Association of knee crepitus with patellofemoral pain
PFP is a common joint condition affecting more women than men. Despite this, the etiology remains unclear, and no accepted examination standard exists. Diagnosis relies heavily on a thorough clinical examination, with some clinical signs usually being present in PFP, one of them being crepitus.
In this study, it was found that knee crepitus testing had high reliability for identifying women with patellofemoral pain (PFP), with women with crepitus being 4 times more likely to be in a group with PFP.
However, the presence of knee crepitus had no association with self-reported function, physical activity level, and different measures of pain (worst pain, pain when climbing stairs, and pain when squatting).
A total of 165 women with PFP and 158 pain-free women participated in the study.
The presence of knee crepitus during a 90 degree squat and stair climbing was recorded for all participants. Pain (VAS), physical activity (IPAQ), and function (AKPS) were evaluated.
Although knee crepitus was more prevalent in women with PFP, it was also found in a third of pain-free women.
Additionally, even though crepitus does not seem to influence function, physical activity level and pain, it influences patient perception, leading to negative feelings, inaccurate etiological beliefs, and restricted social participation.
The findings of this study should help educate patients about the repercussion of crepitus in their daily life.
Expert opinion by José Pedro Correia
As physiotherapists, we commonly see patients with knee pain worried about crepitus, mentioning things like "bone-on-bone grinding".
It was found that crepitus was not associated with any reason to limit function and participation in enjoyable activities for the patient.
The study also shows us that education regarding this matter can be of the utmost importance in patients with increased signs of fear-avoidance.
> From: Silva et al., Phys Ther Sports 33 (2018) 7-11 (Epub ahead of print). All rights reserved to Elsevier Ltd. Click here for the online summary.