Nghiên cứu đặc điểm lâm sàng, chẩn đoán hình ảnh và kết quả phẫu thuật trượt đốt sống thắt lưng đơn tầng do khe hở eo TT TIENG ANH

MINISTRY OF EDUCATION
MINISTRY OF DEFENSE
AND TRAINING
MILITARY MEDICAL UNIVERSITY

TRAN HONG VINH

RESEARCH ON CLINICAL FEATURES,
DIAGNOSTIC IMAGING AND RESULTS OF
SINGLE-STAGE LUMBAR SPONDYLOLISTHESIS
SURGERY DUE TO SPONDYLOLYSIS
Specialty:

Surgery

Code:

9720104

ABSTRACT OF THE DOCTORAL THESIS IN MEDICINE

HA NOI - 2021


THE THESIS WAS COMPLETED AT
THE MILITARY MEDICAL UNIVERSITY

Science instructor:

A.Prof. PhD. NGUYEN VAN THACH

Reviewer 1: A.Prof. PhD. Nguyen Le Bao Tien
Reviewer 2: A.Prof. PhD. Tran Cong Hoan
Reviewer 3: A.Prof. PhD. Nguyen The Hao

The thesis is defensed in front of the University Thesis Council at
Military Medical University
At:..................on the.... (date) of.... (month), 2021

The thesis may be found at:
- Vietnam National Library
- Library of Military Medical Academy


3
INTRODUCTION
Spondylolisthesis (SPL) is a phenomenon of displacement of the upper
vertebra compared to the adjacent lower vertebra accompanied by complex
pathological changes such as fracture of the pars, degenerative disc joint
mass, and proliferation causing narrowing of the spinal canal and the
synovial hole leading to spinal instability and nerves compression. Lumbar
spondylolisthesis due to many reasons, including spondylolysis accounts for
4-8% of the population and often unstable. Diagnostic imaging plays an
important role in the early diagnosis of this type of pathology. In Vietnam,
the majority of cases of SPL due to spondylolysis when being hospitalized
for treatment have symptoms of nerve compression, lumbar spine pain due
to instability after a long time, affecting the ability to work and quality of
life. However, currently in Vietnam are mainly researches on diagnosis and
treatment of spondylolisthesis in general.
On the other hand, in the surgery of treating SPL due to spondylolysis,
two compulsory criteria are optimal anatomical manipulation, firm fixation

and effective nerve decompression. Considering these two criteria, recently
published studies in the world have demonstrated the superiority in
manipulation, good bone fusion, firm fixation and effective nerve
decompression of the PLIF method.
Therefore, we conduct the topic: "Research on clinical features,
diagnostic imaging and results of single-stage lumbar spondylolisthesis
surgery due to spondylolysis" with two goals:
1. Describing the clinical and visual characteristics of unilateral
spondylolisthesis caused by spondylolysis.
2. Evaluate the results of single-stage spondylolisthesis surgery due to
spondylolysis by using the method of rods and screws fixation combined
with disc decompression, intervertebral fusion.
MEANING OF THESIS
The thesis deals with research on single-level isthmic spondylolisthesis
due to pars fracture, this is a problem of high practical significance in the
current period. Therefore, the thesis has made new contributions in spine
surgery as follows:
+ Affirming the superiority and irreplaceable practical value of PLIF
surgery in isthmic spondylolisthesis when new spinal surgery methods are
deployed and applied in the specialty
+ Contributing to providing a deeper understanding of techniques of
manipulation, decompression, and fusion in surgery for isthmic
spondylolisthesis cases in general and cases with slippage in particular.


4
THESIS STRUCTURES
The thesis has 109 pages, Chapter I - Introduction (33 pages), Chapter II Subject and Method (23 pages), Chapter III - Results (22pages), Chapter IV Discussion (26 pages), Conclusions (1 pages). The thesis has 43 tables, 43
pictures, and 12 charts. The thesis has 136 references, include 8 Vietnamese
references and 126 English references.

CHAPTER 1: OVERVIEW
1.1. Research history
1.1.1. In the world
Lumbar spondylolisthesis was mentioned by Herbinaux in 1782. Then
Kilian came up with a definition and the term spondylolisthesis (SPL). In 1950,
MacNab was the first to introduce a classification system of SPL. Then, Wiltse
in 1957 and Newman in 1963 gave a classification of SPL including 5 types.
However, these classifications are different and inconsistent. Therefore, these
authors agreed with each other and made a new classification which was
reported in 1976 at the international conference on spine named Wiltse Newman - MacNab divided SPL into six different categories. Some studies have
shown a significant relationship between SPL and BMI, age and lordosis of the
spine. According to research by Avanzi O., and colleagues, the rate of SPL most
commonly encountered in L4L5 level, accounts for 47.6%; then to the L5S1
level with the rate of 23.8%; the other is a combination of both L4L5 and L5S1
levels.
In terms of diagnosis, SPL due to many different causes has diverse
clinical manifestations, no specific symptoms, so it is often confused with
disc herniation and spinal stenosis .... Therefore, diagnostic imaging plays a
particularly important role and has made great breakthroughs in the accurate
diagnosis of SPL.
In terms of treatment, in 1933 Burns first described surgical treatment
using bone fusion with anterior intervertebral fusion combined with grafting
technique to treat SPL at the L5-S1 level. Then, a number of authors such
as: Lane and More, Briggs and Milligan, Cloward, Watkins, Gill, Harrington
and Tullos reported that the treatment of SPL by different surgical methods
obtained positive results and positively worked on the basis for later surgical
methods. In particular, good manipulation, firm fixation is the foundation for
strong bone fusion and nerve decompression, thereby allowing to achieve
optimal efficiency in surgery for SPL. Bone grafting has many techniques
applied such as: spondylolysis cleft bone grafting, posterolateral bone

grafting, combined posterolateral grafting and intervertebral bone graft,
anterior and posterior intervertebral bone graft. West et al reported 90% of
bone healing results in bone grafting patients using an internal immobilizer
because the spine is fixed immediately after surgery, so the process of bone


