If a patient has a trigger point at shoulder or upper back area, his function of shoulder is influenced by that. We may assess the severity of myofascial pain syndrome or the effect of treatment by shoulder function test.

The purpose of this study was to compare shoulder function test between persons with and without trigger point and to assess the correlation of shoulder function test with the duration of disease or the number of affected muscles.

We examined 40 myofascial pain syndrome patients and 27 normal control subjects and concluded the following,

1) The patients with trigger point revealed significantly lower score in shoulder function test than the one without trigger point.

2) All the items in shoulder function test except position and power are affected in myofascial pain syndrome.

3) There is no correlation between shoulder function test with duration of myofascial pain syndrome.

4) There is a tendency the increasing number of trigger points are the lower score of shoulder function test, but not significant.