Ultrasound examination of m. erector spinae in patients with thoracic scoliosis after dynamic and rigid fixation

Objective. To assess the condition and functional parameters of m. erector spinae in patients who underwent dynamic anterior and rigid posterior fixation for thoracic scoliosis, using ultrasound diagnostics (US) and a proprietary methodology.

Materials and Methods. The comparative study involved 95 patients aged 15–55 years with idiopathic right-sided thoracic scoliosis (Cobb angle 35–60°): 33 of them after dynamic fixation, 32 after rigid fixation, and 30 patients awaiting surgery (control group). The follow-up period exceeded 12 months. Ultrasound examination included measuring of the fiber pennation angle, muscle thickness, contractility index, and relative asymmetry at the apex of the scoliotic curve. Measurements were performed in two patient positions: at rest and during maximum extension (30°, controlled by a goniometer).

Results. Statistically significant differences (p ≤ 0.05) between the groups were found. At rest, the pennation angle after dynamic fixation (20.06° ± 0.15°) was 26.5% higher than after rigid fixation (15.85° ± 0.62°), but lower than control values (23.57° ± 0.93°). The thickness of m. erector spinae with dynamic fixation (1.23 cm ± 0.01 cm) was close to the control (1.35 cm ± 0.02 cm), whereas with rigid fixation  a pronounced decrease in thickness was observed (0.89 cm ± 0.01 cm). During extension (30°), the pennation angle in patients operated on with the dynamic system sharply increased to 39.5° (close to the control value of 40.5°), which was 2.4 times higher than the indicator (16.2°) in the group with rigid fixation. The thickness of m. erector spinae (2.15 cm ± 0.05 cm) under load after dynamic fixation corresponded to the control (2.20 cm ± 0.03 cm), while rigid fixation showed thinning (1.21 cm ± 0.14 cm). The mean contractility index after dynamic fixation was significantly lower (p < 0.05) than that (84.65% ± 0.35%) after rigid fixation and close to the control value (53.9%), indicating preservation of muscle contractility. Relative asymmetry was minimal in the dynamic fixation group (1.6%) compared to that in the rigid fixation (2.24%) and control (2.96%) groups.

Conclusion. The ultrasound technique used in the study demonstrated high efficiency in assessing the condition of the paraspinal muscles. Anterior dynamic fixation for thoracic scoliosis provided the preservation of m. erector spinae functional activity, the maintenance of natural contraction and improved muscle symmetry, whereas posterior rigid fixation was accompanied by structural changes, including reduced elasticity and degeneration of muscle fibers.

1. Yaman O, Dalbayrak S. Idiopathic scoliosis. Turk Neurosurg. 2014;24:646–657. DOI: 10.5137/1019-5149.JTN.8838-13.0

2. Stokes IA. Mechanical effects on skeletal growth. J Musculoskelet Neuronal Interact. 2002;2:277–280.

3. Yagi M, Machida M, Asazuma T. Pathogenesis of adolescent idiopathic scoliosis. JBJS Rev. 2014;2:e4. DOI: 10.2106/JBJS.REV.M.00037

4. Yagi M, Hosogane N, Watanabe K, Asazuma T, Matsumoto M. The paravertebral muscle and psoas for the maintenance of global spinal alignment in patient with degenerative lumbar scoliosis. Spine J. 2016;14:451–458. DOI: 10.1016/j.spinee.2015.07.001

5. Diab AA. The role of forward head correction in management of adolescent idiopathic scoliotic patients: a randomized controlled trial. Clin Rehabil. 2012;26:1123–1132. DOI: 10.1177/0269215512447085

6. Lenke LG, Betz RR, Clements D, Merola A, Haher T, Lowe T, Newton P, Bridwell KH, Blanke K. Curve prevalence of a new classification of operative adolescent idiopathic scoliosis: does classification correlate with treatment? Spine (Phila. Pa. 1976). 2002;27:604–611. DOI: 10.1097/00007632-200203150-00008

7. Newton PO, Bartley CE, Bastrom TP, Kluck DG, Saito W, Yaszay B. Anterior spinal growth modulation in skeletally immature patients with idiopathic scoliosis: a comparison with posterior spinal fusion at 2 to 5 years postoperatively. J Bone Joint Surg Am. 2020;102:769–777. DOI: 10.2106/JBJS.19.01176