5
resection is favorable, increasing the rate of rate of bone healing. In general,
all direct bone fusion methods are considered to be relatively safe and
effective.
1.1.2. Vietnam
In Vietnam, the diseases of the spine in general and the SPL in particular
have been mentioned and discussed from the 50s of last century. However, it
was not until the second half of the 20th century that the surgical methods of
MSG really developed thanks to the technology and the means of fixing the
spine through pedicles to be applied, opening up the research and treatment
direction for this type of pathology. Since then, the researches on surgical
treatment of SPL began to be mentioned and deployed. Currently, SPL has been
carried out routinely in major departments of nerve - spine across the country.
1.2. Applied anatomy of the lumbar spine
1.2.1. Lumbar vertebrae surgery
Each vertebra consists of the main components of the vertebrae, the
body, the vertebrae arch and the foramen. The pedicle attaches to the
posterior 2/3 at L1 - L5 with wedge angle from L1 - L5 (5° - 15°). The
transverse diameter of the pedicle is smaller, more important than the
longitudinal diameter, and increases gradually from L1 to L5. This is an
important anatomic feature in determining the point and entry of the arched
screw fixing method to create stability for all 3 columns. The pedicle is
stronger and more stable than the body and is the strongest part of the
vertebra that can withstand the force of rotation, stretching and tilting to the

side of the spine. Therefore, most of the means of fixing the spine in the
world are used for screwdriving through the pedicles. The pars
interarticularis is the intersection of the transverse process, lamina and two
facet joints of a vertebral body, which can form a cleft, causing a loss of
posterior arch continuity, which is the main cause of spondylolysis. There
are two forms of pars damage: cleft and pars damage. The majority of
patients have only one level of pars damaged, but can also be found at
several levels of the spine.
1.2.2. Neurologic anatomy of the lumbar region and related structures
Nerve roots go from the spinal canal below the pedicle out through the
intervertebral foramina and near the top of the vertebral pedicle just below.
In which, the correlation of position between the nerve roots passing
through the intervertebral foramina and the disc is divided into four different
positions: the shoulder, the anterior, the axillary, the unrelated type.
The Kambin triangle - "safety triangle" is limited by: the outer edge in
front is the exit root, the lower edge is the upper edge of the lower vertebra,
behind by the upper joint of the lower vertebra and the inner edge is the root
pass. This is a safe area to interfere with the disc when using surgical


6
instruments in the spine. The understanding of the safe zone is necessary so
that when we intervene in this area when root decompression, bone grafting
will minimize complications such as root damage, tear of dura matter.
1.3. Pathogenesis and classification of lumbar SPL.
1.3.1. Pathogenesis
Spondylolysis is a loss of posterior continuity. The cause of
spondylolysis can be traumatic or genetic.
+ Injury theory that spondylolysis is caused by the constantly
movements of folding and stretching the spine causing fracture of the pars,

called fatigue fracture.
+ Injury to the spine can cause pedicle fracture, fracture of joints,
fracture pars, damage the posterior column, leading to unstable spine
causing SPL.
+ Theory of Genetics: Epidemiological studies show that the rate of
spondylolysis is stable in a lineage, an ethnic group.
1.3.2. Classification of spondylolisthesis
Based on the classification of Newman, Macnab, in 1976 Wiltse synthesized and
categorized SPL into six different types: congenital numbness, spondylolysis SPL,
degenerative SPL, traumatic SPL, pathological SPL, post-operative SPL. In which, the
SPL due to spondylolysis includes:
+ Sub-group 2 A: Type of pars defect identified as due to fatigue fracture.
+ Sub-group 2 B: This type of sliding pars is longer than normal. This
elongation is explained by the phenomenon of fractures and bone healing
that occurs continuously in the pars area.
+ Sub-group 2 C: Injury that causes pars fractures leading to slippage.
1.4. Clinical and diagnostic imaging in spondylolisthesis
1.4.1. Clinical lumbar spondylolisthesis
There are valuable clinical signs in assessing the state of spinal
instability, the majority of patients with SPL have clinical symptoms
manifested by two syndromes:
+ Spine syndrome: characteristics of movement-related pain and positive
ladder sign.
+ Nerve root compression syndrome: with regional manifestations of the
pinched nerve root.
1.4.2. Methods of diagnostic imaging
1.4.2.1. Standard X-ray
It is a simple and effective diagnostic method in detecting SPL. Usually
apply frontal, oblique, 3/4-lateral and dynamic X-rays to help assess the

7
unstable state of the spine, the degree of slippage of the vertebra and detect
other spinal deformations. In specific:
* Oblique position
Films at a tilted position are an effective method for assessing the degree
of SPL. Meyerding based on a oblique-X-ray film divided SPL into four
degrees:
+ Grade I: the upper vertebral column deviates within 1/4 of the
anteroposterior diameter of the lower vertebral body.
+ Grade II: the upper vertebrae slide from 1/4 to 1/2 of the
anteroposterior diameter of the lower vertebral body.
+ Grade III: the upper vertebrae slide from 1/2 to 3/4 of the
anteroposterior diameter of the lower vertebral body.
+ Grade IV: the upper vertebrae has displacement greater than 3/4 of the
anteroposterior diameter of the lower vertebral body.
On oblique X-ray of the spine, many angles have been determined to describe
in detail the anatomical lesions of the sacrolumbar spine of the patient that affect
the process of SPL. Specifically, the most important indicators are:% of the
slippage forwards according to Taillard, the sliding angle according to Boxall,% of
the curvature of the sacral apex. These three measurable indices allow an
estimation of the risk of the sliding process. High sliding angles with rounded
sacral arches increase the risk of progressive slip especially in children.
Oblique dynamic X-ray
Dynamic lumbar x-ray is a valuable method in determining the
instability of the spine segment. Two main criteria for evaluating the biomechanics of the lumbar spine are slippage and angular folding.
According to White A.A. and Panijabi M.M. to determine vertebral
instability based on the following indicators:
Front and posterior displacement: A is the sliding distance of the upper
vertebra from the lower vertebra. B is anteroposterior diameter of the upper

