Document Type : Original Articles


1 Musculoskeletal Research Center, Department of Physiotherapy, School of Rehabilitation, Isfahan University of Medical Sciences, Isfahan, Iran.

2 Department of Physiotherapy, Faculty of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran, Iran

3 Musculoskeletal Research Center, Department of Physiotherapy, School of Rehabilitation, Isfahan University of Medical Sciences, Isfahan, Iran. university of medical sciences

4 Department of Basic Sciences, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

5 Department of Neurology& Isfahan Neurosciences Research Center, Faculty of Medical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran.


Subsequent to spasticity, which is a positive impairment of stroke,neural and mechanical changes often occur in paretic muscles, affecting muscle function. The aim of this study was to find more accurate indices, which could affect decisions about spasticity treatment by investigating the relationships among neural, mechanical, functional outcomes, and clinical parameters in spastic chronic stroke patients.
This cross-sectional study investigated 45 spastic chronic stroke patients. Clinical assessments were conducted using the Modified Modified Ashworth Scale (MMAS). Neural properties including H-reflex latency and Hmax/Mmax ratio were acquired. Mechanical properties including fascicle length,pennation angle, and thickness of spastic medial gastrocnemius muscle were evaluated. Functional outcomes were evaluated by the Timed Up and Go (TUG) test and Timed 10-Meter Walk Test (10-m WTT). Spearman’s rank correlation analysis in SPSS version 22.0 was used to find correlations between parameters.
A low negative correlation was determined between MMAS and H-reflex latency (r=-0.320, P=0.032). MMAS score had a low significant relationship with pennation angle (r=0.296, P=0.049) and thickness of muscles (r=0.389,P=0.008). However, no significant correlation was found between MMAS and functional outcomes.
Based on these findings, it is clear MMAS can partly identify changes in neural and mechanical properties of spastic muscles.


