August 2009

Market Mechanics: APMA Round-up

RF wound healing

Two separate studies support the use of the Provant pulsed radio frequency energy system for wound healing. Made by Scottsdale, AZ-based Regenesis Biomedical, the device transmits a fixed dose of non-ionizing, non-thermal radio frequency energy through the use of an applicator that is placed adjacent to the dressed wound. It was approved by the FDA in 1997 for the palliative treatment of postoperative pain and edema in superficial soft tissue.

A multi-center investigation led by Boston University analyzed 464 chronic lower extremity wounds that were treated with the Provant device after proving recalcitrant to other therapies.

At four weeks, at least 50% wound area reduction had been achieved in 38% of 80 diabetic foot ulcers, 42% of 80 venous stasis ulcers, 83% of 22 stage II pressure ulcers, 44% of 21 stage III pressure ulcers, and 56% of 14 stage IV pressure ulcers. Healing trajectory (change in surface area relative to treatment time) for the same wound categories was 3.9, 14.6, 5.1, 10,7, and 22.9 mm2/day.

Meanwhile, researchers from Toms River, NJ, reported on a case series of 11 wounds treated with the Provant technology for 31 to 206 days (median 82 days). Overall, an average wound closure of 87% was achieved, with six of the wounds closing completely. Healing trajectory increased 1.8 times on average compared to baseline rates.

Dermal substitute

Recently published European and Australian findings supporting the effectiveness of dermal substitute Apligraf (Organogenesis, Canton, MA) for healing diabetic foot ulcers are not significantly different from those of the 2001 American study that led to the product’s FDA approval.

Researchers from Georgetown University compared the European-Australian study, published in the March issue of the International Journal of Lower Extremity Wounds, with those of the American study, published in the May 2001 issue of Diabetes Care.

Like the individual study results, the pooled data indicated that wounds treated with Apligraf were significantly more likely to be completely healed at 12 weeks than those treated with the current standard of care (55.2% vs 34.3%). Although the two patient populations did have some demographic differences, the effect of Apligraf treatment was still significant even after controlling for location.

Dynamic splinting

The Dynasplint (Dynasplint Systems, Severna Park, MD) dynamic splinting device significantly reduced pain in 60 patients with plantar fasciitis in a four-center study. The device is designed to provide a low load, prolonged stretch with adjustable tension.

Patients were randomized to intervention or control groups. The 30 patients in the experimental group were given Dynasplint devices for nightly wear. Patients in both groups received nonsteroidal anti-inflammatory drugs, orthoses, and corticosteroid injections as needed.

After 12 weeks, patients in the experimental group reported pain levels that were significantly lower than baseline, with a mean change of 39.9 points on the 100-point Plantar Fasciopathy Pain/Disability Scale. At 12 weeks, mean pain levels for the experimental group were 32.11 points lower than for the control group, whose pain did not change significantly during the study period.

Orthotic software

Research from Des Moines University confirms that the variable-thickness foot orthoses made with Mile High Orthotics’ Delcam milling software have the desired effects of increasing stiffness and altering gait mechanics. The Commerce City, CO, orthotic lab has used OrthoModel software from Birmingham, UK-based Delcam since November 2007.

Ten subjects with no history of foot problems were analyzed under two orthotic conditions: a neutral shell orthosis, and an orthosis designed to be thicker across the arch to create a more rigid device.

In shoe pressure analysis revealed that, compared to the neutral orthosis, the variable thickness device was associated with increased resistance to arch compression (14.6 N/mm vs 8.2 N/mm) , mediolateral heel pressure (80 kPa vs 46 kPa), and impulse (89.52 N·s vs 51.93 N·s).

Optical scanning

Foot orthoses made with the Tom-Cat (Feasterville, PA) optical scanner are equivalent in shape and level of patient satisfaction to those made from traditional plaster casts, according to a study from the Temple University School of Podiatric Medicine.

Researchers used both methods to fabricate orthoses for each of 30 subjects. They found no significant differences between the scanning and casting methods with regard to orthotic length, forefoot width, midfoot width, or heel width.

The subjects wore each pair for three days, with a three-day washout period in between. Scores on a subjective questionnaire did not differ significantly for the two techniques.

One Response to Market Mechanics: APMA Round-up

  1. Pingback: Market Mechanics « Lower Extremity Review Magazine

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