Joint distraction in treatment of knee osteoarthritis; long-term radiographic evaluation of structural joint changes

For patients with severe knee osteoarthritis (OA), knee joint distraction (KJD)
has been proven to be clinically beneficial and cartilage tissue repair has
been demonstrated. The longest follow-up thus far has followed 20 KJD patients
from an open, uncontrolled prospective study (METC protocol 04/086) for up to 9
years, where 8 of these patients were still available for radiographic and
clinical questionnaire evaluation. Another 42 patients were treated with KJD in
two randomized controlled trials (RCTs) comparing KJD with the current
conventional treatments of total knee arthroplasty (METC protocol 10/359/E, 20
KJD patients treated) and high tibial osteotomy (METC protocol 11/072, 22 KJD
patients treated). In all patients, radiographic and clinical questionnaire
evaluation was performed up to two years. At this moment, 4 to 7 years after
treatment, 26 of the KJD patients (10 from the arthroplasty trial, 16 from the
osteotomy trial) are still followed up clinically with yearly questionnaires.
However, no radiographs have been made after two years. Since the beneficial
long-term clinical and radiographic results of the prospective study could be
measured only in a very small number of patients, we are interested to evaluate
the long-term radiographic changes in this larger group of KJD patients and how
these changes relate to their clinical follow-up. To better understand joint
changes over time, we willperform radiographs as soon as possible (which,
considering the current follow-up times, would be at 6 ± 2 years) and at the
last moment of follow-up (10 years).

To analyse long-term structural joint changes after knee joint distraction as a
treatment for knee osteoarthritis by use of radiographs

An observational study with one radiograph performed at two separate follow-up
moments.

The patients are already contacted yearly by a researcher for the
questionnaires and will now be called and asked if they would be willing to
participate in this additional research. After two weeks they will be called
again. If they are still interested in participation, they will be asked to
come to the UMCU for an appointment with the researcher, where they will be
asked to sign informed consent. In the same visit they will have the first
radiograph taken. When they reach 10 years of follow-up after KJD, they are
asked to come to the UMCU for one more radiograph.