A frequently asked question in everyday practice is whether the sound produced by knees is something to be concerned about. There are different frequencies of sounds that are emitted from the knee, such as being clicky, clunky, catching or locking.
Do you walk upstairs and hear a symphony of clicking noises coming from your knees? Do your knees noticeably click at the beginning of your run? How about during the first few steps out of bed or during squats, lunges or any other weight bearing exercise?
How can we be sure whether the sound effects are worrisome or not?
Thankfully in most cases, it is not something to be concerned about!
In an excellent review article published in Clinics of Orthopaedic Surgery, Song and colleagues divided noisy knees into 2 distinct categories:
1. Physiological (normal) noise and
2. Pathological (abnormal) noise.
As described by Song and colleagues, physiological noise is caused by ‘buildup or bursting of tiny bubbles in synovial fluid, snapping of ligaments, tendons, catching of synovium or physiological plica, hypermobile meniscus or discoid meniscus’. In contrast, pathological sources of noisy knees are caused by ‘pathological plica, patellofemoral instability, pathological snapping knee syndromes, degenerative changes such as osteophytes, cartilage and meniscal injuries as well as post-operative noise, especially after total knee arthroplasty’.
Firstly, let’s discuss some terminology that describes noisy knees:
- The term “popping” is used to describe a sudden sharp explosion and distinctly perceived sound in an injury situation. Popping can occur at the root tear of the degenerative medial meniscus and at the detachment of the cruciate or collateral ligaments of the knee.
- The term “clunking” is used to describe a loud, singular noise occurring due to release against resistance; patellofemoral clunking after total knee arthroplasty is caused by entrapment of fibrotic nodule at the junction of the superior pole of the patella and the distal quadriceps tendon within the superior aspect of the intercondylar box of the femoral component during knee flexion to extension.
- The term “clicking” is used to describe a tiny, singular noise that occurs during one cycle of knee extension and flexion; it is commonly associated with meniscal tears.
- The terms “grinding” and “grating” are used to describe a continuous scratching noise; grinding or grating is common in degenerative OA and patellofemoral pain syndrome.
The problem is we cannot associate the terminology to decide whether noisy knees are worrisome or not. The biggest delineation is that physiological knees is characterised by:
- Clicking sound effect
- Intermittent and not constant
- Absence of pain, swelling or joint effusion
Whereas pathological knees are characterized by:
- High frequent click with gradual aggravation
- Presence of swelling, effusion and pain
- Reproduced in clinical examination each time
- History of injury
So how can we manage “noisy” knees?
In most cases, physiological noisy knees can be managed by conservative care such as strengthening and stretching whereas, management of pathological noisy knees depends on the cause. Some knee pathologies can be managed conservatively whilst others must be co-managed by a knee specialist/surgeon. At the Chiro Hub, our job is to delineate between the two, reassure you and guide you to make the appropriate decision as to whether co-management and surgical opinion is necessary or conservative care alone.
After reading this article you may now be able to determine whether your “noisy” knees are physiological or pathological. If you’re still in doubt, please give the clinic a call on (02) 9317 2288 or send through an email – firstname.lastname@example.org