Aquacel Surgical ® ' versus ' Mepilex Border Post on ® ' in patients with elective total knee prosthesis (TKP)

At the Department of Orthopaedics of the Spaarne Ziekenhuis annually 350
patients with gonarthrosis are operated on by means of placement of a total
knee prosthesis (TKP).
These patients are treated according to the Fast-Track protocol. The Fast-Track
clinical pathway is a multimodal, multidisciplinary concept. Patients with
total knee prosthesis will be mobilized a few hours after the operation. If
patients are mobilized quickly after surgery, the probability of complication
is even less and the will recover faster. Experience shows that the length of
the patients with total knee prosthesis is reduced by the Fast-Track protocol.

One of the risks of this surgery is a surgical site infection (SSI). To
minimize this risk we work in accordance with the national guidelines of the
Working Group Prevention(WIP) and PREZIES(prevention of hospital infections by
Surveillance). In addition to these national guidelines the Spaarne hospital
also has internal measures in place to reduce the risk of SSI. The
postoperative use of a wound drain is abolished and a pressure bandage will be
applied for 24 hours instead of 48 hours. After removing the pressure bandage
the wound is covered with a wounddressing.

Untill 2009 blisters were regularly observed around the wound after a TKP and
THP. Blisters are formed in the epidermis bordering the surgical incision of
the wound and are a major cause of discomfort, pain and postoperative morbidity
and can result in prolonged hospital stay and even infection of the prothesis
At the time ' Curapor bandage material® ' was used in combination with a
pressure bandage. To examine if the related material was an influence on the
prevalence of blistering, from november 2009 until March 2010 a comparative
study was conducted involving ' Curapor ® ' and Aquacel ®, in combination with
a foil tegaderm bandage. This investigation showed when using Aquacel ® in
combination with the tegaderm occurrence of blistering and the number of
related changes were significantly less and satisfaction of using Aquacel ®
among both patients and nurses better (not published). Following the results of
the research in september 2010 it was decided to use the Aquacel Surgical ® at
the follow-up treatment of TKP and THP operations.

The current dressing meets the clinical requirements, but has high costs. In
2007, Mepilex Border Post op ® was introduced for use in postoperative wounds.
This bandage material has also shown that it is more effective than Curapor.
Mepilex Border Post op ® is already used in prosthetics in other hospitals and
is cheaper than the Aquacel Surgical ®. However, a comparative study of the
effectiveness of these related materials has not yet taken place.
The aim of this study is to evaluate whether Mepilex Border Post op is at least
as effective as the Aquacel ® Surgical ® in terms of blistering, number of
dressing and satisfaction of both the patient and the nurse.

The primary goal of this non-inferiority study is to show that the Mepilex
Border Post op does not perform worse than the Aquacel ® Surgical ® regarding
replacing the wounddressing during hospitalization in patients with TKP.
In other words; the Mepilex Border Post op ® is just as often or less often
replaced during hospitalization compared to the Aquacel Surgical ® in patients
with elective TKP. Since there is rarely more than one exchange of the
wounddressing during hospitalization, the primary outcome measure will be how
many times the wounddressing will be replaced during hospitalization.

These non-inferiority study concerns a single-center, open-label, randomized
controlled intervention study in order to assess whether the Mepilex Border
Post op is at least equivalent to the Aquacel Surgical ® (reference treatment)
in patients with TKP.

Subjects can be randomized in one of the following two groups:
- wound dressing Aquacel Surgical or
-wound dressing Mepilex Border post op

One follow-up visit at the outpatient clinic to remove the sutures is seen as a
minimum load for the participants. This is only necessary if there is any wound
leakage at dismissal. This is a standard treatment