Purpose: To evaluate the relationship between lumbosacral discopathy status and paraspinal atrophic changes (Cross-sectional area (CSA) and fatty infiltration (FI)) among different age groups. Materials and Methods: We retrospectively evaluated 200 patients with confirmed discopathy who were examined by lumbosacral Magnetic Resonance Imaging (MRI) at the two main governmental hospitals in Gaza Strip. Using ImageJ software and quantification threshold technique, we measured the CSA and FI of paraspinal muscles {multifidus (MF) & erector spinae (ES)}. The interpretation of MRI images was performed by two radiologists with a good inter-observer agreement between the radiological discopathy findings. Results: The highest percentage and severity of discopathy were noticed at the level of L4/5 (89.5%), followed by L5/S1 (14.5%). The FI is increased towards lower levels of L3/4 to L5/S1. No correlation was found between discopathy level, the severity of discopathy, and CSA of MF & ES muscles. In contrast, a correlation was observed between FI of MF & ES muscles, discopathy level, and severity. Also, the results illustrated no significant relation was observed between CSA of MF & ES muscles and age groups (P > 0.05), while a significant correlation was reported between FI and age groups (P < 0.05). Conclusion: The MRI quantification threshold pixel technique for paraspinal muscles reflected the atrophic changes like CSA and FI in discopathy patients.
Magnetic resonance imaging (MRI) is an excellent noninvasive tool to assess the lumbosacral spine pathology and adjacent muscles changes. The posterior paraspinal muscles (multifidus (MF) & erector spinae (ES) muscles) play an essential role in spinal stability and flexibility, and weakness of those muscles is a major cause of recurrent Low Back Pain (LBP) [
This analytical cross-sectional retrospective study included 200 discopathy patients (95 female and 105 male) with non-probability consecutive sampling, which selected the MRI departments at two main governmental hospitals in Gaza Strip; Al-Shifa Medical Complex and European Gaza Hospital (EGH). The inclusion criteria were patients aged 18 - 80 years and with a confirmed discopathy diagnosis. Patients with lumbosacral spine congenital anomalies, fractures, infections, vertebral metastasis, and pregnancy were excluded to avoid bias due to CSA & FI changes.
The timeframe for this study was from April 2020 to April 2021. The study was conducted after getting ethical and administrative approval from Al-Azhar Gaza-University, Helsinki committee, ministry of health, and human resources development administration, respectively.
MRI scans were conducted with a 1.5-Tesla MR device using a spine coil (Philips Intera; Siemens-MAGNETOM) with patients in the neutral supine position. A routine assessment was carried out with T2-weighted turbo spin-echo (TSE) sagittal, T1-weighted TSE sagittal, and T2-weighted TSE axial images. T2-weighted TSE. Imaging parameters for scan were: TR: 3650 ms; TE: 120 ms; slice thickness = 3 mm; NAS or Average = 4. Axial slices were performed parallel to L3/4, L4/5, and L5/S1 intervertebral disc space without overlapping the slice boxes. Also, were used for muscle area measurements and to determine the degree of FI.
Quantitative measurements and yields for the MF & ES muscles were taken by ImageJ software (version 1.52 National Institutes of Health). The process was picked up by one of the investigators, who expert in ImageJ quantitative thresholding pixel filter analysis. The expert investigator manually drew the border of the MF & ES muscles at L3/4, L4/5L, and L5/S1 on the six axial slices with coverage of the upper and lower disc recess using ImageJ software. The mean of FI SI among each slice was calculated based on higher SI equated to more fat inside the ROI. CSA measurements of the MF & ES muscles were taken, with the area measurement in (cm2) by margins of each muscle to be measured within the ROI to exclude the fatty areas in the periphery and to ensure the muscles’ size. Besides, FI was assessed by manually adjusting a threshold signal within the total muscle CSA to only include pixels in the muscular adipose tissue area (See
Based on the previous studies [
have reported intra-rater ICCs varying between 0.81 and 0.99 [
Patients fulfilling the aforementioned inclusion criteria were retrospectively evaluated for discopathy by two expert radiologists. The Inter-observer agreement for radiological finding of discopathy was good (kappa = 0.84 [95% confidence interval (CI) 0.73 - 0.95]). Radiological findings were focused on determining the involvement, types, side, location, and severity/size of the intervertebral discopathy. The location and severity/size of the intervertebral discopathy are based on the reference stander guidelines according to Arrotegui (2019) [
Data were analyzed using the Statistical Package of Social Sciences (SPSS) system (Version 25). Descriptive statistics in the form of frequencies and percentages were employed. Also, means and standard deviations were calculated for each muscle of interest. KAPPA agreement was used to determine the agreement between two radiologists in MRI radiological findings. Spearman correlation analysis and one-way ANOVA tests were applied. The confidence intervals (CI) were reported as 95%, and a P-value of less than 0.05 was considered statistically significant.
