The nosological profile of 71 patients with NMS was as follows: 13 patients with MD, 12 with SMA, 14 with DMD and 32 with CP(Table 1). Male predominated (63% vs 37%). The average age was 14.0 ± 3.61 years old. The angle of the main scoliotic curve ranged from 13.8⁰Cobb to 152.6⁰Cobb (mean 70.87 ± 27.99⁰Cobb, Table 2).
Table 1
Distribution of selected patients of with neuromuscular scoliosis by nosological profiles, gender and age (N = 71 patients)
| MD (n = 13) | SМА (n = 12) | DMD (n = 14) | CP (n = 32) | Total(n = 71) |
Males | 9 | 7 | 9 | 20 | 45 |
Females | 4 | 5 | 5 | 12 | 26 |
Age (years old) | 14.0 ± 4.40 | 11.3 ± 4.37 | 15.4 ± 1.55 | 14.5 ± 3.17 | 14.0 ± 3.61 |
Table 2
Major measured radiographic parameters in four groups of patients with neuromuscular scoliosis before surgery (N = 71 patients)
NMS group | MD (N = 13) | SМА (N = 12) | DMD (N = 14) | CP (N = 32) | Total (N = 71) |
Measurements | Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD |
Major scoliotic curve, Cobb | 69.67 ± 24.29 (N = 12) | 78.20 ± 26.47 (N = 12) | 53.41 ± 24.66 (N = 14) | 76.20 ± 29.02 (N = 32) | 70.87 ± 27.99 (N = 70) |
Secondary scoliotic curve, Cobb | 52.34 ± 25.81 (N = 5) | 39.94 ± 28.49 (N = 5) | 32.30 ± 10.59 (N = 4) | 62.40 ± 11.74 (N = 2) | 44.71 ± 23.14 (N = 16) |
Pelvic obliquity, Cobb | 10.28 ± 10.50 (N = 13) | 18.46 ± 8.25 (N = 12) | 17.99 ± 7.76 (N = 14) | 13.87 ± 10.98 (N = 32) | 14.79 ± 10.13 (N = 71) |
Thoracic kyphosis Th5-12, Cobb | 28.39 ± 24.50 (N = 13) | 41.44 ± 27.46 (N = 12) | 5.99 ± 22.42 (N = 14) | 30.97 ± 21.12 (N = 32) | 27.34 ± 25.37 (N = 71) |
Lumbar lordosis L1-S1, Cobb | 58.97 ± 19.97 (N = 13) | 46.58 ± 22.64 (N = 12) | 30.69 ± 39.82 (N = 14) | 65.81 ± 39.10 (N = 32) | 54.38 ± 36.15 (N = 71) |
CP - cerebral palsy, DMD - Duchenne muscular dystrophy, MD – muscular dystrophy, N - number of patients, NMS – neuromuscular scoliosis, SD - standard deviation, SMA - spinal muscular atrophy |
Mean FIM score in the whole NMS group before surgery was 49.7 ± 32.02, with a predominance of non-ambulatory patients (89% vs 11%). Among patients with CP were 6 ambulatory and 26 non-ambulatory cases (GMFCS IV-V).
CT of the chest demonstrated significant deviation in four patients: atelectasis, hypoectasis and lung fibrosis. MRI of the spine did not reveal any significant pathology. Spirometry was done in 45 patients and showed variable results from absence of lung function violations (13 patients) to extremely severe dysfunction (five patients). The rest of the patents (17 patients) had mild decreasing of respiratory function. Spirometry could not be done in 26 patients due to peculiarities of mental and physical development (the patients could not execute instructions, or procedure was not effective).
In group DMD there were slightly more mild scoliosis than other groups (DMD 53.41 ± 24.66⁰Cobb vs MD 69.67 ± 24.29⁰Cobb, SMA 78.20 ± 26.47⁰Cobb, CP 76.20 ± 29.02⁰Cobb, p = 0.076).
S-shaped scoliosis with a secondary scoliotic curve were relatively common in patients with MD (38%), SMA (42%) and DMD (29%), and less often in patients with cerebral palsy (2 patients, 6%), everyone else had a C-shaped scoliosis (Table 2).
