Knee walkers as we know them today don’t seem to have existed until some 30 years ago, although various types of “bent knee prostheses” have been used since the 4th Century B.C. In fact, an article published in the British Medical Journal in 1986 says that researchers have found depictions of these knee walker ancestors on vases dating back 2,400 years as well as in paintings from the 15th and 16th centuries.
The article refers to what seems to be the first modern knee walker on the market, both in its title, “Early bent knee prostheses: ancestors of K9,” and again in its final sentence: “Recent enthusiasm for Mr Reid’s K9 is certainly justified: it is a worthy descendant of a long line of walking aids.”
The K9 Knee Scooter
Still being sold where it was developed in the UK, the K9 Orthopaedic Scooter can also be viewed in the London Science Museum’s Brought to Life collection. The write-up on this site confirms that the leg trolley was an invention of necessity, which came about when Michael Reid, a managing director of a steel engineering company, broke his foot in the 1980s. Calling it a “sort of substitute lower leg,” the site says the knee roller can be steered with the knee, converts to a chair and can be used as a footrest when the user is seated.
The K9 orthopaedic scooter can also be seen in a 1990 issue of The Journal of Bone and Joint Surgery. The article reports the findings of a study comparing the use of crutches to the knee walker, concluding that the scooter allows patients “greater freedom on level smooth surfaces and uses less energy … and is particularly valuable in the rehabilitation of patients with ankle and foot injuries who must remain non-weight-bearing.”
Marketing the Knee Walker
In a letter to the editors published in Practical Diabetes sometime in 1994, Reid confirmed that he first made the K9 walker in 1986, but that the problem he had was with its marketing. A useful product “frequently recommended by orthopaedic surgeons,” the knee walker was nonetheless a money-losing, low-demand product. But every time Reid entertained the idea of stopping production altogether, he wrote: “There is a surge in demand and my social conscience obliges me to continue.”
The editor of the publication evidently thought so well of Reid and his K9 knee walker, for which Reid won Designer of the Year in 1993, he added a postscript to the letter, saying: “We have deviated from our normal practice by printing Mr. Reid’s full address and telephone number with his letter, in the hope that someone might come to the rescue of the K9 scooter, which we know is highly regarded by Practical Diabetes readers.”
While the K9 Orthopaedic Leg Trolley has changed very little over the years, continued innovations to steerable knee walkers have of course been made, with today’s models, like the Pathfinder Knee Walker, featuring improved steering with hand brakes, adjustable height knee pads, rubber wheels, as well as being easily collapsible and transportable.