Patellofemoral Pain Syndrome: Symptoms, Causes and Treatment

Table of Contents

Patellofemoral Pain Syndrome is a challenging knee injury because even in 2021 the exact causes remain unclear and no single treatment works equally well for everyone.

Newer research examined different treatment approaches for different subgroups among those with patellofemoral pain syndrome and while the results are promising, we’re still far from a complete understanding of the injury.

This page will show you how to best get rid of patellofemoral pain syndrome, based on what we know today.

Symptoms

The symptoms of patellofemoral pain syndrome are1:

Diffuse pain behind or around the kneecap
Squatting, climbing stairs, running, sitting, jumping, or kneeling usually worsen the symptoms

Usually the pain in PFPS increases gradually2 and it often becomes chronic3. Participants of the research studies on patellofemoral pain syndrome had symptom durations as high as 3+ years4.

The symptoms of patellofemoral pain syndrome — In PFPS the pain is usually diffuse around or behind the kneecap.

Patellofemoral pain syndrome can also lead to psychological symptoms such as kinesiophobia5 (fear of pain due to movement), elevated anxiety, depression, and pain catastrophizing6 (assuming the worst will happen).

Diagnosis

Unfortunately, there is no gold standard diagnostic test to confirm the diagnosis of patellofemoral pain syndrome7. Your doctor will diagnose the injury through a physical examination and by inquiring about your pain history8.

Your doctor will then have to rule out knee injuries with similar symptoms through differential diagnosis9. Injuries that could mimic the pain of PFPS are10:

Hoffa’s syndrome
Osgood Schlatter Syndrome
Sindig-Larsen Syndrome
IT Band Syndrome
Patellar Tendonitis
Plica syndrome
Intra-articular injuries such as osteoarthritis or rheumatoid arthritis
Traumatic injuries like patellar fractures, injured ligaments, and meniscal tears

Imaging tests such as MRI or ultrasound can be useful for a diagnosis via exclusion, but they can’t help diagnose patellofemoral pain syndrome directly11.

Causes and Risk Factors

Patellofemoral Pain Syndrome can occur in athletes and non-athletes12. Its exact causes remain unclear13, even to this day, which is why it is also described as a “black hole” in orthopedic medicine14. Yet, we do have a list of potential causes15:

Patellar maltracking16
Muscle weakness (e.g., quads17, hip abductors and external rotators18, trunk side flexors19)
Delayed vastus medialis muscle activation, strength, or morphology20
Lack of flexibility of leg muscles (e.g., calves, hamstrings, and quads21)
Overpronation22
Prolonged and excessive forces pulling on the patella in lateral direction23
Abnormal femoral24, tibial25, or foot rotation26
Excessive hip adduction27 during movement
Misalignment of the hip during movement28 (e.g., contralateral pelvic drop)
Reduced strength and or motor control of the trunk and core muscles29
Anatomical factors30 (e.g., patella alta, hypoplasia of medial patellar facet, shallow trochlear groove31, femoral anteversion and inclination32)
Overloaded medial stabilization structures (retinaculum) in the knee due to excessive lateral forces33
Faulty running technique34
Female gender35
Reduced blood flow in or around the kneecap36
Reduced proprioception37
Reduced extension ability of the big toe38

To a large extent it remains unclear which of these factors are causative and which are the result of activity reduction due to pain39.

Additionally, causes of patellofemoral pain syndrome are likely different between genders40 and even in one gender, different subgroups of PFPS likely exist41.

Treatment

Treating patellofemoral pain syndrome successfully is challenging, because 10 people with PFPS may well have 10 different causes that contribute to their pain42. However, based on the research I’ve read, I would suggest the following treatment steps, ideally in that order.

Step 1) Work on the Mental Side

One study found that participants with patellofemoral pain syndrome looked for social support less than the healthy control group43. The same research also revealed that those with PFPS were less able to relax when faced with a problem.

Other research revealed that misconceptions about the pain caused by the injury correlate with lower function and, ironically, higher pain44.

Cultivating a cautiously optimistic attitude is an important first step of PFPS treatment.

You can soften the negative psychological effect the injury can have by reminding yourself that:

While PFPS is complex and frustrating, imaging scans of the knee will often come back clean. This means that in many cases, the structures inside the knee are healthy.

