## 4 Discussion  
In the present study, we aimed to evaluate the impact of a comprehensive rehabilitative program on shoulder ROM, muscle activity, and functioning in a cohort of wheelchair basketball athletes. Functional shoulder alterations found in wheelchair basketball athletes in this study might reflect similar patterns in traditional overhead athletes [11]. The WUSPI index was used to detect even small levels of shoulder pain through a variety of specific functional activities for wheelchair users. The WUSPI index showed a lower value in athletes than non-athletes due to the positive impact of sport in daily life [28; 29]. Sport helps people with disabilities to overcome their disabilities more easily, increasing their motivation and functional level [29]. On the other hand, long duration of training and an intense competition program could increase the injury rate and decrease the KJOC [30] index, due to the continuous excessive use of the shoulder [31]. For wheelchair users sport participation is important, as physical activity has many benefits such as psycho-physical well-being and the reduction of fat mass, avoiding obesity [11; 29; 32]. However, a balance is needed between enjoying the benefits of physical activity and the risk of shoulder overload [4]. This is an interesting challenge in competitive sport, in which a high stress on the joint due to repetitive technical gestures, the pressing rhythm of training, and trauma during the match increase the risk of injury. Therefore, it is important to make an early diagnosis of kinematic alteration to develop a specific prevention program [4]. In this context, kinematic analysis might be an optimal diagnostic option for adequately assessing upper limb functioning, as shown also in patients affected by other diseases [16]. To plan and schedule a preventive intervention to avoid the appearance of chronic pain, a kinematic analysis was performed at baseline for each athlete for a bilateral comparison of the kinematics of the shoulder in wheelchair basketball players, which showed that the scapula in the dominant side has reduced upward rotation compared to the non-dominant side. This could be related to the development of shoulder impingement syndrome, as a reduction in upward rotation of the scapula is associated with a reduction in the subacromial space and compression of the tendon of the rotator cuff, confirming that repetitive action with the arm overhead in wheelchair basketball athletes increases the risk of shoulder impingement [33]. Non-dominant glenohumeral ROM was lower than in the dominant side, due to the shortening of the glenohumeral ligaments caused by repetitive microtrauma and shoulder overuse, since each athlete uses the non-dominant side for wheelchair control during the game and in daily life [8; 34]. The results at the end of treatment indicated a significant increase in upward scapular rotation movement and an increase in abduction and external rotation of the glenohumeral joint (as reported in Table 1). According to [PERSON] et al. [11], this improvement in the scapula and shoulder ROM could be determined by the exercise program performed and is linked to a reduction in shoulder pain. Moreover, the stress on the shoulder during wheelchair propulsion could also cause degeneration and injury of the rotator cuff [35]. This is particularly relevant in wheelchair athletes, especially those with SCI, who are predisposed to a muscle imbalance of the kinetic chain of the spine and upper limb and selective muscle weakness resulting in scapular dyskinesia, which represent potential risk factors in the development of shoulder injuries [4; 14; 35; 36]. A change in the activation pattern of the shoulder girdle muscle, such as hyperactivation of the deltoid, attracts the head of the humerus, resulting in a reduction in the subacromial space.