Intra-rater reliability of the Modified Modified Ashworth Scale (MMAS) in the assessment of upper-limb muscle spasticity

The aim of this study was to investigate the intra-rater reliability of the Modified Modified Ashworth Scale (MMAS) in the upper limb of patients with hemiparesis and to determine the effect of pain and contracture presence on the reliability of the MMAS. For this test-retest study 30 patients with hemiparesis were included. One physiotherapist using the MMAS, randomly rated the spasticity of shoulder adductors, elbow flexors, and wrist flexors in the affected upper limb of each patient with hemiparesis twice with at least a 1 week interval between testing sessions. The presence of pain and contracture during passive stretch was recorded. The magnitude of the contracture was measured by a goniometer. The quadratic weighted kappa statistics was very good for the upper limb spasticity (κw= 0.84). Intra-rater reliability was good for shoulder adductors (κw=0.75), and very good for elbow flexors and wrist flexors (κw 0.86 and 0.90, respectively). There were no differences between the weighted kappa values for muscle groups (p>0.05). The intra-rater reliability was also good in the presence of pain or contracture. The MMAS had very good intra-rater reliability in the assessment of upper limb spasticity in patients with hemiparesis. The presence of pain during shoulder abduction or contracture of the shoulder adductors had no influence on the reliability of the MMAS (κ w=0.75, 0.77, respectively).