Pelvic obliquity was significantly less in MD patients (10.28 ± 10.50⁰Cobb, p = 0.047), with a relatively uniform distribution among the other nosological groups (Table 2, Fig. 1a).
The tendency to thoracic hypokyphosis, and sometimes even thoracic lordosis, was more pronounced in the DMD group (p = 0.004) (Fig. 1b and Fig. 2).
More pronounced lumbar hyperlordosis with extremely pronounced rotation occurred in CP patients (p = 0.003) (Fig. 1c and Fig. 3).
Growth-friendly instrumentation without pelvic screws was implanted for 14 patients (growing rod system), and the final correction with pelvic fixation produced for 57 patients. The main types of pelvic fixation were sacral (S1, S2 bilateral pedicle screws) and iliac screws (iliac or S2 alar iliac screws). Osteotomies, excluding facetectomy, were not performed in any patient. Allobone grafts were usually used for additional fusion. Operating time were longest in patients with CP (217.69 ± 68.05 min, p = 0.035), with relatively little blood loss (342.81 ± 197.34 ml) (Table 3). The greatest blood loss was observed in patients with SMA (438.17 ± 262.96 ml, p = 0.177) (Table 3). Intraoperative neurophysiological neuromonitoring (IONM) was done in 21 patients (spontaneous electromyography and motor evoked potentials recording) and in most cases it was unstable basally or not called up, most likely due to muscle dystrophy, pathology of the spinal cord path or cortical atrophy.
Table 3
Blood loss, surgery time and length of hospital stay (N = 71 patients)
NMS group | MD (N = 13) | SМА (N = 12) | DMD (N = 14) | CP (N = 32) | Total (N = 71) |
Measurements | Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD |
Blood loss (mL) | 378.46 ± 250.53 | 438.17 ± 262.96 | 340.00 ± 165.34 | 342.81 ± 197.34 | 364.90 ± 212.72 |
Surgery duration (min) | 177.31 ± 43.10 | 181.67 ± 49.14 | 190.71 ± 51.06 | 217.69 ± 68.05 | 198.89 ± 59.54 |
Length of hospital stay (days) | 29.00 ± 10.85 | 25.08 ± 4.44 | 23.31 ± 7.60 | 19.59 ± 6.59 | 22.97 ± 8.13 |
CP - cerebral palsy, DMD - Duchenne muscular dystrophy, MD – muscular dystrophy, N - number of patients, NMS – neuromuscular scoliosis, SD - standard deviation, SMA - spinal muscular atrophy |
Severe post-hemorrhagic anemia and the need for blood transfusion occurred in 38 patients (53.5%). All patients after surgery performed CT of the spine, significant screws malposition was not found.
Average time of in-patient treatment was 22.97 ± 8.1 days (from 9 to 55 days), which is 2-2.5 times more than most patients after spinal deformity correction in our hospital. The longest hospital stay was in patients with MD (29.00 ± 10.85 days, p = 0.189), then in SMA (25.08 ± 4.44 days) and DMD (23.31 ± 7.60 days), and the shortest in patients with CP (19.59 ± 6.59 days) (Table 3).
Moderate scoliosis correction was seen in all groups measuring 45% in MD, 47% in SMA, 61% in DMD and 63% in CP (Table 2 vs Table 4). Correction of the pelvic obliquity was 62%, 50%, 65% and 67% in the groups, respectively (Table 2 vs Table 4). DMD thoracic hypokyphosis (p = 0.001) and CP lumbar hyperlordosis (p = 0.001) was more rigid to surgical correction.
