et al. Gross and microscopic study of the filum terminale: does the filum contain functional neural elements? J Neurosurg Pediatr 2012; 9:86-92. [18] Nakashima H, Imagama S, Matsui H, et al. Comparative study of untethering and spine-shortening surgery for tethered cord syndrome in adults. Global Spine J 2016;6:535-41. [19] Van Leeuwen R, Notermans NC, Vandertop WP. Surgery in adults with tethered cord syndrome: outcome study with independent clinical review. J Neurosurg 2001; 94:205-9. [20] Lee GY, Paradiso G, Tator CH, et al. Surgical management of tethered cord syndrome in adults: indications, techniques, and long-term outcomes in 60 patients. J Neurosurg Spine 2006;4:123-31. [21] Hsieh PC, Stapleton CJ, Moldavskiy P, et a1. Posterior vertebral column subtraction osteotomy for the treatment of tethered cord syndrome: review of the literature and clinical outcomes of all cases reported to date. Neurosurgical focus 2010; 29: E6. [22] Kokubun S. Shortening spinal osteotomy for tethered cord syndrome in adults. Spine Spinal Cord 1995; 8 Suppl 12:5.

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Figure legends: Figure 1: A 10-year-old female patient, who underwent intra-spinal lipoma resection after birth, presented with weakness of bilateral lower limbs, poor urine control and unilateral food drop for 11 years (Fig 1a). The preoperative MRI showed that the conus medullaris located at L3 (Fig 1b). The preoperative spinal model of the patient showing the spinal bifida (Fig 1c). The lateral and anteroposterior radiography of this case after HSAD (Fig 1d, e). After the HSAD, the urination function of the patient was largely restored. She can control the urination except that a small amount of urine leakage occurred when laughing and sneezing. In addition, the plaster immobilization was used for foot drop and the motor function of lower limb recovered well (Fig 1f). Figure 2: A 9-year-old male, who underwent the intra-spinal lipoma resection after birth (Fig 2a), presented with enuresis and urinary incontinence for 10 years. The patient also had unilateral foot drop and lower extremities pain. The location of conus medullaris was at L3 according to preoperative MRI (Fig 2b). The spinal bifida was also diagnosed by the three-dimensional CT reconstruction (Fig 2c). The lateral and anteroposterior radiography of this case after HSAD (Fig 2d, e). The composite image of the preoperative and postoperative median sagittal reconstruction image (Fig 2f), with the red color of preoperative spine and the green color of the postoperative spine. After overlapping the L5, the shortening length of the spine can be calculated by the height distance between the preoperative and postoperative L1.

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1

Table 1: Demographic data of patients with tethered cord syndrome(TCS) Case

Gender

Age

number

Position of

urinary

Clinical

History of filum

conus

dysfunction

abnormalities

terminale section

medullaris

other than urinary dysfunction

1

Female

58

L2/3

Normal

Spinal lipoma

No

2

Female

51

L5

Normal

Spina bifida

No

3

Female

57

L2/3

Normal

4

Male

57

L5

Small

Weakness of

capacity,

lower limbs

No No

poor compliance 5

Female

64

L5

Small

Fecal

capacity,

incontinence,

poor

Spina bifida

No

compliance 6

Female

18

L5

Small

Spina bifida,

capacity,

bilateral

poor

hydronephrosis

Yes

compliance 7

8

Male

Male

43

32

L5/S1

S1

Small

Fecal

No

capacity,

incontinence,

poor

Spinal lipoma,

compliance

Spina bifida,

Small

Spinal lipoma

No

Large

Fecal

Yes

capacity,

incontinence,

insensate

Spinal lipoma,

bladder

Spina bifida

Small

Fecal

capacity 9

10

Male

Female

10

34

L4

S1

No

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capacity,

incontinence

poor compliance 11

Male

9

L3

Small

Foot drop

Yes

Small

Fecal

No

capacity,

incontinence,

poor

Spina bifida

capacity, poor compliance 12

Male

28

L3

compliance 13

Female

45

L3

Normal

Syringomyelia

No

14

Female

10

L3

Large

Fecal

Yes

capacity,

incontinence,

insensate

Foot drop

bladder 15

Male

10

L3

Large

Fecal

capacity,

incontinence,

insensate

Spinal lipoma,

bladder

Spina bifida

Yes

1 2

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1 2

Table 2: The VAS scores and MMT test results of patients with TCS before and after surgery Case

