Research Summary

Nicole Payne Biology 1610 Professor Daniel Carpenter Summary of Research Article

Summary: Myofascial force transmission in sacroiliac joint dysfunction increases anterior translation of humeral head in contralateral glenohumeral joint Introduction​: The Purpose of this article is to better understand the correlation sacroiliac joint dysfunction proposes on the opposite shoulder Joint. Sacroiliac Joint Dysfunction is altered functionality of the SI joint due to impaired physical structures such as ligaments, connective tissue, or articulating bones. The SI joint acts as a connecting point for the lumbosacral region and the appendicular skeleton. Studies have linked SJD with weakened motor function of the upper cervical spine, impact of load transfer in legs and feet, as well as hamstring tension and mobility. A better understanding of SJD can aid clinicians in more effectively diagnosing and treating patients with musculoskeletal issues. Myofascial networks referred to as the posterior oblique sling and the anterior oblique sling create continuity from the SI joint to the opposite shoulder joint. Tensegrity principles support the notion that lumbosacral issues can affect the opposing glenohumeral joint due to altered myofascial force transmission.

Anterior and

posterior myofascial slings work synergistically. If there is an imbalance in load transfer regarding either anterior or posterior muscular slings, compensation of the antagonist sling will occur. The hypothesis states an increased anterior translation of the contralateral shoulder joint of individuals with SJD when compared bilaterally and to matched control subjects. Method​: A sample size of 20 participants with SJD was obtained from an outpatient facility. The examination for diagnosing SJD consisted of a series of tests administered by one clinician. Positive results from 4 out of the 5 tests diagnosed the participants with SJD. Also, 20 healthy participants qualified as matched controls based on age, weight, height, and body mass index. The control group had no previous shoulder injuries, restrictions, or pain in the past 3 months

and no history of shoulder surgery, pathologies, or impaired function. A Radiologist used Ultrasonography imaging to gather data on the resting position of the humeral head, the posttranslational distance of the humeral head, and the anterior translation of the humeral head regarding both test groups. Results: The shoulder opposite of the SJD revealed a significant anterior translation when compared to the other shoulder. Participants with SJD compared the contralateral shoulder joint position to their matched controls. When comparing the resting position of the humeral head and posttranslational distance of the humeral head with the matched control group, results disclosed a notable amount of anterior translation in the contralateral GHJ of participants with SJD. Discussion: Myofascial force transmission influences the biomechanics of the musculoskeletal system. When there is altered load transfer through the fascia, tension is transmitted to neighboring tissues, ligaments, and joints. A prestressed spring system acts to balance tension on any joint through antagonistic contractions. This can affect the resting position of any joint. The posterior and anterior oblique slings act as a prestressed spring system for the GHJ. This suggests that reduced force transmission of the posterior oblique sling due to SJD intrinsically increases the tension via anterior oblique sling, thus increasing the anterior translation of the GHJ. This study supports that SJD decreases myofascial force transmission of the posterior oblique sling, therefore, giving a better understanding of the biomechanical effects associated with the contralateral musculoskeletal system.

Reference Leonard, J. H. (2014). Myofascial force transmission in sacroiliac joint dysfunction increases anterior translation of humeral head in contralateral glenohumeral joint. ​Polish Annals of Medicine​, ​21​(2), 103-108. doi:https://doi.org/10.1016/j.poamed.2014.07.007