Problems experienced with low-profile dynamic splints.
Van Velze, Cornelia Anna
Many patients have been supplied with dorsal dynamic finger extension splints for improvement of the range of motion of stiff finger joints, The design of the splint has been developed and improved over time, but the amount of force which was applied to a finger was determined intuitively. This research was undertaken to quantify the force exerted on a finger and to desigm a splint which would ensure that the amount of force exerted on a finger was constant and reliable. Since six studies were undertaken as part of the research, different protocols were developed for each. The findings of the studies can be summarised as follows: * similar tensions in a variety of rubber bands can not consistently be identified; rubber bands which are more or less equal in length, thickness and width do not undergo the same amount of elongation when identical weights are attached to them; friction between the outrigger and the traction unit plays a major role in determining how much force is exerted on a finger; a layer of Teflon paint over the outrigger coupled with a nylon fishing line traction unit causes the least amount of friction; stainless steel tension springs provide a more reliable and consistent force than rubber bands. Finally a splint was designed, taking into account the results of the six studies. The splint consists of a thermoplastic base with Velcro attachment straps, a pre-notched copper coated welding rod dipped in Teflon paint at least 14 days before use, a traction unit made from a stainless steel tension spring with a tension of 3g/rnm, a piece of nylon fishing line and a finger sling. Although the splint was designed to ensure that the force exerted on a finger is consistent and quantifiable, it should still be tested clinically to ascertain whether the design is really practical.
A thesis submitted to the Faculty of Medicine, University of the Witwatersrand, Johannesburg for the degree of Master of Science, Occupational Therapy
Splints., Finger Injuries therapy.