Updated June 2019
When our knees hurt, we let people know. However, do you ever wonder what’s exactly going on in and around your knees? With so many joints, muscles, bones, and more – it’s a complex part of the body. And when preventing knee injuries, knowing the exact intricacies of our knees can be overwhelming.
Here’s a simple guide to help introduce you to a pair of your biggest supporters: your knees.
Patellofemoral Joint Anatomy
Two important joints that make up the knee include:
Tibiofemoral joint (where our femur meets our tibia/shin bone)
Patellofemoral joint (where our patella meets our femur)
The patella itself functions increase the efficiency of the quadriceps muscles by increasing the angle of pull through the patellar tendon as it travels overtop of the knee and down to its insertion in the tibia/shin bone.
During the bending and straightening of the knee, the patella (knee cap) glides along a groove at the end of the femur. This gliding is normally very smooth due to the cartilage on each surface.
The following images display the movement of the patella along the femur as the knee bends:
Patellofemoral Pain Syndrome (PFPS)
PFPS usually presents as pain under the knee cap. It can occur in one or both knees. This pain is often worse with the following activities:
Walking down stairs
Sitting for long periods of time (e.g., going to the theatre)
Causes of PFPS
Multiple factors can contribute to patellofemoral pain:
Poor biomechanics or alignment
Muscle weakness or imbalance
These factors can influence the alignment of the patella in the femoral groove, causing pain due
to the change in tracking movement at the knee bends and straightens.
For some individuals, the patella may be positioned slightly differently due to anatomical differences, which can lead to muscle imbalances.
For others, it may be that a muscular imbalance leads to abnormal movement of the patella while bending and straightening the knee (e.g., if the outer quadriceps are weaker than the inner quadriceps, the patella is pulled too far to the outside surface of the condyles of the femur during activity).
The following video further explains the anatomy and causes of patellofemoral pain: https://www.youtube.com/watch?v=l2Mg0qursmc
Preventing Knee Injuries and Treatment Options for PFPS
Assessment. From a physiotherapist, to determine the contributing, or potential contributing factor(s).
Rest/pacing. Depending on the severity of knee pain, decreasing training frequency or distance, or by avoiding other aggravating activities like squatting or walking downhill, the inflammation can have a chance to settle. Once symptoms have settled, it is important to gradually increase activity again.
Ice. Following activity can also help reduce inflammation and pain.
Specific taping techniques. Can provide temporary relief for some individuals, as they can help correct the position of the patella. To read more on therapeutic taping of PFPS and other common injuries, refer to the following blog: https://www.royalcityphysio.com/single-post/2018/04/26/5-Common-Injuries-that-May-Respond-Well-to-Athletic-Taping
Biomechanics. Alignment during movement/activity will likely be an important treatment avenue (e.g., ensuring that the knee stays in line with toes, and that the pelvis stays level during a single like knee bend).
Strengthening. Particularly of the quadricep and gluteal muscles.
Stretching. Particularly the quadriceps, IT band, hamstring, and calf muscles.
For some more great information on PFPS, check out this article from the Running Competitor.
Riley Bay began her undergraduate studies in Victoria, and graduated with a degree in psychology. She then completed her Masters of Physical Therapy at the University of British Columbia. Riley has gained further training in manual therapy techniques including Mulligan's Mobilization with Movement and The McKenzie Method. Through a combination of individualized therapeutic exercise, hands on manual therapy, and education, Riley is passionate about working together with her patients to help facilitate their return to the sports and activities that are important to them.