In other words, chances are you will get significantly better just by doing a couple of exercises.
Physical and psychological stress can both contribute to the pain45. This means your recovery will go better if you relax. Don’t obsess over your training, over “lost” progress, or even about the pain.

Putting yourself under pressure because you got hurt will slow your recovery. It is what is for now and with the right approach it will get better. Give your body the time it needs.
Chances are you will notice a significant improvement within a month of doing the right exercises for your individual situation46. Don’t expect progress to happen in just a few weeks or even days. It takes a while.
Resting the knee is important to aid your recovery, but ignoring the injury and leaving it unaddressed will lead to more pain and frustration in the future.

Now is the best time to work on it.

Yes, we’re still a fair bit away from a complete understanding of patellofemoral pain syndrome, but the treatments we’ve developed so far do work in most cases.

Step 2) Improve Strength & Flexibility

The treatment exercises for patellofemoral pain syndrome should always be done without pain or in the pain-free range of motion.

The following list summarizes what you need to work on and provides some example exercises.

A) Improve the strength of:

Hip abductors (exercise: side-lying hip abductions)
Hip external rotators (exercise: side-lying clamshells)
Hip extension (exercise: two- and single-legged glute bridges)
Calves (exercise: calf raises)
Quadriceps Muscles (exercises: wall sit, leg press, leg extension – depending on what’s tolerated)
Hamstrings (exercises: deadlifts, single-leg deadlifts)
Trunk Side Flexors (exercises: side bridge)
Hip Hike Exercise

You can adapt the exercises based on how your knee reacts:

If there is pain during knee extension, open kinetic chain exercises with more knee flexion (40 – 90° knee angle) may work better.

If deeper knee flexion is painful, working with closed kinetic chain exercises in lower knee flexion (0 – 40° knee angle) may produce better results47.

Very slow squats with an elastic band are an advanced strengthening exercise for PFPS. Only work in the pain-free range of motion and take 20+ seconds for one repetition.

As you can see, it is not enough to just work on the muscles of the knee. In fact, combining knee with hip exercises delivered superior results in research48.

B) Massage, stretch, and mobilize:

Calves
Quads
Hamstrings
Hip Flexors

This simple foam-rolling sequence will help tight leg muscles relax.

The standard foam-rolling sequence works well in addition to whatever stretches you like to do for the respective muscles. Here’s a stretching video that provides some exercise ideas:

Step 3) Improve Motor Control

Muscle strengthening alone is not enough to change the way someone moves49, so we also need to work on motor control directly.

Interestingly, one study on dancers found that the injury was less common among those with LOWER range of motion at the foot, ankle, and hip50. This suggests that improving stability (i.e., ability to prevent unwanted movement) may be beneficial for some of those with PFPS.

Exercises I would suggest are:

A) Balance Drill

In the balance drill, keep your knee aligned over your toes. You can make the exercise harder by closing your eyes.

Stand with your feet hip-width apart and pointed forward.

Imagine your knees are flashlights and point their beams straight ahead.

Now balance on one foot while making sure the knee of that leg keeps pointing straight forward. Do not let it point towards the other side.

Keep your hips and shoulders parallel to the ground as you lift the foot.

Don’t lean to one side and don’t lift one side’s hip up.

The movement should happen almost completely in the legs. Do not move the upper body.

B) Core Activation Work

This topic cannot be covered in just a few paragraphs, but here’s a simple exercise to get you started:

Lie on your back with your knees flexed and feet on the ground.

Make sure your lower back touches the ground.

Keep the lower back in touch with the ground and then begin to walk your feet out until your legs are straight or until your lower back begins to lift.

Brace your core muscles so that your lower back stays on the ground throughout the exercise. You should feel it partly in your abs, but also in the muscles on the side of your abs.

Keep your lower back on the ground throughout the exercise.

Once you can control your hip movement you can begin doing leg raises with bent knees to make it more challenging.

C) Step-Ups & Step-Downs

Once you can control the position of your hip and torso in the balance drill you can try step-ups.

Stand in front of a 10-inch box or step with your feet hip-width apart and pointed forward.

Place one foot on the box so that it points straight ahead.

You can step onto the box or as pictured, stand on it and touch the heel of the other foot to the ground. Maintain perfect leg alignment throughout the exercise.

Step up slowly, without momentum, while pointing your knee straight ahead.

