Summary of Medical thesis: Morphological characteristics of multilevel thoracic and lumbar vertebral fracture and the effectiveness of surgical treatment.

Describing the morphological characteristic of multilevel thoracic and lumbar vertebral fractures in which surgical treatments are indicated at Da Nang Hospital; evaluating the outcome of surgical treatment for multilevel thoracic and lumbar vertebral fractures at Da Nang Hospital.

Multilevel noncontiguous spinal fractures (MNSF) are defined as fractures of the vertebral column at more than one level According to many reports, multilevel noncontiguous spinal fractures are found at from 3.2% to 16.7% Multilevel spine injuries are often uncommon, occur commonly as a result of high-speed road traffic accidents or falls from a height Multilevel spine injuries tend to be more severe than unilevel because of the other injuries combined Rapid diagnosis   of   MNSF   is   essential   since   a   misdiagnosis   or   delayed diagnosis may complicate the clinical picture.  Therefore, the role

of a thorough physical and radiological examination is the key

to not to miss any lesions Although there are many studies evaluating and treating single level spine fractures, there have not been many reports of multilevel spine injuries In Vietnam, there are not many researches on this issue So we work for:

“Morphological   characteristics   of  multilevel  thoracic  and lumbar   vertebral   fracture  and  the  effectiveness  of  surgical treatment” with these targets:

1 Describing the morphological characteristic of multilevel thoracic and lumbar vertebral fractures in which surgical treatments are indicated at Da Nang Hospital.

2 Evaluating the outcome of surgical treatment for multilevel thoracic and lumbar vertebral fractures at Da Nang Hospital.

New main scientific contributions of the thesis:

­ The research subjects are lesions in multilevel thoracic and lumbar vertebral fractures

­ Providing the evidence of the effectiveness of surgical treatment for multilevel thoracic and lumbar vertebral fractures

- Structure of the thesis: the thesis includes 127 pages with 40 tables, 27 pictures and 10 charts Introduction (2 pages); Chapter 1: Overview (31 pages); Chapter 2: Subjects and Methods of the study (26 pages); Chapter 3: The results of the study (31 pages); Chapter 4: Discussion (33 pages); Conclusion (2 pages); Petition (1 page); List of published articles related to the results of the thesis (1 page); References (138 documents including 33 documents in Vietnamese, 105 documents

in English); The appendices.

SECTION 1 OVERVIEW 1.1 A brief history of treatment of spine fractures.

1.1.1 In the world

Multilevel spine injuries have been reported for a long time Griffith H.B., Gleave J R W, Taylor R G (1966) reported 5 patients accounting for 3.2% of 155 cases of thoracic and lumbar spine fractures Lizbeth C A M G et al (2018) reported 47 cases of multilevel spinal surgery at the Center Dr Manuel Dufoo Olvera in Mexico Thus, the multilevel spine fractures have been studied for a long time, but they are still separated There are no single reports on multilevel spinal

1.1.2 In Vietnam

Previous studies inside the country have only studied level fractures, there were some authors who mentioned several cases of multilevel spinal injuries And there are no separate studies on multilevel thoracic and lumbar spinal injuries

one-1.2 Classification of multilevel thoracic and lumbar veterbral fractures

1.2.1 Classification of Denis

In 1983, Denis introduced the definition of "three-column spine": the anterior, middle and posterior column; and it has been widely applied

1.2.2 Classification of Margel (AO)

In 1994, Margel proposed a classification according to AO (Arbeitsgemeinschaft fur Osteosynthesefragen) which mainly assess spinal morphological damage

1.2.3 Load Sharing Classification (LSC)

In 1994, Mc Cormack and colleagues released a new classification to assess vertebrae damage based on three criteria: the amount of damaged vertebral body, the spread of the fragments in the fracture site, the amount of corrected traumatic kyphosis

1.2.4 Classification of multilevel thoracic and lumbar spinal injury based on the severity of lesion.

In 2005 Vaccaro A.R et al proposed a Thoracolumbar Injury Classification and Severity Score (TLICS) which is is based on three major categories, known as parameters: injury

morphology, posterior ligamentous complex integrity, patient neurology

- To measure local Kyphotic Angle (LKA) and Cobb Angle

1.4.2. Computed Tomography Scan.

Computed tomography (CT-scan) provides greater details and resolution for evaluation of the bone elements and assessment of the entire spinal canal

CT-scan allows us to assess bone lesions, fracture lines, fracture fragments, lesions of processes, joints, holes, posterior arcs, damaged fragments moving into the spinal canal, and spinal stenosis

1.5 Methods of Spine Stabilization.

1.5.2 Posterior Stabilization Systems

Posterior stabilization systems can restore vertebral body height 

by   distraction   forces   Furthermore,   anterior   and   middle   columns maintained   their   normal   length   during   correction   of   kyphosis. Distractive   forces   provided   by   the   posterior   stabilization   system developed a tensile strength in the posterior longitudinal ligament which pushes back the retro­pulsed bone fragments forward. This process   has   been   termed   ligamentotaxis   and   it   is   beneficial 

