If you’ve ever looked into knee replacement surgery, you may have come across the term “knee score”.
If you haven’t, well, it probably sounds a bit perplexing – like some kind of obscure goalscoring technique for a sport you’ve never heard of… But in fact knee scores are quite commonplace in orthopaedics and, if you are in line for a major knee operation, you’re very likely to be asked to fill one out. (There’s the first clue.)
So… what is a knee score?
In a nutshell, a knee score is a questionnaire-based tool for evaluating pain and function in your knee joint. Being a score, it can rise or fall each time you complete it. This means it acts as a measure of how well a knee is faring, particularly before and after an operation. There are several different types and versions of knee scores. Some are completed by specialists and surgeons, but the most commonly-used one – the Oxford Knee Score (OKS) – is based on answers from patients. The OKS was originally created for total knee replacements patients, but it’s now used to assess other treatments too.
How does the scoring work?
The Oxford score features 12 questions, with five possible answers in each case. Some of the questions focus on pain. For example: “how would you describe the pain you usually have from your knee?”, with answers ranging from “None” to “Severe”. Other questions focus on function. For instance: “Could you walk down one flight of stairs?” or “Could you do the household shopping on your own?”, where the answers range from “Yes, easily” to “No, impossible”. Each answer is scored from 0 to 4 (zero is the worst outcome, 4 the best). You then tot up these figures to get an overall total. The best possible total score would be 48.*
Why are knee scores useful?
They can be helpful in a number of ways. Firstly, they provide a baseline for how bad your knee is before surgery. Once you’ve had your surgery, we can use that baseline to track your progress – and in most cases the score should rise as you recover. This is a helpful metric for surgeons as they monitor your new joint, and for you as you look back on your recovery journey and, hopefully, see the progress you’ve made. On a broader level, knee scores help the healthcare industry to monitor new implants and techniques, and identify any trends that might indicate a problem.
What are their limitations?
Knee scores are very individual. For example, one person’s “moderate” knee pain could feel quite severe to someone else. Equally, their struggles with the shopping might be more to do with a bad back than a painful knee – yet the score wouldn’t reflect that. In other words, it’s a personal perspective, not a scientific measurement. That’s why it can be unhelpful to jump to sweeping conclusions about your overall score total. Just because a person has a low score doesn’t mean they must absolutely have a total knee replacement. There’s also the question of expectations. While a 100-year-old might be quite satisfied to be moving up and downstairs better than they were before, that outcome is unlikely to cut ice with a much younger patient who’s desperate to get back to hiking and golfing. So there’s a balance to be struck. But as a general indicator for your progress after surgery? Knee scores can be very helpful. If you’re interested in seeing what one looks like up close, scroll down to the resources list below…
*Confusingly, the OKS originally used a different scoring system, where the best outcome was a low total and vice versa. So if you ever find yourself looking at older studies and articles, it’s worth checking which scoring method was used.
An example Knee Score questionnaire (from the Shrewsbury and Telford Hospital NHS Trust)
Three key online resources to help you feel confident about replacement surgery