Keep your hips and shoulders parallel to the ground, just like in the balance drill.

Summary

These are very basic motor control drills to help you get started. The details required by a full program would be too much too cover here. However, the technique cornerstones are the same for all standing exercises:

Feet hip-width apart, parallel, and pointed straight forward (not turned out to the side)
Knees pointed straight ahead and aligned over the toes (not moved towards the mid-line of the body – keep the knees apart)
Hips and shoulders remain parallel to the ground (don’t lean sideways to compensate for weak hips)

Stick to those rules in all movements you do throughout your day.

Step 4) Use Adjunct Treatments If Necessary

Certain adjunct treatments have worked well for some people with patellofemoral pain syndrome. These include:

Icing for short-term pain management 51
Taping (benefit should be felt almost immediately, if not it likely won’t help you)
Orthotics (beneficial for people with over-pronation/flat feet)
Chiropractic adjustments (expert consensus is against back manipulation for PFPS52, but some low-quality studies showed benefits53)
Dry Needling & Acupuncture54

These additional treatments can be beneficial, but they do not replace the need for strengthening exercises and for improving motor control as mentioned earlier.

Step 5) Work on Gait & Running Technique

Research on gait retraining for patellofemoral pain syndrome has repeatedly produced good results55. You can practice this by walking on a treadmill in front of a mirror or by recording yourself.

The technique cues are the same as for the motor control exercises we talked about earlier (feet forward, knees forward and part, hip and shoulders parallel to the ground).

Running with a forefoot strike can help reduce anterior knee pain.

Studies on running technique showed that running with a higher cadence, shorter stride length, and – most importantly – with a forefoot strike led to reduced symptoms in those with patellofemoral pain syndrome.

So once you return to running, focus on landing on the balls of your feet and taking shorter steps. Be aware that calf soreness can occur as a side-effect56, so increase mileage gradually.

Your Rehab Plan

This page is just a very good starting point for rehab of patellofemoral pain syndrome. It is not meant to be exhaustive.

You can use my suggestions as scaffolding, around which you can then construct your own rehab plan, depending on your body’s needs and your doctor’s advice.

I hope you can get well soon.

– Martin

Footnotes

1 Khayambashi et al. 2012, p. 22; Cook et al. 2010, p. 18; Davis, Powers 2010, pp. A1; van der Heijden, Rianne A et al. 2015, p. 13; Song et al. 2009, p. 410; Jensen et al. 1999, p. 522; Levinger, Gilleard 2005, p. 84; Bolgla et al. 2008, p. 12; Robinson, Nee 2007, p. 232; Barton et al. 2008, p. 529; Davis, Powers 2010, pp. A14; van Linschoten et al. 2006, p. 207; van Cant et al. 2017, p. 299; Neal et al. 2019, p. 270; Nunes et al. 2020, p. 707; Ophey et al. 2021, p. 301; Stefanyshyn et al. 2006, p. 1846; Nakagawa et al. 2008, p. 1052

2 Jensen et al. 1999, p. 522

3 Witvrouw et al. 2000, p. 480; IRELAND et al. 2003, p. 671; Rathleff et al. 2013, p. 5

4 Callaghan, Oldham 2004, p. 959; Robinson, Nee 2007, p. 236; Sutlive et al. 2004, p. 54; Fukuda et al. 2012, p. 826; Baldon, Rodrigo de Marche et al. 2015, p. 1485; Collins et al. 2009, p. 163

5 Priore et al. 2020, p. 613

6 Selhorst et al. 2021, p. 1268

7 Cook et al. 2010, p. 18; van der Heijden, Rianne A et al. 2015, p. 13; Fernandez Cuadros, Marcos Edgar et al. 2017, p. 204

8 Cook et al. 2010, p. 22

9 Rees et al. 2019, p. 227

10 van der Heijden, Rianne A et al. 2015, p. 9; van Cant et al. 2017, p. 299

11 Haim et al. 2006, p. 227

12 Earl, Hoch 2011, p. 154

13 Leibbrandt, Louw 2018, p. 218; van Linschoten et al. 2009, p. 1; van der Heijden, Rianne A et al. 2016, p. 111; Fernandez Cuadros, Marcos Edgar et al. 2017, p. 203; Rees et al. 2019, p. 227; Matthews et al. 2020, p. 1416; van der Heijden, Rianne A et al. 2015, p. 13

