Pain-Related Beliefs and the Frozen Shoulder
A frozen shoulder is a relatively common condition that causes localised shoulder pain and stiffness in the glenohumeral joint, which is the main “ball and socket” joint of the shoulder. We know that beliefs, along with many other factors, are related to pain and function in many musculoskeletal conditions. But this study looked specifically at how beliefs may influence arm function in those suffering with frozen shoulder.
85 participants with frozen shoulder were given questionnaires to determine their pain intensity, arm function, pain catastrophising (view of a situation being worse than it actually is), pain-related fear, and pain self-efficacy (ability to function despite pain). Researchers then assessed the degree to which differences in pain-related beliefs could explain differences in arm function. Results show that an association was found between pain-related fear and pain self-efficacy and perceived arm function, with a slightly weaker relationship found between pain catastrophising and perceived arm function.
A lot remains unknown about frozen shoulder – including the underlying biology involved – with current research not giving us a clear understanding. Traditional understanding has focused around structural change at the joint, but new research provides evidence that some cases are caused in part by muscle guarding, which is a protective mechanism where muscles stiffen to reduce movement. This study suggests that psychological factors such as pain-related fear, catastrophising, and decreased self-efficacy might be contributing to decreased movement of the shoulder.
This doesn’t mean that the pain is not real, as we know that all pain is real – just that pain does not always directly correlate with tissue damage and there are often other factors that are contributing. This suggests that we may be able to improve arm function in those with frozen shoulder by helping to reduce pain-related fear and by increasing self-efficacy, of which exercise is a fantastic tool to do so.
De Baets, L et al. 2020. Pain-Related Beliefs are Associated with Arm Function in Persons with Frozen Shoulder. Shoulder Elb.