The Best Evidence for Rotator-Cuff Related Shoulder Pain
Let’s keep our cuffs tuff
Key points based synthesized from current evidence:
1. Psychosocial factors have a strong influence on shoulder pain (e.g. poor self-efficacy). 2. Lack of education has a direct correlation to poor outcomes. 3. Graded exercises reduce the need for surgery by up to 80%. 4.Physiotherapy exercise interventions are as effective as surgery. 5. Corticosteroids (Cortisone) injections give small and transient pain relief. 6. Corticosteroids (Cortisone) injections accelerate tendon degeneration.
Rotator-Cuff related shoulder pain encapsulates every pain sensitive structure from muscles, tendons, ligaments, nerves and bursae located in and around the shoulder. With the shoulder being a tightly knit structure, movements with compress and traction a variety of tissue to differing degrees. Subsequently making structural diagnosis difficult and inaccurate.
Structural Testing and imaging
There is more and more emerging evidence illustrating the lack of specificity and sensitivity of traditional orthopedic tests. Lewis et al (2007) demonstrated special orthopedic procedures like the Neer, Hawkin’s, full/empty can tests present with 8-9 equally active muscles when examined with indwelling electrodes. Hence, questioning their validity. ALL shoulder tissue contains nociceptors; and if peripheral Nociception (i.e. local tissue), is the driver for the sensation of pain then all clinical tests will stretch, traction and/or compress the subacromial bursae and other tissue.
Similarly, when evaluating imaging, Girish and colleagues (2011) displayed ultrasound scans on asymptomatic subjects and found shoulder abnormalities in 96% of subjects. Additionally, Frost et al (1999) used MRI scans to show there was no significant difference in imaging between symptomatic and asymptomatic subjects.
Bursitis and Cortisone
There are 6 to 12 in the shoulder. However, it is rarely the primary/sole contributor of shoulder pain. The function of a bursa is to decrease friction during movement. So the question should always be – what is causing friction in the first place? This will vary from one individual to another. Education that bursitis exists in the presence of an underlying mechanical pathology is crucial to a patient’s prognosis.
With that in mind, the use of cortisone is rapidly increasing. Mohamadi and colleagues (2017), illustrated the lack of benefit both with duration (4-8 weeks) and success rate (1 in 5) for a mild effect. Unfortunately, this presents as an even small benefit, since corticosteroids act to degenerate tendons by altering the cellular matrix of the collagen fibres. In our clinical experience, Cortisone is best utilised in conjunction with physiotherapy only when individuals are not presenting with improvements in pain after 6 weeks for treatment.
Exercise Interventions Vs. Surgery
Exercise therapy through physiotherapy is currently the best evidence based practice. GP’s should educate patients on the benefits of exercise with respect to pain reduction long-term as well as the need for surgery by up to 80% (Lewis 2007). Patients must also be educated on the time-frames for rehab (~12 weeks for shoulders) and that improvements in strength vs. pain are not always linear (expect ups and downs).
When comparing exercise to surgery there is no difference in the outcomes (up to 5 years post-op). However Physiotherapy exercise programs come in at a fraction of the cost of surgery. Additionally, a recent review by Carr and colleagues (2015) demonstrated NO significant difference in quality of life scores when comparing individuals with intact and failed/re-torn rotators post-op. Hence raising the question of relative rest with rotator-cuff related shoulder pain.
Psychosocial Factors and the way forward
Addressing psychosocial barriers and the lack of education have a great influence on patient prognosis (Chester el al, 2016). Improving health literacy to enhance a patient’s self-efficacy and optimism will aid in the promotion of regular planned exercise to tissue recovery and long-term pain relief.