Well, cabbages for knee osteoarthritis, anyway! In this interesting study, three approaches to managing knee pain from moderate osteoarthritis were put to the test. To be truthful, actually only two active treatments were compared – the third was “usual care”.
In a carefully conducted trial, where participants were randomly allocated to one of three groups, and the study organiser remained blinded to which group people were allocated, topical diclofenac gel, usual care or a cabbage leaf compress were applied over the course of four weeks. Key outcomes were pain intensity and scores on the WOMAC, a common measure of the impact of osteoarthritis on daily life.
Participants were asked to rate their expectations on whether cabbage leaf or the gel would be successful in improving knee pain prior to the study commencing. Each person in the cabbage leaf group was asked to take one or two cabbage leaves, remove the hard stem, bruise the leaves, then wrap them around the knee with a bandage and leave for at least two hours, preferably overnight. In the gel group, participants were asked to rub the gel over the knee up to 4 times a day. In the treatment as usual group, participants were asked to continue with their usual routine and care, but not to begin any new treatments over the period of time.
What did they find?
Well, as a breastfeeding mother I well remember the pain of engorged breasts – and the relief I got from cabbage leaves (although I will never forgive the man who brought two half cabbages home, held them up in front of me and said “I think they’ll just about fit”!). I wondered if the same effect might have been experienced by participants in this study – and to a certain extent, yes! While the effect sizes were not large, a significant group difference was found between cabbage leaf wrap and usual care (difference, -12.1; 95% CI, -23.1,-1.0; P=0.033) after 4 weeks. No group difference was found between cabbage leaf wrap and gel (difference, -8.6; 95% CI, -21.5, 4.4; P=0.190).
A small but consistent decline in pain intensity was found in the cabbage leaf wrap and gel groups, but not in the usual care group over the four weeks of the study.
This trial found that a 4-week application of cabbage leaf wraps was more effective than usual with respect to pain, functional disability, and quality of life. It was, however, not superior to a 4-week application of topical medication. Patients were satisfied with both interventions, and except for 2 adverse events in both groups the applications were well accepted and tolerated.
What does this mean?
Well, for me this study shows that a simple, home remedy may provide some help for people who either can’t afford the cost of gel, or who don’t want to take a medication. This treatment truly is “natural”! The study design doesn’t allow us to conclude that cabbage leaf wraps are better than gel, or that it was the cabbage leaf itself that made a difference (participants and physicians had to know what was being administered because it’s fairly hard to hide a cabbage leaf!), so the results could be due to “meaning response” or placebo. And the pain reduction was very small – but nonetheless important to the participants.
What’s cool for me is that this is something people can choose to do for themselves. It doesn’t seem to have adverse effects (those reported in the study could be unrelated to the cabbage), and people find it relatively easy to use. Given the cost of pharmaceuticals, and the need to attend a doctor to get a prescription, to know there is a reasonable alternative (or even adjunct) seems useful.
Lauche, Romy, Romeikat, Nadine, Cramer, Holger, Al-Abtah, Jallal, Dobos, Gustav, & Saha, Felix J. (2016). Efficacy of Cabbage Leaf Wraps in the Treatment of Symptomatic Osteoarthritis of the Knee: A Randomized Controlled Trial. The Clinical journal of pain. (in press)