The mean age in our study was 45.7 ± (13.6), with 74 patients (37%) in themiddle age group (41 - 55 y), 73 patients (36.5%) in the young age (18 - 40 y), and 53 patients (26.5%) patients in the old age group (56 - 80). Most of the participants were male, [105 (52.5%) vs 95 female (47.5%), and the highest percentage of Body mass index (BMI) categories was in the obese category, 84 (42%). Most
| Variables | No. of Patients (n = 200) | |
|---|---|---|
| 45.7 ± (13.6) | Age Mean ± (SD) | |
| Age groups | ||
| 73 (36.5%) | Young age (18 - 40 y) | |
| 74 (37%) | Middle age (41 - 55 y) | |
| 53(26.5%) | Old age (56 - 80 y) | |
| Gender | ||
| 105 (52.5%) | Male | |
| 95 (47.5%) | Female | |
| Body mass index | ||
| 59 (29.5%) | Normal weight | |
| 57 (28.5%) | Overweight | |
| 84 (42%) | Obese | |
| 18 (9%) 16 (8%) 166 (83%) | Discopathy complain LBP only Radiated pain only LBP with radiated pain | |
| 18 (9%) 46 (23%) 72 (36%) 64 (32%) | Radiculopathy sides No radical pain Right side Left side Both sides | |
| 26 (13%) 20 (10%) 154 (77%) | LBP classification Acute LBP (Less than 6 weeks) Sub-acute LBP (6 to 12 weeks) Chronic LBP (More than 12 weeks) | |
participants, 105 (52.5%), were suffering from LBP with radiated pain. The radiated pain was mostly on the left side, 72 patients (36%), whereas 46 patients (23%) had radiated pain to the right side. The majority of patients, 154 (77%), had chronic LBP (more than 12 weeks).
The discopathy involvement was predominant at the lower three levels, with the highest percentage (89.5%) at L4/5, followed by L5/S1, (67%), then L3/4 (40.5%). The highest percentage of disc bulge was at L4/5 (70%), followed by L5/S1 (45%) and L3/4, (31.5%). In contrast, the highest percentage of disc herniation was at L5/S1 (9.5%), followed by L4/5 (8.5%) then L3/4 (20.5%). Regarding the affected
| MRI radiological finding by disc level for discopathy | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Discopathy status | L1/2 | L2/3 | L3/4 | L4/5 | L5/S1 | |||||
| (N%) | (N%) | (N%) | (N%) | (N%) | ||||||
| Discopathy involvement | ||||||||||
| Yes | 10 (5%) | 27 (13.5%) | 81 (40.5%) | 179 (89.5%) | 134 (67%) | |||||
| No | 190 (95%) | 173 (86.5%) | 119 (59.5%) | 21 (10.5%) | 66 (33%) | |||||
| Discopathy types | ||||||||||
| No Discopathy | 190 (95%) | 173 (86.5%) | 119 (59.5%) | 21 (10.5%) | 66 (33%) | |||||
| Disc protrusion | 1 (0.5%) | 2 (1%) | 12 (6%) | 10 (5%) | 19 (9.5%) | |||||
| Disc herniation | 2 (1%) | 1 (0.5%) | 5 (20.5%) | 17 (8.5%) | 19 (9.5%) | |||||
| Disc bulge | 4 (2%) | 229 (11%) | 63 (31.5%) | 140 (70%) | 90 (45%) | |||||
