You鈥檝e just put in a great block of training. Now your knee hurts. Does that mean you鈥檙e injured? Well鈥 it鈥檚 complicated, according to in the British Journal of Sports Medicine. Athletes are constantly dealing with pains and niggles, some that disappear and others that persist. Judging which ones to ignore and which ones to take seriously is a delicate art鈥攁nd how we choose to label those pains, it turns out, can affect the outcome.
The new article is by Morten H酶gh, a physiotherapist and pain scientist at Aalborg University in Denmark, along with colleagues from Denmark, Australia, and the United States. It argues that, in the context of sports medicine, pain and injury are two distinct entities and shouldn鈥檛 be lumped together. When pain is inappropriately labeled as an injury, H酶gh and his colleagues argue, it creates fear and anxiety and may even change how you move the affected part of the body, which can create further problems.
To start, some definitions: A sports-related injury refers to damage to some part of the body. It鈥檚 usually indicated by physical impairment, an identifiable mechanism of injury, and perhaps signs of inflammation. If you tear your ACL, there鈥檚 no doubt that you鈥檙e injured. One important caveat: If you look hard enough, you鈥檒l often find something that looks like an injury. Take X-rays of a middle-aged athlete with knee pain, and you may see signs of cartilage degeneration in the bad knee鈥攂ut you might also see the same thing in the good knee, too. That鈥檚 a common consequence of aging, and it doesn鈥檛 explain why the bad knee is hurting.
Pain, on the other hand, is defined in the paper as 鈥渁n unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage.鈥 The italics are mine. It certainly feels like something is damaged. But pain is fundamentally a subjective, patient-reported phenomenon, and it can exist even without an identifiable injury. One of the examples in the paper is patellofemoral pain, which is a very common diagnosis in runners that basically means your knee hurts but they can鈥檛 figure out exactly why it鈥檚 hurting. In comparison, patella tendinopathy is knee pain with a clinically identifiable cause for the pain (a damaged or inflamed tendon).
The paper includes an infographic (viewable ) that outlines the differences between what they call 鈥渟ports-related injuries鈥 and 鈥渟ports-related pain.鈥 Here are some of the key points:
- Pain is influenced by 鈥渃ontext, expectations, beliefs, and cognitions鈥; injuries aren鈥檛. As it happens, the New York Times ran just last week on how words like 鈥渂urning鈥 and 鈥渟tabbing鈥 affect how you feel pain. My favorite nugget from that story: the patient in Australia who returned to her native Nepal for treatment because no one understood her description of 鈥渒at-kat,鈥 an untranslatable expression of achiness that can feel deeply cold.
- Injuries are objectively observable; pain isn鈥檛. That said, subjective assessments of pain, including a simple zero to ten rating, can be remarkably repeatable and informative. That鈥檚 how we know that effort, not pain, is what causes people to give up in tests of cycling endurance.
- The prognosis for an injury will depend on which body part is affected: injured muscles heal better than, say, spinal disks, and the healing will proceed in predictable stages. Pain, in contrast, often comes and goes unpredictably, and its severity doesn鈥檛 necessarily depend on the healing stage.
- The fundamental principle of rehab from injury is gradually increasing the load on the damaged tissue until healing is complete and it鈥檚 capable of handling the demands of training and competition. The focus for sports-related pain is improving the patient鈥檚 ability to manage the pain, for example by avoiding negative responses like pain catastrophizing that make it feel worse. This process isn鈥檛 as linear as rehabbing damaged tissue: you can鈥檛 just gradually increase training load and assume that pain will go away.
The themes in H酶gh鈥檚 paper overlap with , this one from Australian physician Daniel Friedman and his colleagues, on the dangers of diagnostic labels. Calling a knee injury a meniscal tear rather than a meniscal strain, for example, might toward opting for arthroscopic surgery, even though that鈥檚 not considered the best approach to that injury. More generally, Friedman writes, the words chosen to describe injuries 鈥渕ay catalyze a looping effect of catastrophization, anxiety, and fear of movement.鈥
In many cases, of course, these nuances aren鈥檛 a big deal. If you get a stress fracture, it will hurt. You鈥檒l have to rest it until it heals, gradually increase the load on it, and then pain should no longer be an issue. The injury and its associated pain are tightly coupled. But other cases aren鈥檛 so straightforward. For people with chronic Achilles pain, there鈥檚 often no clear link between the physical state of the tendon and how it feels, so reducing and managing pain sufficiently to return to training is a more useful goal than waiting for the tendon to be 鈥渉ealed.鈥 Figuring out where any given flare-up falls on that spectrum is tricky, but the first step, according to H酶gh, is simply recognizing that sometimes pain is just pain.
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