vertebrae. If A> 4.5mm or A / B x 100%> 15%, then the spine is unstable.
Angle of rotation: the determination is based on the angle of folding and
maximum stretch, where A is the intervertebral angle at maximum flexion
(positive angle), B is the extension angle (negative angle). If A-B> 150, then lost of
stability at L1L2, L2L3, L3L4 levels, if> 200 then the L4L5 layer unstable, if> 250
then L5S1 will be stability lost.
* Lateral position
Most cases are easily detected with spondylolysis. An x-ray image of the
discontinuity is a scotty dog. Most patients have only one pars fissure at one
vertebral level, but may also several levels of vertebrae. According to
Herkowitz H.N, lateral films can detect 19% of pars defects, while lateral
film with reasonable angle can detect up to 84% of the spondylolysis.
1.4.2.2. Computer tomography of the lumbar spine


8
Computerized tomography (CT) has a high sensitivity to detect bone
defects. In which, it is possible to accurately detect the very narrow fracture
line in the pars area, especially new pars fractures due to trauma, pars
defects as well as joint enlargement and anatomy of the pedicle (size,
direction, curvature).
1.4.2.3. Magnetic resonance imaging of the lumbar spine
According to Clayton NK, and Rudiger K., typical images of SPL on
MRI film include: images of the above SPL, spurious disc herniation,
degenerative disc at the position of slipping and adjacent vertebrae, modic,
tearing fibrosis cushion, narrowing of intervertebral foramina; osteoarthritis
on the upper facet joint, hypertrophy of the joints, stenosis of the spinal cord
compressing the cauda equina, low clinging spinal cord (rare) .... In patients
with spondylolyisis SPL, the distance from the posterior edge of the
vertebral body sliding to the anterior margin of the posterior arch increases

on the slice through the midline, which is called a broad spinal sign. This is
an important sign to distinguish between spondylolysis SPL and
degenerative SPL due to the accompanying spinal stenosis.
According to Pfirrmann et al. (2001) evaluated disc degeneration on
MRI based on T2W film and divided into 5 degrees:
Grade I: disc is homogeneous, white signal intensity and normal disc height.
Grade II: disc is inhomogeneous, white signal intensity, normal disc height.
Grade III: disc is inhomogeneous, gray signal intensity, little decreased
disc height.
Grade IV: disc is inhomogeneous, gray to black signal intensity, disc
height is greatly reduced.
Grade V: disc is inhomogeneous, black signal intensity, loss of disc height.
All structures from the simple to the complex of the spine can be
assessed in detail on high resolution magnetic resonance film. Furthermore,
MRI is a non-intervention, uncomplicated diagnostic method. Therefore,
this is the most commonly used diagnostic imaging method to diagnose SPL
along with conventional X-rays.
1.5. Some basic problems in lumbar spondylolisthesis surgery
Surgery of SPL with the aim of decompressing, manipulating, and firmly
fixing the sliding spine in order to restore maximum nerve function and
structure of the damaged spinal segment. Research by Möller H. and
Hedlund R. has shown that the surgery of SPL in adults gives better results
than physical therapy.
1.5.1. Indicated for surgery
- Indications for absolute surgery: nerve compression causes manifestations of
increased nerve damage, progressive slide in children (elevation slide in children,
hunchback and lumbar distortion).


9

- Indications for relative surgery: there are manifestations of nerve
compression but adequate, systematically medical treatment in 6 weeks;
Factors that cause spinal instability: pars defect; Neurological function
decreases and does not improve with conservative therapy.
1.5.2. Pedicle screw
+ The position of the entry point of the lumbar vertebral pedicle
according to Molinari R.W .: is the intersection between a vertical line
tangent to the outer edge of the upper joint with a horizontal line passing in
the center of the transverse process or 1mm below this point. Clinically, the
pedicle entry point is determined at the junction between the surface of the
upper joint, the transverse process and the interarticular junction
corresponding to the nipple process.
+ Direction of screws on the horizontal plane at an angle of about 5º 10º at L1, 10º at L2 and 15º at L3 - L5.
+ The diagram of screwdriving includes straight diagram (considering
the vertical plane of the pedicle screw direction parallel to the top surface of
the body, ie the angle of down to 0º) and anatomical diagram (the screw
direction along the pedicle is about 20º - 25º down). In it, according to
Kuklo T.R. Straight diagrams provide a superior biological mechanism
compared to screwdriving according to anatomical diagrams.
1.5.3. The degree of manipulation of spinal deformities
The current view of correction of spinal deformities is relatively unified.
The manipulation of spinal deformities in patients with low slippage grades
is less commonly reported. For SPL with great slippage, the view to partially
rectify the deformations of the spine contributes to increase the rate of bone
healing, reduce the rate of prosthetic joints and the secondary deviation is
relatively uniform. In general, the authors have the view that they do not try
to rectify the maximum slip. Complete manipulation of the deviations is
difficult to perform and comes with a higher risk of nerve damage. The
general principle of this technique is to stretch the spine to rectify the
angular displacement and pull the vertebrae to slide out after the

manipulation of slip deviation, then the manipulation technique is done
more easily and safely.
1.5.4. Nerve decompression and bone fusion
In SPL, nerve compression can be caused by many reasons: herniated
disc, bony spine, upper posterior margin of the vertebral body, the fibrous
organization of the pars compresses nerve roots in the lateral region or
degenerative enlargement of the joints. However, the site of nerve
compression is more common in the lateral margins and intervertebral
foramina regions. According to Edelson J.G. and surgical associates, need to
perform concurrent bone grafting and decompression of pinched nerve


