Subacromial pain syndrome (SIS) is a common cause of shoulder pain, estimated to be the cause for up to half of incident cases. Typically, pain is generated with elevation of the arm above the head though it can occur with rest in patients with SIS.There is evidence of central sensitization in those who experience chronic shoulder pain from SIS. Central sensitization is an augmentation of the nociceptive pathways of the central nervous system that is characterized by local and generalized lowered pain thresholds and an exaggerated pain response to painful and non painful stimulation.Mobilization with movement (MWM) technic is a kind of manual therapy and it is often used by clinicians for the treatment of musculoskeletal diseases. Usually manual therapy is used for its peripheral effects, however it also produces central analgesic effects activating descending anti-nociceptive pathways for a short period of time (30 - 35 mins.). Some speculate that repeated sessions of manual therapy may result in a long term activation of descending anti-nociceptive pathways. However, there is no evidence of this mechanism available yet. Therefore, the aim of this study is to investigate the effect of MWM on central sensitization (primary aim) and shoulder functions (secondary aim) in patients with SIS.

Inclusion Criteria:

• To have confirmed unilateral subacromial pain (positive testing at Neer Impingement and Hawkins-Kennedy tests),
• To have <40 score in central sensitization inventory.

Exclusion Criteria:

• To have bilateral subacromial pain,
• To have any pathology (except subacromial pain) that give rise to central sensitization (This pathologies are summarized in central sensitization inventory - part B)
• To have severe osteoarthritis or subluxation in shoulder joint,
• To have adhesive capsulitis,
• Being treated with physiotherapy for this disorder at least one month before the start of the study.
• To have severe cervical or lumbar radiculopathy,