Academy Meeting in Orlando
The 2002 Academy Annual Meeting was an excellent conference with a number of high quality scientific presentations, many interesting Manufacturer's Workshops, and literally dozens of new P&O products debuting in the exhibit hall. From my perspective, this was one of the strongest US meetings ever, and the enthusiasm of the attendees was palpable. This meeting was also noteworthy for the large number of colleagues from Latin America in attendance, and for the availability of simultaneous translation into Spanish of key lectures. The Academy and the APORM should be commended for collaborating in this way, and hopefully this momentum will continue in future AAOP meetings and gradually spread to other meetings as well.
Stance Control Orthoses
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One of the most remarkable things about this Academy meeting was the number of new innovations in orthotic components on display, including four different approaches to creating a Stance Control orthotic knee joint. For the first time in many years, orthotists were as excited about new ideas as the prosthetists were!
The Workshop for Horton's Stance Control Orthotic Knee Joint was clearly the "buzz" of the meeting. The room was quickly filled to capacity, so the tables were removed and more chairs added, but attendees just kept coming. Eventually the Fire Marshall said that the room couldn't hold any more people, so the remaining folks had to be turned away. This very clever approach to creating a Stance Control KAFO has been on the market since January, and interest is clearly growing quickly. Basically, Gary Horton CO has developed a cam lock that blocks flexion in early stance, but automatically releases in late stance when the normal knee extension moment occurs prior to swing phase. For additional information, including the schedule for future Qualification courses, you can visit their web site at www.stancecontrol.com.
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Horton's Technology started the momentum toward Stance Control orthoses in the US, but the major manufacturers are quickly following their lead. All of the SC orthoses from last year's Leipzig and ISPO Triennial meetings, highlighted in previous Corners, were shown at the Academy meeting. As anticipated, Fillauer was featuring a version of the Pendulum Locking Joint as a coming attraction. For more details, go to www.oandp.com/news/jmcorner
Otto Bock was showing a variation of the single sidebar UTX Swing orthosis from Holland, under the trademarked name "FreeWalk". As noted in earlier Corners, this is a Central Fabrication only concept, and the release mechanism requires some range of motion at the ankle. You can find more information about the UTX in the May 2001 Corner at www.oandp.com/news/jmcorner. The Ambroise UK site at www.ambroise-uk.com has more details, including clinical indications. Otto Bock has modified the UTX Swing to that it has a manual release in the posterior aspect of the knee joint. For more details on the FreeWalk, go to Otto Bock's site at www.ottobockus.com/products.
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Becker had a working sample of the microprocessor-controlled knee joint they have been developing over the past few years. This ambitious project, based on an original design by Jonathon Naft, CP, is much improved over the prototype in both size and function. Although no release date is set, it is expected to become commercially available later this year. The Lock/unlock signal will likely come from a thin, instrumented insole placed inside the patient's shoe or perhaps within the footplate of the AFO segment. Completion of a Training Seminar conducted at their Educational Center in Michigan will be required prior to purchasing this joint. No price estimates are available, but it seems logical that a microprocessor-controlled knee joint will be somewhat more expensive than a mechanical analog.
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Not to be outdone, Horton's Technology was showing a small add-on module that electronically triggered their Stance Control Orthotic Knee Joint as a "work in progress". Reportedly, it can be operated directly via simple footswitches or by using more sophisticated microprocessor control.
This flurry of excitement, with multiple manufacturers exploring differing approaches to creating a Stance Control orthosis, illustrates how strong the clinical interest is in these devices. Patients, physicians, and orthotists have all dreamed of the availability of a workable alternative to the traditional locked-knee KAFO. The folks at Horton's have really started some momentum with their SCOKJ, reminding me very much of our enthusiasm a few decades back when the first articulations for thermoplastic AFOs debuted. Within a few years, the collective experience of orthotists around the world resulted in articulated AFOs becoming the standard for care, and millions of patients benefited from the added mobility.
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I predict that Stance Control orthoses will follow a similar pattern; within a few years, clinicians will need to justify why they would recommend a locked knee KAFO when multiple free-motion alternatives become widely available. If you haven't kept up with this rapidly evolving aspect of orthotic rehabilitation, make a point of taking one or more of the training courses sometime this year.
Stance Flexion and Gas-Assisted Orthoses
Becker has long been a world leader in orthotic innovations, and they demonstrated their proficiency by introducing two new knee joints for KAFOs - in addition to showcasing their microprocessor-controlled knee joint development previously described. The Load Response Knee Joint is a more sophisticated design than the Trick Knee originally designed by Tim Pansiera CO from OTS, but offers similar function. Both are essentially manually locked knee joints that hold the leg in full extension during swing phase. But, an additional spring-loaded articulation allows the knee to flex slightly under weight bearing loads [as does the Total Knee and similar prosthetic devices].
Recent gait research by Steve Gard PhD has confirmed the importance of such stance phase knee flexion during normal gait, and emphasized the biomechanical importance of this motion to dissipate ground impact forces. [What determines the vertical displacement of the body during normal walking? GARD SA, CHILDRESS DS J Prosthet Orthot 2001: 13, 64-67] The Load Response Knee Joint uses a preloaded torsion spring bilaterally to control the rate of flexion. More information is available at www.beckerortho.com.
The "G-Knee" is somewhat reminiscent of Steeper's Advanced Reciprocating Gait Orthosis, which was the first KAFO to use a pressurized gas strut. The Becker design is a very compact, fairly lightweight package that functions as an offset knee joint with a powerful extension assist. It also has a manual locking option, and the gas struts are available in four different compression values offering a pretty wide range of extension assist forces.
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Like other offset joints, the G-Knee can be used [with a properly designed custom KAFO and appropriate ankle controls] to create a knee that is stabilized by Ground Reaction Forces at initial contact, yet allowed to flex during swing phase. Previous offset joint/extension assist designs have been severely limited by the small forces generated and limited durability of elastic elements. The use of pressurized gas struts will hopefully overcome these mechanical limitations and increase the applicability of free motion knee joints in KAFOs.
Friction Ankle Joint
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Last year, the Corner reported on a friction ankle joint from a Japanese company who introduces a prefabricated AFO they call the "Dream Brace"; see www.oandp.com/news/jmcorner for the earlier report. This product debuted in the US at the Academy meeting, and seemed to generate significant interest. It will be distributed in the United States by Scott Orthopedic Labs [an affiliate of Becker], and can be included in a custom AFO as well as the prefab version. Go to www.ortho-net.co.jp for more details. What makes this approach unique is that the foot remains in a fully dorsiflexed position during swing phase, while it is plantarflexed by body weight during the loading response phase of gait.
