J. Martin Carlson, CPO


1972, Marty Carlson was an aeronautical engineer looking for a new career. He hoped that P&O might be a field where he could use his background to help people more directly, than by designing widgets for a successful engineering firm as he was currently doing. Fortuitously, the local practitioners he visited directed him to the local children's hospital, and they encouraged him to complete the additional training necessary to become an ABC Certified practitioner. The rest is history....

I have known and admired Marty Carlson for many years. As a novice, I distinctly remember reading the 1979 paper on foot orthoses he co-authored with Gene Berglund CO, undoubtedly one of the most widely quoted publications in the pedorthic, podiatric, and orthotic literature. By clearly illustrating basic engineering principles that can be applied to provide biomechanical control of the foot and ankle, this landmark article elevated the standard for the design of foot orthoses from purely subjective theories to rational science.


In particular, their detailed explanation of how a foot orthosis functions mechanically made it easy to predict when a given approach would be successful for a specific biomechanical deficit, eliminating much of the trial and error that was previously inherent in this realm. The clear and concise vector diagrams made it clear why a "little lump of plastic" strategically placed on the medial border of the orthosis had such a profound effect in reducing ankle instability: this was physics and not hyperbole.

Most of us can work a lifetime and never realize such important insights. But, this article was just one of many contributions to our profession involving Marty Carlson and his colleagues. Reread the entire article. By the way, the original article misspelled Marty's last name as "Colson", so it was years later before I realized that the Marty Carlson I knew was the senior author of this paper!

Marty was the head of the P&O department at Gillette Children's Hospital in St. Paul, Minnesota during the 70s and 80s. During this period, he and his staff followed hundreds of patients with idiopathic scoliosis and monitored them closely along with the other members of the hospital staff. Based on this experience, John Lonstein MD and Marty co-authored one of the landmark papers on the natural history of this disorder in 1984. This publication remains one of the pivotal studies about this disease process that helped define much more clearly when an orthosis was indicated and, equally importantly, when an orthosis was unnecessary.

Prior to this article, physicians commonly prescribed orthoses for patients with relatively small curves, and were very complimentary when the orthoses we fitted "succeeded in preventing progression". On the other hand, orthotists were also frequently chastised when our best effort failed to stop massive curves from increasing in magnitude. Lonstein and Carlson's research showed convincingly that smaller curves often did not progress much regardless of treatment, while beyond a certain magnitude no orthosis was ever effective. This led to much more effective treatment, both in surgical and orthotic terms, sparing thousands of patients from ineffective treatment. Read about The prediction of curve progression in untreated idiopathic scoliosis during growth.

During this period, Marty and colleagues, including Mark Payette CO, also developed and promulgated the Gillette Sitting Orthosis. This was one of the first applications of an orthosis to provide biomechanical support for non-ambulatory purposes, and this approach has proven to be quite effective for children and adults with cerebral palsy, muscular dystrophy and similar pathologies. Read about The "Gillette" sitting support orthosis.

Since that time, Marty has maintained an active interest in orthotic seating and has been one of the most vocal advocates for the development of prefabricated systems for selected applications. He is also a staunch advocate for multidisciplinary treatment teams, and in 1986 he and colleagues Lonstein, Beck, and Wilkie published Seating for children and young adults with cerebral palsy.

In 1989, Marty was senior author of a paper with John French demonstrating that the length of the lever arms and their rigidity were key determinants in the effectiveness of knee orthoses intended to treat genu varum or valgum. Subsequent studies have corroborated this perspective, and have thereby helped countless patients avoid the frustration of receiving an ineffective prefab orthosis. Conducting these experiments and reporting the objective results was far more effective in educating prescribers and discouraging the use of biomechanically inappropriate orthoses than the ubiquitous whining that "unqualified people are misapplying knee orthoses" that was the typical response of other orthotists at that time. Marty saw the same problem we all did, but he and his collaborators found an effective way to combat the problem, and added credibility to the field at the same time. Read about Knee orthoses for valgus protection: experiments on 11 designs with related analyses of orthosis length and rigidity.