| Disc cephalic migration | 1 (0.5%) | 0 (0%) | 1 (0.5%) | 3 (1.5%) | 2 (1%) | |||||
| Disc caudal migration | 2 (1%) | 1 (0.5%) | 0 (0%) | 9 (4.5%) | 3 (1.5%) | |||||
| Disc sequestration | 0 (0%) | 1 (0.5%) | 0 (0%) | 0 (0%) | 1 (0.5%) | |||||
| Discopathy affected side | ||||||||||
| No disc | 190 (95%) | 173 (86.5%) | 119 (59.5%) | 21 (10.5%) | 66 (33%) | |||||
| Right side/Asymmetric | 5 (2.5%) | 5 (2.5%) | 19 (9.5%) | 29 (14.5%) | 30 (15%) | |||||
| Left side/Asymmetric | 1 (0.5%) | 9 (4.5%) | 16 (8%) | 58 (29%) | 39 (19.5%) | |||||
| Both side/diffuse | 1 (0.5%) | 12 (6%) | 35 (17.5%) | 85 (42%) | 39 (19.5%) | |||||
| Central/Focal | 3 (1.5%) | 1 (0.5%) | 7 (3.5%) | 7 (3.5%) | 30 (15%) | |||||
| Discopathy location | ||||||||||
| No disc | 190 (95%) | 173 (86.5%) | 119 (59.5%) | 21 (10.5%) | 66 (33%) | |||||
| central zone | 3 (1.5%) | 1 (0.5%) | 8 (4%) | 10 (9.5%) | 29 (14.5%) | |||||
| Subarticular zone | 3 (1.5%) | 2 (1%) | 5 (2.5%) | 16 (8%) | 18 (9%) | |||||
| Foramina | 0 (0%) | 9 (4.5%) | 35 (17.5%) | 105 (52.5%) | 47 (23.5%) | |||||
| Extra-foramina | 4 (2%) | 15 (7.5%) | 33 (15.5%) | 48 (24%) | 40 (20%) | |||||
| Discopathy size/severity | ||||||||||
| Normal | 190 (95%) | 173 (86.5%) | 119 (59.5%) | 21 (10.5%) | 66 (33%) | |||||
| Grade 1 (Mild) | 4 (2%) | 13 (6.5%) | 39 (19.5%) | 78 (39%) | 67 (33.5%) | |||||
| Grade 2 (Moderate) | 2 (1%) | 9 (4.5%) | 26 (13%) | 72 (36%) | 46 (23%) | |||||
| Grade 3 (Sever) | 4 (2%) | 5 (2.5%) | 16 (8%) | 29 (14.5%) | 21 (10.5%) | |||||
| Quantification yields of discopathy paraspinal muscles | ||||||||||
| Paraspinal muscles | L1/2 | L2/3 | L3/4 | L4/5 | L5/S1 | |||||
| Mean ± (SD) | Mean ± (SD) | Mean ± (SD) | Mean ± (SD) | Mean ± (SD) | ||||||
| Multifidus muscles | ||||||||||
| CSA (cm2) | ||||||||||
| Right Side | 5.67 ± (2.3) | 6.12 ± (1.7) | 8.64 ± (4.13) | 9.06 ± (2.2) | 9.59 ± (3.02) | |||||
| Left Side | 6.09 ± (5.26) | 6.35 ± (1.8) | 7.14 ± (2.08) | 8.69 ± (2.2) | 9.19 ± (2.91) | |||||
| Fatty infiltration ratio (%) | ||||||||||
| Right Side | 47.31 ± (18.1) | 43.94 ± (17.6) | 44.81 ± (16.6) | 48.64 ± (16.4) | 53.90 ± (17.09) | |||||
| Left Side | 48.61 ± (18.8) | 44.79 ± (18.3) | 45.06 ± (17.3) | 48.84 ± (17.2) | 54.48 ± (17.13) | |||||
| Erector spinae muscles | ||||||||||
| CSA (cm2) | ||||||||||
| Right Side | 19.53 ± (4.6) | 19.57 ± (5.1) | 21.14 ± (5.9) | 18.5 ± (13.6) | 14.3 ± (6.89) | |||||
| Left Side | 19.45 ± (4.5) | 19.6 ± (5.3) | 19.8 ± (5.09) | 17.6 ± (4.13) | 13.6 ± (6.69) | |||||
| Fatty infiltration ratio (%) | ||||||||||
| Right Side | 37.97 ± (14.4) | 43.92 ± (17.5) | 44.68 ± (15.9) | 52.13 ± (16.24) | 58.03 ± (17.6) | |||||