1.5.2.3 Posterior lumbar interbody fusion surgery (PLIFs).

Transpedicular screw is now the standard of spine fusion surgery for many spinal diseases We use a "free hand" technique with screws are parallel to the joint of the vertebra and we use X-rays for guiding during surgery

1.6 Indications of surgical treatment for multilevel thoracic and lumbar fractures

Greenberg M.S (2010) refers to a treatment indication based on a clear, complete description of the morphological characteristics of lesions in three columns, signs of neurological damages and their associations They also consider the characteristics of the fracture group as well as the location of fractures in assessing the instability of the injury In this document, author McAfee presents the specified surgery

in the case

1.7 Evaluation the results of surgical treatment

1.7.1 The assessment of the results of spinal correction and stabilization surgery

Anteroposterior  (AP) and oblique X-rays on all patients; measuring local LKA and Cobb Angle on oblique X-rays is the most commonly used method today

1.7.2 The assessment of the neurological recovery after surgery

Based on the neurological damage classification table according to Frankel: Pre-operative evaluation, post-operative evaluation, and evaluations in follow-up visits, monitoring changes in Frankel level between two consecutive visits

CHAPTER 2 SUBJECTS AND METHODS OF STUDY

2.1 Subjects

2.1.1.The criteria for selecting research patients

- All patients diagnosed with multilevel vetebral fractures (≥ 2 levels) from the fourth thoracic vertebra to the fifth lumbar vertebra, having unstable fracture, and caused by trauma These include multilevel vertebral fractures emphasized on thoracic-thoracic, thoracic-lumbar, and lumbar-lumbar segments

-All patients who have plain and oblique X-rays, computerized tomography scan and posterior stabilization of

at least one fractured vertebra body

2.1.2 Exclusion criteria

-Elderly patients with osteoporosis, bone tumors, tuberculosis, cardiovascular disease, coagulopathy, etc Patients with brain sequelae or brain entity pathologies, spinal cord sequelae or paralysis of peripheral nerves in the lower extremities due to pathology, mental disorders that distort nerve assessment at the spinal cord.  Patients who had surgery then lost information, did not come back for examination, or did not cooperate with treatment

2.2 Research method

2.2.1 Sample size

Convenience sampling method, including all patients who match selection and exclusion criteria during the research period

2.2.2 Method of data collection

Clinical and radiological findings : routine X-ray, CT-scan; the results of treatment are collected based on a pre-set form Direct clinical examination, assessment of symptoms, analysis

of results of X-rays, CT scans before surgery

Perform posterior stabilization surgery, evaluate the postoperative results All patients receive discharge instruction

in self-care and mobilization

Re-examination after 06 months: examination of clinical symptoms such as movement on ASIA scale, sensation, reflexes, urination, incisions, neurological recovery according

to Frankel level, urinary tract infections, pneumonia, muscle atrophy, regular X-ray measuring KLA, height of fractured vertebra, screw position

2.3 Method of Data Analysis

Collected data were processed in the statistical software 12.2.1.0

3.1. Clinical and radiological characteristics of multilevel thoracic and lumbar vertebral fractures

3.1.1 General characteristics

3.1.1.1 Age, gender, occupation

Age group 20-19 accounted for the majority of cases with

19 patients (35.84%) The youngest age 16, the oldest age Average age was 37.47 ±13.47 Male/Female ratio: 4.88/1.Workers accounted for the higest rate with 26 cases (49.05%) The majority were workers and freelancers with

36 cases, accounting for 67.85%

3.1.2 Clinical conditions of patients on admission

3.1.2.6 The degree of nerve damage according to Frankel

Table 3.5 Patient classification according to Frankel

neurological damageFrankel No Patients (n) Percentage (%)

p < 0.01

3.1.2.7 The associated injuries

Table 3.6 The associated injuries

Associated

lesions

No Patients (n)

Percentag

e (%)

p < 0.01

3.1.3.1 Detect vertebral lesions on regular X-ray and CT-scan

In 53 cases of MNSF, CT-scans revealed 118 fractured vertebrae The number of cases with 2 broken vertebrae accounted for the highest proportion with 44 patients (83.01%), and with 4 fractures or 5 fractured vertebrae was 1 patient accounted for 1.88%

3.1.3.2 Distribution of multilevel vertebral fractures

Chart 3.7 Distribution of multilevel vertebral fractures

3.1.3.4 Detecting contiguous or noncontiguous lesions on scans

CT-Chart 3.8 Detecting contiguous or noncontiguous lesions on

CT-scans

3.1.3.6 The fragment of bone causing spinal stenosis on scans

CT-Chart 3.9 Spinal stenosis

3.1.9 The correlation between clinical and radiological findings

Table 3.16. The correlation between Denis classification of spinal fractures and The Frankel Grade classification