Preoperat

Postoperat

Postoperat

Postoperat

Postoperat

Preoperat

Postoperat

numb

ive

ive

ive

ive

ive

ive

ive

er

VAS

VAS

VAS

VAS

VAS

tibialis

tibialis

scores

scores at

scores at

scores at

scores at

anterior

anterior

3-month

6-month

12-month

final

muscle

muscle

follow-up

follow-up

follow-up

follow-up

strength

strength at final follow-up

1

5

4

4

3

2

5/5

5/5

2

0

0

0

0

0

5/5

5/5

3

8

5

5

4

2

5/5

5/5

4

6

3

3

2

1

3/5

5/5

5

5

3

3

3

3

3/5

4/5

3

2

2

1

1

3/5

4/5

7

4

2

2

2

2

2/5

4/5

8

6

4

4

4

3

5/5

5/5

9

0

0

0

0

0

2/5

3/5

10

0

0

0

0

0

3/5

4/5

11

6

4

4

4

4

2/5

4/5

12

5

3

3

2

2

3/5

4/5

13

6

4

3

3

3

3/5

4/5

14

2

2

2

2

2

2/5

4/5

15

3

2

2

2

2

3/5

4/5

6

3 4

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1

Table 3: The JOA scores and urodynamic findings of patients with TCS before

2

and after surgery Case

Preoperat

Postoperat

Postoperat

Postoperat

Postoperat

Preoperat

Postoperat

numb

ive

ive

ive

ive

ive

ive

ive

er

JOA

JOA

JOA

JOA

JOA

Urodyna

Urodynam

scores

scores

mic

ic findings

findings

at

at

scores

at

scores

at

scores

at

3-month

6-month

12-month

final

follow-up

follow-up

follow-up

follow-up

final follow-up

1

2

14

16

23

23

25

23

25

26

26

26

Small

Improved

capacity,

capacity

poor

and

complian

complianc

ce

e

Small

No change

capacity,

in

poor

capacity,

complian

complianc

ce

e improved

3

4

15

12

22

18

22

20

26

22

26

24

Small

Improved

capacity,

capacity

poor

and

complian

complianc

ce

e

Small

Improved

capacity,

capacity

poor

and

complian

complianc

ce

e

18 Page 18 of 23

5

6

7

8

11

5

12

12

10

16

13

18

20

15

22

22

15

22

Small

Improved

capacity,

capacity

poor

and

complian

complianc

ce

e

Small

Improved

capacity,

capacity

poor

and

complian

complianc

ce

e

Small

No change

capacity,

in

poor

capacity,

complian

complianc

ce

e improved

8

10

12

14

19

20

Small

Small

capacity

capacity improved

9

8

8

10

14

14

Large

No change

capacity, insensate bladder 10

12

12

14

15

15

Small

Improved

capacity,

capacity

poor

and

complian

complianc

ce

e

19 Page 19 of 23

11

12

13

14

15

8

9

10

5

6

12

13

18

12

14

15

18

22

16

16

17

20

25

19

20

18

22

26

20

22

Small

Improved

capacity,

capacity

poor

and

complian

complianc

ce

e

Small

Improved

capacity,

capacity

poor

and

complian

complianc

ce

e

Small

Improved

capacity,

capacity

poor

and

complian

complianc

ce

e

Small

Improved

capacity,

capacity

poor

and

complian

complianc

ce

e

Small

Improved

capacity,

capacity

poor

and

complian

complianc

ce

e

1 2 3 4

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1 2 3

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1 2 3

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1 2

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