| Left Side | 38.43 ± (15.94) | 40.19 ± (16.3) | 44.31 ± (16.19) | 51.83 ± (17.7) | 58.42 ± (19.3) | |||||
side of discopathy, the discopathy at level L3/4 is more compressed on the right side (9.5%) than on the left side (8%). In contrast, the discopathy at level L4/5 is more compressed on the left side (29%) than on the right side (14.5%). Similarly, at level L5/S1, the discopathy is more compressed on the left side (19.5%) than on the right side (15%). On the other hand, At level L3/4, L4/5 and L5/S1 the percentage of the discopathy compression on the foramina versus extra-foramina site as follow: {L3/4: 17.5% vs 15.5%, L4/5: 52.5% vs 24%, L5/S1: 23.5% vs 20%}. At levels L3/4, L4/5, and L5/S1, regarding the percentage of disc size and severity, the highest percentage in grade 1 (mild), followed by grade 2 (moderate), then grade 3 (severe) {L3/4: 19.5%, 13%, 8%; L4/5: 39%, 36%, 14.5%; L5/S1: 33.5%, 23%, 10.5%}. Concerning the quantification yields (CSA & FI) in ES & MF muscles for discopathy participants, the CSA of MF muscles were in a direct proportionate trend from L1/2 to L5/S1 [On the right side: from 5.67 ± (2.3) to 9.59 ± (3.02); On the left side: from 6.09 ± (5.26) to 9.19 ± (2.91)]. Likewise, the FI of MF muscles increased from L1/2 to L5/S1 [On the right side: from 47.31% ± (18.1)% to 53.90% ± (17.09)%; On the left side: from 48.61% ± (18.8)% to 54.48% ± (17.13)%]. Regarding CSA of ES muscles, there is an indirect relationship trend from L1/2 to L5/S1 [On the right side: from 19.53 ± (4.6) to 14.3 ± (6.89); On the left side: from 19.45 ± (4.5) to 13.6 ± (6.69)]. In contrast, the FI of ES muscles increased from L1/2 to L5/S1 [On the right side: from 37.97% ± (14.4)% to 58.03% ± (17.6)%; On the left side: from 38.43% ± (15.94)% to 58.42% ± (19.3)%].
1) At level L3/4:
There was no statistical correlation observed between involvement, types, affect side, location, and severity/size of lumbosacral discopathy with both CSA of
| (cm2) Muscles CSA | Discopathy involve | Discopathy types | Discopathy affect side | Discopathy location | Discopathy size/severity | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| R | p-value | R | p-value | R | p-value | R | p-value | R | p-value | ||
| L3/4 | |||||||||||
| Multifidus | |||||||||||
| Right side | 0.02 | 0.777 | 0.027 | 0.699 | 0.02 | 0.774 | 0.031 | 0.659 | 0.049 | 0.488 | |
| Left side | 0.055 | 0.439 | 0.068 | 0.336 | 0.063 | 0.375 | 0.043 | 0.545 | 0.057 | 0.42 | |
| Erector spinae | |||||||||||
| Right side | 0.037 | 0.6 | 0.003 | 0.97 | 0.012 | 0.868 | 0.057 | 0.422 | 0.01 | 0.891 | |
| Left side | 0.091 | 0.202 | 0.043 | 0.546 | 0.049 | 0.491 | 0.11 | 0.119 | 0.059 | 0.403 | |