  1.  Carr JH, Shepherd RB. Neurological rehabilitation: optimizing motor performance: Elsevier Health Sciences; 2010.
  2. Wissel J, Manack A, Brainin M. Toward an epidemiology of poststroke spasticity. Neurol. 2013;80(3 Supplement 2):S13-S9.
  3. Lance JW. The control of muscle tone, reflexes, and movement Robert Wartenbeg Lecture. Neurol. 1980;30(12):1303-.
  4. Dietz V, Sinkjaer T. Spastic movement disorder: impaired reflex function and altered muscle mechanics. Lancet Neurol. 2007;6(8):725-33.
  5. Galiana L, Fung J, Kearney R. Identification of intrinsic and reflex ankle stiffness components in stroke patients. Exp brain res. 2005;165(4):422-34.
  6. Ghasemi E, Khademi-Kalantari K, Khalkhali-Zavieh M, Rezasoltani A, Ghasemi M, Akbarzadeh Baghban A, et al. The Effect of Functional Stretching Exercises on Neural and Mechanical Properties of the Spastic Medial Gastrocnemius Muscle in Patients with Chronic Stroke: A Randomized Controlled Trial. J Stroke Cerebrovasc Dis : the official journal of National Stroke Association. 2018;27(7):1733-42.
  7. Hu X, Suresh NL, Chardon MK, Rymer WZ. Contributions of motoneuron hyperexcitability to clinical spasticity in hemispheric stroke survivors. Clin Neurophysiol. 2015;126(8):1599-606.
  8. Berenpas F, Martens AM, Weerdesteyn V, Geurts AC, van Alfen N. Bilateral changes in muscle architecture of physically active people with chronic stroke: A quantitative muscle ultrasound study. Clinical neurophysiology : Clin Neurophysiol. 2017;128(1):115-22.
  9. Gao F, Grant TH, Roth EJ, Zhang L-Q. Changes in passive mechanical properties of the gastrocnemius muscle at the muscle fascicle and joint levels in stroke survivors. Arch Phys Med Rehabil. 2009;90(5):819-26.
  10. Dias CP, Lanferdini FJ, Onzi EdS, Goulart NBA, Becker J, Gomes I, et al. The influence of hemiparesis on triceps surae morphological and mechanical properties in stroke survivors. Isokinet Exerc Sci. 2016;24(2):157-64.
  11. Li L, Tong KY, Hu X. The effect of poststroke impairments on brachialis muscle architecture as measured by ultrasound. Arch Phys Med Rehabil. 2007;88(2):243-50.
  12. Blackburn M, van Vliet P, Mockett SP. Reliability of measurements obtained with the modified Ashworth scale in the lower extremities of people with stroke. Phys Ther. 2002;82(1):25-34.
  13. Pradines M, Ghedira M, Portero R, Masson I, Marciniak C, Hicklin D, et al. Ultrasound structural changes in triceps surae after a 1-year daily self-stretch program: a prospective randomized controlled trial in chronic hemiparesis. Neurorehabil Neural Repair. 2019;33(4):245-59.
  14. Ghotbi N, Nakhostin Ansari N, Naghdi S, Hasson S. Measurement of lower-limb muscle spasticity: intrarater reliability of Modified Modified Ashworth Scale. J Rehabil Res Dev. 2011;48(1):83.
  15. Ansari NN, Naghdi S, Hasson S, Valizadeh L, Jalaie S. Validation of a Mini-Mental State Examination (MMSE) for the Persian population: a pilot study. Applied neuropsychology. 2010;17(3):190-5.
  16. Bakheit A, Maynard V, Shaw S. The effects of isotonic and isokinetic muscle stretch on the excitability of the spinal alpha motor neurones in patients with muscle spasticity. Eur J Neurol. 2005;12(9):719-24.
  17. Podsiadlo D, Richardson S. The timed “Up & Go”: a test of basic functional mobility for frail elderly persons. J Am Geriatr Soc. 1991;39(2):142-8.
  18. Kim KS, Seo JH, Song CG. Portable measurement system for the objective evaluation of the spasticity of hemiplegic patients based on the tonic stretch reflex threshold. Med Eng Phys. 2011;33(1):62-9.
  19. Ghotbi N, Ansari NN, Naghdi S, Hasson S, Jamshidpour B, Amiri S. Inter-rater reliability of the Modified Modified Ashworth Scale in assessing lower limb muscle spasticity. Brain injury. 2009;23(10):815-9.
  20. Angel R, Hofmann W. The H reflex in normal, spastic, and rigid subjects: studies. Arch Neurol. 1963;8(6):591-6.
  21. Huang C-Y, Wang C-H, Hwang S. Characterization of the mechanical and neural components of spastic hypertonia with modified H reflex. J Electromyogr Kinesiol. 2006;16(4):384-91.
  22. Tsai KH, Yeh C-Y, Chang HY, Chen JJ. Effects of a single session of prolonged muscle stretch on spastic muscle of stroke patients. Proceedings-National Science Council Republic of China Part B Life Sciences. 2001;25(2):76-81.
  23. Bakheit A, Maynard V, Curnow J, Hudson N, Kodapala S. The relation between Ashworth scale scores and the excitability of the α motor neurones in patients with post-stroke muscle spasticity. J Neurol Neurosurg Psychiatry. 2003;74(5):646-8.


  1. Picelli A, Tamburin S, Cavazza S, Scampoli C, Manca M, Cosma M, et al. Relationship between ultrasonographic, electromyographic, and clinical parameters in adult stroke patients with spastic equinus: an observational study. Arch Phys Med Rehabil. 2014;95(8):1564-70.
  2. Chung SG, van Rey E, Bai Z, Roth EJ, Zhang L-Q. Biomechanic changes in passive properties of hemiplegic ankles with spastic hypertonia. Arch Phys Med Rehabil. 2004;85(10):1638-46.
  3. Yang Y-B, Zhang J, Leng Z-P, Chen X, Song W-Q. Evaluation of spasticity after stroke by using ultrasound to measure the muscle architecture parameters: a clinical study. Int J Clin Exp Med. 2014;7(9):2712.
  4. Hsu A-L, Tang P-F, Jan M-H. Analysis of impairments influencing gait velocity and asymmetry of hemiplegic patients after mild to moderate stroke. Arch Phys Med Rehabil. 2003;84(8):1185-93.
  5. Freire B, Abou L, Dias CP. Equinovarus foot in stroke survivors with spasticity: a narrative review of muscle–tendon morphology and force production adaptation. Int J Ther Rehabil. 2020;27(1):1-8.
  6. Dean CM, Richards CL, Malouin F. Task-related circuit training improves performance of locomotor tasks in chronic stroke: a randomized, controlled pilot trial. Arch Phys Med Rehabil. 2000;81(4):409-17.
  7. Lamontagne A, Malouin F, Richards CL. Locomotor-specific measure of spasticity of plantarflexor muscles after stroke. Arch Phys Med Rehabil. 2001;82(12):1696-704.