10
roots. The degree of suppression is also a controversial topic. Since
decompression of a pinched nerve root often increases spinal instability, the
extent of decompression depends on the type of technique used. Authors
who do not have bone grafts or do not use bone fusion media generally do
not release a root compression or only minimal release of compression. John
D.M. and colleagues suggest that loose posterior arch removal is not enough
to release pinched nerve roots. Decompression should include release of
pinched nerve roots in the intervertebral foramina, especially in patients
with neural root pain. However, it should be noted that after the roots are
identified, all proliferating prosthetic joint tissue must be removed.
Vertebrae is shown to be a method with a high rate of bone fused thanks
to its wide bone graft area and rich blood supply, in many studies it can
reach 93% - 100. Vertebral body is the location near the axis of movement
of the spine, where about 80% of the pressure is applied to the spine.
Therefore, this is the most physiological bone grafting technique, ensuring
the stability and conforming to the bio-mechanical properties of the spine.
The result of bone healing eliminates movement between vertebrae, nerve

roots are not stretched during movement, so it does not cause pain due to
sticky scars. There are two popular techniques: PLIF - Posterior Lumbar
Interbody Fusion and TLIF- Transforaminal Lumbar Intervertebral Fusion.
In particular, the PLIF method has the advantage of thoroughly
decompressing and rectifying, especially for large SPL such as grade III,
grade IV when TLIF method has no indication for intervention.
Current bone grafting materials include two types that are commonly used and
combined in surgery: autologous bones and artificial materials such as bone cages,
artificial implants, artificial bone powder.
CHAPTER 2: SUBJECTS AND METHODS OF RESEARCH
2.1. Research subjects
The study was conducted on 51 patients diagnosed with single-story
lumbar SPL and surgical treatment at the Department of Spinal Surgery, Viet
Duc Friendship Hospital from June 2015 to June 2019.
2.1.1. Selection criteria
- Patients aged 18 years and over, have meticulously clinically examined
results and have necessary paraclinical results qualified to diagnose
unilateral lumbar SPL due to spondylolysis, undergo surgery by the method:
disc removal to decompress, inter-body bone grafting, spine fixation by
screws through the pedicle.
The patients were evaluated and monitored at the time: when
hospitalized, immediately after discharge and the last visit (≥ 12 months
after surgery).


11
2.1.2. Exclusion criteria
Patients who do not meet the selection criteria, do not comply with follow-up
visits at specified times, osteoporosis T-score less than or equal to -2.5; congenital
or chronic disease affecting the results of the study.

2.2. Research methods
2.2.1. Research design
- A prospective study on clinical description with intervention,
evaluating the results of each patient before and after surgery.
2.2.2. Sampling method and sample size calculation
The study applies the sample size formula for a ratio:
n=
In which:
- n: Sample size
- Z1-α/2: Confidence coefficient, choose α = 0.05, corresponding to 95%
confidence, we have value of Z1-α/2is 1.96.
- d: Absolute accuracy, choose d = 15%.
- p: The recovery rate of patients with lumbar SPL after surgery
according to research by Okuda S. in 2014 was 73% [97].
Calculated with the formula, n = 34. In fact, 51 patients have been
selected to participate in this study.
2.2.3. The method of data collection
Information collected according to the uniform medical record form includes:
questioning, examination and assessment of patients before surgery; Participate in
surgery and follow-up and treat patients after surgery; Directly examine and
evaluate postoperative patients according to research records at the time: at
discharge and at the last visit for ≥ 12 months.
2.2.4. Research content
Evaluate before surgery, after surgery at the time of discharge and the
last visit according to the criteria on the research diagram.
2.2.5. Data processing and analysis
Data after being entered using Epidata 3.1 software was checked,
cleaned, and analyzed using Stata 15.0 software.
2.2.6. Ethics in research
The study was approved by the Board of Directors of Viet Duc

Friendship Hospital, Leadership Department of Spinal Surgery - Institute of
Orthopedic Trauma, with the consent of patients and their families. All
personal information of the subjects participating in the study is confidential
and used only for research purposes

RESEARCH DIAGRAM


12

Lumbar spondylolysis SPL cases underwent PLIF

Clinical-paraclinical features

Gender

Causes

Conventional X-ray

Slippage

Results

VAS

Symptoms

JOA

ODI

Dynamic X-ray

MRI

During operation

Xray

Duration

After operation

Blood infusion

Fibrosis and defects of Stenosis
pars
Pars defect Flexion angle
Extension angle SlippageDisc degeneration

Discharge
(7-10 days)

JOA

VAS

ODI

≥ 12 months

Fixation results Screws, grafts location
Complications and sequelae


13
CHAPTER 3: RESEARCH RESULTS
3.1. General characteristics of patients
3.1.6. Reasons for admission and location of lumbar spondylolisthesis
Figure 3.7. Reasons for admission
Figure 3.8. Location of lumbar spondylolisthesis
3.1.7. Medical treatment before surgery
Figure 3.9. Medical facilities selected for treatmet
3.1.8. Time of disease progression
Table 3.3. Time of disease progression
Progression time
Number (n)
Rate (%)
< 3 months
6
11,76
3 - 12 months
12
23,53
20
39,22
12 - 36 months
> 36 months
13

25,49
Overall
51
100
3.2. Clinical symptoms and preoperative imaging
3.2.1. Clinical symptoms
3.2.1.1. Mechanical symptoms
Table 3.4. Preoperative mechanical symptoms
Mechanical symptoms
Numbers (n) Rates (%)
Back pain
50
98,04
Lumbar spine loss of function
30
58,82
Nerve roots pain
Unilateral
28
54,90
Bilateral
19
37,25
Interval pain
< 100 m
27
52,94
100 - 500m
8
15,69