| L4/5 | |||||||||||
| Multifidus | |||||||||||
| Right side | 0.068 | 0.338 | 0.103 | 0.147 | 0.137 | 0.052 | 0.174* | 0.014* | 0.037 | 0.603 | |
| Left side | 0.025 | 0.721 | 0.023 | 0.742 | 0.118 | 0.096 | 0.025 | 0.729 | 0.027 | 0.704 | |
| Erector spinae | |||||||||||
| Right side | 0.113 | 0.11 | 0.183* | 0.011* | 0.135 | 0.056 | 0.124 | 0.08 | 0.04 | 0.575 | |
| Left side | 0.095 | 0.181 | 0.124 | 0.081 | 0.098 | 0.167 | 0.077 | 0.28 | 0.037 | 0.604 | |
| L5/S1 | |||||||||||
| Multifidus | |||||||||||
| Right side | 0.009 | 0.899 | 0.043 | 0.549 | 0.009 | 0.905 | 0.013 | 0.859 | 0.036 | 0.61 | |
| Left side | 0.058 | 0.414 | 0.066 | 0.355 | 0.041 | 0.577 | 0.053 | 0.452 | 0.069 | 0.333 | |
| Erector spinae | |||||||||||
| Right side | 0.006 | 0.938 | 0.022 | 0.752 | 0.004 | 0.955 | 0.069 | 0.332 | 0.039 | 0.585 | |
| Left side | 0.014 | 0.844 | 0.001 | 0.996 | 0.022 | 0.754 | 0.094 | 0.185 | 0.046 | 0.521 | |
| (%) Fatty infiltration | Discopathy involve | Discopathy types | Discopathy affect side | Discopathy location | Discopathy size/severity | ||||||
| R | p-value | R | p-value | R | p-value | R | p-value | R | p-value | ||
| L3/4 | |||||||||||
| Multifidus | |||||||||||
| Right side | 0.109 | 0.124 | 0.143* | 0.044* | 0.13 | 0.067 | 0.113 | 0.111 | 0.147* | 0.038* | |
| Left side | 0.129 | 0.068 | 0.135 | 0.057 | 0.158* | 0.026* | 0.123 | 0.083 | 0.173* | 0.014* | |
| Erector spinae | |||||||||||
| Right side | 0.133 | 0.06 | 0.166* | 0.019* | 0.154* | 0.029* | 0.163* | 0.021* | 0.163* | 0.021* | |
| Left side | 0.065 | 0.359 | 0.091 | 0.198 | 0.089 | 0.209 | 0.076 | 0.287 | 0.089 | 0.209 | |
| L4/5 | |||||||||||
| Multifidus | |||||||||||
| Right side | 0.035 | 0.622 | 0.173* | 0.015* | 0.059 | 0.406 | 0.042 | 0.551 | 0.168* | 0.018* | |
| Left side | 0.059 | 0.41 | 0.216* | 0.002* | 0.011 | 0.881 | 0.035 | 0.627 | 0.165* | 0.019* | |
| Erector spinae | |||||||||||
| Right side | 0.113 | 0.11 | 0.054 | 0.45 | 0.264* | 0.001* | 0.121 | 0.088 | 0.152* | 0.032* | |
| Left side | 0.151* | 0.033* | 0.065 | 0.36 | 0.292* | 0.001* | 0.141* | 0.046* | 0.152* | 0.032* | |
| L5/S1 | |||||||||||
| Multifidus muscles | |||||||||||
| Right side | 0.470* | 0.032* | 0.198* | 0.047* | 0.397* | 0.017* | 0.244* | 0.036* | 0.271* | 0.019* | |
| Left side | 0.397* | 0.031* | 0.113* | 0.041* | 0.378* | 0.027* | 0.352* | 0.043* | 0.391* | 0.016* | |
| Erector spinae | |||||||||||
| Right side | 0.068 | 0.336 | 0.007 | 0.919 | 0.103* | 0.041* | 0.004 | 0.958 | 0.214* | 0.048* | |
| Left side | 0.037 | 0.606 | 0.016 | 0.826 | 0.147* | 0.025* | 0.002 | 0.978 | 0.221* | 0.038* | |
*Statistical significant.