14 Yañez-Álvarez et al. 2020, p. 839

15 Saltychev et al. 2018, p. 393

16 Draper et al. 2009, p. 572; Lankhorst et al. 2013, p. 197; DUFFEY et al. 2000, p. 1830

17 Neal et al. 2019, p. 273

18 Willson, Davis 2009, p. 81; Dierks et al. 2008, p. 452; IRELAND et al. 2003, p. 673; Ferber et al. 2011, p. 145; Magalhães et al. 2010; Lankhorst et al. 2013, p. 200

19 Cowan et al. 2009, p. 586

20 Cowan et al. 2009, p. 586; Jan et al. 2009; Cowan et al. 2001, p. 187

21 Witvrouw et al. 2000, p. 484; Ophey et al. 2021, p. 301; Piva et al. 2005

22 Boling et al. 2009, p. 2110; McPoil et al. 2011, p. 293; Davis, Powers 2010, pp. A29

23 Callaghan, Baltzopoulos 1994, p. 84

24 Dierks et al. 2006; Lee et al. 1994; Tennant et al. 2001, p. 157; Souza, Powers 2009, p. 584; Davis, Powers 2010, pp. A27

25 Lee et al. 2003, p. 686; Salsich, Perman 2007, p. 521

26 Willson, Davis 2008a, p. 207

27 Willson, Davis 2008b, p. 606; Davis, Powers 2010, pp. A29; Noehren et al. 2013, p. 1122; Neal et al. 2016, p. 73; Rees et al. 2019, p. 227; Stefanyshyn et al. 2006, p. 1850

28 Cowan et al. 2009, p. 584; Willson, Davis 2009, p. 81; Souza, Powers 2009, p. 585; Neal et al. 2016, p. 73; Dierks et al. 2008, pp. 454–455

29 Baldon, Rodrigo de Marche et al. 2015, p. 1485; Zarei et al. 2020, p. 265; Earl-Boehm et al. 2018, p. 546; Dierks et al. 2011, p. 698; Foroughi et al. 2019, p. 221

30 Willson, Davis 2009, p. 76

31 Rezvanifar et al. 2019, p. 1235; Keser et al. 2008

32 Souza, Powers 2009, p. 580

33 Stefanyshyn et al. 2006, p. 1844

34 Dierks et al. 2011, p. 698

35 Boling et al. 2010, p. 728

36 Näslund et al. 2007, p. 1668; Selfe et al. 2003, p. 140; Sanchis-Alfonso et al. 2005

37 Baker et al. 2002, p. 213

38 Sutlive et al. 2004, p. 56

39 Prins, van der Wurff, Peter 2009, p. 14; Saad et al. 2018, p. 413; Rathleff et al. 2013, p. 5; Stefanyshyn et al. 2006, p. 1844

40 Csintalan et al. 2002; Lee et al. 2003, p. 688; Draper et al. 2009, p. 574; Neal et al. 2016, p. 75; Prins, van der Wurff, Peter 2009, p. 13

41 Selfe et al. 2016, p. 873; Selfe et al. 2018, p. 37

42 Sutlive et al. 2004, p. 50

43 Witvrouw et al. 2000, p. 485

44 Selhorst et al. 2020, p. 24; Selhorst et al. 2021, p. 1268

45 Selhorst et al. 2020, p. 24

46 Ferber et al. 2015, p. 373

47 Bolgla, Malone 2005, p. 80

48 Crossley et al. 2016, p. 848

49 Rabelo, Nayra Deise dos Anjos et al. 2017, p. 280

50 Steinberg et al. 2012, p. 563

51 Fernandez Cuadros, Marcos Edgar et al. 2017, p. 204

52 Crossley et al. 2016, p. 850

53 Vegstein et al. 2019, p. 923

54 Bizzini et al. 2003, p. 14; Jensen et al. 1999, pp. 523–525; Ma et al. 2020, p. 1682

55 Noehren et al. 2011, p. 694; Willy et al. 2012, p. 1049; Neal et al. 2016, p. 78; Davis et al. 2020, p. 105; Bonacci et al. 2018, p. 459

56 Bonacci et al. 2018, p. 460

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Patellofemoral Pain Syndrome – Symptoms, Causes, and Treatment Exercises [2021 Update]