Total

n, (%)

10(18.86)

2(3.77)

7(13.20)

4 (7.54)

30(56.63) 53 (100)

3.1.10 The correlation between neurological damage and degree of spinal stenosis on CT-scan

Table 3.17 The correlation between degree of spinal stenosis

and degree of paralysis

stenosis <

50%

21 (39.63)Spinal

stenosis ≥

50%

24 (45.28)Total

n, (%)

10(18.86

)

2(3.77)

7(13.20)

4(7.54)

30(56.63)

53 (100)

3.2.1.6 Overlapping surgeries

Table 3.23 Overlapping surgeries

Overlapping surgeries Patients No

%)

7 (13.2 0%)

4 (7.54

%)

30 (56.6 3%)

53 (100%)

4 (7.54%

)

4 (7.54%

)

34 (64.18%

)

53 (100%)

3.2.2.4 The result of local kyphosis angle recovery results

Table 3.28 Local kyphosis angle recovery results

Post-operation 10 27 0 10.56 ± 5.530 (2)

Re-examination 20 29 0 13.37 ± 5.940 (3)

3.2.2.5. The results of vertebral body compression recovery after  surgery 

Table 3.30 Anterior Vertebral Body Compression Percentage

Results

Index operation (1) Pre- surgery

Post-(2)

examination (3)

Re-Compare (p)

24.92 ± 16.03 (0.08- 67.02)

25.30 ± 16.03 (1.59- 76.31)

p12= 0.0001 p13= 0.0001 p23= 0.9031

CHAPTER 4 DISCUSSION

4.1 Clinical and radiological characteristics of multilevel thoracic and lumbar vertebral fractures

The rate of paralysis varies by author, depending on research subjects

4.1.2.7 Associated injuries

Patients with multilevel spinal injuries were mostly caused

by a complex, strong traumatic mechanism, which often resulted in other traumas Patients with other accompanied injuries accounted for the highest proportion with 36 cases (67.93%), in which multiple injuries ( 2 types of combined injuries or more) had 11 patients (20.78%)

Our research had a high percentage of combined injuries due to the strong traumatic mechanism of multilevel spinal injuries that caused damage to organs of the body

4.1.3 Radiological findings

4.1.3.1 Detection of vertebral lesions on regular X-ray and CT-scan

In all cases where only one fractured vertebra was detected

on X-rays, more than one fracture was detected on CT-scans CT-scans revealed 118 fractures in 53 cases (ratio: 2.22 fractures/1 patient)

Reasons for missing lesions on X-ray films: poor image quality, not capturing the entire spine at our request, initial examinations by inexperienced physicians

This shows that lesions will be more accurately detected in CT-scanned patients than in patients with x-rays only This is considered the best method for assessing lesions of bone today

4.1.3.2 Distribution of lesions of multilevel spinal fractures.

Figure 3.7 shows that the most common segment among all patients suffering multilevel spinal fractures were concentrated

in thoracic+thoracic segment with 11 cases (20.76%), thoracic+lumbar segment and lumbar+ lumbar segment with

21 cases (39.62%)

Most injuries emphasized on the thoracic+lumbar segment and lumbar+ lumbar segment because these segments are mobile vertebrae that are prone to injury And the thoracic segment has protection of the ribs and back muscles so it is less vulnerable

We found that the lesions in two separate sections of lumbar and thoracic spine accounted for a relatively high proportion (39.62%) Therefore, we recommend that in case of

multiple injuries, it is essential to have a careful examination and X-ray of the entire spine to avoid missing multilevel noncontiguous spinal fractures to prevent complications from errors of omission.

4.1.3.4 Detection of contiguous or noncontiguous fractures on CT-scan

Figure 3.8 showed that there were 36 patients with contiguous fractures, accounting for a high rate of 67.93% and

17 patients with non-contiguous fractures (32.07%)

The rate of fracture detection in our study is relatively high compared to other previous reports, probably because our hospital is a general hospital, not a specialty hospital We not only treat spinal injuries but also treat other injuries such as thoracic, abdominal, or extremity fractures; and more importantly, our hospital has intensive unit care which is essential for treatment of patients with severe injuries Therefore, most of traumatic cases were admitted to our hospital

4.1.3.6 The fragment of bone causing spinal stenosis on scan

CT-Figure 3.9 shows that fragments of bones causing spinal stenosis> 50% were 21 patients, accounting for 39.63% Bone fragments causing spinal stenosis ≥ 50% were 24 patients, accounting for 45.28% This suggests that the majority of patients with multilevel spinal injuries due to a strong, complex trauma often have severe spinal stenosis

4.1.9 The correlation between clinical and radiological findings.