MF & ES muscles. Also, a weak positive correlation was noticed between FI and discopathy size/severity, type, and side. The right side of the ES muscles has shown a weak positive correlation between FI and discopathy size/severity (R = 0.163, P-value = 0.021), discopathy types (R = 0.166, P-value = 0.019), discopathy side (R = 0.154, P-value = 0.029), and with discopathy locations (R = 0.163, P-value = 0.021).
2) At level L4/5:
A weak positive correlation was reported on the right side of the ES muscle with discopathy types (R = 0.183, P-value = 0.010), whereas no correlation was seen on the left side. Furthermore, a weak positive correlation was shown on the right side of the MF with discopathy location (R = 0.174, P-value = 0.014), whereas no correlation was obvious on the left side. On the other hand, a weak positive correlation between FI and discopathy size/severity on the right and the left side of the L4/5 MF muscles (R = 0.168, P-value = 0.018, and R = 0.165, P-value = 0.019, respectively). Similarly, a weak positive correlation between FI and discopathy types on the right and left sides (R = 0.173, P-value = 0.015, and R = 0.216, P-value = 0.002, respectively). Furthermore, the right and left sides of the ES muscles were noted to have a weak positive correlation between FI and discopathy size/severity. However, the right and left sides of the ES muscles had a moderate positive correlation between FI and discopathy side.
3) At level L5/S1:
No statistical correlation was reported between involvement, types, affect side, location, and severity/size of lumbosacral discopathy with CSA of both sides of the MF & ES muscles. However, a moderate positive correlation was observed between the right and left MF sides, and FI with discopathy involvement (R = 0.470, P-value = 0.032, and R = 0.397, P-value = 0.031, respectively). While there was a weak positive correlation between the right and left MF side and FI with
| (cm2) Muscles CSA | Young age | Middle age | Old age | F | Overall P-value |
|---|---|---|---|---|---|
| L3/4 | |||||
| Multifidus | |||||
| Right side | 8.67 ± (2.616) | 8.14 ± (2.627) | 9.29 ± (6.732) | 1.209 | 0.301 |
| Left side | 7.76 ± (2.153) | 6.75 ± (1.887) | 6.83 ± (2.074) | 5.314 | Overall P-value = 0.006* |
| Young VS Middle age = 0.009* | |||||
| Young VS Old age = 0.009* | |||||
| Erector spinae | |||||
| Right side | 20.32 ± (5.59) | 21.18 ± (6.002) | 22.22 ± (6.236) | 1.598 | 0.205 |
| Left side | 19.62 ± (4.758) | 19.57 ± (5.157) | 20.41 ± (5.488) | 0.492 | 0.612 |
| L4/5 | |||||
| Multifidus | |||||
| Right side | 9.72 ± (2.183) | 8.72 ± (2.103) | 8.63 ± (2.343) | 5.15 | 0.007 |
| Left side | 9.23 ± (2.191) | 8.41 ± (2.065) | 8.33 ± (2.326) | 3.504 | Over all P-value = 0.032* |
| Young VS Middle age = 0.020* | |||||
| Young VS Old age = 0.020* | |||||
| Erector spinae | |||||
| Right side | 17.53 ± (4.024) | 19.69 ± (21.67) | 18.01 ± (4.978) | 0.496 | 0.609 |
| Left side | 17.8 ± (4.284) | 17.14 ± (3.637) | 17.8 ± (4.605) | 0.584 | 0.558 |
| L5/S1 | |||||
| Multifidus | |||||
| Right side | 10.24 ± (2.751) | 9.06 ± (3.042) | 9.43 ± (3.252) | 2.977 | 0.053 |
| Left side | 9.74 ± (2.82) | 8.77 ± (2.665) | 9.02 ± (3.289) | 2.172 | 0.117 |
| Erector spinae | |||||
| Right side | 14.21 ± (4.311) | 14.5 ± (9.847) | 14.22 ± (4.444) | 0.039 | 0.962 |
| Left side | 13.63 ± (4.556) | 13.67 ± (9.385) | 13.36 ± (4.356) | 0.037 | 0.964 |
discopathy type, a moderate positive correlation was seen between the right and left MF sides and FI with discopathy affected side. A significant association was observed between FI of both sides of the MF muscles with the discopathy severity/size. A weak positive correlation was noticed between FI of the ES on the right and left side and discopathy on the affected side (R = 0.103, P-value = 0.041, and R = 0.147, P-value = 0.025, respectively). Likewise, a weak positive correlation was observed between the right and left side of ES muscles FI with discopathy severity/size. In contrast, no statistical correlation was noticed between FI of ES muscle and involvement, types, and location of lumbosacral discopathy (P-value > 0.05).
