Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT01785264 |
Other study ID # |
2012/530/REK |
Secondary ID |
2013005 |
Status |
Completed |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
February 2013 |
Est. completion date |
May 31, 2019 |
Study information
Verified date |
April 2021 |
Source |
University Hospital, Akershus |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
To compare the end-results of three different methods of treatment of acute achilles tendon
ruptures, it is necessary to establish identical rehabilitation protocols. Traditionally,
early mobilization has been reserved for patients treated surgically and this may have
unintentionally skewed treatment results. The investigators have therefore designed a
prospective randomized trial performed as collaboration between Akershus University Hospital
(Ahus), Oslo University Hospital (The Emergency Department), Østfold Hospital (Fredrikstad)
and Drammen Hospital. The four institutions were chosen because of their geographical
proximity and because they jointly have a substantial catchment area. Treatment is divided
into three arms, and patients between 18 and 60 years of age sustaining first time achilles
tendon ruptures will be invited to participate.
Description:
Patients are randomized to either surgery or non-operative treatment. Surgery will be
performed by open technique or by using a mini-invasive approach. Open surgery remains
widespread and arguably the best documented treatment, however mini-invasive surgery is also
included because of its potential to lessen the risk of wound complications. Michael Amlang
and Hans Zwipp at the University of Dresden represent some of the leading foot- and ankle
surgeons in Europe. They and their co-workers have developed a protocol for mini-invasive
surgery using specially adapted proprietary instruments. Michael Amlang visited Ahus in 2012
teaching the general principles of the Dresden mini-invasive treatment. To ensure optimal and
reproducible results, surgeons participating in the study must master both techniques.
All patients included in the study will be immobilized in equinus position for the first two
weeks using a below-the-knee cast. Following the first two weeks the cast is replaced with a
brace maintaining ∼12° plantar flexion (three heel lifts). We have chosen to use standardized
heel lifts because it eases weightbearing compared to a hinged brace. After two weeks (four
weeks from injury) the ankle position is adjusted to ∼8° plantar flexion (two heel lifts) and
following additional two weeks the ankle position is adjusted to ∼4° plantar flexion (one
heel lift). The last week of the orthosis treatment the heel lift is completely removed.
Hence, the brace is retained for a total of six weeks, and patients are allowed full weight
bearing as tolerated during the entire time period. The brace is worn day and night for the
first two weeks, but is removed during nighttime for the last four weeks. Importantly, the
immobilization regimen is identical for all three-treatment groups. To ensure identical
rehabilitation following immobilization, physical therapy has to adhere to a standardized
protocol supervised by an experienced physiotherapist at the Norwegian Sport Medicine Clinic
(NIMI).
The defined endpoint is treatment results evaluated by the Achilles tendon Total Rupture
Score (ATRS). This is a patient-centered self-reporting instrument with good reliability,
validity and sensitivity. Furthermore, ATRS will be combined with SF36, another commonly used
self-reporting instrument. Pain is evaluated by a visual analogue scale (VAS). Functional
results are evaluated by The MuscleLab measurement system (Ergotest Innovation, Porsgrunn,
Norway). The system consists of two different jump tests (drop counter-movement jump and
hopping), two different strength tests (concentric heel rise and eccentric-concentric heel
rise) and one muscular endurance test (standing heel rise) and the system has been shown to
be both valid and reliable assessing lower leg function in patients with Achilles
tendinopathy. We will also measure dorsiflexion and plantarflexion range of movement (ROM) as
well as the circumference of the calf, all widely used endpoints in similar studies.
Secondly, we want to compare the risk of complications such as infections and reruptures. The
patients are examined at baseline and after 6 and 12 months. Since there are only minor
functional improvements after 12 months, we do not plan any later follow-up as part of the
main project. The 6 and 12 months examinations will be completed at the Norwegian Sport
Medicine Clinic (NIMI), these examinations are blinded and performed by two physiotherapists
who have not been taking part in the study prior to final follow-up. Patients will be wearing
knee socks to hide potential scar tissue.
Although the minimum clinically important difference in ATRS score has yet to be determined,
Carmont and coworkers have shown that 7 points represent the smallest detectable change.
Moreover, a study by Metz et al. found that patients with reruptures of the achilles tendon
presented on average 18 points lower scores whereas patients with injuries of the sural nerve
or superficial wound infections presented scores 10 and 9 points lower than average,
respectively. In order to detect a difference of 7 points in ATRS score with 80% power there
must be 160 patients in each group. Power calculations are based on one-way ANOVA analyses
assuming a common standard deviation of 20. This concomitantly allows us to detect
differences as low as 8 % with respect to complications. This is of pivotal importance since
assessing the risk of reruptures is essential when establishing treatment recommendations. We
therefore plan to include a total of 530 patients allowing for expected loss during
follow-up. Ahus, The Emergency Department of Oslo University Hospital, Drammen and
Fredrikstad Hospitals have a catchment area of nearly 1.3 million people and treats in excess
of 300 achilles tendon ruptures annually. This allows for completion of the inclusion period
within three years. In our view, this is the first study to include a sufficient number of
patients to detect lesser, but yet important differences, and the results will be published
in a suitable international peer-reviewed journal.
The prospective randomized trial embodies many different disciplines and will spur off
follow-up studies. As part of the main project we will conduct a treatment-cost analysis in
relation to individual results. We will also perform an investigation based on ultrasound
grading of Achilles tendon ruptures according to a classification system established by
Michael Amlang and colleagues. Previous studies have provided evidence suggesting that
treatment results may depend on the extension of the injury, and that treatment
recommendations should be based on type of rupture sustained. This is of particular interest
as it may facilitate individualized treatment. Together with the prospective randomized trial
and the treatment-cost analysis, the ultrasound investigation will constitute the core of the
Doctor of Philosophy (PhD) project.