Force measuring technology has been around for decades but has only recently become more affordable and accessible to the mass physiotherapy market. The ability to objectively measure force and track changes over time provides the patient with a source of motivation, takes the guess work out of manual strength testing, provides us with deeper insights into force production and provides funders with objective measures of progress.

​With increasing amounts of time and money being spent on equipment and collecting force data, maybe it’s a good time to pause and consider what value we are getting from these devices in our shoulder rehabilitation?

A few weeks ago I wrote a post about the level of clinical competency required at specialist levels of physiotherapy practice which generated a bit of interest. I mentioned that my experience of working at this level (compared with other levels of practice) is the expectation that the specialist physiotherapist will have a solution we are others have failed. Often we are ‘expected to know’. 

In the previous post I discussed some of the factors that contribute to ‘complexity’. So how do I approach and interpret my assessment and make decisions about appropriate treatment given that many people I see have already had many investigations and treatment, often from very competent professionals?

Shoulder pain, disability and psychosocial dimensions: Profile of patients attending shoulder physiotherapy clinics.
 
White, R. J., Olds, M., Cadogan, A., Betteridge, S., & Sole, G. (2022). Shoulder pain, disability and psychosocial dimensions across diagnostic categories: Profile of patients attending shoulder physiotherapy clinics. New Zealand Journal of Physiotherapy, 50(1), 6–20. https://doi.org/10.15619/NZJP/50.1.02

Full text link: https://pnz.org.nz/Attachment?Action=Download&Attachment_id=2436

For me the most fulfilling part of any publication is the discussion and clinical applications where the rubber hits the road. There were so many interesting findings from this study. We've summarised a few of the key findings in this infographic. I've provided a few other reflections on the practicalities of collecting the data in the clinical setting here:

This infographic give a summary of a case I saw in 2021. This highlights the importance of red flag screening in physiotherapy. Click here for more information about red flag screening in physiotherapy. 

Does grip strength correlate with rotator cuff strength in patients with atraumatic shoulder instability?

Turabi R, Horsely I, Birch H, Jaggi A. Does grip strength correlate with rotator cuff strength in patients with atraumatic shoulder instability? Bulletin of Faculty of Physical Therapy. 2022;27(1):1.

Objectively measuring rotator cuff strength (‘peak force’ to be exact, but that’s a post for another day) in the clinic can be challenging in certain patients, when time is an issue, when patient strength exceeds therapist strength and when you don’t have the right equipment and set-up to obtain accurate and repeatable measures.
I’ve been following a thread of articles lately demonstrating very close agreement between measures of rotator cuff strength and grip strength, the latest looking at the relationship between grip strength and internal/external rotation force measures in people with atraumatic instability. Approx. 2/3 of my clinical caseload are young people with atraumatic shoulder instability and regaining rotator cuff function (including strength) is a critical part of rehabilitation. However, some are not able to attain optimal shoulder strength test positions, and unless you have a reasonable amount of time and the right equipment (and set-up to obtain accurate and reliable measures), direct measures of rotator cuff strength can be difficult to obtain.

The simple method of measuring grip strength used in this study produced peak force values that correlated with internal and external rotation peak isometric force values in this patient group (r2 0.70 for the statos out there). Previous studies have produced r2 values up to 0.91 for the correlation between grip strength and external rotation strength (strong correlation).

This means that grip strength may provide a simple, quick, convenient and relatively cheap method of indirectly tracking changes in rotator cuff function (peak force) with the following clinical applications:
▪️ for patients who can’t tolerate typical shoulder strength testing positions (due to pain, stiffness, apprehension or fear)
▪️ can be used by small therapists working with stronger patients
▪️ where space, time or access to equipment are limited
▪️ can be used as a 'field' measure of monitoring rotator cuff function in upper limb sports (e.g throwing, swimming).
 
Full text link: https://link.springer.com/content/pdf/10.1186/s43161-021-00059-3.pdf