Clear communication among the patients and clients, therapists and trainers, and physicians are vital to ensure that patients and clients do not pursue unnecessary and costly treatments that may do more harm than good. With this understanding of asymptomatic shoulders, therapists and trainers are likely to find the right methods to help their clients or patients to function and move better without pain.
A 2014 systematic review that was published in Journal the Shoulder and Elbow Surgery examined 30 studies (over 6,100 shoulders total) that reported rotator cuff abnormalities with age. The researchers separated the prevalence of shoulder abnormalities in four groups: (1) asymptomatic patients, (2) general population, (3) symptomatic patients, and (4) patients after shoulder dislocation. Among patients who were 20 years and younger, 29 out of 299 (9.7%) had signs of abnormalities, while 166 out of 268 (62%) patients aged 80 years and old had various abnormalities. Such prevalence occurred regardless whether the patients had symptoms or shoulder dislocation or not.
MRI imaging tend to interpret rotator cuff abnormalities as “tears” and cannot reliably or accurately determine whether the they are caused by lesions or are just normal variations or age-related changes. Like low back pain and knee pain, the thought of having “tears” or any structural damage or deviation from what is considered “normal” or “healthy” may bring unnecessary fear to patients who may think that they need to be “fixed.”
The researchers concluded: “The prevalence of rotator cuff abnormalities in asymptomatic people is high enough for degeneration of the rotator cuff to be considered a common aspect of normal human aging and to make it difficult to determine when an abnormality is new (e.g., after a dislocation) or is the cause of symptoms.”
One of the early research in this topic was published in 1995 in Journal of Bone and Joint Surgery by a team of physicians from the University of Miami. Back then, the prevalence of rotator cuff asymptomatic patients is not well-known. Like the recent review, this study also found very similar results among its sample of 96 asymptomatic subjects.
Cumulatively, 33 of 96 (34%) had signs of a rotator cuff tear; 14 had a full tear while 19 had a partial tear. No one in the 19 to 39-year-old category had a full or partial rotator cuff tear, but as the age increases, the prevalence increased to 4 to 24 percent, respectively, in the 40 to 60-year-old category. For those who were more than 60-years-old, the percentages were 28 and 26, respectively.
There are also some evidence that indicate that rotator cuff tears do not always interfere with normal function. Dr. S. Burkhart from the University of Texas Health Science Center in San Antonio examined 12 shoulders with “massive rotator cuff tears” with fluoroscopic imaging. He noted that normal function was possible as long as the posterior aspect of the rotator cuff was preserved to a point that force coupling in the transverse plane was maintained. The location of the tear was also important in considering whether normal function is maintained despite of a rotator cuff tear.
Ultrasound findings of shoulder abnormalities in one study of 51 men also found a lack of symptoms or pain, yet the such abnormalities increases in prevalence with age. However, the authors cautioned that this study is not an accurate representation of the general population because they were all men recruited from a sports medicine clinic. In addition to a likelihood of bias during subject selection, they warned, “A current absence of symptoms does not exclude the development of symptoms at a later date.” Thus, current conditions do not necessarily predict future outcomes.
One 2009 study from Journal of Bone and Joint Surgery found a correlation between shoulder strength and asymptomatic rotator cuff tears that increase with age. Among 237 subjects, shoulders with larger full-thickness rotator cuff tear had significantly decreased isolated abduction strength. However, not all asymptomatic shoulders were weaker than healthy shoulders. “We also noted that in individuals who were seventy years of age and older, the shoulders with a full-thickness tear had significantly decreased abduction strength compared with normal shoulders regardless of the size of the tear,” the authors noted.
2. How do we know cause of clients' or patients' with shoulder pain is correlated with structural damage or not?
1. Teunis T, Lubberts B, Reilly BT, Ring D. A systematic review and pooled analysis of the prevalence of rotator cuff disease with increasing age. Journal of Elbow and Shoulder Surgery. 2014 Dec;23(12):1913-21.
2. Sher JS, Uribe JW, Posada A, Murphy BJ, Ziatkin MB. Abnormal findings on magnetic resonance images of asymptomatic shoulders. Journal of Bone and Joint Surgery. 1995 Jan; 77(1):10-5.
3. Burhart SS. Fluoroscopic comparison of kinematic patterns in massive rotator cuff tears. As suspension bridge model. Clin Orthop Relat Res. 1992 Nov; (284):144-52.
4. Girish G, Lobo LG, Jacobson JA, Morag Y, Miller B, Jamadar DA. Ultrasound of the shoulder: asymptomatic findings in men. AJR Am J Roentgenol. 2011 Oct;197(4):W713-9. doi: 10.2214/AJR.11.6971.
5. Kim HM, Teefey SA, Zelig A, Galatz LM, Keener JD, Yamaguchi K. Shoulder strength in asymptomatic individuals with intact compared with torn rotator cuffs. J Bone Joint Surg Am. 2009 Feb;91(2):289-96. doi: 10.2106/JBJS.H.00219.