Orthofix AccelStim Manual De Instrucciones página 31

Netherlands, were submitted to the FDA as the basis for approval of the EXOGEN
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Bone Healing System to treat established nonunions. The studies had a self-paired
control design with each nonunion case serving as its own control, and with the prior
treatment result of failed orthopedic care as the control compared to ultrasound as
the only new treatment. The criterion for the definition of nonunion cases was the
minimum time from fracture of nine months. The primary efficacy outcome was
healed due to EXOGEN treatment, as judged clinically (no pain upon palpation or
weightbearing) and radiographically (3 out of 4 cortices bridged).
Clinical Results
Analyzing the data from Germany, the completed cases had a healed rate of 86%
(64/74) with a mean time to a healed fracture of 163±9.4 days. The median heal time
was 142 days with a range of 53 to 375 days. The mean fracture age for the healed
cases was 494 days with a range of 257-6011 days. The scaphoid nonunion heal
rate of 33% (2/6) was attributable to the three scaphoid nonunion failures that were all
more than 10 years in fracture age and, therefore, were very difficult and challenging
cases. Cases with metal surgical fixation present during EXOGEN treatment such as
those with ORIF (Open Reduction Internal Fixation) and those cases with intramedullary
rods had an 88% (21/24) and 100% (16/16) healed rate, respectively. The results of this
nonunion paired design clinical study established the safety and efficacy of the EXOGEN
Bone Healing System in treating nonunions. This includes cases that had long fracture
ages of up to five years but suggests that nonunions with of over five years duration
may have a decreased response to ultrasound treatment. The results are summarized
in Table 1.
Nolte et al., reporting on the Netherlands study, confirmed the 86% (25/29) success
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rate and showed the average heal time to be around five months without additional
intervention. Average nonunion fracture age was 61 weeks. There were high success
rates seen with atrophic and oligotrophic non-unions (80% and 92% respectively)
where some biological deficiency may contribute to the original nonunion. Additionally
the application of EXOGEN to hypertrophic nonunions, which might usually be
considered as requiring revised treatment to correct fracture instability, was successful
in 80% of cases. Success was seen for a range of bones, all types of typical primary
fracture management, and across all patient age ranges. For the United States study,
the completed cases group had an 82% (352/429) heal rate.
Other Nonunion Studies
Frankel and Mizuno in their analysis of the 1,546 USA patient nonunion registry
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demonstrated that for patients with risk factors that may impair fracture healing,
such as alcoholism, smoking, diabetes, vascular problems, or steroid use, there was
no significant change in the effectiveness of the EXOGEN Bone Healing System.High
success rates were achieved for all bones, regardless of fracture age, but there was a
trend towards higher success rates and faster healing with earlier intervention.
Strauss and Gonya described the effects of low-intensity pulsed ultrasound on two
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difficult cases of Charcot nonunions with multiple prior failed surgical procedures. Both
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