About ten years ago, Marty left Gillette and opened a private practice: Tamarack Habilitation. In 1991, Marty, Fran Hollerbach, and Bruce Day reported on their successful experiences creating a lace-up orthosis to unweight the distal tibia, hindfoot, and midfoot, offering an effective alternative to the ubiquitous "PTB" orthosis. Read aboutA calf corset weightbearing ankle-foot orthosis design-(At the Acadamy's JPO Library).

In 1995, Marty and Mark Payette CO published an outstanding article based on many years of experience successfully managing recurrent ulcerations. Read about Seating orthosis design for prevention of decubitus ulcers-(At the Acadamy's JPO Library) and learn more about the basic biomechanical factors involved.

In 1998, Marty and Susan Wood published an important contribution to prosthetic design describing a very clever approach to creating a volume-adjustable socket for patients with bilateral hip disarticulation or transpelvic amputations. Read about A flexible, air-permeable socket prosthesis for bilateral hip disarticulation and hemicorporectomy amputees-(At the Acadamy's JPO Library), which is based on their extensive experience in the management of such very difficult and rare cases.

Abstracts from the RECAL database at the University of Strathclyde listing all of Marty Carlson's publications

In addition to all his contributions as a clinician, researcher, and author, Marty has also developed a number of successful components and products over the years. Recently, Marty sold his clinical practice to focus all of his attention on developing additional innovative solutions for prosthetic and orthotic challenges.

His best-known product is an improvement on the double flexure orthotic joints-(At the Acadamy's JPO Library) developed with Bruce Day and Gene Berglund at Gillette Children's Hospital in the 1980s, known colloquially as "gummy bears". These flexible polyurethane rods are most often used as ankle articulations, although they work well for many other applications. These apparently simple parts are actually extremely well conceived and engineered, which is why they are modest in cost, simple to use, and self-aligning.

A few years ago, Marty began producing an improved version of these joints that were much more resistant to elongation, and could also be used to resist or assist motion. These Tamarack joints are now in use worldwide, and have proven successful for managing a broad range of clinical problems.

It's not difficult for engineers to find complicated and costly solutions to mechanical problems. But, particularly in orthotic rehabilitation, it is often very difficult to find sufficient funding for expensive components. For the patients we care for, reasonable cost solutions are critical for widespread acceptance, and Marty Carlson seems to have the creativity to identify and develop such practical solutions.

Last year, Tamarack introduced yet another low cost addition to our armamentarium: ShearBan. This Teflon-coated self-adhesive material can be retro-fitted to almost any orthosis or prosthesis to reduce shear stress on the skin in strategic areas, and has been well received among clinicians.

A few months ago, I attended an open house to celebrate Tamarack's ten-year anniversary, where they announced the availability of a deep-throat hydraulic punch specifically designed for orthotic laboratory. It is good to see the pace of innovation stepped up now that Marty can work full-time on new products, and given his track record thus far, we can all look forward to a number of useful clinical innovations in the coming years.

While I was at the Tamarack open house, I spotted a very interesting poster presentation highlighting the history of their orthotic developments. It is reproduced with permission of the graphic artist who created it, Marty's nephew Jon Carlson.

Although it will take a while to download due to the size of the file, I encourage readers to take the time to do so and to read it thoroughly. It is a remarkable saga of the continuing contributions to clinical practice that Marty has been associated with over the past thirty years, and it is a testimony to the difference that dedicated practitioners can make for the patients we serve.

Anyone feeling discouraged by today's cost containment climate will be particularly interested in the description of the lawsuit against the Minnesota Department of Human Services that Marty initiated, along with local disability advocates, after the State repeatedly refused to provide custom seating orthoses to children who clearly needed them. In contrast to DHS retaliatory threats to cut off all payments to Marty's facility, when the smoke had cleared, the Attorney General supported the plaintiffs and such services are now funded at Gillette Children's Hospital as well.



Return to January 2001 Corner

Next Article