8. Pehlivanoglu T, Oltulu I, Erdag Y, Akturk UD, Korkmaz E, Yildirim E, Sarioglu E, Ofluoglu E, Aydogan M. Comparison of clinical and functional outcomes of vertebral body tethering to posterior spinal fusion in patients with adolescent idiopathic scoliosis and evaluation of quality of life: preliminary results. Spine Deform. 2021;9:1175–1182. DOI: 10.1007/s43390-021-00323-5

9. Колесов С.В., Переверзев В.С., Пантелеев А.А., Швец В.В., Горбатюк Д.С. Первый опыт вентральной динамической коррекции сколиозов у подростков с законченным ростом и взрослых: хирургическая техника и ближайшие результаты. Хирургия позвоночника. 2021;18(3):19–29. [Kolesov SV, Pereverzev VS, Panteleyev AA, Shvets VV, Gorbatyuk DS. The first experience of anterior dynamic correction of scoliosis in adolescents with complete growth and adults: Surgical technique and immediate results. Russian Journal of Spine Surgery (Khirurgiya Pozvonochnika). 2021;18(3):19–29]. DOI: 10.14531/ss2021.3.19-29 EDN: DBPVYY

10. Переверзев В.С., Колесов С.В., Казьмин А.И., Морозова Н.С., Швец В.В. Вентральная динамическая или дорсальная транспедикулярная коррекция и фиксация при хирургическом лечении идиопатического сколиоза типа Lenke 5: сравнение отдаленных результатов. Травматология и ортопедия России. 2023;29(2):18–28. [Pereverzev VS, Kolesov SV, Kazmin AI, Morozova NS, Shvets VV. Anterior dynamic versus posterior transpedicular spinal fusion for Lenke type 5 idiopathic scoliosis: a comparison of long-term results. Traumatology and Orthopedics of Russia. 2023;30(2):18–28]. DOI: 0.17816/2311-2905-3189 EDN: DSCCDA

11. Tsai YT, Leong CP, Huang YC, Kuo SH, Wang HC, Yeh HC, Lau YC. The electromyographic responses of paraspinal muscles during isokinetic exercise in adolescents with idiopathic scoliosis with a Cobb’s angle less than fifty degrees. Chang Gung Med J. 2010;33:540–550.

12. Stokes M, Hides J, Elliott J, Kiesel K, Hodges P. Rehabilitative ultrasound imaging of the posterior paraspinal muscles. J Orthop Sports Phys Ther. 2007;37:581–595. DOI: 10.2519/jospt.2007.2599

13. Wong C, Shayestehpour H, Koutras C, Dahl B, Otaduy MA, Rasmussen J, Bencke J. Using electric stimulation of the spinal muscles and electromyography during motor tasks for evaluation of the role in development and progression of adolescent idiopathic scoliosis. J Clin Med. 2024;13:1758. DOI: 10.3390/jcm13061758

14. Lu WW, Hu Y, Luk KD, Cheung KM, Leong JC. Paraspinal muscle activities of patients with scoliosis after spine fusion: an electromyographic study. Spine (Phila. Pa. 1976). 2002;27:1180–1185. DOI: 10.1097/00007632-200206010-00009

15. Smith JM, Jones SP, White LD. Rapid Communication. Gastroenterology. 1977;72:193. DOI: 10.1016/S0016-5085(77)80340-5

16. Pan A, Cao W, Wu B, Yin L, Ding H, Guo R, Liu Y, Hai Y, Zhou L. Elasticity change of the paravertebral fascia and muscle in adolescent idiopathic scoliosis after posterior selective fusion surgery. Clin Biomech (Bristol). 2022;99:105763.DOI: 10.1016/j.clinbiomech.2022.105763

17. Peterson G, Leary SO, Nilsson D, Moodie K, Tucker K, Trygg J, Peolsson A. Ultrasound imaging of dorsal neck muscles with speckle tracking analyses – the relationship between muscle deformation and force. Sci Rep. 2019;9:13688.DOI: 10.1038/s41598-019-49916-1

