PEMF after Ankle Arthroscopy for ODs of the Talus.

Background:

Pulsed Electromagnetic Fields (PEMF) have been used since three decades. In animal research the effect on cartilage and bone regeneration has been proven. Clinically, however, the only entities on which an effect is objectified are delayed union or nonunion of bone fractures and knee arthroscopy; clinical results of PEMF as a solitary treatment for osteoarthritis are conflicting in different studies. In view of the working mechanism of PEMF we expect a positive effective of the treatment on osteochondral ankle defects after arthroscopic treatment.


Objective:

To achieve earlier sport resumption in more patients due to PEMFs compared to placebo.


Study design:

A double-blind, randomized, placebo controlled multicenter trial


Study population:

Active patients aged 18 years or older who receive arthroscopic treatment for an osteochondral ankle defect.


Intervention:

During 60 days after surgery patients will receive a device around the ankle (4 hrs/d) which produces electromagnetic fields or sham device.


Primary study parameters/outcome of the study:

Combination of timing of resumption of sports (weeks after surgery) and number of patients that resume sports.


Secundary study parameters/outcome of the study:

1. Work resumption;

2. AOFAS-AHS: American Orthopaedic Foot and Ankle Society;

3. Ankle Hindfoot Scale;

4. FAOS: Foot and Ankle Outcome Score;

5. Quality of life (EQ-5D);

6. Pain and satisfaction on a Visual Analogue Scale;

7. Bone regeneration on CT;

8. Side-effects.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness:

In former studies with PEMF no serious side-effects have been reported. The treatment will take place in a similar manner (frequency and duration) as in one of these studies. If a complaint or side-effect should occur, participating patients will have the opportunity to stop with the study at all times.
The treatment with PEMFs is noninvasive and is relatively simple to implement in the rehabilitation period of the current standard treatment of osteochondral defects. Patients will not feel the electromagnetic fields, nor will they hear the device, and the risk of side-effects is minimal. There will be no extra visits to the hospital. However, the visits will be longer than usual because of the assessment of research outcome (max. 30 min). Next to this, the patients will be contacted by telephone twice. The additional CT-scan involves exposure to radiation.

We hypothesize that PEMF-treatment will be of additional value after the primary arthroscopic treatment of an OD, and the resumption of sports can be both improved and accelerated.

1. Baseline (preoperative);

2. 1-2 weeks postop;

3. 1 month postop;

4. 2 months postop;

5. 6 months postop;

6. 1 year postop.

In both groups the investigational treatment (active PEMF-treatment or sham device treatment) will start three days after surgery. It will be applied four hours daily (in one or two sessions) for a period of 60 days .