> 500 m
1
1,96
3.2.1.2. Examined symptoms
Table 3.6. Preoperative examined symptoms
Examined symptoms
Ladder sign

Number
s (n)
26

Rates
(%)
50,98


14
Paraspinal muscles stiffness
Positive Lasègue < 30
sign
30-70
> 70
Dysthesia
Sensory
Hypoesthesia
disturbances
Dysthesia and hypoesthesia
Motion
Obvious muscle weakness

disturbances along Mild muscle weakness
nerves distribution Normal

38
11
31
8
22
5
23
0
5
46

74,51
21,57
60,78
15,69
43,14
9,80
45,10
0
9,80
90,20

Table 3.7: Evaluate lumbar spinal function according to preoperative ODI
ODI
Grade 2
Grade 3
Grade 4

n
1
39
11
%
1,96
76,47
21,57
3.2.2. Preoperative images
Table 3.10. Conventional and dynamic X-ray
Grades of slippage
Number (n)
Rates (%)
Grade 1
16
31,37
Conventional X-ray Grade 2
28
54,90
Grade 3
7
13,73
Grade 1
8
15,69
Grade 2
23
45,10
Dynamic X-ray
Grade 3

15
29,41
Grade 4
5
9,80
Table 3.11. Evaluate the spinal instability on dynamic X-ray
Criteria
Forward >4,5mm
Tilted > 25⁰
Overall
n
%
n
%
n
%
Grade I
8
50
8
50
16
100
Grade II
15
53,57
13
46,43
28
100

Grade III 2
28,57
5
71,43
7
100
Table 3.12. MRI image
Presentations
Number (n)
Rate (%)
Slip degenerative disc
48
94,12
Adjuvant degenerative disc
39
76,47
Pars defects
40
78,43
Intervertebral foramina stenosis
38
74,51


15
Articular hypertrophy
33
64,71
3.3. Treatment results
3.3.2. Surgery outcomes at time of discharge

3.3.2.1. Clinical symptoms and signs
Table 3.16. Mechanical symptoms
Mechanical symptoms
Numbers
Rates (%)
(n)
Back pain
51
100
Lumbar spine loss of function
18
35,29
Unilateral
35
68,63
Nerve root pain
Bilateral
9
17,65
Interval pain
1
1,96
Table 3.17. Clinical symptoms
Numbe Rate
Clinical symptoms
r (n)
(%)
Positive
< 30
1

1,96
Lasègue sign
30-70
14
27,45
> 70
30
58,82
Sensory
Dysthesia
37
72,55
disturbances
Hypoesthesia
8
15,69
Dysthesia
and
6
11,76
hypoesthesia
Motor
Obvious muscle weakness
0
0
disturbances along Mild muscle weakness
2
3,92
nerves distribution Normal
49

96,08
3.3.2.2. Evaluation of lumbar spinal motor function
Figure 3.10. Evaluate lumbar spinal function according to ODI after surgery
3.3.2.3. Sliding degree on conventional oblique X-ray
Table 3.11. Grades of slippage on X ray
3.3.2.4. Screw and graft examining
Table 3.18. Evaluate screw accuracy according to Lonstein
Criteria
Numbers
Rate (%)


16
(n)
Screws to the upper pedicle edge and
4
1,96
to the upper edge of the body
Screws down the lower edge of
2
0,98
pedicle
Screws to more than 2 times of body
3
1,47
edge on oblique X-ray
Standard screws
195
95,59
Overall

204
100
Table 3.19. Bone grafts location.
Graft location
Number (n)
Rate (%)
Good
48
94,12
Average
3
5,88
Overall
51
100
3.3.3. Evaluate surgical results at the last visit
3.3.3.1. Evaluate clinical signs and symptoms
Table 3.30. Postoperative mechanical symptoms improvements
Preoperative
Last visit
Clinical symptoms
p
n
%
n
%
Lower back pain
50
98,0
42

82,35
0,029
4
*
Nerve root pain
47
92,1
18
35,29
0,124
6
(*) Fisher-exact test

Table 3.31. Postoperative clinical symptoms improvements
Preoperative
Last visit
p
Clinical symptoms
n
%
n
%
Positive Lasègue sign 50
98,04
8
15,69 0,019
*
Sensory disturbances 50
98,04
9

17,65 0,640
(*) Fisher-exact test
Table 3.23. Measuring spinal function according to ODI
ODI
Grade 1
Grade 2
Overall
n
35
16
51


17
%

68,63

31,37

100

Table 3.12. JOA measurement at last visit.
Table 3.24. Slippage degree on conventional oblique X-ray
Slippage degree
Numbers (n)
Rate (%)
None
25
49,02

Grade I
24
47,06
Grade II
2
3,92
Overall
51
100
Table 3.25. Screws accuracy measurement by Lonstein
Number
Rate
Criteria
(n)
(%)
Screws to the upper pedicle edge and to the
4
1,96
upper edge of the body
Screws down the lower edge of pedicle
2
0,98
Screws to the pedicle but off the body
3
1,47
Screws to more than 2 times of body edge
3
1,47
on oblique X-ray
Standard screws

192
94,12
Overall
204
100
Table 3.26. Bone grafts location far after surgery.
Graft location
Number (n)
Rate (%)
Good
48
94,12
Average
3
5,88
Overall
51
100
Table 3.29. Overall outcome at last visit
Postoperative results
Number (n)
Rate (%)
Good
36
70,59
Relatively good
15
29,41
Overall
51

100
CHAPTER 4: DISCUSSION
4.2. Sliding position of the vertebrae
Our research shows that the rate of spondylolisthesis L4L5 and L5S1
accounts for 56.9% and 43.1% respectively. Thus, it can be seen that the rate
of sliding of L4L5 floors is more dominant than the other floors. This is
because the L5 vertebra has a strong transverse process, which is the


