Running Injuries - Patellofemoral Pain Syndrome

Patellofemoral Pain Syndrome - An MSK Therapy perspective

Patellofemoral Pain Syndrome - An MSK Therapy perspective

Patellofemoral Syndrome tends to affect people who perform activities which involve a lot of repetitive knee bending activities. Motions such as squatting, running, jumping and even stair climbing can typically aggravate symptoms and also cause them in the first place. Hence, it is no surprise that Patellofemoral Syndrome is more common to certain types of sporting activities such as running (runners knee), rowing (rowers knee) and basketball (jumpers knee, though frequently this is more a case of Patella Tendinopathy). Patellofemoral Syndrome pain tends to manifest as anterior knee pain and more specifically behind the lower portion of the patella or kneecap. Symptoms typically feel worse after prolonged sitting with the knee fully flexed (as at the cinema), during activities that involve bending the knee (running, stair climbing, rowing, jumping). One may also notice crepitus (creaking or clicking type sounds) within the knee joint complex when moving from sitting to standing and vice versa. Patellofemoral pain is thought to occur due to an irritation of soft tissue structures around the patella, due to changed mechanics and or muscle imbalances within the kinetic chain (see Biotensegrity article for a better explanation). Such changes then affect how the patella moves and many knee-bending activities involve repetitive patella movements, either under standard load or additional weight-bearing load.

The Knee Joint Complex and knee pain

The knee joint complex is notably one of the most complicated joints structures within the body, with the shoulder joint complex arguably being the most complexed. Knee joints consist of multiple components including, bone, ligaments, tendons, bursae, articular cartilage, menisci, synovial fluid and fascia. Furthermore, there are many muscles with attachments via tendons, which pass over the knee joint complex and are an integral part of overall structure and function. Each of these structures of the knee provides different and in some cases multiple functions. Some typical examples of differing roles include shock absorption (menisci, cartilage), friction reduction (bursae, cartilage), structural stability (ligaments, tendons, muscles, fascia), physical movement (muscles) etc. Furthermore, many of the functions of specific structures are affected by other structures. For example, muscle function can alter due to changes in fascia and the fascial network.

Kinetic Chain and Knee Joint

 

The knee joint is a load-bearing structure and within the “Kinetic Chain”. The “Kinetic Chain” includes; Ankle joints, knee joints, hip joints, lumbar spine, thoracic spine and cervical spine. In essence, if the structure changes in one area of the kinetic chain, due to injury etc. then this alters the function of said structure at that given level. Each part of the kinetic chain can impact other areas further up or lower down the chain, and this can have a cumulative effect. The knee joint itself has a relatively limited range of motion, flexion (bending the knee), extension (straightening the leg/knee) and limited internal and external rotation (similar to when one turns the foot inwards or outwards).

The Knee Joint Complex (Femur and Patella)

In order, to understand Patellofemoral Pain Syndrome in more detail, it is useful to see the anatomy of the Patella and how the Patella interacts (tracks) with the Femur. The inferior aspect or lower portion of the Patella (apex) is attached to the superior or upper portion of the lower leg (Tibia), via the Patella Tendon. The upper part of the Patella (base) is attached to multiple muscles (quads) via tendons. The following diagram shows the posterior (back) of the Patella and that there is a “V” type shaped ridge in the middle. The posterior portion of the patella also has a covering of hyaline cartilage. Hyaline cartilage is a hard material, which covers areas of bone which have contact with other areas of bone. Joints with healthy hyaline cartilage slide very easily across each other with very little friction.

Image of the posterior portion of the Patella

Image of the posterior portion of the Patella (Kneecap)

Images produced with kind permission of 3d4medical.com from Essential Anatomy 5

(Copyright © 2018 - 2021 3D4Medical. All rights reserved.)

The inferior portion or lower part of the Femur has a small “V” shaped notch  (intercondylar notch, patellofemoral groove), as can be seen from the diagram below. The end of Femur also has a covering of hyaline cartilage, which comes into contact with the back of the patella and lower leg (tibia). The “V” shaped protrusion on the posterior side of the Patella fits neatly and slides over the “V” shaped notch on the Femur during knee flexion (bending) and extension (leg straightening) motions (patella tracking).

Image of the Femur and the notch for the patella to slide

Image of the Femur and the notch for the patella to slide

Images produced with kind permission of 3d4medical.com from Essential Anatomy 5

(Copyright © 2018 - 2021 3D4Medical. All rights reserved.)