| Fatty infiltration (%) | Young age | Middle age | Old age | F | Overall P-value |
|---|---|---|---|---|---|
| L3/4 | |||||
| Multifidus | |||||
| Right side | 36.98 ± (14.16) | 45.11 ± (13.753) | 55.16 ± (17.957) | 22.226 | Over all P-value = 0.001* |
| Young VS Middle age = 0.004* | |||||
| Young VS Old age = 0.001* | |||||
| Middle VS Old age = 0.011* | |||||
| Left side | 36.4 ± (13.482) | 46.14 ± (14.265) | 55.49 ± (20) | 22.885 | Over all P-value = 0.001* |
| Young VS Middle age = 0.001* | |||||
| Young VS Old age = 0.000 | |||||
| Middle VS Old age = 0.03 | |||||
| Erector spinae | |||||
| Right side | 38.23 ± (14.63) | 45.43 ± (15.15) | 52.5 ± (15.297) | 14.044 | Over all P-value = 0.001* |
| Young VS Middle age = 0.012* | |||||
| Young VS Old age = 0.001* | |||||
| Left side | 37.42 ± (13.12) | 44.71 ± (16.075) | 53.25 ± (15.953) | 17.061 | Over all P-value = 0.001* |
| Young VS Middle age = 0.011* | |||||
| Young VS Old age = 0.001* | |||||
| L4/5 | |||||
| Multifidus | |||||
| Right side | 40.88 ± (13.71) | 48.57 ± (13.273) | 59.4 ± (18.026) | 23.958 | Over all P-value = 0.001* |
| Young VS Middle age = 0.006* | |||||
| Young VS Old age = 0.001* | |||||
| Middle VS Old age = 0.001* | |||||
| Left side | 39.98 ± (15.11) | 47.71 ± (15.085) | 58.25 ± (13.613) | 23.478 | Over all P-value = 0.002* |
| Young VS Middle age = 0.018* | |||||
| Young VS Old age = 0.011* | |||||
| Middle VS Old age = 0.017* | |||||
| Erector spinae | |||||
| Right side | 45.33 ± (14.67) | 53.8 ± (16.299) | 59.16 ± (14.827) | 13.18 | Over all P-value = 0.001* |
| Young VS Middle age = 0.003* | |||||
| Young VS Old age = 0.001* | |||||
| Left side | 44.16 ± (15.5) | 53.29 ± (17.481) | 60.37 ± (16.746) | 15.123 | Over all P-value = 0.001* |
| Young VS Middle age = 0.003* | |||||
| Young VS Old age = 0.001* |
*Statistical significant.
| Fatty infiltration (%) | Young age | Middle age | Old age | F | Overall P-value |
|---|---|---|---|---|---|
| L5/S1 Multifidus | |||||
| Right side | 46.06 ± (15.574) | 55.35 ± (14.933) | 62.7 ± (17.363) | 17.445 | Over all P-value = 0.001* |
| Young VS Middle age = 0.001* | |||||
| Young VS Old age = 0.001* | |||||
| Middle VS Old age = 0.032* | |||||
| Left side | 46 ± (14.174) | 55.86 ± (13.877) | 64.22 ± (19.373) | 21.366 | Over all P-value = 0.001* |
| Young VS Middle age = 0.001* | |||||
| Young VS Old age = 0.001* | |||||
| Middle VS Old age = 0.010* | |||||
| Erector spinae | |||||
| Right side | 52.13 ± (16.048) | 59.83 ± (17.957) | 63.66 ± (17.086) | 7.665 | Over all P-value = 0.001* |
| Young VS Middle age = 0.020* | |||||
| Young VS Old age = 0.001* | |||||
| Left side | 51.28 ± (17.975) | 59.69 ± (18.483) | 66.46 ± (19.164) | 10.627 | Over all P-value = 0.001* |
| Young VS Middle age = 0.019* | |||||
| Young VS Old age = 0.001* |
*Statistical significant.
