Effect of cryo- and compression therapy after Total Knee and Unicompartmental Arthroplasty, A Randomised Controlled Trial*

Total and unicompartmental knee arthroplasty (TKA/UKA) are widely accepted and
effective treatment options for end-stage osteoarthritis (OA) of the knee.
Significant long-term improvement in pain, function and quality of life after
TKA are reported in literature, yet rehabilitation in the first three months
remains challenging.Pain and swelling due to inflammatory reaction after tissue
damage may obstruct effective rehabilitation in the early postoperative period.
This could result in stiffness of the knee and patient dissatisfaction, also in
the long-term. Differences in the rehabilitation have been found between UKA
and TKA patients, where UKA patients have less postoperative complications, a
better and faster recovery after surgery, and less pain and opioid use that may
be explained by the less invasive nature of the UKA surgery. Despite
encouraging results after implementing rapid recovery protocols with
perioperative local infiltration analgesia and early mobilisation, treatment
after both treatments could still be optimised. In general, opioid use is
common in the early postoperative period after a TKA and - to a lesser extend -
an UKA. Negative side effects (e.g., nausea, vomiting, dizziness) and the
increasing abuse of opioid analgesics in modern society drives the search for
alternative analgesic techniques. Cryotherapy could play a role in optimising
rehabilitation after surgery. Cryotherapy involves the application of cold to
the skin surrounding injured soft tissue. Application of cold reduces local
blood flow due to vasoconstriction and ensuing the local inflammatory reaction,
swelling and heat experience.

The effectiveness of cryotherapy on the recovery after surgery was studied in
numerous studies in mainly TKA patients and in the majority - but not in all -
of these studies a beneficial effect of the cold therapy was found. Adie et al
(2010) show in a systematic review and meta-analysis based on 11 RCT*s that
using cryotherapy the blood loss is significant lower and the range of motion
is higher at discharge. In addition, a small effect on pain is found,
cryotherapy leads to lower levels of pain at day 2. This effect was not found
at day 1 and 3. No differences were found in complications, analgesics use,
length of stay and swelling. Functioning was only measured in one study, so no
conclusions could be drawn about that variable. These authors concluded that
using cryotherapy postoperatively after a TKA might have benefits, but that the
clinical relevance was uncertain. A more recent review performed by Ni et al
(2015) confirmed, based on 12 studies, the beneficial results concerning blood
loss and pain reduction on day 2. Also, no complications were documented
related to the cryotherapy.

Sadoghi et al. (2018) focused on the effects of cryotherapy starting in the
first postoperative week and found significant beneficial effects on pain on
day 2 and knee flexion on day 6.6 They did not evidence significant effects in
use of analgesics. By contrast, Thijs et al. (2019) found that patients in the
cryotherapy group used 2.6 times less opioids as an escape medication during
the first four postoperative days compared to the control group. Although they
found a significant reduction in NRS pain scores before and after cooling in
the cryotherapy group, no clear differences on pain between the two groups in
the first postoperative week were found. In the long-term too - 2, 6 and 12
weeks postoperatively - no differences could be evidenced. Our recently
published RCT has shown that computer-assisted cryotherapy during the first
postoperative week following TKA has beneficial in terms of pain reduction and
diminished opioid consumption during this first week. At 6 weeks no differences
in pain were found. Also the physical examination tests - aROM, knee
circumference and Timed Up and Go - showed no difference between groups after 6
weeks. A period of only one week cooling postoperatively can be a reason for
short term beneficial effect of the cryotherapy. To our knowledge, no study has
been conducted on the effects of 6 weeks cryo and compression therapy after a
TKA and UKA.

There are several ways to apply cryotherapy, using ice or cold packs, or
mechanical devices which create a standardized cooling treatment of the injured
tissue, with and without compression. A review of the currently available
literature in TKA patients (14 studies) and UKA patients (2 studies) stated
that standardized continuous cold flow with compression was associated with
better outcomes. However, since the financial aspect is also a major element in
patient care, cost-effectiveness must be considered as well. Cost benefit
analyses demonstrated that simpler devices as ice bag compression bandages or
cold packs are far less costly, with no disadvantage in outcomes in several
studies This makes that in the current study an easy-to-use brace with an
inserted cold pack, that can be applied with a close fit to the knee, with
optional application of manual compression will be used. The combination of
cold and compression was suggested to result in longer and improved anaesthetic
effect after application.

Primary objective:
Investigating the effect of the use of cryo- and compression therapy during the
first 6 postoperative weeks after surgery (TKA en UKA) on the perceived pain in
rest at 6 weeks postoperative.

Secundary objectives:
Investigating the effect of the use of cryo- and compression therapy during the
first 6 postoperative weeks after TKA/UKA surgery on pain in rest and while
loading/during activity, oioid use, during the first 6 weeks, functioning,
patient satisfaction, general health. Considering the differences in the
rehabilitation between the patient groups (TKA and UKA), potential differences
in effectiveness of the cryo- and compression intervention between both patient
groups (UKA and TKA) on these outcome measures will be studied as well. Also
the compliance will be monitored as a secundary outcome.

A single-centre single-blinded randomized controlled trial, executed in TKA and
UKA patients.

For the cryo and compression therapy the U-sport Ultimate Recover Knee cold
compression brace
(https://www.u-sport.com/producten/medical-care/ultimate-recover-knee/) will be
used. This brace combines cold and compression therapy using a reusable gel
package and an adjustable hand pump, which is an easy-to-use. Cryo and
compression therapy will be administered during the first 6 postoperative
weeks, starting after discharge. Because of practical reasons, no cryo- and
compression therapy will be administered during admission. Patients will be
instructed to use the brace 5 times a day for a maximum of 20 minutes, and will
be advised to apply compression (amount of compression based on their own
preference).The control group will receive standard post-operative treatment
according to local rapid recovery rehabilitation program without the use of
cryo and compression therapy. (Additional) use of a cold pack which is part of
standard care is allowed in both groups.

Several studies have shown beneficial effects of 1 week of cryo- and
compression therapy after TKA on pain reduction and diminished analgesic use in
the first post-operative week. It is currently unknown what the effect of 6
weeks of cryo- and compression therapy will be on TKA/UKA rehabilitation.
Possible benefits of this study are effective postoperative pain control,
diminished use of opioid analgesic, improving functional outcome and patient
satisfaction after TKA/UKA. Potential risks of cryotherapy are local
hypothermia of the skin resulting in frostbite, necrosis and thrombosis.
However, based on the current literature, these side effects were not reported
in the studies using cryo- and compression therapy. To nullify these risks in
our study, patients are instructed to wear the brace for a maximum of 20
minutes per cry-and compression session. In addition, patients are advised to
put a piece of fabric cloth between the brace and the skin. We believe this
makes the risks neglectable.