<

Patella glide and Patella Braces

Changes in the mechanics of the normal patella sliding motion can result in irritation to soft tissue structures in and around the Patella. Irritation to the structures around the knee joint complex results in the initiation of the body's healing processes (see article on healing). The author is well aware how these changes in mechanics can affect the knee joint, as a runner, musculoskeletal and soft-tissue therapist. In some cases, the articular cartilage surface on the posterior portion of the Patella can become damaged too. Furthermore, changes affecting the Patella and knee joint function can affect other areas in the “Kinetic Chain”. Equally, other areas within the “Kinetic Chain” can be the cause of the Patellofemoral Pain Syndrome symptoms. Muscle tension within the quadriceps does affect the level of pressure applied to the Patella during knee movements, though these forces may be the symptom and not the cause. The pain associated with patellofemoral syndrome results in the body adapting strategies to avoid discomfort (see the Adaption article for more details) and these can further affect Biotensegrity. However, rather than seeing a professional, there can be a tendency to look for other solutions to knee pain, and the use of patella braces are all too common. In effect, such braces reduce the load on the patella by restricting movement at the knee joint, which does not address the actual cause. Reducing loads in one area will impact biotensegrity elsewhere, and the body will adapt accordingly. Hence, the knee may feel fine while running with a patella brace, but what other structures are now dealing with those subtle changes longer-term, and how long will it take to notice the effects? The following two diagrams show the knee joint connective tissue and the knee joint with all structures visible.

Image knee joint complex and connective tissues

Image (left) knee joint complex and connective tissues

Images produced with kind permission of 3d4medical.com from Essential Anatomy 5

(Copyright © 2018 - 2021 3D4Medical. All rights reserved.)

Furthermore, there are a large number of possible knee injuries with similar, and yet often subtle differences. Self-diagnosis with “Dr Internet” has a tendency not to end well, and so please be warned. It is better to seek advice sooner rather than later from a suitably qualified professional. Just masking symptoms with painkillers and letting symptoms get worse tends to lead to longer recovery times and chronic pain. See the Finding a good, ethical Musculoskeletal health professional - An MSK Therapy perspective article which covers attributes of consumer/patient-centred practitioners.

Knee Pain Treatment Options

As with many conditions with an inflammatory component, it is often wise to take action sooner rather than later and follow simple (R.I.C.E.) guidelines to start, Rest, Ice, Compression, Elevation. However, R.I.C.E. alone is not likely to identify the actual cause of the problem, and equally topical or oral anti-inflammatories will not address the cause either. Self-massage foam rollers and self-trigger point therapy (TPT) can both prove useful, though one needs to identify the source of the pain. Seeking advice and treatment from a suitably qualified professional tends to be the best way to identify and treat the cause of the problem. Based on personal treatment experience, a combination of advanced musculoskeletal and soft tissue therapy techniques has proved very useful. Some musculoskeletal methods are very good at addressing “structural” aspects affecting the kinetic chain and patella tracking. Other soft-tissue techniques work well in treating the affected dysfunctional muscles and thus “function” of the joint structures within the “kinetic chain”. That said, there have been occasions where Dry Needling and even IASTM type techniques were needed to address acute and or chronic soft tissue changes.

The next Running Related Article will cover Iliotibial Band Syndrome (ITBS) / Runner’s Knee.

The article was written by Terry Davis MChiro, BSc (Hons), Adv. Dip. Rem. Massag., Cert. WHS.

If you liked this article or found it of interest, there are lots more articles available via the TotalMSK main blog page, which has a brief description of all the articles to date. Alternatively, it is possible to stay up-to-date by subscribing to the RSS feed or following TotalMSK on social media.

Health, Wellness and Sports Injury Blog


About the Author

As of December 31st 2020, the author chose to leave the Chiropractic profession and pursue studies within the Physiotherapy field. He no longer works as a Chiropractor and works as a Myotherapist in Morningside, Brisbane. The author possesses an unusual background for somebody who trained as a Chiropractor (McTimoney). His education, training, and practical experience span over two decades and relate to both health's physical and mental aspects. He has also needed to push his own body and mind to the limits of physical and psychological endurance as part of his time serving in Britain's elite military forces. His education includes a bachelor of science degree in Business Management, with a specialisation in psychology and mental health in the workplace, an Integrated Masters in Chiropractic, MChiro and a multitude of soft-tissue therapy qualifications (see the about section for more details). His soft tissue qualifications range from certificate level right through to a BTEC Level 5 Advanced Diploma in Clinical Sports and Remedial Massage Therapy. Terry also has extensive experience in security, work, health and safety and holds relevant certifications. He has also taught as a senior course coach at Advanced Diploma level (Myotherapy / Musculoskeletal Therapy) in Australia, both theoretical and practical aspects including advanced Myofascial Release Techniques and has certification in training and assessment. Terry will have taught many of the first students to train as Myotherapists in Brisbane. Terry's combination of knowledge through education, training, elite military service, and personal injury history has paid dividends for the consumers he sees and has treated over the last 15 years. He has extensive experience treating chronic pain and work and sports-related musculoskeletal injuries. Terry is still very active and enjoys distance running, kayaking, mountain biking and endurance-type activities.