If PFP, don’t wait-and-see
There are many reasons why I spend so much of my time on Patellofemoral Pain (we’ll call it PFP from here). It’s super common; if you are military personnel in basic training, or an active adolescent (arguably significantly different phenotypes), you’ve a 1/10 chance of developing PFP in your lifetime8. Recreational runner? You’ve a 6/100 chance9. The annual prevalence of PFP in the general population is as high as 23%10. Either way, if you’re a clinician working in musculoskeletal medicine, chances are you’ll see a lot of PFP (unless you don’t do knees, in which case, maybe stop reading).
No different to other gradual onset musculoskeletal conditions, PFP has a negative influence on those experiencing it. People with PFP are six-times more likely to be anxious and/or depressed11, and are 40% less physically active3, than population norms. Some recent qualitative work from our research group really drives this home1, with one participant stating:
“It’s not just treating the knee pain, it’s treating the social issues, the depression”
But the main reason I spend so much of my time on PFP is that it’s generally treated rather poorly. I often hear that PFP is like non-specific low back pain of the knee. I disagree; acute, non-specific low back pain (i.e., in the absence of neurogenic leg pain or serious pathology) broadly has a positive natural history vastly different to that of PFP. There is still the persisting myth that PFP is a self-limiting condition, and that people should recover within three-months. But over 50% of people with PFP are still in pain over five-years after their initial diagnosis5. We know that the longer a patient’s symptom duration, the poorer their overall prognosis4,6. Considered together, this suggests an overt mismatch in the advice being given to patients relative to our understanding of aetiology and prognosis. I have long said to patients with tendinopathy: “this will get better in months rather than weeks, sometimes years rather than months”. I’m ever more convinced that the same advice is true for PFP.