18
attachment point of many ligaments of the pelvis and the muscles that make
up its close connection with the sacrum, while the L4 vertebra has smaller
and weaker transverse process, less ligaments come to strengthen.
Furthermore, the lumbar spine in the L4L5 region has a greater range of
motion and impact force than L5S1. Therefore, the risk of sliding layer
L4L5 is greater than L5S1.
4.3. Duration of disease progression and medical
treatment before surgery
We have found that in studies patients often arrive late when their
symptoms have manifested. Specifically, in our study the number of
hospitalized cases the most when the disease progressed 1-3 years
accounted for 39.22%; especially, up to 25.49% of cases are hospitalized
when the disease progression is more than 03 years; number of
hospitalized cases in the first year of the disease accounted for 35.29%
(of which 11.76% cases were hospitalized in the first 3 months of the
disease). Thus, the majority of cases hospitalized after at least one year
when the disease onset accounted for the majority with the rate of
64.71%. However, among them, the rate of receiving basic medical
treatment with the right specialty at the hospital only accounts for
47.06%, less than 50% of the total cases in the study; The remainder

accounted for 52.94% of cases or medical treatment but inadequate
according to the procedure, or voluntarily buy drugs to treat symptoms
or go to non-specialist medical examination and treatment
establishments. The above results show that there is still a lack of
understanding in the community, combined with subjective psychology
about one's own health, leading to poor attitudes and awareness in
medical examination and treatment. This affects the progression of the
disease as well as the outcome of surgery and the longer recovery time.
4.4. Clinical symptoms
4.4.1. Mechanical symptoms
The characteristic clinical manifestation of SPL is the combination of
spinal syndrome and nerve root compression syndrome creating lumbar
syndrome with the degree of manifestation depending on the cause, duration
of disease progression, degree of slip and degree of nerve root compression
in each specific patient.
Considering the results of our research shows that: 98.04% of cases
have back pain; 58.82% limited movement in the lumbar region; 92.15%
of the nerve root pain, of which, the pains on one side accounted for
54.90%; In case of interval pain at less than 100m, the majority of them
are 52.94%; 15.7% pain at a distance of 100 - 500m and 1.9% pain at a
distance of more than 500m. Thus, the average pain threshold in the
studies is in the high even at intolerable levels. This reflects the actual


19
situation of the patient coming to the hospital when the illness was
blurred, the back pain and leg pain were severe.
4.4.2. Clinical symptoms
Ladder sign is a typical deformation with high value in the clinical
diagnosis of SPL. Our study met 50.98% of all cases. Next, symptoms of

spastic spasticity due to pain accounted for 74.51%. This result is
appropriate when considering in the study the number of cases of sliding
degree II or more accounts for 68.63% and this rate on X-ray is up to
84.31%. This proves that there is a relatively clear displacement of the
vertebral body sliding compared with the adjacent lower vertebral body.
Therefore, the unstable state of the lumbar spine at the slide is quite clear
leading to the above symptoms are relatively typical and common in the
study. On the other hand, the signs of root stimulation (Lasègue sign) in
our study accounted for 98.04%, of which cases with severe
manifestations (lasègue <30) accounted for 21.57%. . The reason, the
rate of encountering signs of root stimulation in our study is very
popular (up to 98.04%) is due to the rate: stenosis of the spinal canal
accounts for 100%, of which moderate and severe stenosis is 58.82%;
rates of intervertebral foramina stenosis and articular hypertrophy
accounted for 74.51% and 64.71%, respectively. These are the main
causes of compression of nerve roots in SPL. Motion disorder is a
symptom that appears later than sensory disorder but is the main cause
that causes patients to go to the hospital for examination and treatment.
Our study evaluated the patient's movement disorder by the motor scale
of the American Orthopedic Association, the results obtained were only
05 cases with mild muscle weakness, accounting for 9.8%.
To assess the effect on motor function of the lumbar spine, we use the
Oswestry assessment. The results obtained are 39 cases of loss of
function much with ODI index in the range of 41-60%, accounting for
76.47%; 11 cases of loss of function a lot with ODI index from 61% to
80%, accounting for 21.57%. Thus, the number of cases that greatly
affected the motor function of the spine before surgery (from grade III or
higher) accounted for the majority in the study with the rate of 98.04%.
The influence on motor function of the spine is influenced by many
factors, including the main factors that play a decisive role such as the

rate of special back pain when moving, the degree of spasticity, the
degree of nerve root compression, duration of disease progression,
interval pain, and baseline therapy were used.
4.5. Diagnostic imaging before surgery
4.5.1. Conventional X-ray and dynamic X-ray
Conventional X-ray and X-ray are valuable diagnostic imaging methods
in assessing and determining the instability of the lumbar spine in SPL.


20
Considering in our study, the results obtained when the resolution of SPL
according to Meyerding on X-ray conventional inclination has the rate of
SPL at degree I met 16 cases, accounting for 31.37%; Level II SPL has 28
cases, accounting for 54.9%; Level III SPL has 07 cases, accounting for
13.73%. On the other hand, when evaluating the slip on X-ray, we found
that the ratio between the elevation of SPL has changed and especially has
appeared sliding grade IV. Specifically, grade I has 8 cases, accounting for
15.69%; grade II has 23 cases, accounting for 45.1%; grade III has 15 cases,
accounting for 29.41% and grade IV has 05 cases, accounting for 9.8%.
Thus, there has been an increase in slip on X-ray film in the study of each
slip. In which, grade I has 8/16 cases of increasing slip, accounting for 50%;
grade II has 13/28 cases, accounting for 46.43%; grade III has 5/7 cases,
accounting for 71.43%. Considering on the criteria for evaluating the
stability of the spine at the slide through the displacement of the combustion
body slipping forward or the rotation angle at the SPL stratum according to
White A.A. and panjani M.M. we obtained 100% of cases with
displacement above 4.5mm or rotation angle> 25⁰.
4.5.2. Magnetic resonance imaging
The results of our research when examining the criteria on the
obtained MRI scans showed that: The rate of cases with