1) At level L3/4:
There was a significant relationship between the age groups and CSA of the left MF side (P-value = 0.006). FI was noted to be significantly higher in old age in both sides of the MF and ES muscles (P-value < 0.05).
2) At level L4/5:
The CSA was significantly higher on both sides of MF muscle among young age (Right side P-value = 0.007, Left side P-value = 0.032). Regarding FI of MF and ES muscles, the results were higher on both muscles sides in old age (P-value < 0.05).
3) At level L5/S1:
There was no significant relationship between CSA on both sides of the MF & ES muscle and age groups. In contrast, there was a statistically significant relationship between FI on both sides of the MF & ES muscle and age groups (P-value = 0.001 at both sides), with a FI higher in old age.
Weakness in the paravertebral muscles is accepted as one of the reasons for disc herniation [
In our study, the results show that the predominance of discopathy involvement is at L4/5, which is consistent with the results of Suthar et al. [
On the other hand, our findings reveal the CSA of ES muscles is inversely proportionate to the craniocaudally lengths of the intervertebral discs (L1/2 to L5/S1). This is inconsistent with Urrutia et al., (2018) [
There was no statistically significant difference in our study between ES muscles, and discopathy status among above, below, and at predominant discopathy level. This result is inconsistent with [
These results give guidance to the correlation between increasing FI ratio and discopathy level. A higher fat ratio in paraspinal muscles composition was observed below the discopathy involvement level, especially in MF muscles. The current results are very close to another study which showed that severe disc degeneration at all intervertebral levels was associated with a high-fat content of the paraspinal muscles [
In the same context, variations in muscle composition were observed, with greater FI on the side and at spinal levels adjacent to the disc herniation [
In the current study, the results show that at the lower three vertebral levels L3/4, L4/5, and L5/S1, there is an association between the age groups and both sides of the paraspinal muscles FI ratio. However, there is no association between the age groups and CSA, except only on the left side of the MF muscle at L3/4 & L4/5. While several studies showed no association between CSA and age [
A limitation of this study is obtaining the data by one expert investigator manually drawing the border of the MF & ES muscles at the L3/4, L4/5L, L5/S1 levels. Automated techniques, if used, could result in less rate-dependent results. Also, the CSA and FI % of MF & ES were measured using ImageJ software, which has been utilized by previous studies but is not FDA approved.
The quantification threshold pixel technique for the paraspinal muscles of lumbosacral MRI is a useful, simple, non-invasive technique to distinguish between the atrophic changes like CSA size and change of FI ratio. It does also provide more clinical data related to the diagnosis of discopathy patients. Increasing FI ratio seems to correlate with discopathy level and severity, with the higher fat ratio in paraspinal muscles composition below the discopathy involvement level.
We would like to thank Dr. Nahed al Laham, Dr. Walaa Mousa, Dr. Mohab Mousa, Dr, Abdalraheem Mousa, Mousa Alnahhal and Dr. Ahmad Naijm for their encouragement and contribution to this paper. Also, we would like to thank PAMA for their continuous assistance to support research avenues and raise standards of medical care in the Gaza Strip.
The study was funded by Palestinian American Medical Association (PAMA).
The authors declare no conflicts of interest regarding the publication of this paper.
Mousa, M., Al Ajerami, Y., Shab, K.A., Matar, M., Matar, M., Jaber, S., Jaber, F.S., Mousa, A.A., Jaber, A. and Alhoubi, A. (2022) Quantification Threshold Pixel Technique of Magnetic Resonance Imaging in Paraspinal Muscles Atrophy among Discopathy Patients. Open Journal of Medical Imaging, 12, 48-66. https://doi.org/10.4236/ojmi.2022.122006