## 1 Introduction  
Nowadays, we observe the continuous development of professional sports, including sports for people with disabilities [1]. More and more people with disabilities are involved in professional sports. Sports associations are being established, and sponsors are increasingly willing to support athletes with disabilities. Professionalization in Paralypic sports is associated with the athletes' desire to maximize results, and thus, with increased training loads, there is an increase in injuries and traumas, consequently contributing to musculoskeletal pain in athletes. Previous studies have focused mainly on the frequency and location of musculoskeletal pain in athletes [2, 3, 4, 5, 6, 7]. However, there is a paucity of research explaining their etiopathogenesis in athletes with disabilities. The etiopathogenesis of pain in this specific group,differentiated by type, degree, and location of disability, is multifactorial. Musculoskeletal pain may be a consequence of adaptation to sport, which triggers the development of an external compensatory mechanism, which was defined by [PERSON] et al. [6] as the mechanism responsible for the adaptation of the athlete's body to specific movements resulting from a given sport [7]. On the other hand, the intrinsic compensatory mechanism is defined as self-activating changes in the musculoskeletal system that are related to the individual anatomical structure [6]. This mechanism has been identified and defined in the group of people with disabilities of the musculoskeletal system. In the case of visual impairment, the internal mechanism will not be related to anatomical structures, but only to physiological and sensory functions, i.e., the vestibular system (exteroreceptors, interoreceptors, proprioceptors, vestibular organ, kinesthetic sensation, sound perception). Therefore, it is important to identify and define compensatory mechanisms within the group of sensory impairments (vision) by stratifying the compensatory senses. This hypothesis forms the basis for the development of a theoretical model of sensory hierarchy in response to the deprivation of a sense in the control of postural stability (Figure 1). Deprivation of vision disrupts the neurocontrol of posture and its stability, which reduces overall well-being. Concurrently, the implementation of specialized unilateral training, often referred to as adaptation training, has been observed to trigger pain-related symptoms in some individuals with vision loss or impairment. It is confirmed by authors who indicate that visual impairments are associated with neck, shoulder, and back pain [8]. In addition, musculoskeletal pain in athletes may be related to adaptation to the training load and the specificity of the sport, i.e., external compensatory mechanisms, as already demonstrated in a group of sitting volleyball players [3; 7; 9]. To the best of the authors' knowledge, there is a lack of research in this aspect in visually impaired athletes. The loss or impairment of vision causes the activation of internal compensatory mechanisms, thus adversely affecting postural stability [10], static balance [11], children's posture (higher thoracic kyphosis, lower lumbar lordosis, shoulder deviation in frontal plane, lateral deviation of the spine) [12], and locomotion [13; 14]. In childhood, postural abnormalities are observed in blind people and are perpetuated, resulting in disturbed biomechanics of habitual posture (especially sway in the sagittal plane) and motor skills. Specific adap  
Figure 1: Theoretical model of compensatory mechanism (own source). tive changes in the aspect of motor skills and the activation of internal compensatory mechanisms were observed in blind children in coordination skills such as kinesthetic differentiation, speed of reaction to sound, and motor adaptation. Above all, the authors point to limitations in free and voluntary physical activity, which may consequently lead to an increase in musculoskeletal complaints [15,16].