spondylolisthesis of the spondylolisthesis disc accounted for 94.12%. In
which, the rate of degeneration from grade III or higher accounts for
95.84%. This is due to the fact that in the SPL level, disc damage is very
common due to the abnormal movement of the upper vertebral body.
Especially in spondylolysis SPL with a high risk of instability because of
the loss of connection between the two bodies through the joint block,
resulting in increased pressure to load on the disc and ligament system
every time the spinal segment moves. This results in damage to the disc
fibrous loops and the surrounding ligaments, causing the disc to
degenerate very early. On the other hand, the degeneration of the
spondylolisthesis disc and the adjacent intervertebral disc will increase
the instability in the SPL due to spondylolysis leading to the process of
proliferation of the connective tissue (fiber tissue) at the enclosed pars
with increasing enlargement of the mass of the joints and ligamentum
flavum in order to counteract the anterior slippage of the vertebrae.
However, it is this phenomenon, or in association with disc herniation,
that causes the stenosis of the spinal canal and the loss of intervertebral
foramina. In our study, the rate of spinal stenosis and intervertebral
foramina stenosis due to the above reasons at site of SPL position
accounts for 100% and 74.51% respectively.
4.6. Surgical results
4.6.2. Clinical


21
For postoperative functional muscle symptoms group at the time of
discharge in the study, we found that 100% of cases still had back pain
and 35.29% of cases still limited lumbar spine movement. Thus,
compared to before surgery at the time of discharge from hospital, the
rate of back pain increased by 2% (100% - 98.04%) but the rate of

limited lumbar spine movement has decreased by 23.53% (35.29 % 58.82%). This result showed no proportional change between the two
symptoms. However, when considered at the time of the last visit (≥ 12
months), we have obtained the results of cases that still have lower back
pain than before but still account for a high rate with 82.35%; cases with
limited lumbar spine movement have decreased significantly compared
to the time before surgery and accounted for a low rate with 11.76%.
Thus, it can be found that this lumbar spinal pain symptom does not
affect spinal motor functions much in the study. That proves that the
lumbar spine pain due to instability has been relatively completely
overcome. On the other hand, at the time of discharge, the number of pain
relief only accounted for a small percentage (1.96%), proving that the results
of spinal tube decompression effectively overcome almost completely the
stenosis of the spinal cord due to SPL. This result was confirmed when at
the time of the last examination, there were no cases of intermittent pain and
bilateral root pain. However, this has not really decreased significantly
compared to before surgery, although it has been much reduced compared to
the time of discharge when there are still 35.29% of unilateral spread pain.
The reason, according to us, comes from the fact that when operating the
cases in the study evaluating that: the condition of the fusion stenosis due to
the articular hypertrophy and especially the proliferation of fibrosis in the
pars fissure and intervertebral foramina in response to spondylolisthesis is
common. Therefore, it makes it difficult for the process of decompression of
the intervertebral foramina to release the pinched nerve roots, leading to
unfavorable results. Therefore, the improvement of nerve root stimulation
signs after surgery at the time of discharge (Lasegue sign) in our study is not
really clear (accounting for 10%). This is an effective reflection on the
decompression of pinched nerve roots in surgery. However, this ratio
changed significantly at the last postoperative visit (≥ 12 months) when only
15.69% of cases showed signs of root stimulation with a positive lasegue
test at> 70⁰. This result shows that the postoperative initial root stimulation

is a consequence of the post-decompression nerve root edema by the
processes of eliminating fibrosis, osteoblasts, conjunctival adhesion and
manipulation and slip correction. At the same time, also demonstrated high
efficiency in enlarged intervertebral foramina decompression when followup and assessment for a long enough time, contributing to confirm the
effectiveness of PLIF surgery for spondylolysis SPL. In particular, there was


22
a complete recovery in mobility of 9.8% of cases with preoperative
paralysis, when the final postoperative results were obtained, there were no
cases of motor deficiency.
4.6.3. Evaluate spinal motor function on the Owestry scale
The degree of limited lumbar spinal motor function after surgery at
the time in the study is evaluated to have progressed significantly
compared to before surgery on the Owestry scale (ODI). In which, at the
time of discharge, most of cases have ODI index at grade II accounting
for 72% and grade III at 22%; In particular, there appeared to be 06% of
cases with ODI index at grade I and no cases at grade IV, V. However,
when considered at the last visit (≥ 12 months after surgery 100% of
cases in the study achieved spinal motor function at grade I and II, and
none of the cases were at grade III or higher. In which, grade I accounted
for the majority with the rate of 68.63%; grade II accounts for 31.37%.
4.6.2.2. Result of manipulation, screw and grafts position.
When evaluating surgical results based on the criteria: slippage,
screw position and bone graft, bone reproduce at the time of discharge
and at the last visit (≥ 12 months after surgery) we obtained positive
results on conventional X-rays. Specifically:
Evaluate the screw position.
Out of a total of 204 screws attached to the vertebrae through the
pedicle under the guidance of C - arm in the study evaluated according

to Lonstein's standards, we obtained the result that the number of screws
with the correct standard accounted for 94.12%; the number of screws
that do not meet the standards include 04 screws attached to the upper
pedicle margin and close to the vertebral body(accounting for 1.96%),
02 screws screwed to the lower pedicle margin (accounting for 0.98%),
03 screws beyond the anterior body margin on oblique film (accounting
for 1.47%). However, we found that the cases that under Lonstein
standard do not affect the rectifying and fixing results in practice. This is
evidenced by the assessment results at the time of the last visit, the
standard screw fixing rate did not change and still maintain the fixed
rectification result compared to the time of discharge.
Slippage measurements.
After surgery at the time of discharge, rectification results compared
to before surgery were effective. Of which: 49% of cases in the study
have none spondylolisthesis; 47.1% of cases of sliding grade I and 3.9%
of cases of sliding grade II. There are no cases of SPL from grade III or
higher. This result was maintained steadily during follow-up and at the
last visit (≥ 12 months after surgery) the ratio of slippage compared to
discharge remained unchanged and there was no case of increased
slippage. Thus, this result proves that the fixation and correction of


