Iraj Abdollahi - Department of Physiotherapy, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
Maghsoud Eivazi - Department of Physiotherapy, Tabriz Medical Sciences University, Tabriz, Iran
Shapour Jaberzadeh - Department of Physiotherapy, School of Primary Health Care, Faculty of Medicine, Nursing andHealth Sciences, Monash University, Melbourne, Australia
Alireza Taghizadeh - Department of Physiotherapy, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
Hassan Shakeri - Department of Physiotherapy, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran

Objective: In this study the relationship between degree of spasticity and strength of knee extensor and ankle plantar flexor muscles of post stroke hemiparetic patientshasbeeninvestigated. Materials & methods: The participants of this study were 40 stroke patients whose elapsedtime of stroke onset was at least 3 months. Their age averaged 59 years. Spasticity wasmeasured with the Modified Ashworth Scale. Isokinetic muscle strength was measured withan isokinetic dynamometer. Two methods of torque normalization e subtractive and weightbased normalization e were used for comparing torques among participants. Results: Kendall’s tau-b coefficient was calculated for investigating this relationship. This coefficient was not significant for the relationship between weight based normalized data andmodified Ashworth scale (MAS) in any of each muscle groups (a Z 0.05). This coefficientwas significant for the relationship between the subtractive normalization method and MASin knee extensors (P Z 0.005, a Z 0.01) and ankle plantar flexors (P Z 0.002, a Z 0.01). Conclusion: This study suggests a negative relationship between spasticity and muscle strengthand provided evidence that spastic muscles are weaker.

Stroke;Spasticity;Muscle strength;Isokinetic