All the answers in one little theory... perhaps not!

Simon "The Wiz" Whitlock showing how the DTM should be done!

If there’s a subject close to my hand therapy heart, it is the “Dart-thrower’s motion” or DTM. For the uninitiated, the DTM was coined in an attempt to describe a pattern of wrist movement that most limits motion between two important bones in the wrist, the scaphoid and the lunate. The reason my ears prick up when DTM is mentioned is that when hand surgeons and therapists first started talking about it in the late 2000’s, I started to integrate it into the management of my patients.

My DTM splint

I created a splint that was designed to limit movement to the DTM. I wrote a paper about it for the Australian Sports Physiotherapy magazine, and was an invited speaker at the International Hand Therapy conference in 2010. I also presented my splinting concept and some preliminary results at a couple of conferences in Australia.

I’ve had some great success with applying these principles, especially with those patients who were prepared to stick with the program I devised. The program involved wearing a splint that restricted motion to the DTM plane, and a progressive series of exercises and proprioceptive activities. One patient in particular stands out. I’ll call him Markos.

Markos "the Glassman" Moya (not his real name or picture!)

Markos had diagnosed mid-carpal instability. He didn’t want surgery because typically the surgery restricts wrist motion. Markos had dreams of joining the world senior’s tennis tour in 18 months’ time. He wore the splint, and was religious with his exercises. Importantly, he also addressed aspects of his tennis game, hitting flatter through the ball. I just googled him to find his is now ranked just outside the top fifty in the world for his age group. He’s living the dream, and is proof the principles work… or is he? 

Classic SL dissociation. Not that easy!

It was the IFSSH scientific committee’s report on wrist biomechanics in 2007 that focussed on the DTM. Since that time, research on the DTM has succeeded spectacularly on muddying the waters. In 2013 they updated their report.  What appeared to be so clear cut, and so useful, is now confused with definitions of different planes of DTM; of functional DTM vs pure DTM, and of potential problems with the movement. We aren’t nearly as convinced now that there is any merit in using it in rehabilitation to protect a dysfunctional joint. Questions have been asked, and answers are still being sought. Memo to self; when you think you know it all, you don’t. It’s that’s simple.

Look after those fingers,

Hamish