18. Chertman C, Campoy Dos Santos HM, Pires L, Wajchenberg M, Martins DE, Puertas EB. A comparative study of lumbar range of movement in healthy athletes and non-athletes. Rev Bras Ortop. 2010;45:389–394.DOI: 10.1016/S2255-4971(15)30385-2

19. Narici M V, Binzoni T, Hiltbrand E, Fasel J, Terrier F, Cerretelli P. In vivo human gastrocnemius architecture with changing joint angle at rest and during graded isometric contraction. J Physiol. 1996;496:287–297. DOI: 10.1113/jphysiol.1996.sp021685

20. Kawakami Y, Ichinose Y, Fukunaga T. Architectural and functional features of human triceps surae muscles during contraction. J Appl Physiol (1985). 1998;85:398–404. DOI: 10.1152/jappl.1998.85.2.398

21. Narici M, Franchi M, Maganaris C. Muscle structural assembly and functional consequences. J Exp Biol. 2016;219:276–284. DOI: 10.1242/jeb.128017

22. Haxton H.A. Absolute muscle force in the ankle flexors of man. J Physiol. 1944;103:267–273. DOI: 10.1113/jphysiol.1944.sp004075

23. Maganaris CN, Baltzopoulos V, Sargeant AJ. In vivo measurements of the triceps surae complex architecture in man: implications for muscle function. J Physiol. 1998;512:603–614. DOI: 10.1111/j.1469-7793.1998.603be.x

24. Franchi MV, Atherton PJ, Reeves ND, Flück M, Williams J, Mitchell WK, Selby A, Beltran Valls RM, Narici MV. Architectural, functional and molecular responses to concentric and eccentric loading in human skeletal muscle. Acta Physiol (Oxf). 2014;210:642–654. DOI: 10.1111/apha.12225

25. Sinha S, Sinha U, Edgerton VR. In vivo diffusion tensor imaging of the human calf muscle. J Magn Reson Imaging. 2006;24:182–190. DOI: 10.1002/jmri.20593

26. Burwell RG, Dangerfield PH. Pathogenesis of progressive adolescent idiopathic scoliosis. Platelet activation and vascular biology in immature vertebrae: an alternative molecular hypothesis. Acta Orthop Belg. 2006;72:247–260.

27. Whyte Ferguson L. Adolescent idiopathic scoliosis: The Tethered Spine III: Is fascial spiral the key? J Bodyw Mov Ther. 2017;21:948–971. DOI: 10.1016/j.jbmt.2017.01.013

28. López-Torres O, Mon-López D, Gomis-Marzá C, Lorenzo J, Guadalupe-Grau A. Effects of myofascial release or self-myofascial release and control position exercises on lower back pain in idiopathic scoliosis: A systematic review. J Bodyw Mov Ther. 2021;27:16–25. DOI: 10.1016/j.jbmt.2021.02.017

29. Rigo M. Patient evaluation in idiopathic scoliosis: Radiographic assessment, trunk deformity and back asymmetry. Physiother Theory Pract. 2011;27:7–25. DOI: 10.3109/09593985.2010.503990

30. Kim HJ, Yang JH, Chang DG, Suk SI, Suh SW, Nam Y, Kim SI, Song KS. Long‐term influence of paraspinal muscle quantity in adolescent idiopathic scoliosis following deformity correction by posterior approach. J Clin Med. 2021;10:4790. DOI: 10.3390/jcm10204790

31. Watanabe K, Ohashi M, Hirano T, Katsumi K, Shoji H, Mizouchi T, Endo N, Hasegawa K. The influence of lumbar muscle volume on curve progression after skeletal maturity in patients with adolescent idiopathic scoliosis: a long-term follow-up study. Spine Deform. 2018;6:691–698.e1. DOI: 10.1016/j.jspd.2018.04.003

32. Hebert JJ, Koppenhaver SL, Parent EC, Fritz JM. A systematic review of the reliability of rehabilitative ultrasound imaging for the quantitative assessment of the abdominal and lumbar trunk muscles. Spine (Phila. Pa. 1976). 2009;34:E848–E856. DOI: 10.1097/BRS.0b013e3181ae625c