23
spinal deformities depend a lot on the technical skill, experience of the
surgeon and the degree of spondylolisthesis of the patient. Good
correction to completely no slippage will increase the bone grafting area,
helping the bone to progress smoothly, thereby bringing good outcomes.
Artificial graft location.
The position of the graft also did not change between the time of
immediately after surgery and at the last visit (≥ 12 months after surgery).

Specifically, at the two times above, the accuracy of the artificial graft has a
high rate of good position accounting for 94.12% and only 5.88% of the
cases have the graft in the middle position, no case in the bad position. In
particular, there is no case where the artificial graft is loose and moved
backwards and inserted into the spinal canal, intervertebral foramina or
moved into the vertebral body. This difference in results could be explained
by the better improvement in surgical methods. The reason is because recent
studies in the world have also demonstrated the superiority of the PLIF
method in rectification and immobilization, especially to facilitate the
process of interbody fusing and solidly formation of new bones.
Postoperative bone healing density
Derived from the results of manipulation to achieve the maximum
required on restoring anatomical structure of the sliding spine to
facilitate the bone welding process. Therefore, the majority of cases in
the study have good results after surgery, accounting for 70.6%; A small
number of bone healing cases are relatively good at rate of 29.4% and
absolutely no cases of moderate or no healing according to Bridwell's
standards.
4.6.4. General results after surgery
Regarding the evaluation of general results after surgery, most
patients achieved good results after surgery, some patients achieved
good results, no patients achieved average or bad results.
4.6.4.1. Improve functional symptoms 12 months after surgery
There was a clear improvement in the patient's pain symptoms 12
months before and 12 months after surgery. The difference was
statistically significant between the rate of lumbar spine pain before
surgery and at far postoperative time. Evidence of the difference in
functional symptoms shows that after surgery, the patient almost has
significantly reduced clinical manifestations, demonstrating the success
of surgery.

4.6.4.2. Improve physical symptoms 12 months after surgery
Root stimulation or Laségue positive signs decreased from 98.04%
before surgery to 15.69% at far postoperative time. The difference is
statistically significant with p <0.05. The above improved evidence
shows that: after the surgery of real estate, physical symptoms in the


24
patient have a significant recovery. In some cases of prolonged nerve
root compression or nerve damage before surgery or complications
during surgery, it is necessary to have time to restore function closely
combined with medical treatment to improve the condition.
CONCLUSION
Through the research results on 51 cases of single-stage lumbar
spondylolisthesis due to spondylolysis surgery, decompression,
manipulation, interbody fusion, spinal fusion through pedicle with
screws at the Department of Spinal Surgery We have the following
conclusions at Viet Duc Friendship Institute:
1. Clinical characteristics, imaging diagnosis
Clinical features
- The main clinical manifestation is lumbar syndrome with lumbar
spine pain, accounting for 98.04% with average pain level on the VAS
scale of 6.1 ± 0.9; in which cause limited movement of the lumbar
region and spastic spinal muscles accounting for 58.82% and 74.51%
respectively; Ladder signs are very significant in diagnosis but only met
50.98%. Nerve root pain accounted for 92.15% with a VAS level of 5.6
± 1.3 points and lasègue positive sign with 98.04%; however, it is only at
the level of sensory disorder with the rate of 98.04% and lack of
movement only accounts for 9.8%.
Diagnostic Imaging

- Diagnosis is determined based on conventional X-ray with 54.9%
of grade II spondylolisthesis cases; 31.37% grade I slide and 13.73%
grade III slide. X-ray is valuable in determining the increase in
instability of the spine with the appearance of grade IV slip with the rate
of 9.8% and sliding grade III increase, accounting for 29.41%. In which,
slippage grade I decreased to 15.69% and grade II accounted for
45.10%. Magnetic resonance imaging is very valuable in diagnosing
degenerative and compressive lesions with sliding and adjacent
spondylolisthesis disc degeneration accounting for 94.12% and 76.47%
respectively; articular hypertrophy accounts for 64.71%; intervertebral
foramina stenosis accounts for 74.51% of the cases studied. However,
magnetic resonance only detected 78.43% of the 51 cases of SPL due to
spondylolysis in the study.
2. Surgical results
- Removal of posterior arch surgery and remove the disc for
decompression, manipulation, bone fusion, spinal fixation with a screw
brace through pedicle (PLIF) for single-stage lumbar SPL due to the pars
defects has brought positive results. with average surgical time of 105.5
± 20.9 minutes. The results of manipulation and fixation achieved high


25
efficiency and remained stable throughout the follow-up period, there
was no increase in slippage between the last two visits and at discharge
with 49.02% ; 47.06% of sliding grade I and 3.92% of sliding grade II;
good position bone grafts accounted for 94.12%. Osteoporosis after
surgery at the last visit achieved high results with 100% good and
relatively good bone healing rate, no cases of delayed bone healing or
joint prosthesis. Therefore, clinical improvement was markedly
improved immediately after surgery and progressed well throughout the

follow-up period and is shown by the ODI scale, lumbar spinal pain
symptom and postoperative Lasègue signs decreased compared to with
preoperative statistically significant with p <0.05. The overall results
after surgery at the last visit were very positive with 36 cases with good
results, accounting for 70.6%; 15 cases with relatively good results
accounted for 29.4% and there was no case with average result or less.