Читать книгу Musculoskeletal Disorders - Sean Gallagher - Страница 37

The development of RC disorders is associated with a number of factors, including personal characteristics (such as age and gender), occupational exposures, and certain sports‐related activities. Among personal characteristics, factors such as gender and age tend to be most highly implicated in RC injuries (details). In terms of physical exposures, a history of occupations involving heavy lifting and/or highly repetitive tasks has been linked to the increased risk of RC disorders, which often result in greater than average lost time from work compared to other MSDs. In terms of physical exposures, a history of occupations involving heavy lifting and/or highly repetitive tasks have been linked to increased risk of RC disorders, which often result in greater than average lost time from work compared to other MSDs. In 2014, 88,980 nonfatal shoulder injuries and illnesses occurred that involved days away from work (Bureau of Labor Statistics, 2015).

Figure 2.6 Partial and full tears in supraspinatus tendons, a rotator cuff tendon. (a) The location of the supraspinatus tendon. (b–d) X‐ray images of a partial‐thickness tear in the supraspinatus tendon. In a neutral position (b), a partial tear was not evident; hence, changes were interpreted as tendinosis. Crass position (c) and modified Crass position (d) show a hypoechoic region (arrows) interpreted as a partial tear in a fat‐suppressed T2‐weighted magnetic resonance image. (e and f) Full‐thickness tear (arrows) of a supraspinatus tendon (arrows). Neutral position (e), Crass position (f), and modified Crass position (g).

Modified from Shah, N. P., Miller, T. T., Stock, H., & Adler, R. S. (2012). Sonography of supraspinatus tendon abnormalities in the neutral versus Crass and modified Crass positions: A prospective study. Journal of Ultrasound in Medicine, 31(8), 1203–1208. doi: 10.7863/jum.2012.31.8.1203. Wiley.

High shoulder pain prevalence is often seen in athletic pursuits, particularly those requiring forceful and repetitive motions that involve throwing or other activities where the hands and/or elbows are active above the level of the shoulder. High stresses are placed on the shoulder in activities such as baseball pitching, football throwing, tennis, volleyball, and swimming. These repetitive high‐stress activities are likely to result in microdamage and damage propagation that may exceed the repair capacity of shoulder musculoskeletal tissues (Bani Hani et al., 2021).

Subacromial impingement may also occur at the subacromial joint. It is thought to be the result of fatigue in the stabilizing structures of the shoulder (the tendons and ligaments), resulting in humeral subluxation and subsequent impingement of the supraspinatus tendon between the head of the humerus and the inferior surface of the acromion. It has been reported that the most frequent shoulder diagnoses in athletes involve RC dysfunction with signs of supraspinatus tendon impingement (Baring, Emery, & Reilly, 2007; McHardy, Pollard, & Luo, 2007; Pink & Tibone, 2000). That said, there can also be degenerative changes in the joint structure itself. In one study, the frequency of radiologically detected lesions in shoulders of 152 miners using vibration tools was 40.7% and included degenerative changes (34.5%) that were mainly in the acromioclavicular joint (17.8%) (Kakosy et al., 2006).