Published online Apr 18, 2020. doi: 10.5312/wjo.v11.i4.206
Peer-review started: September 17, 2019
First decision: December 23, 2019
Revised: January 15, 2020
Accepted: February 8, 2020
Article in press: February 8, 2020
Published online: April 18, 2020
Shoulder gradient has been associated with shoulder pathologies such as shoulder impingement syndrome.
To investigate if there is an association between shoulder gradient and incidence of rotator cuff tear (RCT).
A total of 61 patients with a confirmed diagnosis of RCT were included in this retrospective study. The anteroposterior radiograph of the shoulder was used to measure shoulder gradient in adduction and neutral rotation positions. The pain level was assessed with the visual analog scale for pain.
The mean age of the patients was 55.7 ± 12.3 years. The mean visual analog scale of the patients was 4.1 ± 1.2. The mean shoulder gradient was 14.11º ± 2.65º for the affected shoulder and 15.8º ± 2.2º for the unaffected shoulders. This difference was not statistically significant (P = 0.41). A difference of 1.15º ± 1.82º was found between the injured and non-injured shoulder. No significant association was found between the gradient difference of the shoulder and demographic and clinical characteristics of the patients.
Shoulder gradient is not associated with the pathology of RCT. Yet, future studies with more standardization and a larger sample size are needed to investigate the role of shoulder gradient in RCT pathogenesis further.
Core tip: Shoulder anatomical characteristics have been associated with several shoulder pathologies. We hypothesized that the shoulder gradient might be regarded as an anatomic factor affecting the occurrence of rotator cuff pathologies. Our analysis revealed no association between shoulder gradient and incidence of rotator cuff tear.