Table 4
Major measured radiographic parameters in following patients with neuromuscular scoliosis 7–21 days after surgery (N = 71 patients)
NMS group | MD (N = 13) | SМА (N = 12) | DMD (N = 14) | CP (N = 32) | Total (N = 71) |
Measurements | Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD |
Major scoliotic curve, Cobb | 38.78 ± 14.53 (N = 12) | 42.07 ± 21.88 (N = 12) | 21.16 ± 16.89 (N = 14) | 28.21 ± 17.57 (N = 32) | 30.99 ± 18.91 (N = 70) |
Secondary scoliotic curve, Cobb | 34.62 ± 18.35 (N = 5) | 33.90 ± 17.45 (N = 5) | 18.90 ± 7.71 (N = 4) | 19.80 ± 11.17 (N = 2) | 28.26 ± 15.55 (N = 16) |
Pelvic obliquity, Cobb | 3.88 ± 3.41 (N = 13) | 9.24 ± 5.75 (N = 12) | 6.30 ± 6.57 (N = 14) | 6.18 ± 6.12 (N = 32) | 6.30 ± 5.86 (N = 71) |
Thoracic kyphosis Th5-12, Cobb | 25.95 ± 12.70 (N = 13) | 16.24 ± 8.86 (N = 12) | 9.72 ± 12.29 (N = 14) | 27.00 ± 14.00 (N = 32) | 21.58 ± 14.31 (N = 71) |
Lumbar lordosis L1-S1, Cobb | 48.48 ± 13.07 (N = 13) | 39.02 ± 7.67 (N = 12) | 47.21 ± 16.10 (N = 14) | 57.03 ± 20.80 (N = 32) | 50.48 ± 17.98 (N = 71) |
CP - cerebral palsy, DMD - Duchenne muscular dystrophy, MD – muscular dystrophy, N - number of patients, NMS – neuromuscular scoliosis, SD - standard deviation, SMA - spinal muscular atrophy |
Unfortunately, X-rays evaluation one year after surgery could not be performed in all patients, which is due to the large territory of the country, the difficulties of transporting such patients, which often takes 2–3 days, COVID-19 trip restrictions, as well as the poor quality of X-ray at the living place (impossibility to perform vertical X-ray images of the entire spine). In addition, some of these patients (1 with DMD and 1 with CP) did not take lateral X-ray on out-patient clinic at the living place for unclear reasons. Only 45 cases came up for analysis. Evaluation of the results one year after surgery showed average loss of scoliosis correction of 0.57 ± 8.96° Cobb, 0.56 ± 17.09°Cobb, 1.72 ± 6.48°Cobb and 6.92 ± 9.24°Cobb during a year, respectively for MD, SMA, DMD and CP (Table 4 vs Table 5). FIM score was also measured only in 45 patients, among them 33 patients (46%) had improving and patients (27%) had deterioration in functional independents. The average postoperative FIM score 1 year after surgery was 47.30 ± 30.43 (vs preoperative 49.7 ± 32.02). In addition, one patient with CP died 6 month after surgery because of acute cardiorespiratory insufficiency of an unknown cause.
Table 5
Major measured radiographic parameters in following patients with neuromuscular scoliosis 1 year after surgery (N = 45 patients)
NMS group | MD (N = 7) | SМА (N = 9) | DMD (N = 7) | CP (N = 22) | Total (N = 45) |
Measurements | Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD |
Major scoliotic curve, Cobb | 36.64 ± 24.54 (N = 7) | 45.22 ± 23.30 (N = 9) | 20.54 ± 16.12 (N = 7) | 30.72 ± 12.51 (N = 22) | 32.96 ± 18.73 (N = 45) |
Secondary scoliotic curve, Cobb | 40.23 ± 34.74 (N = 3) | 17.27 ± 4.05 (N = 3) | 21.20 (N = 1) | 27.65 ± 23.26 (N = 2) | 27.67 ± 21.87 (N = 9) |
Pelvic obliquity, Cobb | 3,41 ± 5.4 (N = 7) | 12.61 ± 6.7 (N = 9) | 6.20 ± 4.76 (N = 7) | 5.45 ± 5.26 (N = 22) | 6.68 ± 6.17 (N = 45) |
Thoracic kyphosis Th5-12, Cobb | 28.14 ± 7.99 (N = 7) | 25.57 ± 23.03 (N = 9) | 10.62 ± 9.10 (N = 6) | 23.70 ± 13.91 (N = 21) | 22.99 ± 15.49 (N = 43) |
Lumbar lordosis L1-S1, Cobb | 56.60 ± 6.01 (N = 7) | 45.27 ± 13.89 (N = 9) | 38.63 ± 12.77 (N = 6) | 56.58 ± 15.29 (N = 21) | 51.71 ± 14.89 (N = 43) |
CP - cerebral palsy, DMD - Duchenne muscular dystrophy, MD – muscular dystrophy, N - number of patients, NMS – neuromuscular scoliosis, SD - standard deviation, SMA - spinal muscular atrophy |