Tuesday, 8 September 2020

Iso's in Iso: Beyond the Ball

If this isn't the best title for a blog piece on grip strengthening this year then I'll give it all up. I actually don't have much more than the title actually. Sorry. I've spent most of the morning thinking about how I help patients regain hand strength. What special tools do I utilise and what is the science behind these unique methods? Sorry again. I've got nothing for you beyond gut although I'm sure there is some science out there. 

When we talk grip strength, much of the conversation is based around differentiating between power grip and precision grip. Both types then get torn up into even more specifics. Power grip has 4 forms apparently. There's cylindrical grasp, ball grasp, hook grip and lateral prehension (thumb adduction). Pinch also has 4 forms, precision, oppositional, key pinch and chuck grip (1,2). So when I get a patient referred for rehab with the suggestion that "maybe a stress ball would help", it's hard not to feel a little superior. 

We can do better than a stress ball because rebuilding a functional hand requires more than 10 repetitions of a ball grasp 3 times a day. In fact, if I'm speaking plainly, I almost never prescribe stress ball squeezes. I find that often this type of grasp neglects to include the long flexors and the ulnar digits. Instead, I'll find strengthening exercises that replicate most what that patient needs to do and then build from there. If that's swinging a hammer, the initial focus may be on cylindrical grip. If that's holding a football, then working on a more open, ball grasp with its emphasis on intrinsic stability. If it's climbing a wall, then hook grips and flat pinch come into play. 
Not my arms, those who can do etc

My current favourite is the rice bath. It encourages composite wrist and hand movement, it facilitates all grip and pinch types, and there's a sensory component to it as well which may assist with proprioceptive feedback. The key is variation regardless of what you prefer. Use a ball, but also use a rope, or encourage wringing of a wet towel. Isometric holds of a barbell will build hook grip strength, but hanging from a chin up bar will encourage cylindrical grip. Remember that there is a clear correlation between grip strength and shoulder stability(3). Work in pronation and supination, sitting and standing, shoulder abduction and flexion. 

So, no science, but some sense. Have a look at how your patient grips. Use a rolled up bandage instead of a ball. Use a pillow or a handle. Empty 5 kilos of rice into a bucket. Look at what's not working, at what they need to do, and go from there. "Isos in iso", brilliant. Should have been in advertising! 

Look after those fingers,


(1) Duncan S. et al. Biomechanics of the Hand, Hand Clinics 29 (2013) 483-92
(2) Landsmeer J. Power Grip and Precision Handling, Ann Rheum Dis 21 (1962) 164                                                          (3) Horsley I. Do changes in hand grip strength correlate with rotator cuff function? Shoulder Elbow 8-2 (2016) 124-9